exchange clustering concepts topic last modified : 2006 - 02 - 09 by nino bilic this article covers some basic concepts about clustering and how clustering relates to microsoft® exchange server. the article ' s main purpose is to improve your understanding of clustering. resources and resource groups quorum disk resource how it all comes together the cluster service is a microsoft windows® service that can be used on certain versions of the windows operating systems. clustering is available in microsoft windows server™ 2003, enterprise edition, windows server 2003, datacenter edition, windows 2000 advanced server, and windows 2000 datacenter server operating systems. windows nt® server 4. 0, enterprise edition had clustering support starting with service pack 3 ( sp3 ), but this article does not provide details about windows nt server 4. 0 clustering. troubleshooting exchange server issues on the cluster server follows the same principles, in general, as troubleshooting non - clustered servers running exchange server. the following sections provide a high - level overview of clustering concepts. suppose you have a two node cluster. the same principles will apply for clusters of more than two nodes, but there is increased complexity as the number of nodes increases. so, in this example, start with node a and node b. in the microsoft implementation of clustering, node a and node b both have to be connected to some sort of shared storage. this shared storage must be on a scsi bus, either as direct connected storage or a storage area network ( san ). in a properly working cluster, only one node can have full access to any one shared disk at a time. so, if node a owns the shared storage, node b will not be able to see the same disk. this mode, where you do not share resources between nodes, is called a shared nothing clustering model. shared disk is essentially a resource for the cluster service. that resource will be in one of the resource groups. resource a resource is the single unit that can be administered or managed on the cluster. cluster resources include physical hardware devices such as disk drives and network cards, and logical items such as internet protocol ( ip ) addresses, applications, and application databases. each node in the cluster will have its own local resources, like a stand - alone server. however, the cluster also has common resources, such as a common data storage array and private cluster network. these common resources are accessible by each node in the cluster. a resource can be either online or offline. a resource is online when it is


key : " s : " = show synset ( semantic ) relations, " w : " = show word ( lexical ) relations display options for sense : ( gloss ) " an example sentence " - s : ( n ) undercut ( the material removed by a cut made underneath ) - s : ( n ) tenderloin, undercut ( the tender meat of the loin muscle on each side of the vertebral column ) - s : ( n ) undercut ( a notch cut in the trunk of tree in order to determine the direction of its fall ) - s : ( n ) cut, undercut ( ( sports ) a stroke that puts reverse spin on the ball ) " cuts do not bother a good tennis player " - s : ( n ) undercut ( a cut made underneath to remove material ) - s : ( v ) undersell, undercut ( sell cheaper than one ' s competition ) - s : ( v ) undercut ( cut away material from the underside of ( an object ) so as to leave an overhanging portion in relief ) - s : ( v ) undercut ( cut away the underpart of ) " undercut a vein of ore " - s : ( v ) undercut ( strike ( the ball ) in golf, tennis, or hockey obliquely downward so as to give a backspin or elevation to the shot ) - s : ( v ) undercut ( cut obliquely into ( a tree ) below the main cut and on the side toward which the tree will fall )


science fair project encyclopedia gilbert n. lewis his family moved to lincoln, nebraska when he was 9. he was homeschooled until age 9. he went to public school from age 9 to 14 and then he went to the university of nebraska, and three years later transferred to the harvard university where he showed an interest in economics, but concentrated in chemistry, getting his b. a. in 1896 and his ph. d. in 1899. his first published work, a study of thermochemical and electrochemical properties of amalgams, was based on his doctoral research and was published in 1898. after earning his ph. d., he stayed as an instructor for a year before taking a traveling fellowship, studying under the physical chemist wilhelm ostwald at leipzig and walter nernst at gottingen. he then returned to harvard as an instructor for three more years, and in 1904 left to become superintendent of weights and measures for the bureau of science of the philippine islands in manila. the next year he returned to cambridge when the massachusetts institute of technology ( mit ) appointed him to a faculty position, in which he had a chance to join a group of outstanding physical chemists under the direction of arthur amos noyes. he quickly rose in rank, becoming assistant professor in 1907, associate professor on 1908, and full professor in 1911. he left mit to become professor of physical chemistry and dean of the college of chemistry at the university of california, berkeley in 1912. in 1916, he formulated the idea that a covalent bond consisted of a shared pair of electrons and defined the term odd molecule when an electron is not shared. his ideas on chemical bonding were expanded upon by irving langmuir and became the inspiration for the studies on the nature of the chemical bond by linus pauling. in 1923, he formulated the electron - pair theory of acid - base reactions. in the so - called lewis theory of acids and bases, a " lewis acid " is an electron - pair acceptor and a " lewis base " is an electron - pair donor. students of chemistry learn about a notation system for the valence electrons which is known as the lewis dot structure. based on work by j. willard gibbs, it was known that chemical reactions proceeded to an equilibrium determined by the free energy of the substances taking part. lewis spent 25 years determining free energies of various substances. in 1923 he and merle randall published the results of this study and formalizing chemical thermodynamics. lewis was the first to produce a pure sample of deuter


3d printing, thus are able to see all the different possibilities for applications, from early concepting to full production prototypes. just a few years back, the costs for this technology were so high, it was really relegated to specific pockets in an organization and it didn ' t have much exposure beyond that small cadre of users. also, without actually seeing the technology at work, it ' s really hard to conceptualize how you print a physical object. i agree with you, rich, once you see the possibilities, it ' s pretty amazing. by experimenting with the photovoltaic reaction in solar cells, researchers at mit have made a breakthrough in energy efficiency that significantly pushes the boundaries of current commercial cells on the market. in a world that ' s going green, industrial operations have a problem : their processes involve materials that are potentially toxic, flammable, corrosive, or reactive. if improperly managed, this can precipitate dangerous health and environmental consequences. a quick look into the merger of two powerhouse 3d printing oems and the new leader in rapid prototyping solutions, stratasys. the industrial revolution is now led by 3d printing and engineers are given the opportunity to fully maximize their design capabilities, reduce their time - to - market and functionally test prototypes cheaper, faster and easier. bruce bradshaw, director of marketing in north america, will explore the large product offering and variety of materials that will help cad designers articulate their product design with actual, physical prototypes. this broadcast will dive deep into technical information including application specific stories from real world customers and their experiences with 3d printing. 3d printing is


securing virtual private networks ( vpn ), page 2 asymmetric encryption, or public key encryption, depends on a pair of keys called public key and private key ; hence the name. the keys are selected such that, if data is encrypted through key 1, it can be only decrypted through key 2 and vice versa. of the two keys, we tell about one to everybody and call it a public key. the other is kept private for decrypting and called a private key. for example, our e - mail account has a public e - mail address that we give to everyone we want to but we won ' t tell the password to anyone. suppose a person named linda is a broker and she gets a request mail by james anderson for buying some stock shares for his company. she performs all the arrangements and sends a confirmation mail to james. in the end, she sends a bill to him for the payment ; at this point, james completely denies that he has ever sent a mail to linda for any stock shares. now what should linda do? she is in extreme trouble because there is no clue to prove that james was the actual e - mailer. the solution is provided by the use of public key encryption ; if linda has encrypted the data by a public key, it can be decrypted only through linda ' s private key which should be told only to james, so when james replies to the confirmation mail for the shares, it is known for sure that the answering person is no other then james anderson and he is caught. this is source authentication. if we use the hashing scheme, such as md5, on our data and generate a hash value for it at the source computer and send it along the data to the target, the destination computer will also compute its hash code for the received data. if the hash generated by the destination is same as the one received by the source, our data integrity is preserved ; in other words, the data has reached its destination without any change or loss. this hash code is called a digital signature when sent with e - mail data. - data integrity - data origin authentication - replay prevention - limited traffic flow confidentiality replay prevention means that if somebody gets to know the keys by some means and resends your messages again or if someone gets to know the user name and password of your account, he or she can directly learn all your important business transactions and deals with others and can enjoy full authority to make other deals with them on your


and resends your messages again or if someone gets to know the user name and password of your account, he or she can directly learn all your important business transactions and deals with others and can enjoy full authority to make other deals with them on your account using your name. ike is a mechanism in ipsec where we exchange the key. it is a hybrid protocol that implements oakley and skeme key exchanges inside the isakmp framework. while ike can be used with other protocols, its initial implementation is with the ipsec protocol. ike provides authentication of the ipsec peers, negotiates ipsec keys, and negotiates ipsec security associations. the main features of ike are as follows : - negotiates policy to protect communication - authenticated diffie - hellman key exchange - negotiates ( possibly multiple ) security associations ( sa ) for ipsec. diffie - hellman is a public - key cryptography protocol that allows two parties to establish a shared secret over an unsecured communication channel. diffie - hellman is used within ike to establish session keys. 768 - bit and 1024 - bit diffie - hellman groups are supported. security association ( sa ) combines the agreed upon principles for vpn communication. this is done by ike. the secret key exchange is the main process so that the dependent data to be delivered is secured. isakmp + oakley is the ike policy that we define to start the encryption process. the internet security association and key management protocol ( isakmp ) is a protocol framework that defines payload formats, the mechanics of implementing a key exchange protocol, and the negotiation of a security association. oakley is a key exchange protocol that defines how to derive authenticated keying material. skeme is a key exchange protocol that defines how to derive authenticated keying material, with rapid key refreshment. md5 ( message digest 5 ) is a hash algorithm used to authenticate packet data. hmac is a variant that provides an additional level of hashing. the data encryption standard ( des ) is used to encrypt packet data. ike implements the 56 - bit des - cbc with explicit iv standard. authentication header is used for data integrity and source authentication whereas encapsulating security protocol is used for confidentiality.


find the same theory repeated with modifications by many writers in the present day, who, without adhering closely to kantian principles, adopt his general conception of the limits of knowledge. to such writers science seems to be confined to the task of tracing out the lines of natural necessity by which one phenomenon, or phase of existence, is bound to another ; and the possibility of escape from this iron circle of causation is supposed to be opened up by the revolt of human hearts against it. thus the feeling of inconsistency between the conditions of finite existence and the obligations laid upon us by our spiritual nature, the demand of the soul for a good more complete and enduring than any of the changing objects of sense, or the aspiration after an ideal beauty which is never adequately realised in the worldare regarded as a sufficient warrant for casting aside the ordinary tests of credibility and basing belief upon the will to believe. in many different ways the will, or the heart, or the imagination, is supposed to emancipate us from the limitations of sense and experience, and to put us in relation to ends and objects which cannot be brought within the scope of science. now it is easy to see that the two theories or classes of theories, represented by aristotle and kant, are diametrically opposed to each other, and it is instructive to draw out the points of contrast between them. with kant science is confined to the discovery of the laws which determine the co - existence and succession of objects and events in the finite world of experience, and it is only through the moral consciousness and the practical faith which that consciousness brings with it that we escape from the limits of this system of necessity, and rise to the idea of a spiritual god who rules over a free kingdom of spiritual beings. with aristotle, on the other hand, moral practice is the hampered activity of reason, working with a matter which can never be perfectly subdued or determined by it, exercising itself in a medium which is exposed to the inroads of a necessity that cones not from within but from without, not from itself, but from nature and circumstance : while it is science which emancipates reason from this foreign yoke, and raises it to a consciousness of all things in their ideal principles, which is also a consciousness of their unity with the mind that knows them : for, as aristotle says, in the case of things without matter, the knower and the known are one. thus it is only the mind which sees the essential forms of thingstheir final


and reaction of elements which are not themselves subordinated to any pervading unity. and the darwinian theory, many as are the applications of the idea of purpose to which it has led, is itself an attempt to carry the idea of an external necessity, resulting from the relations of the organism and the environment, into the explanation of those very phenomena which were once thought to be the clearest evidences of design. but, in the second place, there is a better way of proving the limited and provisional character of the ordinary scientific view of nature, as a system of external necessity ; and kant himself, though he maintained that view, and indeed, gave it a fuller and more distinctive philosophical expression than anyone before him, was also the first to supply the conclusive means of refuting it. for, while he treated the world of experience as a system of objectswhich are external to each other in space, and pass through successive phases in time, according to necessary laws of coexistence and successionhe showed also that this world of necessity stands in essential relation to the unity of the self that knows it. hence, any explanation of the world, or of any object in it, which does not take account of this relation, must be regarded as abstract and imperfect. thus the external necessity which characterises the objective world when we regard it as complete in itself ( as it is generally regarded by science ), must receive a new interpretation when we recognise that it cannot be separated from the unity of the intelligence. when we rise above the abstractions of the ordinary consciousness and of science, and take a complete or concrete view of the facts, we see that this external necessity never exists apart from an identity which manifests itself in it and controls it. this identity beyond difference, indeed, was recognised by kant only in the form of an ideal of reason which cannot be realised in experience, or, in his language, of a regulative idea, which cannot be treated as constitutive. but this view implies an imperfect conception of the unity of selfconsciousness, and is quite inconsistent with kant ' s own conception of the relativity of objects to that unity. for, if the object in its externality be an abstraction which requires an ideal principle of identity to complete itif, in other words, the object always has a subjective unity underlying all its differenceswe can no longer admit that kant ' s categories of the understanding are the highest principles we can apply to the contents of our experience. if, therefore, the special


to look beyond it to an intelligible world, in which all things are determined according to the law of liberty, and to a divine intelligence which orders all things according to that law. but one of the necessary presuppositions of this view has already disappeared when we have rejected the conception of the objective world as a world of necessity. and the other necessary presupposition must also disappear, when we recognise that the subjective unity of self - consciousness cannot be severed from the objective consciousness of the world in space and time. the relativity of object and subject to each other implies that the unity of the intelligence must be found also in the object ; but it also implies that the intelligence or conscious self, in seeking to realise itself in the object, is only bringing to light what the true nature of the object is. hence, we cannot suppose that the aspirations of the soul or the obligations of the will can carry us into a new region absolutely separated from that phenomenal world, which is the object of our knowledge. on the contrary, the practical must be viewed as continuous with the theoretical life, and it mist be recognised that, if the former goes farther than the latter, it is still on the same road. the good cannot he opposed to the true ; for they are only different aspects of the relation of the same self to the same all - embracing whole, in which the self finds its objective counterpart. thus the contrast of knowing and willing cannot be treated as an absolute one, so soon as we discern that in knowing we are coming to the consciousness of self as well as of the objective world, and that in action we are realising an end which is involved in the nature of the world as well as in our own nature. it is true that in both cases, in knowledge as in action, the universality of the principle that manifests itself in our lives is at first hidden from us by the conditions of its progressive manifestation. what we know seems to be only the particular things with which our senses bring us into contact ; what we will seems to be only the particular objects which excite our desires. we do not reflect that all known objects already have taken their place in the one world to which all that is knowable by the one self must belong ; nor that all objects of desire must be sought sub ratione boni, as the satisfaction of a self which, as it is a unity to which all ends are related, cannot be satisfied with anything but the whole. thus through all the stages of their development, the


and beings. in this there is obviously manifested the influence of a false ideal of knowledge ; for, even if we conceived the stellar motions as he did, that is to say, as circular motions absolutely continuous and regular, or only irregular in so far as many spheres are concerned in the movement of one body, this absence of complexity would seem to us to involve that there is less, and not more, need for a spiritual principle to explain them. in both cases, however, in astronomy as in mathematics, we are really dealing with what is general and abstractwith aspects of the existence of material objects, the exactness of our knowledge of which is dependent on the fact, that we consciously omit, or unconsciously neglect, their relations to other parts or elements of reality. in like manner, the comparative exactness of physical science in general is at least partly due to the fact that we regard its objects merely as material things, and omit altogether to take into account their relations to life and mind. hence, though this kind of exactness seems to diminish as we rise in the scale of the sciences from physics to chemistry, from chemistry to biology, from biology to psychology, this does not mean that we are passing from that which is more to that which is less intelligible ; rather it means the reverse of this. it means that we are bringing our science nearer and nearer to the complex whole to which these abstracted elements belong, and, therefore, are leaving less and less to take its place with the accidental or inexplicable. it is true that, as we advance, just because we are leaving the region of the abstract, we are brought into contact with greater difficulties. the unexplained remainder, that is, the numerous objects and events which, after all that the special sciences can do, are still incompletely accounted forall this apparently accidental element in life does not press itself upon our notice, while we are dealing with the abstractions of mathematics, or with what we may call the natural abstraction of the motions of the heavenly bodies. even in physics and chemistry we are not much troubled with the consciousness of it, because in these sciences we are satisfied with finding the causes or conditions of the particular phenomena, and are not embarrassed by the thought of any general purpose or teleological unity that binds all the particular phenomena together as elements in one whole. but biology brings with it the conceptions of organic unity and evolution ; it exhibits to us, in the plant and still more in the animal,


found in the work of those logicians, philosophers and mathematicians who made such assumptions. in 1902, russell discovered that a version the contradiction was expressible in the logical system developed in volume i of gottlob frege ’ s grundgesetze der arithmetik, one of the central works in the late - 19th and early - 20th century revolution in logic. in frege ’ s philosophy, a class is understood as the “ extension ” or “ value - range ” of a concept. concepts are the closest correlates to properties in frege ’ s metaphysics. a concept is presumed to exist for every specifiable condition or predicate. thus, there is a concept of being a class that does not fall under its defining concept. there is also a class defined by this concept, and it falls under its defining concept just in case it does not. russell wrote to frege concerning the contradiction in june of 1902. this began one of the most interesting and discussed correspondences in intellectual history. frege immediately recognized the disastrous consequences of the paradox. he did note, however, that the properties version of the paradox was solved in his philosophy by his distinction between levels of concepts. for him, concepts are understood as functions from arguments to truth - values. some concepts, “ first - level concepts ”, take objects as arguments, some concepts, “ second - level concepts ” take these functions as arguments, and so on. thus, a concept can never take itself as argument, and the properties version cannot be formulated. however, classes, or extensions or concepts, were all understood by frege to be of the same logical type as all other objects. the question does arise, then, for each class whether it falls under its defining concept. when he received russell ’ s first letter, the second volume of frege ’ s grundgesetze was already in the latter stages of the publication process. frege was forced to quickly prepare an appendix in response to the paradox. frege considers a number of possible solutions. the conclusion he settles on, however, is to weaken the class abstraction principle in the logical system. in the original system, one could conclude that an object is in a class if and only if the object falls under the concept defining the class. in the revised system, one can conclude only that an object is in a class if and only if the object falls under the concept defining the class and the object is not identical to the class in question. this blocks the class version of the paradox.


that the property of being a cat is a cat. however, different thinkers explain the justification for the type - division in different ways. russell even gave different explanations at different parts of his career. for his part, the justification for frege ’ s division of different levels of concepts derived from his theory of the unsaturatedness of concepts. concepts, as functions, are essentially incomplete. they require an argument in order to yield a value. one cannot simply predicate one concept of a concept of the same type, because the argument concept still requires its own argument. for example, while it is possible to take the square root of the square root of some number, one cannot simply apply the function square root to the function square root and arrive at a value. conservatism about properties. another possible solution to the paradox of properties would involve denying that a property exists corresponding to any specifiable conditions or well - formed predicate. of course, if one eschews metaphysical commitment to properties as objective and independent entities altogether, that is, if one adopts nominalism, then the paradoxical question is avoided entirely. however, one does not need to be quite so extreme in order to solve the antinomy. the higher - order logical systems developed by frege and russell contained what is called the comprehension principle, the principle that for every open formula, no matter how complex, there exists as entity a property or concept exemplified by all and only those things that satisfy the formula. in effect, they were committed to attributes or properties for any conceivable set of conditions or predicates, no matter how complex. however, one could instead adopt a more austere metaphysics of properties, only granting objective existence to simple properties, perhaps including redness, solidity and goodness, etc. one might even allow that such properties can possibly apply to themselves, e. g. that goodness is good. however, on this approach one would deny the same status to complex attributes, e. g. the so - called “ properties ” as having - seventeen - heads, being - a - cheese - made - england, having - been - written - underwater, etc. it is simply not the case that any specifiable condition corresponds to a property, understood as an independently existing entity that has properties of its own. thus, one might deny that there is a simple property being - a - property - that - does - not - apply - to - itself. if so, one can avoid the paradox simply by adopting a


and only if the formula a is stratified, that is, if there is some assignment of natural numbers to the variables in a such that for each occurrence of the class membership sign, the variable preceding the membership sign is given an assignment one lower than the variable following it. this blocks russell ’ s paradox, because the formula used to define the problematic class has the same variable both before and after the membership sign, obviously making it unstratified. however, it has yet to be determined whether or not the resulting system, which quine called “ new foundations for mathematical logic ” or nf for short, is consistent or inconsistent. aussonderung : a quite different approach is taken in zermelo - fraenkel ( zf ) set theory. here too, a restriction is placed on what sets are supposed to exist. rather than taking the “ top - down ” approach of russell and frege, who originally believed that for any concept, property or condition, one can suppose there to exist a class of all those things in existence with that property or satisfying that condition, in zf set theory, one begins from the “ bottom up ”. one begins with individual entities, and the empty set, and puts such entities together to form sets. thus, unlike the early systems of russell and frege, zf is not committed to a universal set, a set including all entities or even all sets. zf puts tight restrictions on what sets exist. only those sets that are explicitly postulated to exist, or which can be put together from such sets by means of iterative processes, etc., can be concluded to exist. then, rather than having a naive class abstraction principle that states that an entity is in a certain class if and only if it meets its defining condition, zf has a principle of separation, selection, or as in the original german, “ aussonderung “. rather than supposing there to exist a set of all entities that meet some condition simpliciter, for each set already known to exist, aussonderung tells us that there is a subset of that set of all those entities in the original set that satisfy the condition. the class abstraction principle then becomes : if set a exists, then for all entities x in a, x is in the subset of a that satisfies condition c if and only if x satisfies condition c. this approach solves russell ’ s paradox, because we cannot simply assume that there is a set of all sets that are


to qpd. i use krohn - hite single - ended input 8 - pole low - pass bessel filters with cutoff at 1. 5 khz for x, y, sum and piezo signal. even though the filters have cutoff at 1. 5 khz but they affect the power - spectrum generated corner frequency even at 500hz. i use x - signal from on - track to generate the power - spectrum. to study this behavior i generate an interferogram of sound with frequency components from 10 to 1600 hz with whitesoundmain program written in labview v9 and produce it at the output of soundcard of one computer. i feed this sound signal into mic - input of another computer and read the interferogram with noise investigator and helper program written in labview v9 ( i used the same programs and method to study structural resonance of optical setups ). see the slide show for more information. i record the data ; when there was no filter between the output and input ( signal goes straight from one computer to another ) and when there is a filter between ( signal goes through the filter before input ). the result is as expected : graph is a power spectrum of input interferogram ; without filter ( red curve ) it is a square function over 1600hz, with filter ( white curve ) frequency starts rolling off after 360hz. this means with filter on power - spectrum taken at frequencies higher than 360hz will report false corner frequency ( low corner frequency will report low stiffness ). fix of this problem is simple ; remove the filter when doing power - spectrum. now we have collected all the essential information about the active components of our setup, it is time to proceed for calibration. optical tweezers calibration is a tedious task, but it is done only once, if no major changes are made to the optical path or components downstream from the objective. optical tweezers calibration schematics in image shows all the parameters and programs i use. to determine the force exerted by the trap i need to know two parameters : stiffness and displacement. calibration of trap stiffness the stiffness of the trap is proportional to the corner frequency of the overdamped trapped free bead ’ s brownian motion. basically trap stiffness depends on two parameters : corner frequency and stokes drag coefficient. there are multiple ways to determine the trap stiffness but we do it power - spectrum way. when a bead is trapped the mechanics


the advanced encryption standard ( aes ) computer security standard is a symmetric block cipher that encrypts and decrypts 128 - bit blocks of data. standard key lengths of 128, 192, and 256 bits may be used. the algorithm consists of four stages that make up a round which is iterated 10 times for a 128 - bit length key, 12 times for a 192 - bit key, and 14 times for a 256 - bit key. the first stage “ subbytes ” transformation is a non - linear byte substitution for each byte of the block. the second stage “ shiftrows ” transformation cyclically shifts ( permutes ) the bytes within the block. the third stage “ mixcolumns ” transformation groups 4 - bytes together forming 4 - term polynomials and multiplies the polynomials with a fixed polynomial mod ( x ^ 4 + 1 ). the fourth stage “ addroundkey ” transformation adds the round key with the block of data. in most ciphers, the iterated transform ( or round ) usually has a feistel structure. typically in this structure, some of the bits of the intermediate state are transposed unchanged to another position ( permutation ). aes does not have a feistel structure but is composed of three distinct invertible transforms based on the wide trial strategy design method. the wide trial strategy design method provides resistance against linear and differential cryptanalysis. in the wide trail strategy, every layer has its own function : - the linear mixing layer : guarantees high diffusion over multiply rounds - the non - linear layer : parallel application of s - boxes that have the optimum worst - case non - linearity properties. - the key addition layer : a simple xor of the round key to the intermediate state - plaintext refers to the data to be encrypted. ciphertext refers to the data after going through the cipher as well as the data that will be going into the decipher. - the state is an intermediate form of the cipher or decipher result usually displayed as a rectangular table of bytes with 4 rows and 4 columns. vocal ’ s embedded software libraries include a complete range of etsi / itu / ieee compliant algorithms, in addition to many other standard and proprietary algorithms. our software is optimized for execution on ansi c and leading dsp architectures ( ti, adi, amd, arm, mips, ceva, lsi logic zsp, etc. ). these libraries are modular and can be executed as


physicists announce antimatter discoveryby steve koppes mother nature likes matter better than antimattera preference physicists technically refer to as charge - parity violation. first observed in 1964 by james cronin and val fitch, the indirect cp violation they studied won them the 1980 nobel prize in physics. since then, theorists have worked to devise a model of physics that could account for cp violation, but there was no independent evidence to test the models against. nothing, that is, until wednesday, feb. 24, when chicago graduate student peter shawhan announced at a fermilab seminar the discovery of direct cp violation, an entirely new type of inequality between matter and antimatter. its an uncharted territory, said bruce winstein, the samuel allison distinguished service professor in physics, who headed up the 21 - year effort that led to the discovery. for 34 years weve had one measurement of cp violation, just one manifestation of it. this is the first new one since that time. in 1964 at brookhaven national laboratory, cronin and fitch observed indirect cp violation, the unbalanced mixing of neutral subatomic kaon particles with their charged antiparticles. the fermilab team has observed direct cp violation. to study the process, the fermilab team produces enormous quantities of kaons with the worlds highest - energy proton beam at fermilabs tevatron accelerator. kaons decay into other types of particles within a tiny fraction of a second after they are produced, so the ktev detectors must identify and measure their position and energy quickly. the experiment, called kaons at the tevatron at fermilab, is a collaboration involving 80 physicists from 12 institutions. about 15 of the ktev physicists are from the university ; eight of these chicago scientists analyzed the data that led to the feb. 24 announcement. winstein began experimenting with cp violation in 1978. construction on the latest experiment, the third in a successively more accurate series, began in 1992. the experiment began running 24 hours a day in late 1996. its an extremely high - precision experiment, said shawhan, the senior chicago graduate student on the project. first we have to design the experiment well. then we have to be very certain that we understand our detector and our analysis in greater detail than most other high - energy experiments because were looking for such a subtle effect. a great deal of work has gone into that effort. the experiment attempts to measure a quantity called epsilon prime divided by epsilon. if


our detector and our analysis in greater detail than most other high - energy experiments because were looking for such a subtle effect. a great deal of work has gone into that effort. the experiment attempts to measure a quantity called epsilon prime divided by epsilon. if the quantity had turned out to be zero, it would have verified the superweak model of cp violation. a nonzero value would favor the standard model, to which most physicists subscribe. the result that shawhan announced feb. 24 was 0. 00280 with an error of 0. 00041. this eliminates the superweak model as the sole explanation for cp violation, but a problem remains. the number that we got was larger than most theorists had predicted, said edward blucher, assistant professor in physics at chicago and a member of the fermilab team for five years. blucher and his students, jim graham and val prasad, along with graduate student colin bown, postdoctoral scientists rick kessler and sasha glazov, and former member aaron roodman, made up the chicago team for this analysis. the european laboratory for particle physics, cern, in switzerland, found evidence for direct cp violation before the fermilab team, but the cern measurements were less precise. it wasnt definitive evidence, winstein said. the chicago researchers initially reacted to the latest result with mixed emotions. there was a mixture of jubilation, shock and a feeling of, oh my god, did we screw up, all at once, winstein said. but there is no question about the latest fermilab results, cronin said : its final. the experiment has doubled scientific knowledge about cp violation independent of any theory or speculation, said cronin, professor in physics and astronomy & astrophysics at chicago. this wonderful discovery is a beautiful surprise, cronin said. its just wonderful because i dont think anybody expected it. thats what makes it especially delicious.


waste, reducing the need for more virgin resources, and no more plastic into the environment! with clean and abundant cold fusion energy, we can stop the pollution from fossil fuels and the end resource wars limited supplies engender. carbon - burning steam power revolutionized farming in the 19th century. nickel - hydrogen exothermic reaction steam power can revolutionize world agriculture in the 21rst century. in the ancient mediterranean villages where philosophy and science began, problems associated with increasing population in were taken care of by shipping off a portion of the tribe to a new location, sometimes forcefully, and founding a new colony. 21rst century humans do not have that same opportunity. there is no ‘ unknown ’ area on earth to expand into. moon base 2020? not likely without cold fusion energy. on earth, there is only what we choose to programas nature. ‘ nature ’ can only be a work of art with the participation of all. why should we care about the wildlife of this world? one of the first philosophers in the greek world was empedocles. he lived around 450bc and came from the island of sicily. in one of his surviving fragments of writing, he relates to his student pausanias the importance of listening carefully to the words his teacher empedocles is saying. and why is listening to the teacher empedocles ’ words so important? “ if you press them down underneath your dense - packed diaphragm and oversee them with good will and with pure attention to the work, they will all without the slightest exception stay with you for as long as you live. and, from them, you will come to possess many other things. for they grow, each according to its own inner disposition, in whatever way their but if you reach out instead after other kinds of things – after the ten thousand worthless things that exist among humans, blunting their cares – then you can be sure they will only too gladly leave you with the circling of time, longing to return to their own dear kind. for you need to know that everything has intelligence and a share empedocles 450bc translated by peter kingsley inreality cold fusion now! reality by peter kingsley www. peterkingsley. org earth policy institute you can help animals and birds in your neighborhood by providing fresh drinking water, putting bird seed in feeders, and plant indigenous to feed local wildlife. refrain from toxic chemical use in and around your home, and recycle even the tiniest of plastic pieces. to learn more about endangered species


such as this is never a mushroom growth, nor does it usually spring full grown from the mind of any single man. always a number of minds are very near a truth before any one mind fully grasps it. pre - eminently true is this of the doctrine of the conservation of energy. not faraday alone, but half a dozen different men had an inkling of it before it gained full expression ; indeed, every man who advocated the undulatory theory of light and heat was verging towards the goal. the doctrine of young and fresnel was as a highway leading surely on to the wide plain of conservation. the phenomena of electro - magnetism furnished another such highway. but there was yet another road which led just as surely and even more readily to the same goal. this was the road furnished by the phenomena of heat, and the men who travelled it were destined to outstrip their fellow - workers ; though, as we have seen, wayfarers on other roads were within hailing distance when the leaders passed the mark. in order to do even approximate justice to the men who entered into the great achievement, we must recall that just at the close of the eighteenth century count rumford and humphry davy independently showed that labor may be transformed into heat ; and correctly interpreted this fact as meaning the transformation of molar into molecular motion. we can hardly doubt that each of these men of genius realized — vaguely, at any rate — that there must be a close correspondence between the amount of the molar and the molecular motions ; hence that each of them was in sight of the law of the mechanical equivalent of heat. but neither of them quite grasped or explicitly stated what each must vaguely have seen ; and for just a quarter of a century no one else even came abreast their line of thought, let alone passing it. but then, in 1824, a french philosopher, sadi carnot, caught step with the great englishmen, and took a long leap ahead by explicitly stating his belief that a definite quantity of work could be transformed into a definite quantity of heat, no more, no less. carnot did not, indeed, reach the clear view of his predecessors as to the nature of heat, for he still thought it a form of " imponderable " fluid ; but he reasoned none the less clearly as to its mutual convertibility with mechanical work. but important as his conclusions seem now that we look back upon them with clearer vision, they made no impression whatever upon his contemporaries. carnot ' s


this is a visualization of drug molecules ( " parade day - like balloons " ) in a simulated attack of the ribbon - like protein fibrils that are believed to be the cause of alzheimer ’ s disease. click here to see more amazing supercomputer simulations. | image courtesy of ornl. talk about some amazing origami. imagine, if you can, taking a sheet of paper or two and folding them together with such tight precision that instead of creating a crane or a cat, you actually produce a working machine. then imagine trying to do so while caught in the middle of a football crowd, being bumped and jostled from many directions. cells do this every second, assembling molecular machines known as proteins by folding long strings of amino acids. proteins perform a variety of different functions, such as transmitting cellular signals and speeding essential chemical reactions. that makes protein folding of great interest to scientists, especially since badly formed proteins might lead to diseases like alzheimer ’ s, creutzfeldt - jakob disease, cystic fibrosis and others. however, researchers have been unable to predict how proteins fold together with such precision, especially while being battered by fluid constantly moving inside cells. that is until now. a team of researchers from the university of pittsburgh and the energy department ' s oak ridge national laboratory recently developed a computational technique that helps understand the process of protein folding. specifically, the method, known as quasi - anharmonic analysis ( qaa ) provides insight into the intermediate steps that take place as a protein folds. as in origami, certain folds are more important than others. some may have little impact, while others will be critical in determining the final form ( whether a bat or a hat or a crane or a cat ). better knowledge of protein folding could in turn provide more insight into the diseases associated with malformed proteins, as mentioned above, and potential fixes for those malformations. that in turn could lead to new possibilities for new treatments. the team of researchers developed and improved their protein folding simulations, thanks to ornl ’ s first - class supercomputing facilities. much of the data they checked the model against came from a technique known as neutron scattering. ornl is the world ’ s premiere center for neutron scattering research, thanks to its spallation neutron source and high - flux isotope reactor. ornl researchers also search for insights in many related areas, such as modeling the mechanism of alzheimer ’ s disease at the molecular scale. inspiration and insight folding together with outstanding equipment


reality is the state of things as they actually exist, rather than as they may appear or might be imagined. in a wider definition, reality includes everything that is and has been, whether or not it is observable or comprehensible. a still more broad definition includes everything that has existed, exists, or will exist. philosophers, mathematicians, and other ancient and modern thinkers, such as aristotle, plato, frege, wittgenstein, and russell, have made a distinction between thought corresponding to reality, coherent abstractions ( thoughts of things that are imaginable but not real ), and that which cannot even be rationally thought. by contrast existence is often restricted solely to that which has physical existence or has a direct basis in it in the way that thoughts do in the brain. reality is often contrasted with what is imaginary, delusional, ( only ) in the mind, dreams, what is false, what is fictional, or what is abstract. at the same time, what is abstract plays a role both in everyday life and in academic research. for instance, causality, virtue, life and distributive justice are abstract concepts that can be difficult to define, but they are only rarely equalled with pure delusions. both the existence and reality of abstractions is in dispute : one extreme position regard them as mere words, another position regard them as higher truths than less abstract concepts. this disagreement is the basis of the philosophical problem of universals. reality, world views, and theories of reality a common colloquial usage would have reality mean " perceptions, beliefs, and attitudes toward reality, " as in " my reality is not your reality. " this is often used just as a colloquialism indicating that the parties to a conversation agree, or should agree, not to quibble over deeply different conceptions of what is real. for example, in a religious discussion between friends, one might say ( attempting humor ), " you might disagree, but in my reality, everyone goes to heaven. " reality can be defined in a way that links it to world views or parts of them ( conceptual frameworks ) : reality is the totality of all things, structures ( actual and conceptual ), events ( past and present ) and phenomena, whether observable or not. it is what a world view ( whether it be based on individual or shared human experience ) ultimately attempts to describe or map. certain ideas from physics, philosophy, sociology, literary criticism, and other fields shape


phenomena, whether observable or not. it is what a world view ( whether it be based on individual or shared human experience ) ultimately attempts to describe or map. certain ideas from physics, philosophy, sociology, literary criticism, and other fields shape various theories of reality. one such belief is that there simply and literally is no reality beyond the perceptions or beliefs we each have about reality. such attitudes are summarized in the popular statement, " perception is reality " or " life is how you perceive reality " or " reality is what you can get away with " ( robert anton wilson ), and they indicate anti - realism – that is, the view that there is no objective reality, whether acknowledged explicitly or not. many of the concepts of science and philosophy are often defined culturally and socially. this idea was elaborated by thomas kuhn in his book the structure of scientific revolutions ( 1962 ). the social construction of reality, a book about the sociology of knowledge written by peter l. berger and thomas luckmann, was published in 1966. on the one hand, ontology is the study of being, and the central topic of the field is couched, variously, in terms of being, existence, " what is ", and reality. the task in ontology is to describe the most general categories of reality and how they are interrelated. if a philosopher wanted to proffer a positive definition of the concept " reality ", it would be done under this heading. as explained above, some philosophers draw a distinction between reality and existence. in fact, many analytic philosophers today tend to avoid the term " real " and " reality " in discussing ontological issues. but for those who would treat " is real " the same way they treat " exists ", one of the leading questions of analytic philosophy has been whether existence ( or reality ) is a property of objects. it has been widely held by analytic philosophers that it is not a property at all, though this view has lost some ground in recent decades. on the other hand, particularly in discussions of objectivity that have feet in both metaphysics and epistemology, philosophical discussions of " reality " often concern the ways in which reality is, or is not, in some way dependent upon ( or, to use fashionable jargon, " constructed " out of ) mental and cultural factors such as perceptions, beliefs, and other mental states, as well as cultural artifacts, such as religions and political movements, on up to the vague notion of a common cultural world view, or weltanschau


artifact. a correspondence theory of knowledge about what exists claims that " true " knowledge of reality represents accurate correspondence of statements about and images of reality with the actual reality that the statements or images are attempting to represent. for example, the scientific method can verify that a statement is true based on the observable evidence that a thing exists. many humans can point to the rocky mountains and say that this mountain range exists, and continues to exist even if no one is observing it or making statements about it. the nature of being is a perennial topic in metaphysics. for, instance parmenides taught that reality was a single unchanging being, whereas heraclitus wrote that all things flow. the 20th century philosopher heidegger thought previous philosophers have lost sight the question of being ( qua being ) in favour of the questions of beings ( existing things ), so that a return to the parmenidean approach was needed. an ontological catalogue is an attempt to list the fundamental constituents of reality. the question of whether or not existence is a predicate has been discussed since the early modern period, not least in relation to the ontological argument for the existence of god. existence, that something is, has been contrasted with essence, the question of what something is. since existence without essence seems blank, it associated with nothingness by philosophers such as hegel. nihilism represents an extremely negative view of being, the absolute a positive one. the question of direct or " naive " realism, as opposed to indirect or " representational " realism, arises in the philosophy of perception and of mind out of the debate over the nature of conscious experience ; the epistemological question of whether the world we see around us is the real world itself or merely an internal perceptual copy of that world generated by neural processes in our brain. naive realism is known as direct realism when developed to counter indirect or representative realism, also known as epistemological dualism, the philosophical position that our conscious experience is not of the real world itself but of an internal representation, a miniature virtual - reality replica of the world. timothy leary coined the influential term reality tunnel, by which he means a kind of representative realism. the theory states that, with a subconscious set of mental filters formed from their beliefs and experiences, every individual interprets the same world differently, hence " truth is in the eye of the beholder ". his ideas influenced the work of his friend robert anton wilson. abstract objects and mathematics the status of abstract entities, particularly


their beliefs and experiences, every individual interprets the same world differently, hence " truth is in the eye of the beholder ". his ideas influenced the work of his friend robert anton wilson. abstract objects and mathematics the status of abstract entities, particularly numbers, is a topic of discussion in mathematics. in the philosophy of mathematics, the best known form of realism about numbers is platonic realism, which grants them abstract, immaterial existence. other forms of realism identify mathematics with the concrete physical universe. some approaches are selectively realistic about some mathematical objects but not others. finitism rejects infinite quantities. ultra - finitism accepts finite quantities up to a certain amount. constructivism and intuitionism are realistic about objects that can be explicitly constructed, but reject the use of the principle of the excluded middle to prove existence by reductio ad absurdum. the traditional debate has focused on whether an abstract ( immaterial, intelligible ) realm of numbers has existed in addition to the physical ( sensible, concrete ) world. a recent development is the mathematical universe hypothesis, the theory that only a mathematical world exists, with the finite, physical world being an illusion within it. an extreme form of realism about mathematics is the mathematical multiverse hypothesis advanced by max tegmark. tegmark ' s sole postulate is : all structures that exist mathematically also exist physically. that is, in the sense that " in those [ worlds ] complex enough to contain self - aware substructures [ they ] will subjectively perceive themselves as existing in a physically ' real ' world ". the hypothesis suggests that worlds corresponding to different sets of initial conditions, physical constants, or altogether different equations should be considered real. the theory can be considered a form of platonism in that it posits the existence of mathematical entities, but can also be considered a mathematical monism in that it denies that anything exists except mathematical objects. the problem of universals is an ancient problem in metaphysics about whether universals exist. universals are general or abstract qualities, characteristics, properties, kinds or relations, such as being male / female, solid / liquid / gas or a certain colour, that can be predicated of individuals or particulars or that individuals or particulars can be regarded as sharing or participating in. for example, scott, pat, and chris have in common the universal quality of being human or humanity. the realist school claims that universals are real – they exist and are distinct from the particulars that instantiate them


sharing or participating in. for example, scott, pat, and chris have in common the universal quality of being human or humanity. the realist school claims that universals are real – they exist and are distinct from the particulars that instantiate them. there are various forms of realism. two major forms are platonic realism and aristotelian realism. platonic realism is the view that universals are real entities and they exist independent of particulars. aristotelian realism, on the other hand, is the view that universals are real entities, but their existence is dependent on the particulars that exemplify them. time and space a traditional realist position in ontology is that time and space have existence apart from the human mind. idealists deny or doubt the existence of objects independent of the mind. some anti - realists whose ontological position is that objects outside the mind do exist, nevertheless doubt the independent existence of time and space. kant, in the critique of pure reason, described time as an a priori notion that, together with other a priori notions such as space, allows us to comprehend sense experience. kant denies that either space or time are substance, entities in themselves, or learned by experience ; he holds rather that both are elements of a systematic framework we use to structure our experience. spatial measurements are used to quantify how far apart objects are, and temporal measurements are used to quantitatively compare the interval between ( or duration of ) events. although space and time are held to be transcedentally ideal in this sense, they are also empirically real, i. e. not mere illusions. - presentism holds that the past and future are unreal, and only an ever changing present is real. - the block universe theory, also known as eternalism, holds that past, present and future are all real, but the passage of time is an illusion. it is often said to have a scientific basis in relativity. - the growing block universe theory holds that past and present are real, but the future is not. the term " possible world " goes back to leibniz ' s theory of possible worlds, used to analyse necessity, possibility, and similar modal notions. modal realism is the view, notably propounded by david kellogg lewis, that all possible worlds are as real as the actual world. in short : the actual world is regarded as merely one among an infinite set of logically possible worlds, some " nearer " to the actual world and some more remote.


david kellogg lewis, that all possible worlds are as real as the actual world. in short : the actual world is regarded as merely one among an infinite set of logically possible worlds, some " nearer " to the actual world and some more remote. other theorists may use the possible world framework to express and explore problems without committing to it ontologically. possible world theory is related to alethic logic : a proposition is necessary if it is true in all possible worlds, and possible if it is true in at least one. the many worlds interpretation of quantum mechanics is a similar idea in science. theories of everything ( toe ) and philosophy the philosophical implications of a physical toe are frequently debated. for example, if philosophical physicalism is true, a physical toe will coincide with a philosophical theory of everything. the " system building " style of metaphysics attempts to answer all the important questions in a coherent way, providing a complete picture of the world. plato and aristotle could be said to be early examples of comprehensive systems. in the early modern period ( 17th and 18th centuries ), the system - building scope of philosophy is often linked to the ratioanlist method of philosophy, that is the technique of deducing the nature of the world by pure a priori reason. examples from the early modern period include the leibniz ' s monadology, descarte ' s dualism, spinoza ' s monism. hegel ' s absolute idealism and whitehead ' s process philosophy were later systems. other philosophers do not believe its techniques can aim so high. some scientists think a more mathematical approach than philosophy is needed for a toe, for instance stephen hawking wrote in a brief history of time that even if we had a toe, it would necessarily be a set of equations. he wrote, " what is it that breathes fire into the equations and makes a universe for them to describe? ". on a much broader and more subjective level, private experiences, curiosity, inquiry, and the selectivity involved in personal interpretation of events shapes reality as seen by one and only one individual and hence is called phenomenological. while this form of reality might be common to others as well, it could at times also be so unique to oneself as to never be experienced or agreed upon by anyone else. much of the kind of experience deemed spiritual occurs on this level of reality. phenomenology is a philosophical method developed in the early years of the twentieth century by edmund husserl and a circle of followers at the universities of gottingen and


else. much of the kind of experience deemed spiritual occurs on this level of reality. phenomenology is a philosophical method developed in the early years of the twentieth century by edmund husserl and a circle of followers at the universities of gottingen and munich in germany. subsequently, phenomenological themes were taken up by philosophers in france, the united states, and elsewhere, often in contexts far removed from husserl ' s work. the word phenomenology comes from the greek phainomenon, meaning " that which appears ", and logos, meaning " study ". in husserl ' s conception, phenomenology is primarily concerned with making the structures of consciousness, and the phenomena which appear in acts of consciousness, objects of systematic reflection and analysis. such reflection was to take place from a highly modified " first person " viewpoint, studying phenomena not as they appear to " my " consciousness, but to any consciousness whatsoever. husserl believed that phenomenology could thus provide a firm basis for all human knowledge, including scientific knowledge, and could establish philosophy as a " rigorous science ". husserl ' s conception of phenomenology has been criticised and developed not only by himself, but also by his student and assistant martin heidegger, by existentialists, such as maurice merleau - ponty, jean - paul sartre, and by other philosophers, such as paul ricoeur, emmanuel levinas, and dietrich von hildebrand. skeptical hypotheses in philosophy suggest that reality is very different from what we think it is ; or at least that we cannot prove it is not. examples include : - the " brain in a vat " hypothesis is cast in scientific terms. it supposes that one might be a disembodied brain kept alive in a vat, and fed false sensory signals, by a mad scientist. - the " dream argument " of descartes and zhuangzi supposes reality to be indistinguishable from a dream. - descarte ' s evil demon is a being " as clever and deceitful as he is powerful, who has directed his entire effort to misleading me. " - the five minute hypothesis ( or omphalos hypothesis or last thursdayism ) suggests that the world was created recently together with records and traces indicating a greater age. - the matrix hypothesis or simulated reality hypothesis suggest that we might be inside a computer simulation or virtual reality. scientific realism is, at the most general level,


classical mechanics, of general relativity, and of electrodynamics ; but quantum mechanics has shown that quantum entanglement is possible. this was rejected by einstein, who proposed the epr paradox, but it was subsequently quantified by bell ' s inequalities. if bell ' s inequalities are violated, either local realism or counterfactual definiteness must be incorrect ; but some physicists dispute that experiments have demonstrated bell ' s violations, on the grounds that the sub - class of inhomogeneous bell inequalities has not been tested or due to experimental limitations in the tests. different interpretations of quantum mechanics violate different parts of local realism and / or counterfactual definiteness. role of the observer in quantum mechanics the quantum mind – body problem refers to the philosophical discussions of the mind – body problem in the context of quantum mechanics. since quantum mechanics involves quantum superpositions, which are not perceived by observers, some interpretations of quantum mechanics place conscious observers in a special position. the founders of quantum mechanics debated the role of the observer, and of them, wolfgang pauli and werner heisenberg believed that it was the observer that produced collapse. this point of view, which was never fully endorsed by niels bohr, was denounced as mystical and anti - scientific by albert einstein. pauli accepted the term, and described quantum mechanics as lucid mysticism. heisenberg and bohr always described quantum mechanics in logical positivist terms. bohr also took an active interest in the philosophical implications of quantum theories such as his complementarity, for example. he believed quantum theory offers a complete description of nature, albeit one that is simply ill suited for everyday experiences – which are better described by classical mechanics and probability. bohr never specified a demarcation line above which objects cease to be quantum and become classical. he believed that it was not a question of physics, but one of philosophy. eugene wigner reformulated the " schrodinger ' s cat " thought experiment as " wigner ' s friend " and proposed that the consciousness of an observer is the demarcation line which precipitates collapse of the wave function, independent of any realist interpretation. commonly known as " consciousness causes collapse ", this interpretation of quantum mechanics states that observation by a conscious observer is what makes the wave function collapse. the multiverse is the hypothetical set of multiple possible universes ( including the historical universe we consistently experience ) that together comprise everything that exists : the entirety of space


of quantum mechanics states that observation by a conscious observer is what makes the wave function collapse. the multiverse is the hypothetical set of multiple possible universes ( including the historical universe we consistently experience ) that together comprise everything that exists : the entirety of space, time, matter, and energy as well as the physical laws and constants that describe them. the term was coined in 1895 by the american philosopher and psychologist william james. in the many - worlds interpretation ( mwi ), one of the mainstream interpretations of quantum mechanics, there are an infinite number of universes and every possible quantum outcome occurs in at least one universe. the structure of the multiverse, the nature of each universe within it and the relationship between the various constituent universes, depend on the specific multiverse hypothesis considered. multiverses have been hypothesized in cosmology, physics, astronomy, religion, philosophy, transpersonal psychology and fiction, particularly in science fiction and fantasy. in these contexts, parallel universes are also called " alternative universes ", " quantum universes ", " interpenetrating dimensions ", " parallel dimensions ", " parallel worlds ", " alternative realities ", " alternative timelines ", and " dimensional planes, " among others. scientific theories of everything a theory of everything ( toe ) is a putative theory of theoretical physics that fully explains and links together all known physical phenomena, and predicts the outcome of any experiment that could be carried out in principle. the theory of everything is also called the final theory. many candidate theories of everything have been proposed by theoretical physicists during the twentieth century, but none have been confirmed experimentally. the primary problem in producing a toe is that general relativity and quantum mechanics are hard to unify. this is one of the unsolved problems in physics. initially, the term " theory of everything " was used with an ironic connotation to refer to various overgeneralized theories. for example, a great - grandfather of ijon tichy, a character from a cycle of stanisław lem ' s science fiction stories of the 1960s, was known to work on the " general theory of everything ". physicist john ellis claims to have introduced the term into the technical literature in an article in nature in 1986. over time, the term stuck in popularizations of quantum physics to describe a theory that would unify or explain through a single model the theories of all fundamental interactions and of all particles of nature : general relativity for gravitation, and the standard model of elementary


, the term stuck in popularizations of quantum physics to describe a theory that would unify or explain through a single model the theories of all fundamental interactions and of all particles of nature : general relativity for gravitation, and the standard model of elementary particle physics – which includes quantum mechanics – for electromagnetism, the two nuclear interactions, and the known elementary particles. virtual reality and cyberspace the virtuality continuum is a continuous scale ranging between the completely virtual, a virtuality, and the completely real : reality. the reality - virtuality continuum therefore encompasses all possible variations and compositions of real and virtual objects. it has been described as a concept in new media and computer science, but in fact it could be considered a matter of anthropology. the concept was first introduced by paul milgram. the area between the two extremes, where both the real and the virtual are mixed, is the so - called mixed reality. this in turn is said to consist of both augmented reality, where the virtual augments the real, and augmented virtuality, where the real augments the virtual. cyberspace, the world ' s computer systems considered as an interconnected whole, can be thought of as a virtual reality ; for instance, it is portrayed as such in the cyberpunk fiction of william gibson and others. second life and mmorpgs such as world of warcraft are examples of artificial environments or virtual worlds ( falling some way short of full virtual reality ) in cyberspace. " rl " in internet culture on the internet, " real life " refers to life in the real world. it generally references life or consensus reality, in contrast to an environment seen as fiction or fantasy, such as virtual reality, lifelike experience, dreams, novels, or movies. online, the acronym " irl " stands for " in real life ", with the meaning " not on the internet ". sociologists engaged in the study of the internet have determined that someday, a distinction between online and real - life worlds may seem " quaint ", noting that certain types of online activity, such as sexual intrigues, have already made a full transition to complete legitimacy and " reality ". the abbreviation " rl " stands for " real life ". for example, one can speak of " meeting in rl " someone whom one has met in a chat or on an internet forum. it may also be used to express an inability to use the internet for a time due to " rl problems ". - compact oxford english dictionary of current english


in rl " someone whom one has met in a chat or on an internet forum. it may also be used to express an inability to use the internet for a time due to " rl problems ". - compact oxford english dictionary of current english, oxford university press, 2005. ( full entry for reality : " reality • noun ( pl. realities ) 1 the state of things as they actually exist, as opposed to an idealistic or notional idea of them. 2 a thing that is actually experienced or seen. 3 the quality of being lifelike. 4 the state or quality of having existence or substance. " ) - lehar, steve. ( 2000 ). the function of conscious experience : an analogical paradigm of perception and behavior, consciousness and cognition. - lehar, steve. ( 2000 ). naive realism in contemporary philosophy, the function of conscious experience. - lehar, steve. representationalism - tegmark, max ( february 2008 ). " the mathematical universe ". foundations of physics 38 ( 2 ) : 101 – 150. arxiv : 0704. 0646. bibcode : 2008foph... 38.. 101t. doi : 10. 1007 / s10701 - 007 - 9186 - 9. - tegmark ( 1998 ), p. 1. - loux ( 2001 ), p. 4 - price ( 1953 ), among others, sometimes uses such latin terms - as quoted in [ artigas, the mind of the universe, p. 123 ] - joseph kockelmans ( 2001 ). edmund husserl ' s phenomenology ( 2 ed. ). purdue university press. pp. 311 – 314. isbn 1 - 55753 - 050 - 5 [ amazon - us | amazon - uk ]. - steven galt crowell ( 2001 ). husserl, heidegger, and the space of meaning : paths toward transcendental phenomenology. northwestern university press. p. 160. isbn 0 - 8101 - 1805 - x [ amazon - us | amazon - uk ]. - norsen, t. – against " realism " - ian thomson ' s dispositional quantum mechanics - ben dov, y. local realism and the crucial experiment. - juan miguel marin ( 2009 ). " ' mysticism ' in quantum mechanics : the forgotten controversy ". european journal of physics 30 : 807 – 822. bibcode : 2009ejph...


realism and the crucial experiment. - juan miguel marin ( 2009 ). " ' mysticism ' in quantum mechanics : the forgotten controversy ". european journal of physics 30 : 807 – 822. bibcode : 2009ejph... 30.. 807m. doi : 10. 1088 / 0143 - 0807 / 30 / 4 / 014. link, summarized here - john honner ( 2005 ). " niels bohr and the mysticism of nature ". zygon journal of science and religion 17 – 3 : 243 – 253. - james, william, the will to believe, 1895 ; and earlier in 1895, as cited in oed ' s new 2003 entry for " multiverse " : " 1895 w. james in internat. jrnl. ethics 6 10 visible nature is all plasticity and indifference, a multiverse, as one might call it, and not a universe. " - weinberg ( 1993 ) - ellis, john ( 2002 ). " physics gets physical ( correspondence ) ". nature 415 ( 6875 ) : 957. bibcode : 2002natur. 415.. 957e. doi : 10. 1038 / 415957b. - ellis, john ( 1986 ). " the superstring : theory of everything, or of nothing? ". nature 323 ( 6089 ) : 595 – 598. bibcode : 1986natur. 323.. 595e. doi : 10. 1038 / 323595a0. - milgram, paul ; h. takemura, a. utsumi, f. kishino ( 1994 ). " augmented reality : a class of displays on the reality - virtuality continuum " ( pdf ). proceedings of telemanipulator and telepresence technologies. pp. 2351 – 34. http : / / vered. rose. utoronto. ca / publication / 1994 / milgram _ takemura _ spie1994. pdf. retrieved 2007 - 03 - 15. - " acronymfinder. com search for irl ". - don slater ( 2002 ). " social relationships and identity on - line and off - line ". in leah, sonia, lievrouw, and livingstone. handbook of new media : social shaping and consequences of icts. sage publications inc. pp. 533 – 543. isbn 0 - 7619 - 6510 - 6 [ amazon - us | amazon -


thorfinn. au sends along big physics news : magnetic monopoles have been detected at low temperatures in " dirac strings " within a single crystal of dysprosium titanate. two papers are being published today in the journal science and two more on arxiv. org, as yet unpublished, provide further evidence. " theoretical work had shown that monopoles probably exist, and they have been measured indirectly. but the science papers are the first direct experiments to record the monopole ' s effects on the spin - ice material. the papers use neutrons to detect atoms in the crystal aligned into long daisy chains. these daisy chains tie each north and south monopole together. known as ' dirac strings, ' the chains, as well as the existence of monopoles, were predicted in the 1930s by the british theoretical physicist paul dirac. heat measurements in one paper also support the monopole argument. the two, as yet unpublished, papers on arxiv add to the evidence. the first provides additional observations, and the second uses a new technique to determine the magnetic charge of each monopole to be 4. 6x10 - 13 joules per tesla metre. all together, the evidence for magnetic monopoles ' is now overwhelming, ' says steve bramwell, a materials scientist at university college london and author on one of the science papers and one of the arxiv papers. "


definition of warmth : 1. a state of lively and excited interest ; zeal ; ardor ; fervor ; passion ; enthusiasm ; earnestness ; as, the warmth of love or piety ; he replied with much warmth. 2. the glowing effect which arises from the use of warm colors ; hence, any similar appearance or effect in a painting, or work of color. 3. the quality or state of being warm ; gentle heat ; as, the warmth of the sun ; the warmth of the blood ; vital warmth. partiality, high temperature, congenialness, solicitude, cordialness, liberality, support, warmness, earnestness, genialness, caring, frenzy, congeniality, eighties, heating system, heating, eagerness, lovingness, zeal, excitement, passionateness, rage, mania, heating plant, white heat, agreeableness, passion, fanaticism, feelings, hot, geniality, agreeability, rut, tepidity, heart, centigrade, fancy, fahrenheit, absolute zero, violence, ecstasy, excite, warmheartedness, pleasantness, tepidness, fervency, inspiration, fervidness, affectionateness, generosity, consideration, amiability, philia, cordiality, excitation, charity, heat energy, fervor, f., intensity, amenity, good, attitude, ardency, celsius, rapture, c, vehemence, altruism, oestrus, affability, amiableness, sociability, boiling point, sociableness, ardor, degree, lukewarmness, bimetallic strip, emotion, extravagance, hospitality, intenseness, hotness, estrus, enthusiasm, cacoethes, transport affection ( part of speech : noun ) heat ( part of speech : verb ) - and what warmth and light there was to look upon! - " a man and a woman ", stanley waterloo. - but in winter, at least, when you need warmth, you must have to fall back on our old friend the sheep. - " equality ", edward bellamy. - the night was more chilly than the preceding one, and the warmth of the blankets would have been pleasant to both. - " the lost trail ", edward s. ellis.


electronics basics : resistance in the electronics world, resistance is not futile. in fact, resistance can be very useful. without resistance, electronics would not be possible. electronics is all about manipulating the flow of current, and one of the most basic ways to manipulate current is to reduce it through resistance. without resistance, current would flow unregulated and there would be no way to coax it into doing useful work. a conductor is a material that allows current to flow, and an insulator is a material that doesn ' t. good conductors allow current to flow with abandon, without impediments. examples of good conductors include the metals copper and aluminum. carbon is also an excellent conductor. good insulators, on the other hand, erect solid walls that completely block current. examples of good insulators include glass, teflon, and plastic. the key factor that determines whether a material is a conductor or an insulator is how readily its atoms give up electrons to move charge along. most atoms are very possessive of their electrons, and are therefore good insulators. but some atoms don ' t have a strong hold on their outermost electrons. those atoms are good conductors. if a conductor and an insulator are mixed together, the result is a compound that conducts current, but not very well. such a compound has resistance — that is, it resists the flow of current. the degree to which the compound resists current depends on the exact mix of elements that make up the compound. for example, a conducting material such as carbon might be mixed with an insulating material such as ceramic. if the mix is mostly carbon, the overall resistance of the mixture will be low. if the mix is mostly ceramic, the overall resistance will be high. the truth is that all materials have some resistance. even the best conductors have a small but measurable amount of resistance. the only exceptions are certain materials called superconductors that, when chilled to unbelievably low temperatures, conduct with 100 percent efficiency.


. the present invention relates, in general, to microelectromechanical structures ( mems ), such as torsional cantilevers, to actuators for mems devices, and to methods for fabricating such structures. more particularly, the invention relates to high aspect ratio, single crystal silicon mems devices, such as a torsional cantilever having a cantilever moment arm mounted on a torsional support beam, to actuators incorporating multiple interleaved comb drive fingers which are energizable to actuate the cantilever, to a novel actuator structure, and to a process for fabricating such structures which is compatible with processes for making conventional silicon integrated circuits. since their development in the early 1980s, scanning probe microscopes have become important tools for surface analysis and surface modification. the unique applications of scanning probe microscopes include imaging and manipulating single atoms, measuring forces on the atomic scale, and performing nm - scale lithography. at the center of the family of scanning probe microscopes are the scanning tunnelling microscope ( stm ) and the atomic force microscope ( afm ). these macroscopic scanned probe instruments, for the most part, use large piezoelectric actuators to position a sensing tip or a probe in three dimensions ( xyz ) and thus to provide relative motion between the tip and a sample surface. however, the size of these microscopic instruments limits their performance, for the mass of the tip - actuator structure produces low resonant frequencies and low scanning rates. more importantly, these large instruments cannot be easily integrated into arrays for high speed scanning and atom manipulation, for information storage, or for high throughput, nm - scale lithography systems. a cantilever of some sort is often used in macroscopic force microscopy to monitor the variations in forces which represent the interaction between a tip and a sample. in such cases, the cantilever is usually a silicon nitride " v " cantilever which, for example, may be 0. 6 to 2 micrometers thick, may be 100 to 200 micrometers long, and which may have a spring constant of between about 0. 03 and 3 n / m for contact mode imaging. see, for example, t. r. albrecht et al., j. vac. sci. technol. a8, 3386 ( 1990 ). for non - contact mode imaging, the cantilever may be silicon with a spring constant of


for example, t. r. albrecht et al., j. vac. sci. technol. a8, 3386 ( 1990 ). for non - contact mode imaging, the cantilever may be silicon with a spring constant of about 1 to 100 n / m, as described by wolter et al., j. vac. sci. technol. b9, 1353 ( 1991 ). in order to obtain a high degree of sensitivity, a low spring constant k and a high q is needed for such cantilevers, and attempts have been made to accomplish this through the use of thin films. however, it is necessary to make the cantilever very thin in order to achieve a low spring constant with a thin film ; for example, magnetic resonance force detection has been performed using a cantilever ( without an integrated tip ) that was only 900 a thick, and which had a spring constant of 10. sup. - 3 n / m. however, the fabrication and use of such thin cantilevers poses many problems, including the problem of tip integration, problems with internal stress, and problems in making electrical connections and in amplifying the resulting signals. for many years, torsion has been used as a technique for highly sensitive measurements of force interactions ; for example, measurement of coulomb ' s torsional balance for electrostatic forces and cavendish ' s balance for gravitation. furthermore, torsional resonators have been used as high - q resonators to study a variety of physical properties, such as dissipation and visoelasticity. such devices have been widely used because cantilevers, resonators, or balances can be made symmetric with respect to their center of mass, with the result that lateral vibrations of the support do not couple to the torsional mode of the sensor device. in the case where the measuring device includes a spring, lateral modes of the spring can be made much stiffer than the torsional mode without affecting the torsional behavior, thus making torsional measurements desirable. torsional cantilevers are known to provide a viable option in scanning force microscopy. however, such cantilevers have, in the past, been assembled by hand, using cleaved pieces of silicon, carbon fibers or tungsten wire, and epoxy. such devices did not incorporate integrated tips and, although microfabricated cantilevers have been demonstrated, such devices exhibited a lateral stiffness which was as


cleaved pieces of silicon, carbon fibers or tungsten wire, and epoxy. such devices did not incorporate integrated tips and, although microfabricated cantilevers have been demonstrated, such devices exhibited a lateral stiffness which was as soft as, or softer than that of a v - shaped cantilever. the lack of sufficient lateral stiffness can result in unwanted " stick - slip " behavior as the cantilever is scanned across samples. the present invention is directed to microelectromechanical structures ( mems ) which incorporate capacitive actuators, or drivers, for producing mechanical motion, and more particularly to an improved comb - type actuator structure which can be used with a wide range of mems devices to provide improved control of the motion of such devices. the comb - type structure consists of high aspect ratio mems beams fabricated as interleaved fixed and movable capacitor fingers. the beams may be electrically conductive or may carry a conductive layer so that application of a voltage between adjacent fingers produces an electrostatic force which tends to produce relative motion of the fingers. furthermore, application of an external mechanical force which causes relative motion of the fingers produces a corresponding change in the field between the fixed and movable fingers and this change can be measured by suitable electrical circuitry connected to the fingers. in accordance with the invention, the fixed and movable mems actuator fingers used to form comb - type capacitive actuator structures are of different heights, and such asymmetry has been found to produce numerous advantages over prior comb - type actuators. for example, it has been found that an asymmetric finger height increases the force produced in a vertical, out - of - plane direction between adjacent fingers, providing improved vertical actuation and motion control in mems devices to which the fingers are attached. the asymmetric configuration also provides control of the total amount of out - of - plane static deformation that occurs in mems structures, and allows actuators so constructed to produce vertical motion even in the absence of a substrate ground plane. in a preferred form of the invention, the actuator is fabricated on a substrate as a part of a mems structure whose motion is to be controlled, or measured. the movable actuator fingers form electrodes, and these fingers and the substrate are electrically grounded. a potential, which may be variable, is applied to the fixed finger electrodes. the fixed fingers have a greater height than the mo


measured. the movable actuator fingers form electrodes, and these fingers and the substrate are electrically grounded. a potential, which may be variable, is applied to the fixed finger electrodes. the fixed fingers have a greater height than the movable fingers, causing the electric field produced by the applied potential, between the electrodes to be vertically asymmetric. this asymmetric field creates a vertical force which causes the movable finger electrodes to shift vertically with respect to the fixed finger electrodes. the vertical force can be used to generate static displacements of mems devices, to produce vibrational motion, or to otherwise control the motion of the device or structure to which the actuator is connected. conversely, motion of the device or structure produced by external forces produces relative motion of the actuator fingers which changes the electrostatic field, and such changes are a measure of the applied external force. the present actuator may be used, in one aspect of the invention, to drive, and to measure the motion of, mems structures, such as a torsional cantilever which is microfabricated for reduced size to increase its resonant frequency and thereby to increase its scanning speed. such a microfabricated cantilever may incorporate an integrated tip so that it is particularly adapted to provide highly sensitive detection of forces, and both the cantilever and the drive actuators preferably are integral with a substrate which may incorporate conventional integrated circuits to which the actuator as well as the cantilever and / or its tip may be electrically connected. in a preferred form of this invention, mems devices are fabricated from a substrate material of single crystal silicon, with the cantilever and integral actuator structures preferably being fabricated by the single crystal reactive etch and metallization ( scream - i ) process described in copending u. s. patent application ser. no. 08 / 312, 797 filed sep. 27, 1994 of kevin a. shaw, z. lisa zhang, and noel c. macdonald, now u. s. pat. no. 5, 719, 073, issued feb. 17, 1998, the disclosure of which is hereby incorporated herein by reference. this fabrication process allows integration of an actuator structure and any desired movable structure on a single crystal silicon substrate which may carry pre - existing integrated circuits. the movable structure may be a cantilever with an integral submicron tip for use, for example,


, with the sample being scannable in the y direction. in another configuration, the z cantilevers can be fabricated as part of a micromechanical stage that is scannable in x and y directions, with the sample remaining stationary. the sample can be a chip with a bare surface or a compliant surface, or can be an active mem device. alternatively, the sample can be placed on or bonded to a chip which carries an array of microscanned probe devices, wherein the torsional cantilever elements which make up the probe provide enough out - of - plane ( or z - direction ) motion to allow the tips to contact the surface. to facilitate this, sample support pillars or posts are fabricated on the chip which carries the array, with the pillars having the same height as, or being a little taller than, the tips. a large number of electrical connections are required in an array of cantilevers to carry control signals for individually moving the cantilever arms or for carrying sensor output signals from each arm. transistors for switching among various devices can reduce the number of connections, and such switches can be in the form of normal planar ic transistors fabricated on the silicon substrate. metal pathways along the substrate provide the necessary connections. suspended transistors in the silicon beams can also be used for switching, amplification, and logic, and electrical isolation can be provided by oxide segments in the beams. the cantilevered arms and arrays of such arms can be used in a wide range of applications. in addition to scanning of images and the manipulation of surfaces at atomic and near - atomic scales, the devices and arrays of the invention can be used for high density information storage, in the range of a terabit per cm. sup. 2, for molecular manipulation instruments, for field emission ( e - beam ) instruments, and for microlithographic or micromachining tools. the foregoing, and additional objects, features and advantages of the present invention will become apparent to those of skill in the art from the following detailed description of preferred embodiments thereof, taken in conjunction with the accompanying drawings, in which : fig. 1 is a partial perspective view in diagrammatic form of a torsional cantilever device in accordance with the present invention ; fig. 2 is a top plan view of the cantilever device of fig. 1 ; figs. 3 ( a ) through 3 ( h ) illustrate a process for fabricating sensor tips on the device of fig.


with the present invention ; fig. 2 is a top plan view of the cantilever device of fig. 1 ; figs. 3 ( a ) through 3 ( h ) illustrate a process for fabricating sensor tips on the device of fig. 1 ; figs. 4 ( a ) and 4 ( b ) are diagrammatic illustrations of a metallization process - used in the device of fig. 1 ; fig. 5 is a partial, enlarged view of the cantilever structure of figs. 1 and 2 ; fig. 6 is an enlarged, partial view of the torsional support beam for the device of fig. 1 ; fig. 7 is a graphical illustration of curves representing the relationship of effective spring constant to cantilever length for different cantilever cross - sectional widths " a " each having a cantilever cross - sectional height " b " of 10 μm ; fig. 8 is a top plan view of a second embodiment of the cantilever device of the present invention ; fig. 9 is a top plan view of a third embodiment of the cantilever device of the present invention, utilizing torsion control electrodes ; fig. 10 is a cross - sectional view taken along lines 10 - - 10 of fig. 9 ; fig. 11 is a fourth embodiment of the cantilever device of the present invention, utilizing comb - type capacitive sensors for motion sensing and compensation ; fig. 12 is a fifth embodiment of the device of the present invention, utilizing comb - type capacitive actuators or sensors ; fig. 13 is a partial, enlarged perspective view of a modified comb - type actuator or sensor for the device of fig. 12 ; fig. 14 illustrates a first alternative version of the comb - type actuator or sensor of fig. 13 ; fig. 15 illustrates a second alternative version of the comb - type actuator or sensor of fig. 13 ; fig. 16 is a sixth embodiment of the cantilever device of the present invention, combining the features of figs. 13 and 14 ; fig. 17 is a diagrammatic illustration of the use of the torsional cantilever device of the present invention in an atomic force microscope ; fig. 18 is a photomicrograph of the torsional cantilever device of the present invention incorporated in an capacitor - driven xy stage configuration ; fig. 19 is a diagrammatic illustration of an array of cantilevered sensors mounted


fingers of different heights. turning now to a more detailed consideration of the present invention, there is illustrated in fig. 1 a perspective view of a microfabricated, highly sensitive force detecting torsional cantilever device 10 incorporating an elongated torsionally - mounted microelectromechanical ( mem ) cantilever moment arm generally indicated at 12. this device has a wide range of applications, but will be described herein for convenience as being used as a force sensor in scanning probe microscopy. the cantilever moment arm portion 12 is mounted at a first, or near end 14 to the center of a laterally extending torsional support beam 16. in the illustrated embodiment, the opposite ends of the beam 16 are supported on, and preferably are integral with, a substrate 18 as at support mesas 19 and 20. the moment arm 12 is integral with beam 16 and in its preferred form is a grid of longitudinal and lateral beams, as illustrated in fig. 1, the arm extending from a near end 14 generally horizontally forwardly from the support beam 16 to a far, or distal, end 21 along a longitudinal axis 22 ( fig. 2 ) which is perpendicular to beam 16. an upwardly - extending, or generally vertical, nanometer - scale sensing tip 23 is formed on the distal end 21 of the cantilever moment arm in the preferred form of the invention. this sensing tip is generally conical, tapering upwardly and inwardly to an extremely small diameter, on the order of one atom, at its end 24. the moment arm 12 and support beam 16 lie in an x - y plane, with tip 23 extending perpendicularly to the plane, in a z direction. also mounted on lateral support beam 16, but on the opposite side thereof from moment arm 12, is a counterweight 26 which is also fabricated as a grid of longitudinal and lateral beams ( not shown in fig. 1 ), and which is of sufficient size and weight to produce a counterbalancing mass for the cantilevered moment arm so as to make the arm 12 more sensitive to, and responsive to, forces applied to tip 23. the counterweight 26 serves as an extension of cantilever moment arm 12 so that arm 12 and counterweight 26 rotate together about a lateral axis 27 ( see fig. 2 ) of the beam 16. axis 27 lies in the x - y plane of arm 12 and beam 16, with axis 27 being perpendicular to the longitudinal axis 22 of arm 12. rotation of arm 12