data/train/batch_000036.jsonl

{"text": "this class can be used to encrypt data ( messages, files ) and hide that data in images using steganography techniques. steganography is the art and science of writing hidden messages in such a way that no one apart from the intended recipient knows of the existence of the message ; this is in contrast to cryptography, where the existence of the message itself is not disguised, but the content is obscured. it reads a given image in gif, jpeg or png formats, encrypts data supplied by the user ( a message, a file, a collection of both ) and hides the encrypted data in the image by making subtle colour changes to certain pixels to store the data in the image symbolically. the resulting image is generated in png format ( because png is lossless ). it can also perform the reverse operation by extracting the original data previously stored in an image using this package. the advantage of steganography over cryptography alone is that messages do not attract attention to themselves, to messengers, or to recipients. an unhidden encrypted message, no matter how unbreakable it is, will arouse suspicion and may in itself be incriminating, as in some countries encryption is illegal.", "subdomain_id": "subdomain_quantum_cryptography", "similarity_score": 0.6187609849078383, "token_count": 258, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:6cb51bbe-4c54-449d-bf2e-e30f053d1522>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:44.677624"}
{"text": "the intellectual value of physics as a science can hardly be overstated. physics is concerned with the most fundamental questions one can ask about the physical world : what is it, ultimately, made of? what rules govern its behavior? how do simple laws of nature lead to diverse phenomena? physicists address more practical matters as well : the understanding of magnetic materials and semiconductors and optics which was pioneered by physicists in the 20th century made possible the development of computers and communications networks thanks to which you can read this webpage today. physicists are not limited to studying only certain kinds of questions that fall within the traditional domain of physics : they work with biologists and biochemists to explore cells and viruses ; they work with atmospheric scientists in sensing the properties of the upper atmosphere ; they work with chemists in finding new materials for diverse applications. of course they also continue to study atoms and subnuclear particles and other more traditional physics topics, but what characterizes a \u201c physicist \u2019 s approach \u201d to any problem are precise and innovative experimental techniques and detailed theoretical analyses. the value of a physics degree in the marketplace is also an important matter : if you \u2019 re going to work as hard as an engineering student, shouldn \u2019 t you be rewarded commensurately? it must be admitted that students of physics do not have a clearly laid out career path in the same way as engineering majors, but that is because an undergraduate degree in physics can serve as a launching point for diverse career trajectories. the american institute of physics has been collecting data concerning the experiences of physics graduates, and they have issued a series of reports ( such as the 2010 initial employment report and physics bachelor \u2019 s one year later ) which you might find interesting. what do csu physics majors do after graduating? - some go on to advanced study in physics. our majors are prepared for the most rigorous graduate programs ; recent students have entered physics ph. d. programs at cambridge, yale, university of maryland and university of california, among others. - some go on to advanced study in other fields, such as engineering, atmospheric science, and medical physics. our colleagues in the engineering college are generally very happy to take on students with undergraduate physics degrees as graduate students ; if you want to work on the leading edge in almost any area of technology a bachelor \u2019 s in physics offers a sound foundation on which to build. - students who have gone directly into the workforce have been hired by companies such as agilent, lockheed martin, and raytheon. a strength of the colorado", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6036708434935393, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:ba43d7d2-e15f-4312-850b-17a2f0b1d0e9>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:44.683960"}
{"text": "one important topic concerns the psychology of personality. how do we define personality? this question is similar to the question concerning what is the self. the definition of self can be viewed as similar to the definition of personality. personality definition : personality refers to an individual ' s enduring pattern of behaviors, thoughts, and emotions. personality psychology is a subfield of psychology, and personality psychology involves personality theories and personality research findings. there are a number of theories that may explain individual differences in behavior. theories of personality can be placed into at least five categories : psychoanalytic personality theories, humanistic personality theories, trait personality theories, learning personality theories, and cognitive personality theories. these personality theories can be considered important psychological theories. a focus of each type of personality theory is indicated below : psychoanalytic personality theories : the unconscious mind. humanistic personality theories : personal responsibility and personal growth. trait personality theories : personality characteristics that exist on a continuum. learning personality theories : learning as a result of environmental influences. cognitive personality theories : differences in how people process information. an example of a psychoanalytic personality theory is freud ' s defense mechanisms. maslow ' s hierarchy of needs theory can be viewed as a humanistic personality theory. observational learning can be viewed as a learning personality theory. an example of a trait personality theory is the big five personality traits. in order to have a clearer understanding of these personality theories, i will explain how each type of theory may explain a person who is often late to work. a trait theory may explain the late behavior with respect to being low on the dimension of conscientiousness. a humanistic personality theory may explain the late behavior with respect to failing to take responsibility for one ' s negative behavior. a psychoanalytic theory may explain the late behavior in terms of an unconscious defense mechanism. a learning theory may explain the late behavior with respect to observing other employees being late for work. finally, a cognitive theory may explain the late behavior with respect to beliefs about the importance of the job. there are many possible attributes that could be considered personality traits. what is a personality trait? personality trait definition : a personality trait is a characteristic that describes a person ' s personality. some examples of personality traits include the following adjectives that may describe some people : intellectual, shy, outgoing, funny, kind, curious, sensitive, and selfish. one view of personality traits is that there are five basic dimensions that describe individual differences in personality. the article below includes a description of the five dimensions. the big five personality traits personality", "subdomain_id": "subdomain_quantum_field_theory", "similarity_score": 0.6078158478289251, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:5a5aa3b7-a05d-445a-bf90-032bdc4ed173>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:44.747757"}
{"text": "describing a buy interest in which a dealer is asked to offer stock, often involving a capital commitment. antithesis of in touch with. ways to obtain clear photographs of soviet satellites. the turbulence of the atmosphere blurs images to such an extent that even digital enhancement can ' t improve them. later, as part of the strategic defense initiative strategic defense initiative ( sdi ), u. s. government program responsible for research and development of a space - based system to defend the nation from attack by strategic ballistic missiles ( see guided missile )., popularly known as the star wars program, the military studied adaptive optics as a way to compensate for atmospheric distortions when focusing a ground - based laser weapon on an incoming missile. eventually, the technology found its way into astronomy, where it can overcome the atmospherically induced twinkling and blurring that afflict images of stars ( sn : 6 / 8 / 91, p. 358 ). a few years ago, williams and his coworker junzhong liang paid a visit to robert q. fugate at the starfire optical range starfire optical range is a united states air force research laboratory located at 34. 964 n, 106. 463 w on the kirtland air force base in albuquerque, new mexico. their primary duty, according to their official website, is to \" develop and demonstrate optical wavefront control at kirtland air force base kirtland air force base is located in the southeast quadrant of albuquerque, new mexico, adjacent to the albuquerque international sunport. the base is the third largest installation in air force materiel command, covering 51, 558 acres ( 209 km\u00b2 ) and employing over 23, 000 people, near albuquerque to learn about adaptive optics for their own vision research. fugate pioneered the astronomical use of the technique. the basic strategy in adaptive optics is to collect light waves with a deformable mirror whose shape can be adjusted to compensate for distortions in an image. in photographing a retina, williams uses a flexible mirror with 37 pistons on the back that can change the shape of the reflecting surface. because the wavelength of light is less than i micrometer micrometer ( mikrom ` \u0259t\u0259r, mi ` krome ' t\u0259r ). 1 instrument used for measuring extremely small distances., the pistons don ' t need to move more than about 3 micrometers. the researchers coupled the mirror to a special high - resolution camera and took images of the retina both when the mirror was flat and when", "subdomain_id": "subdomain_quantum_optics", "similarity_score": 0.6146048579795049, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:5a039f5b-0a68-4873-9060-8efb9b0b0554>", "chunk_index": 3, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:45.115768"}
{"text": "called optical tweezers to get the likes of polystyrene micro - beads and even living cells to \" stick \" to a laser beam, or to trap atoms at ultra - low temperatures. scientists have devised a method to reduce the time used to simulate how proteins take on their signature three - dimensional shape. such important information to comprehend their function is usually obtained using often very costly experimental techniques. new research reveals why some children are badly affected by negative family conflicts while other children survive without significant problems. researchers found that the way in which children understood the conflicts between their parents had different effects on their emotional and behavioral problems. where children blamed themselves for the conflicts between their parents, they were more likely to have behavioral problems, such as anti - social behavior. but if their parents ' fighting or arguing led to a child feeling threatened, or fearful that the family would split up, the child was more likely to experience emotional problems, such as depression. researchers have discovered that the greater wax moth is capable of sensing sound frequencies of up to 300 khz - - the highest recorded frequency sensitivity of any animal in the natural world. engineers have created a system of sensors that detects fruit odors more effectively than the human sense of smell. for now, the device can distinguish between the odors compounds emitted by pears and apples. scientists have created an electronic nose with 32 sensors that can identify the odors given off by chopped pears and apples. faced with a choice between higher insurance prices or exercising, people who were obese enrolled in and stuck with internet - tracked walking program for a year. the herschel space observatory has made detailed observations of surprisingly hot gas that may be orbiting or falling towards the supermassive black hole lurking at the center of our milky way galaxy. researchers have quantified the significant value that concentrating solar power plants can add to an electric grid. enzymes could break down cell walls faster - - leading to less expensive biofuels for transportation - - if two enzyme systems are brought together in an industrial setting, new research suggests. america ' s urban forests store an estimated 708 million tons of carbon, an environmental service with an estimated value of $ 50 billion, according to a recent study. the first successful cornea transplant with donor endothelial tissue preloaded by an eye bank has been performed. women with unintended pregnancy are four times more likely to suffer from postpartum depression at twelve months postpartum, suggests a new study. exposing skin to sunlight may help to reduce blood pressure, cut the risk of heart", "subdomain_id": "subdomain_quantum_optics", "similarity_score": 0.6101720288312157, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:1fbaa5b3-245e-4cad-8d7f-610812ad635e>", "chunk_index": 4, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:45.413231"}
{"text": "a soft matter paper by roberto piazza and co - workers has been highlighted on a number of italian news - sites, ansa, sole 24 ore and galileo. the paper combines experimental and theoretical studies on what buoyancy actually is, and its relation to the archimedes \u2019 principle. what buoyancy really is. a generalized archimedes \u2019 principle for sedimentation and ultracentrifugation roberto piazza, stefano buzzaccaro, eleonora secchi and alberto parola soft matter, 2012, 8, doi : 10. 1039 / c2sm26120k an excerpt of the piece by the italian on - line magazine, galileo this is the way i rewrote archimedes \u2019 principle sandro iannaccone | published june 28, 2012 13 : 55 it is the archimedes \u2019 principle : a body immersed in a fluid receives an upward thrust equal to the weight of the volume of fluid displaced. a definition that all children learn from from school, established since twenty - three centuries. yet, this time they are the researchers at politecnico of milan to proclaim the famous \u201c eureka! \u201d : their studies have shown that in some cases the principle, in its classical formulation, is not in agreement with the experimental results. the scientists then set out a more general version of this law of physics, presented in this interview with roberto piazza, director of the laboratory soft matter of politecnico, author of \u201c soft matter, the stuff that dreams are made of \u201d ( springer, 2011 ) and, together with alberto parola of the university of insubria, of this work published in \u201c soft matter \u201d.", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.66358036552757, "token_count": 337, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:d3f2ae60-633d-44ed-8a9f-e57a58ab3852>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:45.832728"}
{"text": "respective lives - aim towards producing multi - agent models for psycho - social dynamics, and some maths - learn from our research individually so knowledge is equated to real skill and experience ; we get better at what we do - provide some kind of community for people who are interested in exploring these kinds of ideas - honour the children or adults we teach with improved learning environments some lingo and metaphors given the convention regarding use of language, the following are used only as much as they point at real - life dynamics which we experience. extended metaphors provide some much needed accuracy. alternative descriptors are encouraged. eventually we might be able to use mathematics to describe certain dynamics. - psycho - social - - the phase - space of virtual engagement - subjectivity - - the location of the individual, fathomlessly deep, psychological makeup well beyond verbal description into the real of principle - belief ; also called singularity ; imagine a blackhole - event horizon of self - - most of us engage each other in terms of roles, where we do not open ourselves up but keep much of ourselves private ; the event horizon is where to delve into a person and go beyond mere role and social difference, but to really fall into the self - definition of a person - gravity of thought - - thoughts have certain mass, as it were, and we tend to fall into thinking patterns because of them - words as vectors - - words have effect, or at least, their use in certain contexts trigger semantic, emotional and behavioural responses whether we like them to or not ; hence words seem to have a life of their own - phase space - - the multidimensional space where will and words and behaviour and thought exist ; physicists use 3d and time for specific phase space of physical matter, whereas we have more subjective qualities - verifiable - - the science of objects is testable through falsity ; if we are to be rigourous with our research, we must have testability, and we test a thing by verifying it - self - emergent - - by thinking a thing, it exists, as least in the virtual space of thinking and if we speak about it, then it becomes real in a cultural sense, and here you are reading these words now ; we make things happen - subjectively immersed - - we are entirely part of the social dynamic ; pretending to be objective is a harmful delusion, and we must be as accurate as possible regarding our own involvement in the system we are describing as we talk about our experiences,", "subdomain_id": "subdomain_quantum_field_theory", "similarity_score": 0.6519527029755913, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:e0e11488-85e1-4f99-b6ab-543a87c4514b>", "chunk_index": 1, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.210854"}
{"text": "bohr v einstein by rochelle forrester \u00a9 all rights reserved published in 2002 the debate between bohr and einstein over the interpretation of quantum theory began in 1927 at the fifth solvay conference of physicists and ended at einsteinis death in 1955. the most active phase of the debate ran from 1927 to 1936 when bohr replied to the epr paper written by einstein and two colleagues. the debate took the form of various thought experiments invented by einstein in which it would be theoretically possible to measure complementary properties such as the position and momentum of a particle or its energy at a certain point in time. if these measurements were possible it would show that bohris idea of complementarity and heisenburgis uncertainty principle were wrong and that the quantum theory proposed by bohr, called the copenhagen interpretation, was wrong. before addressing einsteinis attack on bohris theory, it is necessary to examine the theory to see what einstein was objecting to. the best way to understand quantum theory is in comparison with the classical theory of physics derived from newtonian laws of motion, maxwellis electro - magnetic theory and statistical thermodynamics. classical physics provides a description of the physical world that assumes a continuity of motion and fields of force. this means that we are able to use a series of observations to see the changes in a particular system. we are able to given a continuity of description of the system as it under goes particular changes. classical physics also assumes causal interactions in space and time between bodies which are considered to be independent objects. the mathematics used to describe a physical system amounted to a theoretical model in which the terms of the theory correspond to the elements in the physical system. it was possible for example to make a series of measurements of the positions and motions of the planets and using newtonis laws to determine with certainty the past and future behaviour of the planets. as long as the system was closed and not subject to any external disturbances we could know the state of the system at any time, past or future. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 observations made of the system could confirm whether the predictions made under the theory were correct or not, but would not disturb the system itself. the system could be considered as being entirely independent of the observer and any disturbances caused by the observation or measurement could be controlled or allowed for by the observer. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 bohris theory for the quantum world differed radically from the classical theory in a number of respects. a key factor in bohris", "subdomain_id": "subdomain_quantum_mechanics", "similarity_score": 0.6890640440865233, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f2c085bc-3a48-4106-a649-2872169d8230>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.402459"}
{"text": "or measurement could be controlled or allowed for by the observer. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 bohris theory for the quantum world differed radically from the classical theory in a number of respects. a key factor in bohris theory was the discovery of planckis constant. in 1900 max planck while working on a problem in physics concerning blackbody radiation suggested that radiated energy should be seen as not being continuous as is assumed by classical theory, but as being composed of discrete indivisible bundles of energy. this unit of energy, also know as a quantum or the quantum of action, was soon used to explain other problems in physics such as the photo - electric effect where electrons are ejected from metals and the orbits of electrons in atoms. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 a further important factor in bohris theory was wave - particle duality. electro - magnetic energy had been assumed to consist of waves, but the discovery of planckis constant, the photo - electric effect and eventually in the 1920is the compton effect, where x - rays were found to knock electrons out of a gas, it was concluded that electro - magnetic energy could also behave as particles. quantum entities such as electrons were normally regarded as particles but were also found to behave as waves in certain experiments. this meant that both energy and matter were capable of behaving as both waves and particles. this was considered to be a problem as waves and particles had contradictory qualities such as waves are inherently in motion, spread out in space and may merge together to reinforce or cancel each other out, while particles may be stationary and occupy a single point in space and rebound of each other like billiard balls when they collide. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 bohris theory also concerned the problem of how can we objectively describe the things we can not directly experience. bohr considered we have no choice but to use the language of classical physics and our everyday macro - world experience when describing the quantum world. this is because there is no other language we could use. if we tried to use a purely theoretical language not related to our experiences in the macro - world, we would not be able to objectively communicate to each other what we thought was happening in the quantum world. such a language not being related to our common experiences in the macro - world would be ambiguous and would be unable to be used objectively to describe the quantum world. it is a necessary condition for the unambiguous communication of our ideas of", "subdomain_id": "subdomain_quantum_optics", "similarity_score": 0.7079455837131785, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f2c085bc-3a48-4106-a649-2872169d8230>", "chunk_index": 1, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.403523"}
{"text": ". such a language not being related to our common experiences in the macro - world would be ambiguous and would be unable to be used objectively to describe the quantum world. it is a necessary condition for the unambiguous communication of our ideas of the quantum world that they be in a language that relates to the everyday world we are all familiar with. the principle that we must use the familiar classical concepts to describe the quantum world is known as the correspondence principle. bohr actually used the term correspondence principle to refer to two separate ideas. the other use of the correspondence principle is the situation where the macro - world and the quantum world merge and where for the higher quantum numbers the classical and quantum theories produce the same calculations. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 a further factor in bohris thought was that if one wished to provide an objective description of the world, it is necessary to have external points of reference available. such external points of reference available in the macro - world are the concepts of space and time and of causality, yet these points of reference are not available in the quantum world. the only external points of reference available when investigating the quantum world are re - identifiable macroscopic particulars and measuring apparatus. it is the existence of such apparatus that allows quantum theory to be objective. ( horner, 1987, 149. ) the example is given of two identical pens which in the macro - world one can distinguish by virtue of their different spacial locations. if they were both put in a box which is then closed and shaken about, it will then no longer be possible to re - identify which pen is which. observations of the quantum world are like opening the box ; in both situations we have lost the continuity which exists in the macro - world. this leaves the macro - scopic measuring apparatus as the only frame of reference available for creating objective descriptions of the quantum world. ( horner, 1987, 204 - 205 ). this situation is forced on us by the quantum of action ( or planckis constant ) which causes the discontinuity which exists in the quantum world. a later measurement will render information gained by an earlier measurement to be of dubious value due to the interaction between the quantum entity being observed and the measuring apparatus. with no continuity in space and time available as a frame of reference and given the effect that observations have on the quantum entities being observed, the interaction between the quantum entity and measuring apparatus is the only frame of reference available. ( horner, 1987, 67 ). due to", "subdomain_id": "subdomain_quantum_mechanics", "similarity_score": 0.7060992442493359, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f2c085bc-3a48-4106-a649-2872169d8230>", "chunk_index": 2, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.404708"}
{"text": "and time available as a frame of reference and given the effect that observations have on the quantum entities being observed, the interaction between the quantum entity and measuring apparatus is the only frame of reference available. ( horner, 1987, 67 ). due to this bohr considered the quantum theory could not describe the unobserved state of quantum entities, but only the interaction between the entity and the measuring apparatus. the quantum world is observer dependant. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 a further important element in bohris thought is the concept of complementarity. complementarity provides a general framework to put together various aspects of nature which cannot be understood within a more restricted framework. it allows phenomena which might otherwise be considered contradictory, like wave - particle duality, to be put together. the contradiction is avoided as matter and energy do not behave as wave and particle at the same time in the same experiment. complementarity allows the complete description of quantum phenomena ; without it descriptions would be incomplete. bohr considered complementarity replaced but also embraced the classical concept of causality, when dealing with the quantum world. it is not possible to consider observations as being in a series, as one does in classical physics, in the quantum world. in the quantum world you have to go back and forth between sets of observations which may be put together under the framework of complementarity. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 the uncertainty principle established by heisenberg was also part of the copenhagen interpretation championed by bohr. the uncertainty principle states that it is not possible to obtain completely accurate measurements of certain pairs of properties of quantum systems, such as position and momentum or time and energy, at the same time. the more accurately one property such as position was measured, the less accurately momentum could be simultaneously measured. this is caused by the quantum of action which is of sufficient size to disturb quantum systems when we observe them and because the quantum of action is indivisible we cannot reduce the disturbance by reducing the amount of energy used to observe the quantum system. the other problem is that the disturbance is uncontrollable and unpredictable and so cannot be allowed for when observing quantum systems. the uncertainty principle meant that determinism, the ability to assess both the past and future behaviour of a physical system was no longer possible. the initial information required, for example both the position and momentum of a body is impossible to establish with certainty and any changes are unpredictable. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020", "subdomain_id": "subdomain_quantum_mechanics", "similarity_score": 0.6916105635108514, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f2c085bc-3a48-4106-a649-2872169d8230>", "chunk_index": 3, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.405811"}
{"text": "past and future behaviour of a physical system was no longer possible. the initial information required, for example both the position and momentum of a body is impossible to establish with certainty and any changes are unpredictable. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 the final element making up the copenhagen interpretation is the wave function invented by schrodinger, but which was interpreted by max born as being probability waves. it is not possible according to quantum theory to predict the behaviour of individual quantum systems ; rather we can only predict the probable behaviour of the individual system. this is caused by the discontinuity in the quantum world and because each measurement involves an interaction with the system being measured. this interaction, which disturbs the system, is uncontrollable and unpredictable. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 when a measurement is made the probability waves are considered to have collapsed to a specific state giving the actual position ( or whatever else is being measured ) of the quantum system. prior to the measurement the quantum system is considered not to have any real position at all. it is the actual act of measurement which brings the quantum system into existence or whatever property of the system that is being measured. this is because the focus of the copenhagen interpretation is on what can be known. it is not possible in principle to know what a quantum system is doing prior to measurement. the determinism that enables the behavior of bodies in the macro - world to be calculated simply does not exist in the quantum world. the indivisibility of the quantum of action and the fact that measurements disturb quantum systems in an uncontrollable and unpredictable way eliminates the possibility of determinism in the quantum world. bohris argument has been summarized by max jammer in dthe philosophy of quantum mechanicse as d1. indivisibility of the quantum of action. ( quantum postulatee ). 2. discontinuity ( or indivisibility ) of elementary processes. 3. uncontrollability of interaction between object and instrument. 4. impossibility of a ( strict ) spatio - temporal and at the same time causal description. 5. renunciation of the classical mode of description. e \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020", "subdomain_id": "subdomain_quantum_mechanics", "similarity_score": 0.689886582506174, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f2c085bc-3a48-4106-a649-2872169d8230>", "chunk_index": 4, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.406739"}
{"text": "\u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 ( as quoted in horner, 1987, 106 ) \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 a more detailed summary of bohris though is provided by horner. it is \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 d ( 0 ) all knowledge presents itself within a conceptual framework adapted to account for previous experience, and any such frame may prove to narrow to comprehend new experiences. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 ( i ) the quantum of action is a discovery which is universal and elementary. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 ( ii ) the quantum of action denotes a feature of indivisibility in atomic processes. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 ( iii ) ordinary or classical descriptions are only valid for macroscopic processes, where reference can be unambiguous. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 ( iv ) any attempt to define an atomic process more sharply than the quantum allows must entail the impossible, dividing the indivisible. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 ( v ) because of the limit of indivisibility a new and more general account of description and definition must be devised. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 ( vi ) it is a necessary condition for the possibility of unambiguous communication, that suitably refined everyday concepts be used no matter how far the processes concerned transcend the range of ordinary experience. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 ( vii ) our position as observers in a domain of experience where unambiguous application of concepts depends essentially on conditions of observation demands the use of complementary descriptions if description is to exhaustive. e unlike jammeris description this introduces both the correspondence principle as ( vi ) and complementarity as ( vii ). however both descriptions of bohris thought emphasize that it is the indivisibility of the quantum of action that is the cause of the need for a new non - classical theory for the quantum world. however bohris view of the situation was not accepted by einstein. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 einstein did not like bohris interpretation", "subdomain_id": "subdomain_quantum_mechanics", "similarity_score": 0.7340383531255157, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f2c085bc-3a48-4106-a649-2872169d8230>", "chunk_index": 5, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.409427"}
{"text": "the cause of the need for a new non - classical theory for the quantum world. however bohris view of the situation was not accepted by einstein. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 einstein did not like bohris interpretation of quantum theory. he did not like the uncertainty principle and the probability inherent in bohris theory. he considered dgod did not play dice. e he also did not like the discontinuity and the loss of causality involved in the theory. most of all he did not like the loss of a world that existed independently of our observations. einstein wanted a more complete view of the universe than bohris theory provided and he wanted a single view to cover both the quantum world and the macro - world. the view he considered ought to apply to both worlds was the view of classical physics with its independent reality, causality, determinism, continuity and space - time framework. einsteinis view was essentially ontological. he wanted to know what was going on dout theree. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 bohris view on the other hand was more epistemological. he was interested in what we can know and the conditions for the unambiguous communication of our observations of the quantum world. bohr accepts the existence of an indivisible quantum of action and the discontinuity of quantum processes that follow from the indivisible quantum of action. einstein on the other hand regarded the quantum of action as merely provisional or as a heuristic device rather than as the fundamental fact of nature bohr considered it to be. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 einsteinis criticism of bohris view of quantum theory began at the fifth solvay conference in brussels in 1927. einstein would invent thought experiments to show that the uncertainty principle or complementarity did not always apply. one such experiment involved the double slit experiment which einstein modified so it would be possible to tell which slit a particle passed through while still allowing the interference pattern to exist. if this was possible it would show a quantum entity acting as a particle ( i. e. when you can tell which slit it passed through ) and a wave ( due to the evidence of the interference pattern ) at the same time. this would contradict bohris idea of complementarity. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 einsteinis idea is shown on the diagram below : particles \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020", "subdomain_id": "subdomain_quantum_mechanics", "similarity_score": 0.6586879408968127, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f2c085bc-3a48-4106-a649-2872169d8230>", "chunk_index": 6, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.410766"}
{"text": "pattern ) at the same time. this would contradict bohris idea of complementarity. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 einsteinis idea is shown on the diagram below : particles \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 first screen \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 second screen \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 on rollers einsteinis modification of the double slit experiment is that the screen containing the two slits should rest on rollers and be able to move. a particle arriving at point p on the detecting screen would receive an upward kick as it went through the slit. this would mean the screen would receive a downward kick and the size of the kick would be greater if the particle had passed through slit 1 than if it had passed through slit 2. by measuring the motion of the screen it would be possible to tell which slit the quantum entity had passed through which involves the entity acting as a particle while at the same time retaining the interference pattern. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 bohr soon came up with a problem for einsteinis experiment. bohr considered that in order to see which slit the quantum entity had passed through it was necessary to measure the movement of the screen to a particular accuracy. any lesser degree of accuracy in the measurement will not provide us with the information required to tell us through which slit the entity went through. however due to the uncertainty principle there will be a degree of uncertainty as to the position of the slits. the uncertainty as to the position of the slits is sufficient to eliminate the interference pattern. this is because interference requires a certain relationship between the wavelength of the entity and the distance the two slits are apart and the distance between the two screens being distance between the two screens x wavelength distance between the two slits uncertainty in the position of the two slits in the experiment will eliminate the interference pattern. placing the first screen on rollers in order to observe the movement of the slits so it is possible to tell which slit the entity went through causes uncertainty in the position of the slits of a sufficient amount to eliminate the interference pattern. ( greenstein &", "subdomain_id": "subdomain_quantum_optics", "similarity_score": 0.6667038601907054, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f2c085bc-3a48-4106-a649-2872169d8230>", "chunk_index": 7, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.411898"}
{"text": "placing the first screen on rollers in order to observe the movement of the slits so it is possible to tell which slit the entity went through causes uncertainty in the position of the slits of a sufficient amount to eliminate the interference pattern. ( greenstein & zajonc, 1997, 86 - 88 ). \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 a further thought experiment invented by einstein at the fifth solvay conference involved a stream of electrons hitting a screen with a single slit in it. the electrons that pass through the slit would form a diffraction pattern on the second screen. a diagram is below : electrons \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 first screen \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 second screen einstein considered the experiment showed bohris theory could not describe the behaviour of individual electrons. if an electron arrived at a on the diagram above then we immediately know it has not arrived at b. however quantum theory does not explain why the electron arrived at a rather than b. it only predicted the probability that a particular electron would hit a particular point on the second screen. einstein suggested we should be looking for a better theory. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 bohris reply was that there was a change in momentum of the electron as it passed through the slit due to interaction between the electron and the screen. the width of the slit which effects the position of the electron and the wave cone brings a degree of uncertainty into the position of the electron as its momentum changes. this uncertainty was consistent with heisenbergis uncertainty principle and the only way to predict with certainty where an individual electron would land would be to have a slit of zero width ( e. g. no slit at all ) or an infinite number of diffraction rings which is no diffraction at all. ( horner, 1987, 119 - 121 ). \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 einstein also attempted to disprove quantum theory at the sixth solvay conference in 1930 with the dclock in the box experimente. this involved a box with a hole in one wall covered by a shutter which could be opened and closed by a clock mechanism inside the box. the box also contained radiation which would add to the weight of the box. the box would be weighed and then at a given moment the clock would open the shutter allowing a single photon of radiation to escape. the box could then", "subdomain_id": "subdomain_quantum_optics", "similarity_score": 0.6596673438190801, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f2c085bc-3a48-4106-a649-2872169d8230>", "chunk_index": 8, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.413049"}
{"text": "mechanism inside the box. the box also contained radiation which would add to the weight of the box. the box would be weighed and then at a given moment the clock would open the shutter allowing a single photon of radiation to escape. the box could then be re - weighed, the difference between the two weights telling us the amount of energy that escaped using the formula e = mc2. under the uncertainty principle it is not possible to obtain an exact measurement of the energy of the released photon and the time at which it was released. einsteinis experiment was designed to show such exact measurements were possible, the clock measuring the time of release of the energy and the weighing of the box disclosing the amount of energy involved. a diagram showing einsteinis idea is below. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 bohris reply involved looking at the practicalities involved in making the required measurements. the box had to be weighed so it had to be suspended by a spring in a gravitational field. to weigh the box it is necessary to compare a pointer attached to the box against a scale. after the photon had left the box weights can be added to the box to restore the pointer to the same position against the scale as it had been before the photon escaped. the weight added to the box gives the weight of the escaped photon. however this involves a measurement of the box to ensure the pointer is back at its original position. this measurement is subject to the uncertainty principle concerning the position and momentum of the box which brings uncertainty into the measurement of the weight of the box. if there is uncertainty in the weight of the box, then there will be an uncertainty in the energy of the released photon. there will also be uncertainty in the time of the released energy as the speed of time depends upon the position of a clock in a gravitational field. this position is uncertain then the time of the release of the photon will also be uncertain. this means both the time and the amount of energy released will be uncertain so einsteinis thought experiment did not contradict the uncertainty principle. ( greenstein & zajonc, 1997, 89 - 92 ). \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 einsteinis thought experiments had previously tried to show quantum theory was wrong, but in 1935 he presented a paper arguing quantum theory was incomplete. in this paper einstein and two colleagues proposed a thought experiment which involved two co - related particles emitted from a source and moving away from the source in opposite directions at the speed of light. measuring the position of particle1 can", "subdomain_id": "subdomain_quantum_metrology", "similarity_score": 0.7055160541715368, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f2c085bc-3a48-4106-a649-2872169d8230>", "chunk_index": 9, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.414145"}
{"text": "arguing quantum theory was incomplete. in this paper einstein and two colleagues proposed a thought experiment which involved two co - related particles emitted from a source and moving away from the source in opposite directions at the speed of light. measuring the position of particle1 can give an exact idea of its position, while measuring the exact momentum of particle 2 allows us to know the exact momentum of particle1 due to the co - relation of the two particles. einstein also argued that the measurement of particle1 could not disturb particle 2 due to the impossibility of faster than light signaling. this means we can know the exact position and momentum of particle 1 contrary to the uncertainty principle. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 bohris reply was that if you make a measurement of particle 1 then this involves the complete measuring system so that it is not possible to claim a relevant and precise \u2020 measurement of the conjugate property of particle 2. bohr considered both particles existed within the same frame of reference so that a measurement of particle 1 will disturb particle 2 as it disturbs the whole frame of reference. if they are not considered to be in the same frame of reference, then the measurements would be considered to be successive experiments which does not establish simultaneous measurements of motion and position. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 subsequent developments on the epr experiment involved a theorem invented by john bell and experiments carried out by alain aspect and others have tended to support bohris position. they are usually interpreted as requiring the abandonment of either the idea of locality or the idea that quantum systems have their properties independently of the act of measurement. \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 \u2020 einsteinis attacks upon the copenhagen interpretation are widely regarded as having failed to show the theory is either wrong or incomplete. his criticisms of the theory and especially the eventual results of the practical application of the epr idea have greatly strengthened the theory, so that it became the orthodox interpretation of the quantum world. the debate between einstein and bohr was conducted with the two talking past each other, einstein arguing how the quantum world ought to be, while bohr argued how the quantum world can be known to us. bohr accepted that there were some fundamental limits on our knowledge of the quantum world, ( such as the quantum of action ) which as a matter of principle we are unable to overcome. einstein never accepted those limits, but was never able to show to get around them. that does not mean that einsteinis view that the quantum world is like the macro -", "subdomain_id": "subdomain_quantum_mechanics", "similarity_score": 0.7016388650817401, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f2c085bc-3a48-4106-a649-2872169d8230>", "chunk_index": 10, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:46.415183"}
{"text": "the theory of species was originally conceived by andre joyal and is used to analyze combinatorial structures in terms of their generating functions. in my talk on friday i showed how the theory of species can be developed from a functional programming perspective with a view towards using them to analyze datatypes. i am diverging a bit from the classical definitions in defining a generalisation of species which matches with a specialisation of the notion of a container. a generalized species is given by a family, the idea is that is the set of structures which have positions. e. g. consider the species of leaf - labelled binary trees : is the set of the two binary trees, which have leafs ( insert picture here ). given a species we assign a functor by. the definition corresponds to the generating function, but this is a function on the reals not on sets ( see my recent posting on sets and numbers ). note that is just where we identify a natural number with the set of numbers smaller than it ( usually called fin in dependently typed programming ). category question : if species are the objects, what are the morphisms? let \u2019 s define a category. given species, a morphism is given by a triple [ math ] ( f, g, h ) [ / math ] : calculating the numbers of positions. calculating the new shape. assigning source positions to target positions. i leave it as an exercise to define identity and composition of those morphisms. the definition of morphisms hopefully becomes clear when we give their interpretation as natural transformations, i. e. to every species morphism we assign a natural transformation : operations on species : given species : - coproducts are easy : - products are a bit more involved : - composition is also interesting : given a species we can construct its initial algebra. to be continued", "subdomain_id": "subdomain_quantum_field_theory", "similarity_score": 0.6017647989895532, "token_count": 375, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:c8284d9b-9bfe-4215-b723-4488049a78bf>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:47.123612"}
{"text": "this standard contains mathematical expressions and procedures that must be implemented for correctly assessing uncertainty affecting measurements on power systems. the document relies on the instrumentation typically used, with particular focus on digital instrumentation, and addresses typical kinds of uncertainty sources. the theory reported in the standard iso / iec guide 98 - 3 : 2008 uncertainty of measurement - - part 3 : guide to the expression of uncertainty in measurement ( gum : 1995 ) and supplements is used as background for expressing the relationships to be used for the evaluation of the uncertainty in measurements on power systems. the guidelines developed in this document can be used to evaluate uncertainty budget when performing the measurement of a given quantity on electric power systems as well as to correctly write their value in official documents like specifications and test reports. this document contains a variety of examples to deeply discuss and explain the provided guidelines. the concepts presented can be extended to more general measurement uncertainty evaluation problems. get involved in the development of this standard contact the ieee - sa liaison simply click here to voice your interest. kathryn bennett learn more about standards participationanyone can participate, there are a variety of programs and services to facilitate the involvement of industry and the public. more become a member and ballot on this standardmembership empowers you to participate & lead in the development of standards. tell me more", "subdomain_id": "subdomain_quantum_metrology", "similarity_score": 0.6056346092536434, "token_count": 259, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:8f93671d-d190-4523-9064-cd1b69025174>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:47.143324"}
{"text": "topology refers to the way in which the network of computers is connected. each topology is suited to specific tasks and has its own advantages and disadvantages. the choice of topology is dependent upon there are four major competing topologies most networking software support all topologies. the bus cable carries the transmitted message along the cable. as the message arrives at each workstation, the workstation computer checks the destination address contained in the message to see if it matches it ' s own. if the address does not match, the workstation does nothing more. if the workstation address matches that contained in the message, the workstation processes the message. the message is transmitted along the cable and is visible to all computers connected to that cable. there are three common wiring implementations for bus networks physical implementation of a bus the above diagram shows a number of computers connected to a bus cable, in this case, implemented as thin ethernet. each computer has a network card installed, which directly attaches to the network bus cable via a t - connector. it is becoming common to use 10baset ( utp ) for implementing ethernet lans. each workstation is wired in star fashion back to a concentrator wiring centre ( hub ). the hub is a multi - port device supporting up to about 32 ports. one of these ports is connected to a server, or the output of the hub can be connected to other hubs. ethernet 802. 3 : carrier sense multiple access with collision detection ( csma / cd ) this protocol is commonly used in bus ( ethernet ) implementations. multiple access refers to the fact that in bus systems, each station has access to the common cable. carrier sense refers to the fact that each station listens to see if no other station is transmitting before sending data. collision detection refers to the principle of listening to see if other stations are transmitting whilst we are transmitting. in bus systems, all stations have access to the same cable medium. it is therefore possible that a station may already be transmitting when another station wants to transmit. rule 1 is that a station must listen to determine if another station is transmitting before initiating a transmission. if the network is busy, then the station must back off and wait a random interval before trying again. rule 2 is that a station which is transmitting must monitor the network to see if another station has begun transmission. this is a collision, and if this occurs, both stations must back off and retry after a random time interval. as it takes a finite time for signals to travel down the cable, it is possible", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6141935865364359, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:9571af55-1931-4039-8d65-049cbbc7175a>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:47.438114"}
{"text": "gravity reference systems - german gravity reference systems - european gravity reference systems - global gravity reference systems the free fall of a test mass is recorded with high accuracy. in order to minimize non - gravitational disturbing influences, such as air drag, buoyancy etc. the test mass moves in an evacuated chamber. the \" absolute \" determination of the gravitational acceleration results from the use of physical standards of highest accuracy : a rubidium standard for time measurement and an iodine - stabilized laser for length measurement. by means of the absolute gravimeter fg5 ( manufacturer : micro - g lacoste inc., usa ), which represents the currently best possible technical development status, measuring accuracies of \u00b120 \u2026 30 nm / s2 ( \u00b12 \u2026 3 \u00b5gal ) can be obtained under favorable ambient conditions. this corresponds to a relative accuracy of \u00b12 \u2026 3 x 10 - 9. bkg applies the absolute gravimeter a10 with a measuring accuracy of \u00b1100 nm / s2 made by the same manufacturer for field measurements. absolute gravimeter measurements complete the geodetic reference systems - by the setup of an absolute gravimetric standard in an earthbound reference system - and allow the independent detection of vertical point displacements or mass variations, caused by e. g. tectonically induced movements of the earth \u2019 s crust, post - glacial uplifts or changes of the sea level. in this context special emphasis is given to the combination with levelling measurements and geodetic space techniques like vlbi - very long baseline interferometry, slr \u2013 satellite laser ranging, and gnss \u2013 global navigation satellite system. gravimeters record temporal changes of the earth \u2019 s gravity field. whereas in conventional relative gravimeters the gravity acceleration is measured by means of a test mass suspended on a spring, in the case of the superconducting gravimeter ( sg ) the very stable magnetic field of a superconducting coil serves as reference force. the test mass is a superconducting hollow sphere the position of which is kept constant in a control system. the electrical current in this control system is continuously measured and digitized with high - resolution. superconducting gravimeters are characterized by a very high resolution of the measuring signal ( < 0. 1nm / s2 ) and a small instrumental zero drift. by using superconducting coils, in which - after an initialization - currents flow continuously and constantly, a long - term stability of", "subdomain_id": "subdomain_quantum_metrology", "similarity_score": 0.6409293959200808, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:671a132a-b04f-423c-ae96-cad8e507f23f>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:47.986425"}
{"text": "the measuring signal ( < 0. 1nm / s2 ) and a small instrumental zero drift. by using superconducting coils, in which - after an initialization - currents flow continuously and constantly, a long - term stability of 0 and 50 nm / s2 per year can be reached. this way, the possibility of recording a broad spectral range of the acceleration changes with high resolution opens up. the spectrum reaches from the seismic eigen - modes of the earth with periods lenghts from 10 minutes via the earth tides with predominantly half - day and full - day periods up to the variation of the centrifugal acceleration as a result of the polar motion with periods of 365 and 435 days ( chandler period ) and to long - period tides with a period interval of 18. 6 years. by the observation of temporal gravity field variations the following objectives are pursued : - high - precision acquisition of the tides of the earth body for deriving elastic parameters - investigation of attraction and deformation effects as a result of oceanic, atmospheric and hydrological mass displacements - acquisition of gravity variations due to polar motion - detection of seismically induced oscillations of the earth - control of gravity standards by combining and comparing with absolute gravity measurements. the \" frankfurt gravimeter calibration platform \" developed at bkg uses artificially generated accelerations for the calibration of relative gravimeters and was specially designed for the test of superconducting gravimeters. the calibration system consists of three spindle blocks operated by stepping motors, by means of which the gravimeter to be tested can be synchronously lifted and lowered in a sinusoidal movement. in dependence on the amplitude of motion and its periodicity, artificial accelerations are superimposed to the earth \u2019 s normal gravitational force. since the amount of acceleration and the period interval are known, the calibration factor and the frequency transfer function of the superconducting gravimeter can be derived.", "subdomain_id": "subdomain_quantum_metrology", "similarity_score": 0.6112395211248578, "token_count": 406, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:671a132a-b04f-423c-ae96-cad8e507f23f>", "chunk_index": 1, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:47.987367"}
{"text": "' s interior, or to do away with the standard model itself. for a while it seemed possible that the sun was a lot cooler on the inside than anyone had thought, a discovery that would have had consequences for the ultimate fate of the solar system. fortunately, when physicists began looking for ways the standard model could be modified to allow for the mysteriously low rate of solar neutrino emissions, they realized that if neutrinos did have mass, they were capable of flipping freely in space between three different \" flavours \" - - only one of which earlier neutrino observatories had been capable of observing. on june 18, 2001, the sno - - basically a giant tank of heavy water surrounded by cameras that could detect the \" flash \" created by a single neutrino penetrating to the earth ' s core - - solved all of these problems with the release of just one batch of results. it turned out that neutrinos do have mass, that earth is receiving all three types of neutrinos from the sun and that the total number agrees with established models. nobel laureate john bahcall described the discovery in 2004 as \" epochal \", \" revolutionary \" and the \" fingerprints on the smoking gun \" of the solar - neutrino problem. in the future, the discoveries that the sno made possible may be placed on a par with ben franklin ' s own research into electricity. already \" neutrino astronomy \" is an important field ; detectors like sno will give astronomers early warning of the next supernova in our galactic neighbourhood. as the sno ' s \" smoking gun \" showed, neutrino detection is like having an extra sense to work with when it comes to understanding the solar core. and futurists are spinning wild ideas for neutrinobased imaging and telecommunications - - ideas that now seem as far - fetched, but just as tempting, as alternating current would have been to franklin.", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6024033317079269, "token_count": 397, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:622fd98a-2358-496d-a4f9-c05904f2f98c>", "chunk_index": 1, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:48.087230"}
{"text": "university of california, berkeley, chemists are reimagining catalysts in ways that could have a profound impact on the chemical industry as well as on the growing market for hydrogen fuel cell vehicles. catalysts are materials typically metals that speed up chemical reactions and are widely used in the synthesis of chemicals and drugs. they also are employed in automobile catalytic converters to change combustion chemicals into less - polluting emissions and in fuel cells to convert water into hydrogen. the problem with catalysts, however, is that chemical reactions occur only at edges of or defects in the material, while the bulk of the metal \u2013 often expensive platinum \u2013 is inactive and wasted. in an article appearing this week in the journal science, uc berkeley chemists show how to construct a catalyst composed only of edges and demonstrate that it can catalyze the production of hydrogen from water as readily as the edges and defects in regular catalysts. \" this is a conceptual advance in the way we think about generating hydrogen, a clean - burning fuel, from water, a sustainable source, \" said christopher chang, associate professor of chemistry and howard hughes medical institute investigator at uc berkeley. \" our new catalyst is just first generation, but the research gives us and the community a path forward to thinking about how to increase the density of functional active sites so that molecules and materials can be more effective catalysts. \" at the moment, creating these catalysts in the lab is not cheaper than using traditional catalysts, but efforts by chang and others to simplify the process and create materials with billions of active sites on a ridged wafer much like a ruffles potato chip could allow cheaper, commercially viable fuel cell catalysts. \" the development of new earth - abundant catalysts for water splitting is an essential component of the global effort to move away from fossil fuels and towards solar energy, \" said coauthor jeffrey long, uc berkeley professor of chemistry and faculty scientist at lawrence berkeley national laboratory. chang and his uc berkeley colleagues worked with a common catalyst, molybdenite, that is less expensive than platinum and of increasing interest as a fuel cell catalyst. composed of molybdenum and sulfur ( mos2 ), the material catalyzes reactions like the splitting of water into hydrogen and oxygen only at the edges, where triangles of molybdenum and two sulfur atoms stick out like pennants. \" these edge sites look like little moss triangles, and the triangular area does the business, \" chang said. using complex organic synthesis techniques, chang said he and his", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6383158667820291, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:fd726872-7a1f-41c9-bdfb-a40fccf2ac27>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:48.628513"}
{"text": "triangles of molybdenum and two sulfur atoms stick out like pennants. \" these edge sites look like little moss triangles, and the triangular area does the business, \" chang said. using complex organic synthesis techniques, chang said he and his colleagues created a small carbon framework to hold the moss triangle so that \" every molecule has a discrete edge site that is a catalytically active unit. \" when lots of these single - molecule catalysts were dumped into acidic water and even seawater, they generated hydrogen for several days without letup. in future research, chang hopes to assemble billions of these molecules on a thin, ridged wafer, maximizing the number of catalytic sites for a given volume and boosting ultimate efficiency. \" there are many other types of materials out there for which people might want to generate edge - site fragments rather than use a bulk material with just a few edge or defect sites, \" chang said. \" with hydrogen being touted as a clean burning fuel that generates no co2, creating cheaper and better catalysts has become a big and important field now. the main push is toward more earth - abundant materials than the rare metals like platinum. \" chang and long ' s uc berkeley coauthors are post - doctoral fellows hemamala i. karunadasa, elizabeth montalvo and yujie sun, and professor of chemistry marcin majda. chang, long and sun also hold positions at lbnl. kuranadasa is now a post - doc at the california institute of technology. the research was funded through the joint center for artificial photosynthesis, a department of energy energy innovation hub and lbnl ' s helios solar energy research center. aaas and eurekalert! are not responsible for the accuracy of news releases posted to eurekalert! by contributing institutions or for the use of any information through the eurekalert! system.", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6135255012991576, "token_count": 384, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:fd726872-7a1f-41c9-bdfb-a40fccf2ac27>", "chunk_index": 1, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:48.629347"}
{"text": "material. the strip portion 300 a defining the capillary portion 240 of the nozzle 200, in addition to being comprised of a harder or more wear - resistant material, or coated with a hard coating, may also comprise one or more inserts installed therein so as to form at least a part of the capillary portions 240, wherein such inserts may be comprised of, for example, sapphire, diamond, or other suitable material. as previously discussed, the initial strip portion 300 a can thus be reversed such that the opposing side of the major dimension becomes the fluid contact surface, thereby possibly doubling the service life of the device 100 before replacement is required. further, the subsequent strip portion 300 b can be incorporated into many manifold configurations, wherein such a manifold generally comprises an apparatus on which the jet strip device 100 is mounted, thereby obviating the need for the subsequent strip portion 300 b ( such that the jet strip device 100 comprises only the initial strip portion 300 a ) and providing relatively large flexibility with respect to configurations of the jet strip device 100. such nozzles 200 may thus provide longer continuous operation of hydroentangling machines and thereby realize significant cost savings, while also concurrently providing for greater ranges of operational parameters and improved performance. many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.607849247751843, "token_count": 371, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:dd17bac5-0158-415d-8dfd-2ac208116b3b>", "chunk_index": 16, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:48.920349"}
{"text": "it has taken almost 50 years to conceive and build and has cost $ 600 million, but now nasa ' s gravity probe b spacecraft could be upstaged by telescopes on the ground. the craft is designed to accurately test einstein ' s general theory of relativity. according to the theory, a gyroscope orbiting a massive object such as the earth should experience two forces that gradually cause it to \" precess \", pushing its axis of spin out of alignment. the stronger force, known as the geodetic effect, is caused by the earth warping the fabric of space - time. the other, known as the gravitomagnetic effect, is caused by the rotating earth dragging space and time around with it. gravity probe b, which carries ultra - sensitive gyroscopes, was conceived in the 1950s to measure these forces, but was only launched in april 2004. it has yet to take any measurements. francis everitt, the physicist in charge of the project at stanford university, us, says the probe should produce results by mid - 2006. meanwhile, astronomers have been studying binary pulsars - two rapidly spinning neutron stars orbiting each other - to measure these effects. the gravitational fields of pulsars are so strong that both of the forces predicted by einstein should show up relatively clearly in the precession of each pulsar in a binary system, much like that in a gyroscope. last week, ingrid stairs of the university of british columbia in vancouver, canada, and colleagues reported for the first time that the observed precession in a binary pulsar due to the geodetic effect was consistent with that predicted by general relativity. so the big prize for gravity probe b is now the gravitomagnetic effect, which is hundreds of times weaker than the geodetic effect and is unlikely to be seen in the near future by stairs ' s team. but earlier in 2004, astronomers announced the discovery of a binary system in which the pulsars are much closer together and orbit each other every 2. 4 hours. burst of activity the discovery has triggered a burst of activity to gather data on the pulsars from radio telescopes all over the world and a hunt through historical records for past observations of the system. the huge gravitational forces at work in it should make some of the effects predicted by relativity easy to see, says robert o ' connell, a theoretical physicist at louisiana state university in baton rouge, us. for instance, the geodetic effect should cause the axes", "subdomain_id": "subdomain_quantum_metrology", "similarity_score": 0.6221233329446785, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:4efe78b8-c71b-4b24-85d0-e8fd7f9d3a1f>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:50.719527"}
{"text": "josephson ' s research has turned up an astounding variety of dead ends. there was, for instance, food irradiation. starting as early as the 1950 ' s, the soviets had tried irradiating fruits, fish, meat and potatoes as a means of preservation. they also tried irradiating hens, seeds and barnyard breeding stock to increase productivity. ' ' the image of the mighty atom joining us at the dinner table was no more a reasonable hope than that of other images promoted during the glory days of atomic energy : the atom and nuclear engines, the atom as excavator and the atom and unlimited electric energy. ' ' none of it worked well ; much of it did not work at all. there was the attempt to use small nuclear bombs for peaceful purposes, to aid in oil and gas drilling, to put out fires in oil and gas wells, to create underground storage space for hazardous wastes and to dig canals, harbors and reservoirs ( ' ' correcting the mistakes of nature, ' ' the soviets said ). and there was russian imperialism within the soviet union, as moscow exported reactors for research and power to the other republics. much was wasted, but, as josephson explains, his story is also a tale of heroism. whatever american physicists accomplished, they did it without having to dodge the destruction brought about by the invasion of the nazis or the purges carried out by stalin and the k. g. b. the russians were world leaders in physics. not for nothing is our term for the machine that allows fusion a russian one, the tokamak. josephson might have done well to note, though, that ' ' too cheap to meter ' ' is a term invented here, to describe a fantasy that flourished in both countries, to the benefit of neither. the soviets hardly had a monopoly on insular decision - making, unrealistic expectations about cost and reliability and institutional momentum that put bad ideas on artificial life support. but ' ' red atom ' ' does not distinguish among causes. how much is red and how much is atom? one longs for josephson to isolate the factors, to separate the universal human constants here, like the messianic drive of physicists, from the particular dictates of the soviet system, with its penchant for standardization and megaprojects and the small role it allowed for public input or market analysis. how does this compare, say, with france, a nation that is highly centralized and has a strong political overlay", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6184050511590053, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:1795a771-ae39-478d-b923-b87ec9cf95a5>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:50.853568"}
{"text": "electroplating aluminum articles adhesion of metals to solid substrates methods for producing adhesive bonds between substrate and polymer employing an intermediate oxide layer moisture - curable polyurethane composition process for adhering polyurethane elastomer to metal color plus clear coating system utilizing organo - modified clay in combination with organic polymer microparticles color plus clear coating system utilizing organo - modified clay applicationno. 10140230 filed on 05 / 06 / 2002 us classes : 427 / 409metal base examinersprimary : lightfoot, elena t attorney, agent or firm foreign patent references international classesb05d 7 / 00 descriptionfield of the invention this invention relates to a process for preparing a chrome substrate for application of a polymer coating, and more particularly to a process for preparing a chrome substrate to achieve a durable bond between the chrome substrate and asubsequently applied polymer film. background of the invention traditional chrome plating creates a smooth, bright chrome finish. it has long been desired to have tinted lustrous metallic finishes, such as black chrome, gold - tinted chrome, and other tinted or colored metallic finishes for decorativepurposes. more specifically, there has been a desire for clear polymeric decorative coatings that allow the brightness and luster of chrome plating to be seen, while modifying the appearance by imparting a color or tint to the chrome plating. several methods have been used in an attempt to achieve colored metallic finishes. one method involves electroplating, wherein black chrome and bronze finishes can be created. a problem with the electroplating methods is that it is verydifficult to consistently obtain a desired colored metallic finish. another disadvantage with the electroplating techniques is that they are generally limited to black and bronze colors or combinations thereof. another method that has been used for obtaining colored metallic finishes involves physical vapor deposition ( pvd ). this method offers a wider variety of colors than the electroplating method. however, physical vapor deposition is veryexpensive, and therefore, its use for achieving a desired colored finish is extremely limited. another problem with physical vapor deposition is that it is difficult to control the gloss of the finishes. another method that has been attempted for obtaining colored metallic finishes involves applying transparent organic polymer coating containing a dye, pigment or other colorant on a chrome - plated substrate. this method is convenient, and offersa very wide variety of color finishes. however, the use of organic coatings on chrome - plated substrates has been", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6096298875749022, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:60e45506-8c9c-41a4-9b07-6dd35e03e594>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:50.958053"}
{"text": "describes a process for creating unique surface finishes on chrome - plate substrates. the process provides an economical way of creating surface finishes similar to black chrome, and other coloredmetallic finishes. the process employs an adhesion enhancer that can be applied as a primer or as an additive to a polyurethane composition. more particularly, in one embodiment, the process includes steps of applying an aqueous primer composition to achrome substrate, wherein the primer composition containing a silane adhesion promoter ; drying the applied primer composition ; applying a urethane composition over the chrome plate on which the aqueous primer was applied and dried ; and curing theurethane composition to form a polyurethane film. both the film and the adhesion between the film and chrome plating are durable enough for practical applications such as in the automotive interior industry and in electronic devices such as cellulartelephones. however, the processes described in this reference do not consistently provide the required adhesive durability needed for exterior automotive applications. therefore, a process for forming a polymer film on a metal surface to provide acoating or tinted coating which exhibits consistently improved adhesive durability suitable for exterior automotive applications and other applications in which the coating is subjected to weather or other extreme conditions is desired. summary of the invention the invention pertains to a process for preparing a chrome substrate for application of a polymer coating, wherein the substrate preparation consistently enhances adhesion and durability of the adhesion between the chrome substrate and thepolymer coating. the improved adhesive durability meets or exceeds criteria for interior and exterior automotive applications. in addition to automotive applications, the processes of this invention may be advantageously employed in other applicationsin which adhesive durability between a chrome substrate and a polymer coating is desired such as residential building door and cabinet hardware and plumbing. the process involves contacting the chrome substrate with an acid solution for a period of time sufficient to modify the surface of the chrome substrate whereby improved adhesion and improved adhesive durability are achieved between a polymercoating and the chrome substrate. in certain embodiments, the acid treatment is an anodic treatment. in accordance with certain aspects of this invention, the acid treated chrome surface is further treated with a silane compound to enhance adhesion with a subsequently applied polymer coating composition. in accordance with a preferred aspect of the invention, improved adhesion between a chrome substrate and a polymer coating composition is achieved by", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6092675129562451, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:60e45506-8c9c-41a4-9b07-6dd35e03e594>", "chunk_index": 2, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:50.961434"}
{"text": "the acid treated chrome surface is further treated with a silane compound to enhance adhesion with a subsequently applied polymer coating composition. in accordance with a preferred aspect of the invention, improved adhesion between a chrome substrate and a polymer coating composition is achieved by contacting the chrome substrate with an acid solution for a period of time sufficient to modifythe surface of the chrome substrate ; treating the chrome substrate with a silane compound to protect the surface from contaminants and / or oxidation during handling, storage, and / or shipment ; washing the treated substrate after handling, storage and / orshipment ; and treating the washed substrate with a silane compound to enhance adhesion with a subsequently applied polymer coating composition. these and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification and claims. description of the preferredembodiments the expression \" polymer \" and derivatives thereof are meant to encompass homopolymers, copolymers, terpolymers, and polymers comprised of four or more monomers. similarly, the expression \" copolymer \" and derivatives thereof is meant to encompasspolymers that are the reaction product of two or more monomers, including terpolymers and polymers that are the reaction product of four or more monomers. the words \" comprising \", \" including \", \" containing \" and derivatives of these words are not meant toexclude other polymers, ingredients and / or components. similarly, the articles \" a \" and \" an \" are generally meant to mean at least one, and should not be construed to mean only one. the process of this invention may be used for forming a polymer film coating on generally any metal surface. however, the invention is particularly useful for providing a tenacious, durable adhesive bond between a polymer film coating and achromium surface. chrome surfaces have been particularly difficult to coat with a polymeric film that adheres to the surface tenaciously and durably, and in particular it has been difficult to provide a polymeric film coating on chrome surfaces whichcan withstand extended use in exterior automotive applications, and other hostile or extreme environments. accordingly, preferred applications for the invention relate to the provision of functional or decorative polymer film coatings on bright chromesurfaces, especially electroplated chrome surfaces. in each of the embodiments of this invention, a chrome surface, such as an electrodeposited chrome plating or a chrome coating formed by", "subdomain_id": "subdomain_quantum_field_theory", "similarity_score": 0.6327402907471817, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:60e45506-8c9c-41a4-9b07-6dd35e03e594>", "chunk_index": 3, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:50.962874"}
{"text": "electromagnetic devices, from power drills to smart - phones, require an electric current to create the magnetic fields that allow them to function. but researchers at the university of california, los angeles have developed a method for switching tiny magnetic fields on and off with an electric field \u2014 a sharp departure from the traditional approach of running a current through a wire. the new composite can control magneto - electric activity at a scale of just 10 nm. many collisions occur between asteroids and other objects in our solar system, but... excess heat, like that generated by extended use of a computer or other device,... a team of scientists in the united states has combine three different imaging methods... bacteria on a surface wander around and often organize into highly resilient communities known as biofilms. it turns out that they organize in a rich - get - richer pattern similar to the distribution of wealth in the u. s. economy, according to a new study. a research team led by ucla bioengineers has developed a way to program and control the shape of fluids flowing through pipes or conduits without the need to solve complex and time - consuming fluid - motion equations. this strategy could allow researchers to tap the vast, unrealized potential of fluid - flow applications. leaving the house in the morning may seem simple, but with every move we make, our brains are working to create maps of the outside world that allow us to navigate and remember where we are. ultimately, the brain constructs its own pinpoint geographical chart that is far more precise than anything you ' d find on google maps. but just how neurons make these maps of space has fascinated scientists for decades. until now. doctors have begun to categorize breast cancers into four main groups according to the genetic makeup of the cancer cells. which category a cancer falls into generally determines the best method of treatment. but cancers in one of the four groups \u2014 called \" basal - like \" or \" triple - negative \" breast cancer ( tnbc ) \u2014 have been particularly tricky to treat. researchers have developed a potential treatment for tnbc that uses nanodiamonds. taking a significant step toward improving the power delivery of systems ranging from urban electrical grids to regenerative braking in hybrid vehicles, researchers at the university of california, los angeles have synthesized a material that shows high capability for both the rapid storage and release of energy. like finally seeing all the gears of a watch and how they work together, researchers from the university of california, los angeles and the university of california", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6254600622903013, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:a8a5b6ec-9d45-4cae-a495-5f5e241cfeac>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:51.166555"}
{"text": "turned this \" soft lithography \" process on its head. a team of researchers have used surface photochemical reactions to probe the critical role of substrate morphology on self - assembly and ligand environment, determining that molecules on curved surfaces have a greater range of orientations and, as a result, react more slowly than do molecules on flat surfaces. for years, many scientists had thought that plate tectonics existed nowhere in our solar system but on earth. now, a university of california, los angeles scientist has discovered that the geological phenomenon, which involves the movement of huge crustal plates beneath a planet ' s surface, also exists on mars. researchers have come across an unexpected potential use for fluoxetine \u2014 commonly known as prozac \u2014 which shows promise as an antiviral agent. using molecular screening, a california research team found that fluoxetine was a potent inhibitor of replication in viruses found in the gastrointestinal tract. the discovery could provide another tool in treating human enteroviruses that sicken and kill people in the u. s. and around the world. researchers in california have recently described a new kind of polymer solar cell that produces energy by absorbing mainly infrared light, not visible light, making the cells nearly 70 % transparent to the human eye. the device was made from a photoactive plastic that converts infrared light into an electrical current. from driftwood traveling down a river to a blood cell flowing through your artery, objects moving in a stream of fluid are mostly thought to passively go with the flow but not disturb it in controllable ways. researchers at the university of california, los angeles have recently found that objects within a confined stream create controllable disturbances that can be used to move mass or heat at high rates, potentially providing simple solutions to performing chemical reactions on particles or cooling microelectronic chips. the ability to distinguish and isolate rare cells from among a large population of assorted cells has become increasingly important for the early detection of disease and for monitoring disease treatments. a new optical microscope could make the tough task a whole lot easier. it uses photonic time - stretch camera technology and is the world ' s fastest continuous - running camera. a team of university of california, los angeles researchers has created the most powerful high - performance nanoscale microwave oscillators in the world, a development that could lead to cheaper, more energy - efficient mobile communication devices that deliver much better signal quality. a groundbreaking new study led by university of california, los angeles climate expert alex hall shows that", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.633405400653988, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:a8a5b6ec-9d45-4cae-a495-5f5e241cfeac>", "chunk_index": 3, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:51.171995"}
{"text": "the peak oil crisis : the quantum fusion hypothesis for nearly 25 years now, the idea that it might be possible to extract unlimited amounts of energy from the nucleus of a hydrogen atom at low temperatures has been pretty much in disrepute. when major laboratories were unable to detect nuclear reactions on their work benches back in 1989, the whole notion of what was then called \" cold fusion \" was debunked as junk science and for most remains so to this day. fortunately however, a few scientists kept plugging away on just how one could get heat from the nucleus of a hydrogen atom. now their efforts seem to be paying off. in recent months numerous respected scientists have been reporting at scientific gatherings that they are seeing increasing amounts of heat, which can only be coming from nuclear reactions, during experiments with hydrogen loaded into nickel and palladium under the proper conditions. there have been so many of these reports by reliable and respected scientists that it has become absurd to claim that the phenomenon is fraudulent or that all these scientists are mistaken in their observations. currently there are at least six different organizations around the world saying they have a commercially useful heat - producing device under development which they will be demonstrating soon. to the comfort of skeptics, most of these organizations have been very circumspect in releasing details of their devices and the physics behind them. there are, of course several reasons for this reticence. some may hope to keep their heat - producing secret as long as possible in hopes of making money from their discovery. more likely, however, is that while they have developed a way to produce heat, they really don ' t understand the physics underlying their device. this situation however seems to be changing following a lengthy interview with a fellow out in berkeley, california by the name of robert godes of brillouin energy. he has been working in this field for the last ten years and says that he not only has a reliable heat - producing device, but also understands the physics behind it \u2013 which he calls the quantum fusion hypothesis. he says that this theory of just how low - energy nuclear reactions work has allowed the development of a device which produces heat immediately and reliably. most interestingly, godes says he has shared his insights with scientists at the los alamos nuclear laboratories and sri international, one of the leading us laboratories investigating the phenomenon. he says that both have verified that his theory does indeed work and that they can now produce heat from hydrogen every time they try. godes ' hypothesis is interesting for those with even", "subdomain_id": "subdomain_quantum_thermodynamics", "similarity_score": 0.6558398221809723, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:2437148e-00ac-4d84-b3cd-f9b22b323293>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:51.181238"}
{"text": "and sri international, one of the leading us laboratories investigating the phenomenon. he says that both have verified that his theory does indeed work and that they can now produce heat from hydrogen every time they try. godes ' hypothesis is interesting for those with even a smattering of physics in their background. first of all, he holds that the heat which is coming from infusing hydrogen into nickel or palladium is not coming from \" cold fusion \" in the classic sense of the term. it is not a deuterium fusing with deuterium reaction as takes place in the sun or h - bombs and which requires extremely high energies. what seems to be happening in this new kind of fusion is that when hydrogen is \" loaded \" into nickel or palladium and subjected to the proper kind of an electromagnetic pulse, the hydrogen nucleus which is a positively charged proton acquires an electron which turns it into a low energy free neutron. now a low energy free neutron is something very nice to have for it quickly combines with other protons to form deuterium, tritium and finally quadrium. the quadrium only lasts for an instant before undergoing a process called beta decay turning it into helium. this is where einstein and e = mc2 comes in. the beta decay of quadrium results in a loss of mass which is turned into heat. if all this pans out as claimed, it could be one of the most important secrets of nature that has ever been discovered, for our energy problems are over. this new hypothesis, it is not yet a theory, says that it would be possible to use water as the source of all energy that mankind could ever want with no bad or radioactive leftovers - - only helium and heat. note that godes says that if the reaction is done properly, the nickel or palladium which are only used as a matrix to hold the hydrogen in one place, are not consumed in the reaction. for those who are skeptical, and i don ' t blame you for this a lot to comprehend, i recommend brillouin ' s web site ( www. brillouinenergy. com ) where you will find some reasonably comprehensible explanations and videos as to just how all this supposedly works. for those conversant with bose - einstein condensates, the molecular hamiltonian, heisenberg confinement energy, and the dense mathematics of nuclear physics there are papers there for you too. so what happens now? there is so much misunderstanding and skepticism about this phenomenon during the last 20 years", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6042957987434441, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:2437148e-00ac-4d84-b3cd-f9b22b323293>", "chunk_index": 1, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:51.182464"}
{"text": "condensates, the molecular hamiltonian, heisenberg confinement energy, and the dense mathematics of nuclear physics there are papers there for you too. so what happens now? there is so much misunderstanding and skepticism about this phenomenon during the last 20 years, it is likely that the mainstream media will not touch the story until some highly respected institution rolls out a machine that is too hot to touch, will run for months without any visible source of power, and will belch fire and brimstone on command. much to its credit, the first thing that brillouin energy says it is going to do with its new technology is to build a prototype boiler using its new heat source that would eventually replace the ones currently burning coal in our power stations. this is clearly a brilliant idea for swapping out old coal fired boilers for ones that run on a few cups of water would be a no - brainer for the world ' s electricity industry \u2013 provided of course they can be made to work reliably. brillouin energy says they have a contract with sri international to design and build a prototype of what they call a \" hot tube \" boiler. if the concept works well brillouin would license the technology to the world ' s boiler makers who presumably would work overtime replacing every fossil fuel fired boiler on the face of the earth. and that is just the start. tom whipple is a retired government analyst and has been following the peak oil issue for several years.", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6251139883450069, "token_count": 295, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:2437148e-00ac-4d84-b3cd-f9b22b323293>", "chunk_index": 2, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:51.184117"}
{"text": "july 22, 2004 los alamos, n. m., july 13, 2004 - - nearly five billion years ago, the giant gaseous planets jupiter and saturn formed, apparently in radically different ways. so says a scientist at the university of california ' s los alamos national laboratory who created exhaustive computer models based on experiments in which the element hydrogen was shocked to pressures nearly as great as those found inside the two planets. working with a french colleague, didier saumon of los alamos ' applied physics division created models establishing that heavy elements are concentrated in saturn ' s massive core, while those same elements are mixed throughout jupiter, with very little or no central core at all. the study, published in this week ' s astrophysical journal, showed that refractory elements such as iron, silicon, carbon, nitrogen and oxygen are concentrated in saturn ' s core, but are diffused in jupiter, leading to a hypothesis that they were formed through different processes. saumon collected data from several recent shock compression experiments that have showed how hydrogen behaves at pressures a million times greater than atmospheric pressure, approaching those present in the gas giants. these experiments - performed over the past several years at u. s. national labs and in russia - have for the first time permitted accurate measurements of the so - called equation of state of simple fluids, such as hydrogen, within the high - pressure and high - density realm where ionization occurs for deuterium, the isotope made of a hydrogen atom with an additional neutron. working with t. guillot of the observatoire de la cote d ' azur, france, saumon developed about 50, 000 different models of the internal structures of the two giant gaseous planets that included every possible variation permitted by astrophysical observations and laboratory experiments. \" some data from earlier planetary probes gave us indirect information about what takes place inside saturn and jupiter, and now we ' re hoping to learn more from the cassini mission that just arrived in saturn ' s orbit, \" saumon said. \" we selected only the computer models that fit the planetary observations. \" jupiter, saturn and the other giant planets are made up of gases, like the sun : they are about 70 percent hydrogen by mass, with the rest mostly helium and small amounts of heavier elements. therefore, their interior structures were hard to calculate because hydrogen ' s equation of state at high pressures wasn ' t well understood. saumon and guillot constrained their computer models with data from the deuterium experiments", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6096520276925048, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:2da1b080-9ee1-4d65-9510-88e8fec60a63>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:51.326508"}
{"text": "oct. 8, 2010 optical gyroscopes, also known as rotation sensors, are widely used as a navigational tool in vehicles from ships to airplanes, measuring the rotation rates of a vehicle on three axes to evaluate its exact position and orientation. prof. koby scheuer of tel aviv university ' s school of physical engineering is now scaling down this crucial sensing technology for use in smartphones, medical equipment and more futuristic technologies. working in collaboration with israel ' s department of defense, prof. scheuer and his team of researchers have developed nano - sized optical gyroscopes that can fit on the head of a pin - - and, more usefully, on an average - sized computer chip - - without compromising the device ' s sensitivity. these gyroscopes will have the ability to pick up smaller rotation rates, delivering higher accuracy while maintaining smaller dimensions, he says. the research was recently described in the journal optics express. \" conventional gyroscopes look like a box, and weigh two or three pounds, \" prof. scheuer explains. \" this is fine for an airplane, but if you ' re trying to fit a gyroscope onto a smaller piece of technology, such as a cellphone, the accuracy will be severely limited. \" with laser precision at the core of the new device are extremely small semi - conductor lasers. as the devices start to rotate, the properties of the light produced by the lasers changes, including the light ' s intensity and wavelength. rotation rates can be determined by measuring these differences. these lasers are a few tens - of - micrometers in diameter, as compared to the conventional gyroscope, which measures about 6 to 8 inches, says prof. scheuer. the device itself, when finished, will look like a small computer chip. measuring a millimeter by a millimeter ( 0. 04 inches by 0. 04 inches ), about the size of a grain of sand, the device can be built onto a larger chip that also contains other necessary electronics. prof. scheuer and his team of researchers are currently working on lab demonstrators of the device, which he predicts will be ready for testing in a few years ' time. tracking inside the body when available, the nano - gyroscopes will improve technologies that we use every day. when you rotate an iphone, for example, the screen adjusts itself accordingly. a nano - gyroscope would improve the performance of this feature and be sensitive", "subdomain_id": "subdomain_quantum_metrology", "similarity_score": 0.6407426418186372, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:91cddb7a-7c24-4003-9ed4-707b83071db5>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:51.338691"}
{"text": "jan. 22, 2012 scientists at the riken brain science institute ( bsi ) have uncovered mechanisms that help our brain to focus by efficiently routing only relevant information to perceptual brain regions. focus on what i am about to tell you! our complex modern world is filled with so many distractions - - flashing images on a television screen, blinking lights, blaring horns - - that our ability to concentrate on one thing at a time is of critical importance. how does our brain achieve this ability to focus attention? the answer is believed to lie in two distinct processes, referred to as \" sensitivity enhancement \" and \" efficient selection. \" sensitivity enhancement corresponds to improvements in how neurons in the cortex represent sensory information like sounds and lights, similar to the volume control or reception control on a television set. efficient selection is more like a filter, routing important sensory information to higher - order perceptual areas of the brain while suppressing disruptions from irrelevant information. with their research in neuron, justin gardner and colleagues at the riken bsi set out to put these hypotheses to the test and determine which of them plays a dominant role in perception. to do so, they measured brain activity using functional magnetic resonance imaging ( fmri ) while human subjects either focused their attention on a single visual location, or distributed their attention across multiple locations. to evaluate results, they used computational models about how brain signals should change based on how well subjects were able to focus their attention. what they found was that the computational model that best captured the brain activity in the human subjects was the one in which sensory signals were efficiently selected. the model also made a prediction about what kind of stimuli are particularly disruptive to our ability to focus, suggesting that signals which evoke high neural activity are preferentially passed on to perceptual areas of the brain : stimuli with high contrast that evoke large sensory responses, such as flashing lights or loud noises, can thus disrupt our ability to focus. while shedding light on the origins of perception, the results also hint at new ways of presenting information that capitalize on increasing neural activity to help our brains focus, promising applications in the development of critical information display technologies. the findings also offer insights into the causes of common attention - related disorders such as attention deficit hyperactivity disorder ( adhd ). other social bookmarking and sharing tools : note : if no author is given, the source is cited instead.", "subdomain_id": "subdomain_quantum_optics", "similarity_score": 0.6036451729117496, "token_count": 496, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:cfe78524-2f0a-48b1-9940-30ca1c28a295>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:51.345502"}
{"text": "1. a covering for the face or part of the face. 2. a likeness of a person ' s face. 3. an opaque border used to cover unwanted parts. 4. to conceal or cover. 5. to shield a person or object from something. someone who works and builds with brick, concrete blocks, stone, etc. trade name of a nonstructural building material, made of wood products and a binder, which creates a dense compressed board, which is useful where a smooth, flat flooring surface is needed. construction made from brick, cement block, or stone, which provides structural support as well as a decorative finish. masonry anchors attach masonry to other support structures, to other masonry, or attach additional pieces such as window frames, columns, etc. fasteners attach building elements to masonry and masonry ties hold masonry to other masonry. thee can be made of wire, sheet metal, galvanized rods, etc. some types of anchors are placed in the form prior to pouring of concrete. twist drill bit, with a carbide tip used for drilling holes in all types of masonry. concrete building blocks that are hollow. concrete, hollow - top block, which adds reinforcement around the outside of a building, when used in several courses of the wall. rebar is horizontally positioned in the hollow of the blocks, with concrete filling the remainder of the block, along the length of the wall. mix of portland cement, hydrated lime and other materials that trap air so that the water retention and workability of the cement are improved. joints between masonry units. block, mortar, or pre - cast concrete headers used for doors and windows in a masonry wall so that they match in appearance and usage. paint, containing acrylic emulsion or polyvinyl acetate, used on masonry surfaces. asphalt base, to which tar, sealing membranes, and other asphalt based materials will bond to provide a seal for moisture protection. steel reinforced stone, cement brick, concrete, etc. wall. symbols that identify different masonry types. blocks or brick, manufactured out of stone, cement, etc. or natural stone, which are, used as building units. thin layers of brick that are used for appearance purposes rather than structural support. wall comprised of brick, stone, cement, etc. sloped top cap that is preformed for use on masonry walls, allowing water to run off. mesh or heavy wire devices, which are set into the mortar between masonry units and then attached to an existing wall. simultaneous apprai", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6251708434752401, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:254b8357-8400-4cf2-a558-c91d29a04859>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:51.688777"}
{"text": "a local government to guide private and public development or by a developer on a specific project. development built according to a plan that includes commercial buildings, educational facilities, homes and community facilities. 1. one of a variety of quick drying, pasty cement for use when gluing tiles to a wall. 2. adhesive consisting of asphalt and nondrying oil. this type of adhesive must be heated to use. 3. construction adhesive, which is usually applied from a caulking gun. thin metal serrated edge blade with curved handle, used to spread mastic in ridges, which are spread out once the pieces are pressed together. 1. also spelled matte, it is a dull surface with no shine. 2. a flat coarse fabric made of woven hemp, rope, straw, etc. to be used as a floor cover. 3. structural surface of a flat, smooth, layer of asphalt or concrete. slab foundation for a structure, constructed of reinforced concrete. boards that are purposely milled so that they will fit tightly with each other, such as tongue and groove. mechanical drawing lines, which match a portion on one drawing with a portion on another drawing, usable with large building sections. boards whose edges are cut to fit tightly together. problem in a specific property that could affect the property ' s value or salability. information about a piece of property that could affect its salability and might change an individual ' s decision to purchase. a person who supplies materials used in the construction or repair of a building or other property. legal lien on property on behalf of an individual who has not been paid for material furnished in constructing property. a tax term introduced by the 1986 tax act, defined as year - round active involvement in the operations of a business activity on a regular, continuous and substantial basis. 1. that from which something takes shape, originates, develops, etc. 2. a die or mold used for casting. 3. rock or material, such as cement or mortar, in which pebbles, fossils, or other items are embedded. 4. set of items arranged in rows or columns to perform a specific function. also spelled mat, it is a dull surface with no shine. low sheen paint finish. the due date when a mortgage or a loan must be paid. heavy, long handled hammer which splits wood by either hitting it directly or using to hammer wedges into the wood. loan amount within 5 percent of the highest loan - to - value ratio allowable. master of business administration degree or mortgage", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.616782020235957, "token_count": 512, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:254b8357-8400-4cf2-a558-c91d29a04859>", "chunk_index": 2, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:51.695651"}
{"text": "the dew point is \u2018 the temperature to which a volume of humid air must be cooled \u2026 for water vapor to condense into liquid water \u2019, and is usually an early - morning or early - evening phenomenon in nature. ok, but, \u2018 what is the point of dew \u2019? that is a different question, but one which might have been answered by michael latakos et al. \u2013 at least in a botanical context. in their intriguing study they demonstrate that dew \u2013 \u2018 condensed water that forms on a solid surface \u2019 \u2013 is generated on the bark of understorey trees in a lowland forest in french guiana until early afternoon, because of the thermal properties of the trunks. this extensive window of hydration \u2013 up to 0. 69 mm of dewfall a day \u2013 is instrumental in prolonging photosynthesis, of epiphytic crustose lichens in particular. the team propose that this phenomenon may be a more general feature of forest habitats worldwide, and that this hitherto unrecognised mechanism of midday dew formation contributes to the water supply of most corticolous ( bark - dwelling ) organisms. nice work! in addition to the article, i also recommend michael proctor \u2019 s thoughtful commentary thereon. coincidentally, though, similar conclusions about the importance of dew were reached by khumbudzo maphangwa et al., who examined an altogether drier environment where \u2018 differential interception and evaporation of fog, dew and water vapour and elemental accumulation by lichens explain their relative abundance in a coastal desert \u2019. just as new hydrobotanical discoveries are made above ground, news of another, down below. using neutron tomography, ahmad moradi and co - workers have quantified and 3 - d visualized the water content in situ in the rhizospheres of chickpea ( cicer arietinum ), white lupin ( lupinus albus ) and maize ( zea mays ). finding that \u2013 counter - intuitively \u2013 soil water content increased towards the root surface for all three species, the team propose that plants modify the hydraulic properties of the rhizosphere \u2019 s soil in a way that improves water uptake under dry conditions. this \u2018 reservoir \u2019 of water can be viewed as a reserve that helps the plants overcome short periods of drought. hydraulic lift ( sorry, redistribution \u2013 ; rebecca neumann and zoe cardon ), anyone?", "subdomain_id": "subdomain_quantum_materials", "similarity_score": 0.6003879146091076, "token_count": 493, "source_dataset": "HuggingFaceFW/fineweb-edu", "source_id": "<urn:uuid:f8210b46-42ae-410d-9285-08ba874abe9d>", "chunk_index": 0, "filtering_threshold": 0.6, "created_at": "2025-12-26T09:27:52.151497"}