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a biocompatible material and is completely resorbed following implantation. It does not evoke a significant host response and creates a calcium-rich milieu in the area of implantation. === Desiccant === When sold at the anhydrous state as a desiccant with a color-indicating agent under the name Drierite, it appears blu...	{ "page_id": 595183, "title": "Calcium sulfate" }
In the production of phosphoric acid from phosphate rock, calcium phosphate is treated with sulfuric acid and calcium sulfate precipitates. The product, called phosphogypsum is often contaminated with impurities making its use uneconomic. In the production of hydrogen fluoride, calcium fluoride is treated with sulfuric...	{ "page_id": 595183, "title": "Calcium sulfate" }
(mineral) Flue-gas desulfurization == References == == External links == International Chemical Safety Card 1215 NIOSH Pocket Guide to Chemical Hazards	{ "page_id": 595183, "title": "Calcium sulfate" }
A Naturalist in Indian Seas, or, Four Years with the Royal Indian Marine Survey Ship Investigator is a 1902 publication by Alfred William Alcock, a British naturalist and carcinologist. The book is mostly a narrative describing the Investigator's journey through areas of the Indian Ocean, such as the Laccadive Sea, the...	{ "page_id": 1512690, "title": "A Naturalist in Indian Seas" }
Alsuviricetes is a class of positive-strand RNA viruses which infect eukaryotes. The name of the group is a syllabic abbreviation of "alpha supergroup" with the suffix -viricetes indicating a virus class. == Taxonomy == The following orders are recognized: Hepelivirales Martellivirales Tymovirales == References ==	{ "page_id": 63771890, "title": "Alsuviricetes" }
Beta-decay stable isobars are the set of nuclides which cannot undergo beta decay, that is, the transformation of a neutron to a proton or a proton to a neutron within the nucleus. A subset of these nuclides are also stable with regards to double beta decay or theoretically higher simultaneous beta decay, as they have ...	{ "page_id": 23270645, "title": "Beta-decay stable isobars" }
123Te and 180mTa have not been observed to decay, but are believed to undergo beta decay with extremely long half-lives (over 1015 years). Theoretically, 123Te can only undergo electron capture to 123Sb, whereas 180mTa can decay in both directions, to 180Hf or 180W. Among non-primordial nuclides, there are some other c...	{ "page_id": 23270645, "title": "Beta-decay stable isobars" }
and 99Ru), and 85 (145Nd and 147Sm); the first four cases involve very light nuclides where odd-odd nuclides are more stable than their surrounding even-even isobars, and the last two surround the proton numbers 43 and 61 which have no beta-stable isotopes. Also, two beta-decay stable nuclides exist for odd proton numb...	{ "page_id": 23270645, "title": "Beta-decay stable isobars" }
also primordial but not beta-stable 87Rb), 58 (100Mo, 102Ru, 103Rh, 104Pd, and 106Cd), 74 (124Sn, 126Te, 127I, 128Xe, and 130Ba), 78 (130Te, 132Xe, 133Cs, 134Ba, and 136Ce), 88 (148Nd, 150Sm, 151Eu, 152Gd, and 154Dy – the last not primordial), and 90 (150Nd, 152Sm, 153Eu, 154Gd, and 156Dy). For A ≤ 209, the only beta-d...	{ "page_id": 23270645, "title": "Beta-decay stable isobars" }
primarily through alpha decay or spontaneous fission. Beyond the island of stability, various models that correctly predict many known beta-stable isotopes also predict anomalies in the beta-stability line that are unobserved in any known nuclides, such as the existence of two beta-stable nuclides with the same odd mas...	{ "page_id": 23270645, "title": "Beta-decay stable isobars" }
or electron capture. However, there are a few odd-odd nuclides between two beta-stable even-even isobars, that predominantly decay to the higher-mass of the two beta-stable isobars. For example, 40K could either undergo electron capture or positron emission to 40Ar, or undergo beta minus decay to 40Ca: both possible pr...	{ "page_id": 23270645, "title": "Beta-decay stable isobars" }
A text-to-image model is a machine learning model which takes an input natural language description and produces an image matching that description. Text-to-image models began to be developed in the mid-2010s during the beginnings of the AI boom, as a result of advances in deep neural networks. In 2022, the output of s...	{ "page_id": 71701751, "title": "Text-to-image model" }
Reed, Akata, Yan et al. became the first to use generative adversarial networks for the text-to-image task. With models trained on narrow, domain-specific datasets, they were able to generate "visually plausible" images of birds and flowers from text captions like "an all black bird with a distinct thick, rounded bill"...	{ "page_id": 71701751, "title": "Text-to-image model" }
technique is to train a model to generate low-resolution images, and use one or more auxiliary deep learning models to upscale it, filling in finer details. Text-to-image models are trained on large datasets of (text, image) pairs, often scraped from the web. With their 2022 Imagen model, Google Brain reported positive...	{ "page_id": 71701751, "title": "Text-to-image model" }
to text-to-image models is that generated images semantically align with the text captions used to generate them. A number of schemes have been devised for assessing these qualities, some automated and others based on human judgement. A common algorithmic metric for assessing image quality and diversity is the Inceptio...	{ "page_id": 71701751, "title": "Text-to-image model" }
A sodium bicarbonate rocket (sometimes called an Alka-Seltzer rocket) is a model rocket fashioned from a 35mm film canister and propelled by the pressure of a gas, often carbon dioxide, generated from the reaction of an acid with sodium bicarbonate. Sodium bicarbonate rockets are often used in science classes to demons...	{ "page_id": 14095613, "title": "Sodium bicarbonate rocket" }
liquid fuel to create a gas that escapes out of the bottom. The gas is carbon dioxide (CO2), the liquid is water (H2O), and the solid is an effervescent tablet. When the H2O is mixed with an effervescent tablet, it produces the gas CO2. The reaction time depends on the surface area of the tablet. == See also == Water r...	{ "page_id": 14095613, "title": "Sodium bicarbonate rocket" }
Hepelivirales is an order of viruses. == Taxonomy == The order contains the following families: Alphatetraviridae Benyviridae Hepeviridae Matonaviridae Mycoalphaviridae == References ==	{ "page_id": 63771902, "title": "Hepelivirales" }
Cladistics ( klə-DIST-iks; from Ancient Greek κλάδος kládos 'branch') is an approach to biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived characteristics (synapomor...	{ "page_id": 5376, "title": "Cladistics" }
and a new level on that branch. Specifically, also extinct groups are always put on a side-branch, not distinguishing whether an actual ancestor of other groupings was found. The techniques and nomenclature of cladistics have been applied to disciplines other than biology. (See phylogenetic nomenclature.) Cladistics fi...	{ "page_id": 5376, "title": "Cladistics" }
conceived, if only in essence, by Willi Hennig in a book published in 1950, cladistics did not flourish until its translation into English in 1966 (Lewin 1997). Today, cladistics is the most popular method for inferring phylogenetic trees from morphological data. In the 1990s, the development of effective polymerase ch...	{ "page_id": 5376, "title": "Cladistics" }
one large clade; phylogenetic analysis infers the branching pattern within that clade. Different datasets and different methods, not to mention violations of the mentioned assumptions, often result in different cladograms. Only scientific investigation can show which is more likely to be correct. Until recently, for ex...	{ "page_id": 5376, "title": "Cladistics" }
perspective of a tarsier, humans and lemurs would have looked close, in the exact same sense. Cladistics forces a neutral perspective, treating all branches (extant or extinct) in the same manner. It also forces one to try to make statements, and honestly take into account findings, about the exact historic relationshi...	{ "page_id": 5376, "title": "Cladistics" }
tetrapods can be singled out as consisting of the first vertebrate with such digits homologous to those of Homo sapiens together with all descendants of this vertebrate (an apomorphy-based phylogenetic definition). Importantly, snakes and other tetrapods that do not have digits are nonetheless tetrapods: other characte...	{ "page_id": 5376, "title": "Cladistics" }
earliest members of the Tetrapoda inherit four limbs from a common ancestor, whereas all other vertebrates did not, or at least not homologously? By contrast, for a group within the tetrapods, such as birds, having four limbs is a plesiomorphy. Using these two terms allows a greater precision in the discussion of homol...	{ "page_id": 5376, "title": "Cladistics" }
the potential unreliability of evidence is a problem for any systematic method, or for that matter, for any empirical scientific endeavor at all. Transformed cladistics arose in the late 1970s in an attempt to resolve some of these problems by removing a priori assumptions about phylogeny from cladistic analysis, but i...	{ "page_id": 5376, "title": "Cladistics" }
for the use of paraphyletic groupings, but typically other reasons are quoted. === Horizontal gene transfer === Horizontal gene transfer is the mobility of genetic info between different organisms that can have immediate or delayed effects for the reciprocal host. There are several processes in nature which can cause h...	{ "page_id": 5376, "title": "Cladistics" }
branches; that those stem branches only may have lived for a short time does not affect that assessment in cladistics. == In disciplines other than biology == The comparisons used to acquire data on which cladograms can be based are not limited to the field of biology. Any group of individuals or classes that are hypot...	{ "page_id": 5376, "title": "Cladistics" }
large groups of manuscripts with large numbers of variants that would be impossible to handle manually. It also enables parsimony analysis of contaminated traditions of transmission that would be impossible to evaluate manually in a reasonable period of time. Astrophysics infers the history of relationships between gal...	{ "page_id": 5376, "title": "Cladistics" }
Malonate decarboxylase may refer to: Biotin-independent malonate decarboxylase, an enzyme Biotin-dependent malonate decarboxylase, an enzyme	{ "page_id": 39458049, "title": "Malonate decarboxylase" }
Physical cosmology is a branch of cosmology concerned with the study of cosmological models. A cosmological model, or simply cosmology, provides a description of the largest-scale structures and dynamics of the universe and allows study of fundamental questions about its origin, structure, evolution, and ultimate fate....	{ "page_id": 5378, "title": "Physical cosmology" }
== Modern cosmology developed along tandem tracks of theory and observation. In 1916, Albert Einstein published his theory of general relativity, which provided a unified description of gravity as a geometric property of space and time. At the time, Einstein believed in a static universe, but found that his original fo...	{ "page_id": 5378, "title": "Physical cosmology" }
order to do this. Another method is to measure the brightness of an object and assume an intrinsic luminosity, from which the distance may be determined using the inverse-square law. Due to the difficulty of using these methods, they did not realize that the nebulae were actually galaxies outside our own Milky Way, nor...	{ "page_id": 5378, "title": "Physical cosmology" }
evolved from a hot dense state. The discovery of the cosmic microwave background in 1965 lent strong support to the Big Bang model, and since the precise measurements of the cosmic microwave background by the Cosmic Background Explorer in the early 1990s, few cosmologists have seriously proposed other theories of the o...	{ "page_id": 5378, "title": "Physical cosmology" }
hypothesis is that dark energy is just the vacuum energy, a component of empty space that is associated with the virtual particles that exist due to the uncertainty principle. There is no clear way to define the total energy in the universe using the most widely accepted theory of gravity, general relativity. Therefore...	{ "page_id": 5378, "title": "Physical cosmology" }
photon becomes roughly 10 eV and lower, matter dictates the rate of deceleration and the universe is said to be 'matter dominated'. The intermediate case is not treated well analytically. As the expansion of the universe continues, matter dilutes even further and the cosmological constant becomes dominant, leading to a...	{ "page_id": 5378, "title": "Physical cosmology" }
the universe is 1 / H {\displaystyle 1/H} with H {\displaystyle H} being the Hubble parameter, which varies with time. The expansion timescale 1 / H {\displaystyle 1/H} is roughly equal to the age of the universe at each point in time. === Timeline of the Big Bang === Observations suggest that the universe began around...	{ "page_id": 5378, "title": "Physical cosmology" }
reason, using current particle physics, for the universe to be flat, homogeneous, and isotropic (see the cosmological principle). Moreover, grand unified theories of particle physics suggest that there should be magnetic monopoles in the universe, which have not been found. These problems are resolved by a brief period...	{ "page_id": 5378, "title": "Physical cosmology" }
Bang nucleosynthesis is the theory of the formation of the elements in the early universe. It finished when the universe was about three minutes old and its temperature dropped below that at which nuclear fusion could occur. Big Bang nucleosynthesis had a brief period during which it could operate, so only the very lig...	{ "page_id": 5378, "title": "Physical cosmology" }
isotropic to one part in 105. Cosmological perturbation theory, which describes the evolution of slight inhomogeneities in the early universe, has allowed cosmologists to precisely calculate the angular power spectrum of the radiation, and it has been measured by the recent satellite experiments (COBE and WMAP) and man...	{ "page_id": 5378, "title": "Physical cosmology" }
Understanding the formation and evolution of the largest and earliest structures (i.e., quasars, galaxies, clusters and superclusters) is one of the largest efforts in cosmology. Cosmologists study a model of hierarchical structure formation in which structures form from the bottom up, with smaller objects forming firs...	{ "page_id": 5378, "title": "Physical cosmology" }
from Big Bang nucleosynthesis, the cosmic microwave background, structure formation, and galaxy rotation curves suggests that about 23% of the mass of the universe consists of non-baryonic dark matter, whereas only 4% consists of visible, baryonic matter. The gravitational effects of dark matter are well understood, as...	{ "page_id": 5378, "title": "Physical cosmology" }
orders of magnitude larger than that observed. Steven Weinberg and a number of string theorists (see string landscape) have invoked the 'weak anthropic principle': i.e. the reason that physicists observe a universe with such a small cosmological constant is that no physicists (or any life) could exist in a universe wit...	{ "page_id": 5378, "title": "Physical cosmology" }
to a Big Freeze, or follow some other scenario. === Gravitational waves === Gravitational waves are ripples in the curvature of spacetime that propagate as waves at the speed of light, generated in certain gravitational interactions that propagate outward from their source. Gravitational-wave astronomy is an emerging b...	{ "page_id": 5378, "title": "Physical cosmology" }
The Quest for a New Theory of Cosmic Origins. Random House. ISBN 978-0-224-04448-6. Hawking, Stephen W. (1988). A Brief History of Time: From the Big Bang to Black Holes. Bantam Books, Inc. ISBN 978-0-553-38016-3. Hawking, Stephen W. (2001). The Universe in a Nutshell. Bantam Books, Inc. ISBN 978-0-553-80202-3. Ostrike...	{ "page_id": 5378, "title": "Physical cosmology" }
introduction to cosmology with a thorough discussion of inflation. Mukhanov, Viatcheslav (2005). Physical Foundations of Cosmology. Cambridge University Press. ISBN 978-0-521-56398-7. Padmanabhan, T. (1993). Structure formation in the universe. Cambridge University Press. ISBN 978-0-521-42486-8. Discusses the formation...	{ "page_id": 5378, "title": "Physical cosmology" }
in a far vaster realm?	{ "page_id": 5378, "title": "Physical cosmology" }
Social grooming is a behavior in which social animals, including humans, clean or maintain one another's bodies or appearances. A related term, allogrooming, indicates social grooming between members of the same species. Grooming is a major social activity and a means by which animals who live in close proximity may bo...	{ "page_id": 1840387, "title": "Social grooming" }
been proven to reduce heart rate. Social affiliation during a mild stressor was shown to correlate with lower levels of mammary tumor development and longer lifespan in rats, while lack of this affiliation was demonstrated to be a major risk factor. On the other hand, it could be argued that the hygienic aspect of allo...	{ "page_id": 1840387, "title": "Social grooming" }
on rhesus macaques showed that fMRI scans of the monkeys' brains lit up more significantly at the perirhinial cortex (associated with recognition and memory) and the temporal pole (associated with social and emotional processing/analysis) when the monkeys were shown pictures of their friends' faces, compared to when th...	{ "page_id": 1840387, "title": "Social grooming" }
and used these as a basis to choose grooming mates; they chose grooming mates based on who would reciprocate rather than who would not. More importantly, if the delay between two chimpanzees grooming each other is very little, then the chimpanzees tend to "time match": i.e., the second groomer grooms the first for the ...	{ "page_id": 1840387, "title": "Social grooming" }
and stability. Groups of gibbons with more stable social networks formed grooming networks that were significantly more complex, while groups with low stability networks formed far fewer grooming pairs. ==== Interchange of favours ==== Grooming is often offered by an individual in exchange for a certain behavioral resp...	{ "page_id": 1840387, "title": "Social grooming" }
established between infant survival to one year and a composite sociality index, a measure of sociality based on proximity and social grooming. Evidence has also been provided for the effect of sociality on adult survival in wild baboons. Direct correlations between measures of social connectedness (which focuses on so...	{ "page_id": 1840387, "title": "Social grooming" }
altruism—the behavior itself is a temporary loss of direct fitness (with potential for indirect fitness gain), followed by personal reproduction. This tradeoff has been compared to the Prisoner's Dilemma model, and out of this comparison came Robert Trivers' reciprocal altruism theory under the title "tit-for-tat". In ...	{ "page_id": 1840387, "title": "Social grooming" }
gibbon (Hylobates lar) males were more attentive to social grooming during estrus of the females in their group. Though the behavior of social grooming itself was not beneficial to the one providing the service, the opportunity to mate and subsequent fertilization increases the reproductive fitness of those participati...	{ "page_id": 1840387, "title": "Social grooming" }
a few such instances have been observed in primates. In a 1981 observational study of Japanese macaques at Bucknell University, a mother macaque was seen to choose a stone after observing several stones on the ground, and then use this stone to groom her infant. It was hypothesized that the stone was used as a distract...	{ "page_id": 1840387, "title": "Social grooming" }
learned about social grooming in non-human animals via the study of primates. The driving force behind mammalian social grooming is primarily believed to be rooted in adaptation to consolatory behavior as well as utilitarian purposes in the exchange of resources such as food, sex, and communal hygiene. === Insects === ...	{ "page_id": 1840387, "title": "Social grooming" }
fall asleep while receiving grooming. Conflict among primates has been observed by researchers as increasing stress among the group, making mutual grooming very advantageous. There are benefits to initiating grooming. The one that starts the grooming will in return be groomed themselves, getting the benefit of being cl...	{ "page_id": 1840387, "title": "Social grooming" }
a primate group greater than 40 will face greater ecological problems and, thus, time spent during social grooming is affected. Recent studies regarding chimpanzees have determined the direct correlation of the release of oxytocin to consolatory behavior. This behavior, as well as release, has been noted in primates su...	{ "page_id": 1840387, "title": "Social grooming" }
cows may provide advantages including reduced parasite loads, social tension, and competition at the feed bunk. It is understood that social licking can provide long-term benefits such as promoting positive emotions and a relaxed environment. == Endocrine effects == Social grooming has been shown to be correlated with ...	{ "page_id": 1840387, "title": "Social grooming" }
digestion stimulation. Reproductive benefits have also been found: studies in rats have shown that the release of oxytocin can increase male reproductive success. Oxytocin plays an important role in maternal pair bonding, and is hypothesized to promote similar bonding in social groups as a result of positive feedback l...	{ "page_id": 1840387, "title": "Social grooming" }
increase in maternal grooming resulted in a proportionate increase in glucocorticoid receptors on target tissue in the neonatal rat. In the study on neonatal rats, it was found that the receptor number was altered due to a change in both serotonin and thyroid-stimulating hormone concentrations. An increase in the numbe...	{ "page_id": 1840387, "title": "Social grooming" }
the effects of endogenous opioids. In comparison to the control females, who were given saline solutions, the naloxone females groomed their infants and other members of their group less. The naloxone females were also observed to be less protective of their young, which is uncharacteristic of new mothers. This decline...	{ "page_id": 1840387, "title": "Social grooming" }
5'-Methoxyhydnocarpin (5′-MHC) is a chemical compound that has been isolated from Berberis and Hydnocarpus wightianus. 5′-MHC potentiates the antimicrobial effect of berberine in vitro. == References ==	{ "page_id": 40375557, "title": "5'-Methoxyhydnocarpin" }
In physical cosmology, cosmic inflation, cosmological inflation, or just inflation, is a theory of exponential expansion of space in the very early universe. Following the inflationary period, the universe continued to expand, but at a slower rate. The re-acceleration of this slowing expansion due to dark energy began ...	{ "page_id": 5382, "title": "Cosmic inflation" }
Linde of Stanford, and Paul Steinhardt of Princeton shared the Dirac Prize "for development of the concept of inflation in cosmology". In 2012, Guth and Linde were awarded the Breakthrough Prize in Fundamental Physics for their invention and development of inflationary cosmology. == Overview == Around 1930, Edwin Hubbl...	{ "page_id": 5382, "title": "Cosmic inflation" }
which, by analogy with the more familiar horizon caused by the curvature of Earth's surface, marks the boundary of the part of the Universe that an observer can see. Light (or other radiation) emitted by objects beyond the cosmological horizon in an accelerating universe never reaches the observer, because the space in...	{ "page_id": 5382, "title": "Cosmic inflation" }
of communication. The spatial slices are expanding very fast to cover huge volumes. Things are constantly moving beyond the cosmological horizon, which is a fixed distance away, and everything becomes homogeneous. As the inflationary field slowly relaxes to the vacuum, the cosmological constant goes to zero and space b...	{ "page_id": 5382, "title": "Cosmic inflation" }
the space continues to expand exponentially). In the approximation that the expansion is exactly exponential, the horizon is static and remains a fixed physical distance away. This patch of an inflating universe can be described by the following metric: d s 2 = − ( 1 − Λ r 2 ) c 2 d t 2 + 1 1 − Λ r 2 d r 2 + r 2 d Ω 2 ...	{ "page_id": 5382, "title": "Cosmic inflation" }
so rare that it is quite likely that there are none in the observable universe. Together, these effects are called the inflationary "no-hair theorem" by analogy with the no hair theorem for black holes. The "no-hair" theorem works essentially because the cosmological horizon is no different from a black-hole horizon, e...	{ "page_id": 5382, "title": "Cosmic inflation" }
inflationary phase. When inflation ends, the temperature returns to the pre-inflationary temperature; this is called reheating or thermalization because the large potential energy of the inflaton field decays into particles and fills the Universe with Standard Model particles, including electromagnetic radiation, start...	{ "page_id": 5382, "title": "Cosmic inflation" }
equilibrate. In a big bang with only the matter and radiation known in the Standard Model, two widely separated regions of the observable universe cannot have equilibrated because they move apart from each other faster than the speed of light and thus have never come into causal contact. In the early Universe, it was n...	{ "page_id": 5382, "title": "Cosmic inflation" }
orders of magnitude less than the density of radiation at Big Bang nucleosynthesis, for example). Observations of the cosmic microwave background have demonstrated that the Universe is flat to within a few percent. === Magnetic-monopole problem === Stable magnetic monopoles are a problem for Grand Unified Theories, whi...	{ "page_id": 5382, "title": "Cosmic inflation" }
with a uniform density of matter. Later, Willem de Sitter found a highly symmetric inflating universe, which described a universe with a cosmological constant that is otherwise empty. It was discovered that Einstein's universe is unstable, and that small fluctuations cause it to collapse or turn into a de Sitter univer...	{ "page_id": 5382, "title": "Cosmic inflation" }
metastable false vacuum causing an expanding bubble of true vacuum. ==== The Causal Universe of Brout Englert and Gunzig ==== In 1978 and 1979, Robert Brout, François Englert and Edgard Gunzig suggested that the universe could originate from a fluctuation of Minkowski space which would be followed by a period in which ...	{ "page_id": 5382, "title": "Cosmic inflation" }
the horizon problem, this time in a subfield of particle physics, which led to several speculative attempts to resolve it. In 1980, Alan Guth realized that false vacuum decay in the early universe would solve the problem, leading him to propose a scalar-driven inflation. Starobinsky's and Guth's scenarios both predicte...	{ "page_id": 5382, "title": "Cosmic inflation" }
model was problematic because the model did not reheat properly: when the bubbles nucleated, they did not generate radiation. Radiation could only be generated in collisions between bubble walls. But if inflation lasted long enough to solve the initial conditions problems, collisions between bubbles became exceedingly ...	{ "page_id": 5382, "title": "Cosmic inflation" }
three-week 1982 Nuffield Workshop on the Very Early Universe at Cambridge University. The fluctuations were calculated by four groups working separately over the course of the workshop: Stephen Hawking; Starobinsky; Alan Guth and So-Young Pi; and James Bardeen, Paul Steinhardt and Michael Turner. == Observational statu...	{ "page_id": 5382, "title": "Cosmic inflation" }
the ongoing Sloan Digital Sky Survey. These experiments have shown that the one part in 100,000 inhomogeneities observed have exactly the form predicted by theory. There is evidence for a slight deviation from scale invariance. The spectral index, ns is one for a scale-invariant Harrison–Zel'dovich spectrum. The simple...	{ "page_id": 5382, "title": "Cosmic inflation" }
effect may be due to quantum corrections or new physics, foreground contamination, or even publication bias. An experimental program is underway to further test inflation with more precise CMB measurements. In particular, high precision measurements of the so-called "B-modes" of the polarization of the background radia...	{ "page_id": 5382, "title": "Cosmic inflation" }
of the elementary particles. It is now believed by some that the inflaton cannot be the Higgs field. One problem of this identification is the current tension with experimental data at the electroweak scale,. Other models of inflation relied on the properties of Grand Unified Theories. === Fine-tuning problem === One o...	{ "page_id": 5382, "title": "Cosmic inflation" }
are better models. While inflation depends on quantum field theory (and the semiclassical approximation to quantum gravity) in an important way, it has not been completely reconciled with these theories. Brandenberger commented on fine-tuning in another situation. The amplitude of the primordial inhomogeneities produce...	{ "page_id": 5382, "title": "Cosmic inflation" }
Later that same year, Alexander Vilenkin showed that eternal inflation is generic. Although new inflation is classically rolling down the potential, quantum fluctuations can sometimes lift it to previous levels. These regions in which the inflaton fluctuates upwards, expand much faster than regions in which the inflato...	{ "page_id": 5382, "title": "Cosmic inflation" }
its most vocal critics for this reason. === Initial conditions === Some physicists have tried to avoid the initial conditions problem by proposing models for an eternally inflating universe with no origin. These models propose that while the Universe, on the largest scales, expands exponentially it was, is and always w...	{ "page_id": 5382, "title": "Cosmic inflation" }
is eternal, the probability doesn't matter as long as it is not precisely zero: once it starts, inflation perpetuates itself and quickly dominates the Universe.: 223–225 However, Albrecht and Lorenzo Sorbo argued that the probability of an inflationary cosmos, consistent with today's observations, emerging by a random ...	{ "page_id": 5382, "title": "Cosmic inflation" }
rate of expansion. Therefore, hybrid inflation is not eternal. When the second (slow-rolling) inflaton reaches the bottom of its potential, it changes the location of the minimum of the first inflaton's potential, which leads to a fast roll of the inflaton down its potential, leading to termination of inflation. === Re...	{ "page_id": 5382, "title": "Cosmic inflation" }
singularity with a cosmic contraction and bounce, thereby explaining the initial conditions that led to the big bang. The flatness and horizon problems are naturally solved in the Einstein–Cartan–Sciama–Kibble theory of gravity, without needing an exotic form of matter or free parameters. This theory extends general re...	{ "page_id": 5382, "title": "Cosmic inflation" }
as the temperature at the Big Crunch/Big Bang transition remains below the Grand Unified Scale, as this is the temperature required to produce magnetic monopoles in the first place. As things stand, there is no evidence of any 'slowing down' of the expansion, but this is not surprising as each cycle is expected to last...	{ "page_id": 5382, "title": "Cosmic inflation" }
a variable speed of light have been proposed to resolve the horizon problem of and provide an alternative to cosmic inflation. In the VSL models, the fundamental constant c, denoting the speed of light in vacuum, is greater in the early universe than its present value, effectively increasing the particle horizon at the...	{ "page_id": 5382, "title": "Cosmic inflation" }
to any known physical field, and that its potential energy curve seems to be an ad hoc contrivance to accommodate almost any data obtainable. Paul Steinhardt, one of the founding fathers of inflationary cosmology, calls 'bad inflation' a period of accelerated expansion whose outcome conflicts with observations, and 'go...	{ "page_id": 5382, "title": "Cosmic inflation" }
Wayback Machine Max Tegmark. Our Mathematical Universe (2014), "Chapter 5: Inflation"	{ "page_id": 5382, "title": "Cosmic inflation" }
A composite overwrapped pressure vessel (COPV) is a vessel consisting of a thin, non-structural liner wrapped with a structural fiber composite, designed to hold a fluid under pressure. The liner provides a barrier between the fluid and the composite, preventing leaks (which can occur through matrix microcracks which d...	{ "page_id": 19862791, "title": "Composite overwrapped pressure vessel" }
to autofrettage a vessel is to verify that the volume increase across pressure vessels in a product line remain within an expected range. Larger volume growth than usual could indicate manufacturing defects such as overwrap voids, a high stress gradient through the overwrap layers, or other damage. == Testing == Variou...	{ "page_id": 19862791, "title": "Composite overwrapped pressure vessel" }
Condensed matter physics is the field of physics that deals with the macroscopic and microscopic physical properties of matter, especially the solid and liquid phases, that arise from electromagnetic forces between atoms and electrons. More generally, the subject deals with condensed phases of matter: systems of many c...	{ "page_id": 5387, "title": "Condensed matter physics" }
this list, forming the basis for the more comprehensive specialty of condensed matter physics. The Bell Telephone Laboratories was one of the first institutes to conduct a research program in condensed matter physics. According to the founding director of the Max Planck Institute for Solid State Research, physics profe...	{ "page_id": 5387, "title": "Condensed matter physics" }
environment and Cold War politics of the time. References to "condensed" states can be traced to earlier sources. For example, in the introduction to his 1947 book Kinetic Theory of Liquids, Yakov Frenkel proposed that "The kinetic theory of liquids must accordingly be developed as a generalization and extension of the...	{ "page_id": 5387, "title": "Condensed matter physics" }
the first theoretical model for a classical electron moving through a metallic solid. Drude's model described properties of metals in terms of a gas of free electrons, and was the first microscopic model to explain empirical observations such as the Wiedemann–Franz law.: 27–29 However, despite the success of Drude's mo...	{ "page_id": 5387, "title": "Condensed matter physics" }
Band structure calculations were first used in 1930 to predict the properties of new materials, and in 1947 John Bardeen, Walter Brattain and William Shockley developed the first semiconductor-based transistor, heralding a revolution in electronics. In 1879, Edwin Herbert Hall working at the Johns Hopkins University di...	{ "page_id": 5387, "title": "Condensed matter physics" }
research such as by Bloch on spin waves and Néel on antiferromagnetism led to developing new magnetic materials with applications to magnetic storage devices.: 36–38, g48 === Modern many-body physics === The Sommerfeld model and spin models for ferromagnetism illustrated the successful application of quantum mechanics ...	{ "page_id": 5387, "title": "Condensed matter physics" }
integer multiples of a fundamental constant e 2 / h {\displaystyle e^{2}/h} .(see figure) The effect was observed to be independent of parameters such as system size and impurities. In 1981, theorist Robert Laughlin proposed a theory explaining the unanticipated precision of the integral plateau. It also implied that t...	{ "page_id": 5387, "title": "Condensed matter physics" }

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