NationMaster - Encyclopedia: Big Bang model

In physical cosmology, the Big Bang is the scientific theory that the universe emerged from a tremendously dense and hot state about 13.7 billion years ago. The theory is based on the observations indicating the expansion of space (in accord with the Robertson-Walker model of general relativity) as indicated by the Hubble redshift of distant galaxies taken together with the cosmological principle. Image File history File links Padlock. ... The Big Bang is the scientific theory that the universe expanded rapidly from an enormously dense state some 14 billion years ago. ... According to the Big Bang theory, the universe originated in an infinitely dense singularity. ... According to the Big Bang theory, the universe originated in an infinitely dense singularity. ... The universe from a speculative theoretical physicists point of view can be described as the sum of all matter and energy that exists and the space-time in which they are located and in which all events occur or could occur. ... Cosmology, as a branch of astrophysics, is the study of the large-scale structure of the universe and is concerned with fundamental questions about its formation and evolution. ... Part of a scientific laboratory at the University of Cologne. ... The word theory has a number of distinct meanings in different fields of knowledge, depending on their methodologies and the context of discussion. ... The universe from a speculative theoretical physicists point of view can be described as the sum of all matter and energy that exists and the space-time in which they are located and in which all events occur or could occur. ... Density, or volumic mass (ISO 31), is a measure of mass per volume. ... Fig. ... The metric expansion of space is a key part of sciences current understanding of the universe, whereby space itself is described by a metric which changes over time. ... In mathematics, a metric space is a set where a notion of distance between elements of the set is defined. ... The Friedmann-LemaÃ®tre-Robertson-Walker (FLRW) metric describes a homogeneous, isotropic expanding/contracting universe. ... General relativity (GR) is the geometrical theory of gravitation published by Albert Einstein in 1915/16. ... Hubbles law is the statement in physical cosmology that the redshift in light coming from distant galaxies is proportional to their distance. ... Redshift of spectral lines in the optical spectrum of a supercluster of distant galaxies (right), as compared with that of the Sun (left). ... This article is in need of attention from an expert on the subject. ... NGC 4414, a typical spiral galaxy in the constellation Coma Berenices, is about 56,000 light-years in diameter and approximately 60 million light-years distant. ... The Cosmological Principle is a principle invoked in cosmology that severely restricts the large variety of possible cosmological theories: On large scales, the Universe is homogeneous and isotropic. ...

Extrapolated into the past, these observations show that the universe has expanded from a state in which all the matter and energy in the universe was at an immense temperature and density. Physicists do not widely agree on what happened before this, although general relativity predicts a gravitational singularity (for reporting on some of the more notable speculation on this issue, see cosmogony). In mathematics, extrapolation is the process of constructing new data points outside a discrete set of known data points. ... Observation is an activity of a sapient or sentient living being, which senses and assimiliates the knowledge of a phenomenon in its framework of previous knowledge and ideas. ... This article or section does not cite its references or sources. ... Physics (from the Greek, (phÃºsis), nature and (phusikÃ©), knowledge of nature) is the science concerned with the discovery and understanding of the fundamental laws which govern matter, energy, space, and time. ... This article or section is in need of attention from an expert on the subject. ... To meet Wikipedias quality standards, this article or section may require cleanup. ...

The term Big Bang is used both in a narrow sense to refer to a point in time when the observed expansion of the universe (Hubble's law) began — calculated to be 13.7 billion (1.37 × 10¹⁰) years ago (±2%) — and in a more general sense to refer to the prevailing cosmological paradigm explaining the origin and expansion of the universe, as well as the composition of primordial matter through nucleosynthesis as predicted by the Alpher-Bethe-Gamow theory.^[1] Hubbles law is the statement in physical cosmology that the redshift in light coming from distant galaxies is proportional to their distance. ... One thousand million (1,000,000,000) is the natural number following 999,999,999 and preceding 1,000,000,001. ... To help compare orders of magnitude of different times this page lists times between 1017 seconds and 1018 seconds (3. ... Since the late 1960s, the word paradigm (IPA: ) has referred to a thought pattern in any scientific discipline or other epistemological context. ... Nucleosynthesis is the process of creating new atomic nuclei from preexisting nucleons (protons and neutrons). ... In cosmology, the Alpher-Bethe-Gamow theory (or Î±Î²Î³ theory) was created by Ralph Alpher, at the time a physics PhD student, and his advisor George Gamow. ...

From this model, George Gamow in 1948 was able to predict, at least qualitatively, the existence of cosmic microwave background radiation (CMB).^[2] The CMB was discovered in 1964^[3] and further corroborated the Big Bang theory, giving it an additional advantage over its chief rival, the steady state theory.^[4] An abstract model (or conceptual model) is a theoretical construct that represents physical, biological or social processes, with a set of variables and a set of logical and quantitative relationships between them. ... George Gamow (pronounced GAM-off) (March 4, 1904 â€“ August 19, 1968) , born Georgiy Antonovich Gamov (Ð“ÐµÐ¾Ñ€Ð³Ð¸Ð¹ ÐÐ½Ñ‚Ð¾Ð½Ð¾Ð²Ð¸Ñ‡ Ð“Ð°Ð¼Ð¾Ð²) was a Ukrainian born physicist and cosmologist. ... In cosmology, the cosmic microwave background radiation (most often abbreviated CMB but occasionally CMBR, CBR or MBR, also referred as relic radiation) is a form of electromagnetic radiation discovered in 1965 that fills the entire universe. ... In cosmology, the steady state theory (also known as the Infinite Universe Theory or continuous creation) is a model developed in 1948 by Fred Hoyle, Thomas Gold, Hermann Bondi and others as an alternative to the Big Bang theory (known, usually, as the standard cosmological model). ...

Cosmology, as a branch of astrophysics, is the study of the large-scale structure of the universe and is concerned with fundamental questions about its formation and evolution. ... Image File history File links Download high resolution version (2198x1274, 1278 KB)WMAP map of CMB anisotropy, from NASA.gov File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... The age of the universe, according to the Big Bang theory, is defined as the largest possible value of proper time integrated along a time-like curve from the Earth at the present epoch back to the Big Bang. The time that has elapsed on a hypothetical clock which has... The comoving distance or conformal distance of two objects in the universe is the distance divided by a time-varying scale factor representing the expansion of the universe. ... In cosmology, the cosmic microwave background radiation (most often abbreviated CMB but occasionally CMBR, CBR or MBR, also referred as relic radiation) is a form of electromagnetic radiation discovered in 1965 that fills the entire universe. ... In physical cosmology, dark energy is a hypothetical form of energy that permeates all of space and has strong negative pressure. ... Dark matter is a term used in astrophysics to refer to that component of the universe that is unaccounted for, unexplained or inconclusively explained, and whose existence at this time is only inferred. ... // The Friedmann-LemaÃ®tre-Robertson-Walker (FLRW) metric is an exact solution of the Einstein field equations of general relativity and which describes a homogeneous, isotropic expanding/contracting universe. ... The Friedmann equations relate various cosmological parameters within the context of general relativity. ... In astrophysics, the questions of galaxy formation and evolution are: How, from a homogeneous universe, did we obtain the very heterogeneous one we live in? How did galaxies form? How do galaxies change over time? A spectacular head-on collision between two galaxies is seen in this NASA Hubble Space... Hubbles law is the statement in physical cosmology that the redshift in light coming from distant galaxies is proportional to their distance. ... Astronomy and cosmology examine the universe to understand the large-scale structure of the cosmos. ... A pie chart indicating the proportional composition of different energy-density components of the universe. ... The metric expansion of space is a key part of sciences current understanding of the universe, whereby space itself is described by a metric which changes over time. ... In cosmology, Big Bang nucleosynthesis (or primordial nucleosynthesis) refers to the production of nuclei other than H-1, the normal, light hydrogen, during the early phases of the universe, shortly after the Big Bang. ... The observable Universe is a term used in cosmology to describe a ball-shaped region of space surrounding the Earth that is close enough that we might observe objects in it. ... Redshift of spectral lines in the optical spectrum of a supercluster of distant galaxies (right), as compared with that of the Sun (left). ... The shape of the Universe is an informal name for a subject of investigation within physical cosmology. ... It has been suggested that this article or section be merged into Large-scale structure of the cosmos. ... A graphical timeline is available here: Graphical timeline of the Big Bang This timeline of the Big Bang describes the events that have occurred and will occur according to the scientific theory of the Big Bang. ... This timeline of the Big Bang shows the sequence of events as predicted by the Big Bang theory, from the beginning of the Planck Epoch to the end of the Epoch of Nucleosynthesis (and beginning of the Epoch of Galaxies). ... The timeline of cosmology lists the sequence of cosmological theories and discoveries in chronological order. ... The ultimate fate of our universe is a topic in physical cosmology. ... The universe from a speculative theoretical physicists point of view can be described as the sum of all matter and energy that exists and the space-time in which they are located and in which all events occur or could occur. ... Spiral Galaxy ESO 269-57 Astrophysics is the branch of astronomy that deals with the physics of the universe, including the physical properties (luminosity, density, temperature, and chemical composition) of celestial objects such as stars, galaxies, and the interstellar medium, as well as their interactions. ... General relativity (GR) is the geometrical theory of gravitation published by Albert Einstein in 1915/16. ... Thousands of particles explode from the collision point of two relativistic (100 GeV per nucleon) gold ions in the STAR detector of the Relativistic Heavy Ion Collider. ... This article or section does not cite its references or sources. ...

History

The Big Bang theory developed from observations of the structure of the universe and from theoretical considerations. Observers determined that most "spiral nebulae" were receding from Earth, but did not grasp the cosmological implications of this fact, or realize that the supposed nebulae were galaxies outside our Milky Way.^[5] Georges Lemaître, a Belgian Roman Catholic priest, independently derived the Friedmann-Lemaître-Robertson-Walker equations from Albert Einstein's equations of general relativity in 1927 and proposed, on the basis of the recession of spiral nebulae, that the universe began as a simple "primeval atom"—now known as the Big Bang.^[6] The history of the Big Bang theory begins with the Big Bangs development from observations and theoretical considerations. ... The timeline of cosmology lists the sequence of cosmological theories and discoveries in chronological order. ... The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Î“Î±Î»Î±Î¾Î¯Î±Ï‚ (Galaxias), sometimes referred to simply as the Galaxy), is a barred spiral galaxy of the Local Group. ... Father Georges-Henri LemaÃ®tre (July 17, 1894 â€“ June 20, 1966) was a Belgian Roman Catholic priest, honorary prelate, professor of physics and astronomer. ... The Friedmann equations relate various cosmological parameters within the context of general relativity. ... Albert Einstein ( ) (March 14, 1879 â€“ April 18, 1955) was a German-born theoretical physicist widely considered one of the greatest physicists of all time. ... For other topics related to Einstein see Einstein (disambig) In physics, the Einstein field equation or the Einstein equation is a tensor equation in the theory of gravitation. ... General relativity (GR) is the geometrical theory of gravitation published by Albert Einstein in 1915/16. ... The Triangulum Emission Nebula NGC 604 lies in a spiral arm of Galaxy M33, 2. ... Atomic redirects here. ...

Edwin Hubble provided an observational basis for Lemaître's theory two years later. He discovered that, seen from Earth, light from other galaxies is redshifted proportionally to their distance from Earth -- a fact now known as Hubble's law.^[7]^[8] Given the cosmological principle whereby the universe, when viewed on sufficiently large distance scales, has no preferred directions or preferred places, Hubble's law implied that the universe was expanding, contradicting the infinite and unchanging static universe scenario developed by Einstein.^[9] Edwin Hubble Edwin Powell Hubble (November 20, 1889 â€“ September 28, 1953) was an American astronomer, noted for his discovery of galaxies beyond the Milky Way and the cosmological redshift. ... Redshift of spectral lines in the optical spectrum of a supercluster of distant galaxies (right), as compared with that of the Sun (left). ... Hubbles law is the statement in physical cosmology that the redshift in light coming from distant galaxies is proportional to their distance. ... The Cosmological Principle is a principle invoked in cosmology that severely restricts the large variety of possible cosmological theories: On large scales, the Universe is homogeneous and isotropic. ... Basic description The theory of a static universe is the rival theory to an expanding universe and all of its subvarieties. ...

Two distinct possibilities emerged. One was Fred Hoyle's steady state model, whereby new matter would be created as the universe seemed to expand. In this model, the universe is roughly the same at any point in time.^[10] The other was Lemaître's Big Bang theory, advocated and developed by George Gamow. Hoyle actually coined the name of Lemaître's theory, referring to it sarcastically as "this big bang idea" during a program broadcast on March 28, 1949, by the BBC Third Programme. Hoyle repeated the term in further broadcasts in early 1950, as part of a series of five lectures entitled The Nature of Things. The text of each lecture was published in The Listener a week after the broadcast, the first time that the term "big bang" appeared in print.^[11] While Hoyle's "steady state" and Lemaître's "Big Bang" were the two most popular models used to explain Hubble's observations, other ideas were also proposed. Some of these alternatives included the Milne model,^[12] Richard Tolman's oscillatory universe,^[13] and Fritz Zwicky's tired light hypothesis.^[14] WMAP satellite artist depiction from NASA Believed to be in the public domain. ... WMAP satellite artist depiction from NASA Believed to be in the public domain. ... Artist depiction of the WMAP satellite at the L2 point The Wilkinson Microwave Anisotropy Probe (WMAP) is a NASA satellite whose mission is to survey the sky to measure the temperature of the radiant heat left over from the Big Bang. ... Sir Fred Hoyle (June 24, 1915 in Bingley, Yorkshire â€“ August 20, 2001 in Bournemouth, England) was a British astronomer, notable for a number of his theories that run counter to current astronomical opinion, and a writer of science fiction, including a number of books co-authored by his son Geoffrey... For alternative meanings see steady state (disambiguation). ... George Gamow (pronounced GAM-off) (March 4, 1904 â€“ August 19, 1968) , born Georgiy Antonovich Gamov (Ð“ÐµÐ¾Ñ€Ð³Ð¸Ð¹ ÐÐ½Ñ‚Ð¾Ð½Ð¾Ð²Ð¸Ñ‡ Ð“Ð°Ð¼Ð¾Ð²) was a Ukrainian born physicist and cosmologist. ... March 28 is the 87th day of the year in the Gregorian Calendar (88th in leap years). ... 1949 (MCMXLIX) was a common year starting on Saturday (the link is to a full 1949 calendar). ... The British Broadcasting Corporation, usually known as the BBC (and also informally known as the Beeb or Auntie) is one of the largest broadcasting corporations in the world in terms of audience numbers, employing 26,000 staff in the UK alone and with a budget of more than Â£4 billion. ... The BBC Third Programme was the third national radio network broadcast by the BBC, has since become Radio 3, but was originally known (at least within the BBC) as C. The other two were the Home Service (mainly speech based) and the Light Programme, dedicated to light music, usually cover... The Listener was a weekly magazine established by the BBC under Lord Reith in January 1929. ... A non-standard cosmology is a cosmological idea that contradicts the standard model of cosmology. ... Milnes model follows the description from special relativity of an observable universes spacetime diagram containing past and future light cones along with elsewhere in spacetime. ... Richard C. Tolman was California Institute of Technology professor of physical chemistry and mathematical physics. ... The oscillatory universe is the hypothesis, attributable to Richard Tolman, that the universe undergoes an infinite series of oscillations, each beginning with a big bang and ending with a big crunch. ... Fritz Zwicky (February 14, 1898 â€“ February 8, 1974) was an American-based Swiss astronomer. ... Tired Light (a. ...

For a while, support was split between the "steady state" and "Big Bang" theories. However, the observational evidence eventually began to favor the latter. The discovery of the cosmic microwave background radiation in 1964 secured its place as the best theory of the origin and evolution of the cosmos. Much of the current work in cosmology includes understanding how galaxies form in the context of the Big Bang, understanding what happened at the Big Bang and reconciling observations with the basic theory. In cosmology, the cosmic microwave background radiation (most often abbreviated CMB but occasionally CMBR, CBR or MBR, also referred as relic radiation) is a form of electromagnetic radiation discovered in 1965 that fills the entire universe. ...

Huge advances in Big Bang cosmology were made in the late 1990s and the early 21st century as a result of major advances in telescope technology in combination with large amounts of satellite data such as that from COBE, the Hubble Space Telescope and WMAP. Such data have allowed cosmologists to calculate many of the parameters of the Big Bang to a new level of precision and led to the unexpected discovery that the expansion of the universe appears to be accelerating. (See dark energy.) 50 cm refracting telescope at Nice Observatory. ... The Cosmic Background Explorer (COBE), also referred to as Explorer 66, was the first satellite built dedicated to cosmology. ... The Hubble Space Telescope (HST) is a telescope in orbit around the Earth, named after astronomer Edwin Hubble for his discovery of galaxies outside the Milky Way and his creation of Hubbles Law, which calculates the rate at which the universe is expanding. ... Artist depiction of the WMAP satellite at the L2 point The Wilkinson Microwave Anisotropy Probe (WMAP) is a NASA satellite whose mission is to survey the sky to measure the temperature of the radiant heat left over from the Big Bang. ... In physical cosmology, dark energy is a hypothetical form of energy that permeates all of space and has strong negative pressure. ...

Overview

Based on measurements of the expansion of the universe using Type 1a supernovae, measurements of temperature fluctuations in the cosmic microwave background, and measurements of the correlation function of galaxies, the universe has a calculated age of 13.7 ± 0.2 billion years. The agreement of these three independent measurements is considered strong evidence for the so-called ΛCDM model that describes the detailed nature of the contents of the universe. A graphical timeline is available here: Graphical timeline of the Big Bang This timeline of the Big Bang describes the events that have occurred and will occur according to the scientific theory of the Big Bang. ... Image File history File links Timeline_icon. ... This timeline of the Big Bang shows the sequence of events as predicted by the Big Bang theory, from the beginning of the Planck Epoch to the end of the Epoch of Nucleosynthesis (and beginning of the Epoch of Galaxies). ... Remnant of Keplers Supernova, SN 1604. ... In cosmology, the cosmic microwave background radiation (most often abbreviated CMB but occasionally CMBR, CBR or MBR, also referred as relic radiation) is a form of electromagnetic radiation discovered in 1965 that fills the entire universe. ... For stochastic processes, including those that arise in statistical mechanics and Euclidean quantum field theory, a correlation function is the correlation between random variables at two different points in space or time. ... The age of the universe, according to the Big Bang theory, is defined as the largest possible value of proper time integrated along a time-like curve from the Earth at the present epoch back to the Big Bang. The time that has elapsed on a hypothetical clock which has... To help compare orders of magnitude of different times this page lists times between 1017 seconds and 1018 seconds (3. ... A pie chart indicating the proportional composition of different energy-density components of the universe. ...

The early universe was filled homogeneously and isotropically with an incredibly high energy density and concomitantly huge temperatures and pressures. It expanded and cooled, going through phase transitions pertinent to elementary particles. Fig. ... The use of water pressure - the Captain Cook Memorial Jet in Lake Burley Griffin, Canberra. ... In physics, a phase transition, (or phase change) is the transformation of a thermodynamic system from one phase to another. ...

Approximately 10⁻³⁵ seconds after the Planck epoch a phase transition caused the universe to experience exponential growth during a period called cosmic inflation. After inflation stopped, the material components of the universe were in the form of a quark-gluon plasma (also including all other particles—and perhaps experimentally produced recently as a quark-gluon liquid [3]) in which the constituent particles were all moving relativistically. As the universe continued growing in size, the temperature dropped. At a certain temperature, by an as-yet-unknown transition called baryogenesis, the quarks and gluons combined into baryons such as protons and neutrons, somehow producing the observed asymmetry between matter and antimatter. Still lower temperatures led to further symmetry breaking phase transitions that put the forces of physics and elementary particles into their present form. Later, some protons and neutrons combined to form the universe's deuterium and helium nuclei in a process called Big Bang nucleosynthesis. As the universe cooled, matter gradually stopped moving relativistically and its rest mass energy density came to gravitationally dominate that of radiation. After about 300,000 years the electrons and nuclei combined into atoms (mostly hydrogen); hence the radiation decoupled from matter and continued through space largely unimpeded. This relic radiation is the cosmic microwave background. Named after Max Planck, in cosmology the Planck epoch (or Planck Era) is the earliest period of time in the history of the universe, from zero to 10-43 seconds (one Planck time), during which all four fundamental forces were unified and elementary particles did not yet exist. ... In mathematics, a quantity that grows exponentially is one whose growth rate is always proportional to its current size. ... In physical cosmology, cosmic inflation is the idea that the nascent universe passed through a phase of exponential expansion that was driven by a negative-pressure vacuum energy density. ... A QGP is formed at the collision point of two relativistically accelerated gold ions in the center of the STAR detector at the relativistic heavy ion collider at the Brookhaven national laboratory. ... Albert Einsteins theory of relativity is a set of two theories in physics: special relativity and general relativity. ... Baryogenesis is the generic designation for the physical processes that generate matter (more specifically, a class of fundamental particle called baryon) from an otherwise matter-empty state (such as it is generally believed to be the state of the Universe at its onset, the so-called Big Bang). ... In particle physics, the baryons are a family of subatomic particles including the proton and the neutron (collectively called nucleons), as well as a number of unstable, heavier particles (called hyperons). ... Symmetry is a characteristic of geometrical shapes, equations and other objects; we say that such an object is symmetric with respect to a given operation if this operation, when applied to the object, does not appear to change it. ... This article or section does not cite its references or sources. ... In particle physics, antimatter extends the concept of the antiparticle to matter, wherein if a particle and its antiparticle come into contact with each other, the two annihilate â€”that is, they may both be converted into other particles with equal energy in accordance with Einsteins equation E = mc2. ... Promotional picture Symmetry Breaking is a rock band from Northern New Jersey, in the United States. ... A fundamental interaction is a mechanism by which particles interact with each other, and which cannot be explained by another more fundamental interaction. ... Thousands of particles explode from the collision point of two relativistic (100 GeV per nucleon) gold ions in the STAR detector of the Relativistic Heavy Ion Collider. ... Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of planet Earth of approximately one atom in 6500 of hydrogen (~154 PPM). ... General Name, Symbol, Number helium, He, 2 Chemical series noble gases Group, Period, Block 18, 1, s Appearance colorless Atomic mass 4. ... A semi-accurate depiction of the helium atom. ... In cosmology, Big Bang nucleosynthesis (or primordial nucleosynthesis) refers to the production of nuclei other than H-1, the normal, light hydrogen, during the early phases of the universe, shortly after the Big Bang. ... The term mass in special relativity is used in a couple of different ways, occasionally leading to a great deal of confusion. ... Gravity is a force of attraction that acts between bodies that have mass. ... Electromagnetic radiation can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields. ... General Name, Symbol, Number hydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1, 1, s Appearance colorless Atomic mass 1. ... In physics, decoupling is the general phenomenon in which the interactions between some physical objects (such as elementary particles) disappear. ...

Over time, the slightly denser regions of the nearly uniformly distributed matter gravitationally attracted nearby matter and thus grew even denser, forming gas clouds, stars, galaxies, and the other astronomical structures observable today. The details of this process depend on the amount and type of matter in the universe. The three possible types are known as cold dark matter, hot dark matter, and baryonic matter. The best measurements available (from WMAP) show that the dominant form of matter in the universe is cold dark matter. The other two types of matter make up less than 20% of the matter in the universe. This article is about the astronomical object. ... Cold dark matter (or CDM) is a refinement of the big bang theory that contains the additional assumption that most of the matter in the Universe consists of material which cannot be observed by its electromagnetic radiation and hence is dark while at the same time the particles making up... Hot dark matter is a form of dark matter, which consists of particles that travel with relativistic velocities. ... In particle physics, the baryons are a family of subatomic particles including the proton and the neutron (collectively called Greek barys, meaning heavy, as they are heavier than the other main groups of particles. ... Artist depiction of the WMAP satellite at the L2 point The Wilkinson Microwave Anisotropy Probe (WMAP) is a NASA satellite whose mission is to survey the sky to measure the temperature of the radiant heat left over from the Big Bang. ...

The universe today appears to be dominated by a mysterious form of energy known as dark energy. Approximately 70% of the total energy density of today's universe is in this form. This dark energy causes the expansion of the universe to deviate from a linear velocity-distance relationship, observed as a faster than expected expansion at very large distances. Dark energy in its simplest formulation takes the form of a cosmological constant term in Einstein's field equations of general relativity, but its composition is unknown and, more generally, the details of its equation of state and relationship with the standard model of particle physics continue to be investigated both observationally and theoretically. In physical cosmology, dark energy is a hypothetical form of energy that permeates all of space and has strong negative pressure. ... Hubbles law is the statement in physical cosmology that the redshift in light coming from distant galaxies is proportional to their distance. ... The cosmological constant (usually denoted by the Greek capital letter lambda: Î›) was proposed by Albert Einstein as part of his theory of general relativity to achieve a stationary universe. ... In physics, the Einstein field equation or Einstein equation is a differential equation in Einsteins theory of general relativity. ... In cosmology, the equation of state of a perfect fluid is characterized by a dimensionless number w, equal to the ratio of its pressure p to its energy density ρ: . It is closely related to the thermodynamic equation of state and ideal gas law. ... The Standard Model of Fundamental Particles and Interactions For the Standard Model in Cryptography, see Standard Model (cryptography). ...

All these observations are encapsulated in the ΛCDM model of cosmology, which is a mathematical model of the Big Bang with six free parameters. Mysteries appear as one looks closer to the beginning, when particle energies were higher than can yet be studied by experiment. There is no compelling physical model for the first 10⁻³³ seconds of the universe, before the phase transition that grand unification theory predicts. At the "first instant", Einstein's theory of gravitation predicts a gravitational singularity where densities become infinite.^[15] To resolve this paradox, a theory of quantum gravitation is needed. Understanding this period of the history of the universe is one of the greatest unsolved problems in physics. A pie chart indicating the proportional composition of different energy-density components of the universe. ... A mathematical model is an abstract model that uses mathematical language to describe the behaviour of a system. ... It has been suggested that this article or section be merged into Unified field theory. ... This article or section is in need of attention from an expert on the subject. ... A physical paradox is an apparent contradiction relating to physical descriptions of the universe. ... This article or section does not cite its references or sources. ... To meet Wikipedias quality standards, this article or section may require cleanup. ...

Theoretical underpinnings

These ideas were initially taken as postulates, but today there are efforts to test each of them. Tests of the universality of physical laws have found that the largest possible deviation of the fine structure constant over the age of the universe is of order 10^-5.^[16] The isotropy of the universe that defines the Cosmological Principle has been tested to a level of 10^-5 and the universe has been measured to be homogeneous on the largest scales to the 10% level.^[17] There are efforts to test the Copernican Principle by looking at the interaction of galaxy groups and clusters with the CMB through the Sunyaev-Zel'dovich effect to a level of 1% accuracy.^[18] A physical law, scientific law, or a law of nature is a scientific generalization based on empirical observations of physical behavior. ... The Cosmological Principle is a principle invoked in cosmology that severely restricts the large variety of possible cosmological theories: On large scales, the Universe is homogeneous and isotropic. ... The Copernican principle is the philosophical statement that no special observers should be proposed. ... The fine-structure constant or Sommerfeld fine-structure constant, usually denoted , is the fundamental physical constant characterizing the strength of the electromagnetic interaction. ... Isotropy (the opposite of anisotropy) is the property of being independent of direction. ... The galaxies of HCG 87, about four hundred million light-years distant. ... The Sunyaev-Zeldovich effect (SZ effect or Sunyaev-Zeldovich theory) is due to high energy electrons distorting the cosmic microwave background radiation (CMB) through the inverse Compton effect, in which some of the high energy of the electrons is transferred to the low energy photons. ...

These assumptions, combined with Einstein's theory of general relativity, imply that spacetime should be described by a homogeneous and isotropic metric, which must therefore be a FRW metric. These metrics rely on a coordinate chart or grid being laid down over all spacetime, with which we can specify the location of points (e.g., galaxies, stars...) in the universe. The specific chart used is called a comoving coordinate system, since the grid is designed to expand along with the universe, and so objects that are carried along by the expansion of the universe remain at fixed points on the grid. While their coordinate distance (comoving distance) remains constant, the physical distance between two such comoving points expands proportionally with the scale factor of the universe. See also metric expansion of space. Einstein redirects here. ... General relativity (GR) is the geometrical theory of gravitation published by Albert Einstein in 1915/16. ... In physics, spacetime is a mathematical model that combines three-dimensional space and one-dimensional time into a single construct called the space-time continuum, in which time plays the role of the 4th dimension. ... Look up Homogeneous in Wiktionary, the free dictionary. ... Isotropic means independent of direction. Isotropic radiation has the same intensity regardless of the direction of measurement, and an isotropic field exerts the same action regardless of how the test particle is oriented. ... In mathematics, the metric tensor is a symmetric tensor field of rank 2 that is used to measure distance in a space. ... The Friedmann-LemaÃ®tre-Robertson-Walker (FLRW) metric describes a homogeneous, isotropic expanding/contracting universe. ... In topology, an atlas describes how a complicated space is glued together from simpler pieces. ... In physics, spacetime is a mathematical model that combines three-dimensional space and one-dimensional time into a single construct called the space-time continuum, in which time plays the role of the 4th dimension. ... The comoving distance or conformal distance of two objects in the universe is the distance divided by a time-varying scale factor representing the expansion of the universe. ... The comoving distance or conformal distance of two objects in the universe is the distance divided by a time-varying scale factor representing the expansion of the universe. ... A scale factor is a number which scales some quantity. ... The metric expansion of space is a key part of sciences current understanding of the universe, whereby space itself is described by a metric which changes over time. ...

As the universe can be described by such coordinates, the Big Bang is not an explosion of matter moving outward to fill an empty universe; space itself expanded and caused the physical distance between two comoving points to increase. Objects that are bound together (such as atoms, people, stars, the solar system, and galaxies) do not expand with spacetime's expansion because the forces that bind them together are strong compared with the Hubble expansion that is pulling them apart. The metric expansion of space is a key part of sciences current understanding of the universe, whereby space itself is described by a metric which changes over time. ... Atomic redirects here. ... This article is about the astronomical object. ... Major features of the Solar System (not to scale, from left to right): Pluto, Neptune, Uranus, Saturn, a comet, Jupiter, Ceres which lies in the asteroid belt, the Sun, Mercury, Venus, Earth & Moon, and Mars. ... This article is about a celestial body. ...

One can also define a conformal time

η

, in which case the full spacetime metric takes the form of a static metric multiplied by an overall scale factor. The conformal time coordinate is quite useful since the comoving distance traveled by a light ray is equal to the conformal time interval of the trip. This enables understanding of the causal structure of spacetime. For example, the Big Bang occurred at a finite interval of conformal time

η 0

to the past. Objects whose comoving distance is greater than

c η 0

are too far away for light to have had time to travel to us since the Big Bang: therefore we cannot see all of the past universe and there is a past horizon. If the universe is accelerating, then there is only a finite amount of conformal time

η F

to the future (though this finite amount of conformal time corresponds to an infinite amount of clock or proper time). Objects located at comoving distances further than

c η F

can never be reached by a light ray emitted by us today, therefore we cannot influence all of the future universe and there is a future horizon. See also cosmological horizon. The particle horizon in cosmology is the distance from which particles (of positive mass or of zero mass) can have travelled to the observer in the age of the Universe. ... A scale factor is a number which scales some quantity. ... The comoving distance or conformal distance of two objects in the universe is the distance divided by a time-varying scale factor representing the expansion of the universe. ... The Accelerating universe is the idea that our universe is undergoing accelerated expansion: distant objects are receding from our galaxy with speeds that increase over time. ... Proper time is time as measured by the clock for an observer who is traveling through spacetime. ... In cosmology, a cosmological horizon marks a limit to observability, and marks the boundary of a region that an observer cannot see into directly due to cosmological effects. ...

Observational evidence

It is generally stated that there are three observational pillars that support the Big Bang theory of cosmology. These are the Hubble-type expansion seen in the redshifts of galaxies, the detailed measurements of the cosmic microwave background, and the abundance of light elements. (See Big Bang nucleosynthesis.) Additionally, the observed correlation function of large-scale structure of the cosmos fits well with standard Big Bang theory. Hubbles law is the statement in physical cosmology that the redshift in light coming from distant galaxies is proportional to their distance. ... Redshift of spectral lines in the optical spectrum of a supercluster of distant galaxies (right), as compared with that of the Sun (left). ... In cosmology, Big Bang nucleosynthesis (or primordial nucleosynthesis) refers to the production of nuclei other than H-1, the normal, light hydrogen, during the early phases of the universe, shortly after the Big Bang. ... Astronomers describe the distribution of galaxies in the universe by means of a correlation function. ... Astronomy and cosmology examine the universe to understand the large-scale structure of the cosmos. ...

Hubble's law expansion

Observations of distant galaxies and quasars show that these objects are redshifted, meaning that the light emitted from them has been shifted to longer wavelengths. This is seen by taking a frequency spectrum of the objects and then matching the spectroscopic pattern of emission lines or absorption lines corresponding to atoms of the chemical elements interacting with the light. From this analysis, a redshift corresponding to a Doppler shift for the radiation can be measured which is explained by a recessional velocity. When the recessional velocities are plotted against the distances to the objects, a linear relationship, known as Hubble's law, is observed: Hubbles law is the statement in physical cosmology that the redshift in light coming from distant galaxies is proportional to their distance. ... Image File history File links HubbleData. ... Image File history File links HubbleData. ... Artists impression of quasar GB1508 A quasar (contraction of QUASi-stellAR radio source) is an astronomical source of electromagnetic energy, including light, which shows a very high redshift. ... Redshift of spectral lines in the optical spectrum of a supercluster of distant galaxies (right), as compared with that of the Sun (left). ... Prism splitting light Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of any wavelength[1]. The elementary particle that defines light is the photon. ... Familiar concepts associated with a frequency are colors, musical notes, radio/TV channels, and even the regular rotation of the earth. ... Extremely high resolution spectrum of the Sun showing thousands of elemental absorption lines (fraunhofer lines) Spectroscopy is the study of matter and its properties by investigating light, sound, or particles that are emitted, absorbed or scattered by the matter under investigation. ... A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range, compared with the nearby frequencies. ... A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range, compared with the nearby frequencies. ... Atomic redirects here. ... The periodic table of the chemical elements A chemical element, often called simply an element, is a substance that cannot be decomposed or transformed into other chemical substances by ordinary chemical processes. ... Redshift of spectral lines in the optical spectrum of a supercluster of distant galaxies (right), as compared with that of the Sun (left). ... The Doppler effect is the apparent change in frequency or wavelength of a wave that is perceived by an observer moving relative to the source of the waves. ... The velocity of an object is simply its speed in a particular direction. ... Hubbles law is the statement in physical cosmology that the redshift in light coming from distant galaxies is proportional to their distance. ...

The Hubble's law observation has two possible explanations. One is that we are at the center of an explosion of galaxies, a position which is untenable given the Copernican principle. The second explanation is that the universe is uniformly expanding everywhere as a unique property of spacetime. This type of universal expansion was developed mathematically in the context of general relativity well before Hubble made his analysis and observations, and it remains the cornerstone of the Big Bang theory as developed by Friedmann-Lemaître-Robertson-Walker. The velocity of an object is simply its speed in a particular direction. ... NGC 4414, a typical spiral galaxy in the constellation Coma Berenices, is about 56,000 light-years in diameter and approximately 60 million light-years distant. ... A kilometre (American spelling: kilometer) (symbol: km) is a unit of length equal to 1000 metres (from the Greek words khilia = thousand and metro = count/measure). ... This article is about the unit of time. ... The megaparsec (abbreviated Mpc) is a unit of distance used in astronomy, equal to one million parsecs. ... Artist depiction of the WMAP satellite at the L2 point The Wilkinson Microwave Anisotropy Probe (WMAP) is a NASA satellite whose mission is to survey the sky to measure the temperature of the radiant heat left over from the Big Bang. ... Hubbles law is the statement in physical cosmology that the redshift in light coming from distant galaxies is proportional to their distance. ... The Copernican principle is the philosophical statement that no special observers should be proposed. ... The scale factor, parameter of Friedmann-LemaÃ®tre-Robertson-Walker model, is a function of time which represents the relative expansion of the universe. ... In physics, spacetime is a mathematical model that combines three-dimensional space and one-dimensional time into a single construct called the space-time continuum, in which time plays the role of the 4th dimension. ... General relativity (GR) is the geometrical theory of gravitation published by Albert Einstein in 1915/16. ... The Friedmann-LemaÃ®tre-Robertson-Walker (FLRW) metric describes a homogeneous, isotropic expanding/contracting universe. ...

Cosmic microwave background radiation

The Big Bang theory predicted the existence of the cosmic microwave background radiation, or CMB, which is composed of photons first emitted during baryogenesis. Because the early universe was in thermal equilibrium, the temperature of the radiation and the plasma were equal until the plasma recombined. Before atoms formed, radiation was constantly absorbed and re-emitted in a process called Compton scattering: the early universe was opaque to light. However, cooling due to the expansion of the universe allowed the temperature to eventually fall below 3,000 K, at which point electrons and nuclei combined to form atoms and the primordial plasma turned into a neutral gas in a process called photon decoupling. A universe with only neutral atoms allows radiation to travel largely unimpeded. In cosmology, the cosmic microwave background radiation (most often abbreviated CMB but occasionally CMBR, CBR or MBR, also referred as relic radiation) is a form of electromagnetic radiation discovered in 1965 that fills the entire universe. ... Image File history File links Download high resolution version (2198x1274, 1278 KB)WMAP map of CMB anisotropy, from NASA.gov File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Download high resolution version (2198x1274, 1278 KB)WMAP map of CMB anisotropy, from NASA.gov File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Artist depiction of the WMAP satellite at the L2 point The Wilkinson Microwave Anisotropy Probe (WMAP) is a NASA satellite whose mission is to survey the sky to measure the temperature of the radiant heat left over from the Big Bang. ... In cosmology, the cosmic microwave background radiation (most often abbreviated CMB but occasionally CMBR, CBR or MBR, also referred as relic radiation) is a form of electromagnetic radiation discovered in 1965 that fills the entire universe. ... In physics, the photon (from Greek Ï†Ï‰Ï‚, phÅs, meaning light) is the quantum of the electromagnetic field; for instance, light. ... Baryogenesis is the generic designation for the physical processes that generate matter (more specifically, a class of fundamental particle called baryon) from an otherwise matter-empty state (such as it is generally believed to be the state of the Universe at its onset, the so-called Big Bang). ... In thermodynamics, a thermodynamic system is in thermodynamic equilibrium if its energy distribution equals a Maxwell-Boltzmann-distribution. ... Fig. ... For other uses, see Plasma. ... Recombination usually refers to the biological process of genetic recombination and meiosis, a genetic event that occurs during the formation of sperm and egg cells. ... In physics, Compton scattering or the Compton effect, is the decrease in energy (increase in wavelength) of an X-ray or gamma ray photon, when it interacts with matter. ... The Kelvin scale is a thermodynamic (absolute) temperature scale where absolute zeroâ€”the lowest possible temperature where nothing could be colder and no heat energy remains in a substanceâ€”is defined as zero kelvin (0 K). ... In physics, decoupling is the general phenomenon in which the interactions between some physical objects (such as elementary particles) disappear. ...

Because the early universe was in thermal equilibrium, the radiation from this time had a blackbody spectrum and freely streamed through space until today, becoming redshifted because of the Hubble expansion, reducing the high temperature of the blackbody spectrum. The radiation is thought to be observable at every point in the universe as coming from all directions. As the temperature decreases, the peak of the black body radiation curve moves to lower intensities and longer wavelengths. ...

In 1964, Arno Penzias and Robert Wilson accidentally discovered the cosmic background radiation while conducting diagnostic observations using a new microwave receiver owned by Bell Laboratories.^[3] Their discovery provided substantial confirmation of the general CMB predictions—the radiation was found to be isotropic and consistent with a blackbody spectrum of about 3 K—and it pitched the balance of opinion in favor of the Big Bang hypothesis. Penzias and Wilson were awarded the Nobel Prize for their discovery. Arno Allan Penzias (born April 26, American physicist. ... Robert Woodrow Wilson Robert Woodrow Wilson (born January 10, 1936) is an American physicist. ... Microwaves are electromagnetic waves with wavelengths longer than those of terahertz (THz) wavelengths, but relatively short for radio waves. ... Bell Telephone Laboratories or Bell Labs was originally the research and development arm of the United States Bell System, and was the premier corporate facility of its type, developing a range of revolutionary technologies from telephone switches to specialized coverings for telephone cables, to the transistor. ... Nobel Prize medal. ...

In 1989, NASA launched the Cosmic Background Explorer satellite (COBE), and the initial findings, released in 1990, were consistent with the Big Bang's predictions regarding the CMB. COBE found a residual temperature of 2.726 K and determined that the CMB was isotropic to about one part in 10⁵.^[21] During the 1990s, CMB anisotropies were further investigated by a large number of ground-based experiments and the universe was shown to be almost geometrically flat by measuring the typical angular size (the size on the sky) of the anisotropies. (See shape of the universe.) NASA Logo Listen to this article Â· (info) This audio file was created from the revision dated 2005-09-01, and does not reflect subsequent edits to the article. ... The Cosmic Background Explorer (COBE), also referred to as Explorer 66, was the first satellite built dedicated to cosmology. ... The shape of the Universe is an informal name for a subject of investigation within physical cosmology. ...

In early 2003, the results of the Wilkinson Microwave Anisotropy satellite (WMAP) were released, yielding what were at the time the most accurate values for some of the cosmological parameters. (See cosmic microwave background radiation experiments.) This satellite also disproved several specific cosmic inflation models, but the results were consistent with the inflation theory in general.^[22] Artist depiction of the WMAP satellite at the L2 point The Wilkinson Microwave Anisotropy Probe (WMAP) is a NASA satellite whose mission is to survey the sky to measure the temperature of the radiant heat left over from the Big Bang. ... In cosmology, the cosmic microwave background radiation (most often abbreviated CMB but occasionally CMBR, CBR or MBR, also referred as relic radiation) is a form of electromagnetic radiation discovered in 1965 that fills the entire universe. ... In physical cosmology, cosmic inflation is the idea that the nascent universe passed through a phase of exponential expansion that was driven by a negative-pressure vacuum energy density. ...

Abundance of primordial elements

Using the Big Bang model it is possible to calculate the concentration of helium-4, helium-3, deuterium and lithium-7 in the universe as ratios to the amount of ordinary hydrogen, H.^[23] All the abundances depend on a single parameter, the ratio of photons to baryons. The ratios predicted (by mass, not by number) are about 0.25 for ⁴He/H, about 10^-3 for ²H/H, about 10^-4 for ³He/H and about 10^-9 for ⁷Li/H. In cosmology, Big Bang nucleosynthesis (or primordial nucleosynthesis) refers to the production of nuclei other than H-1, the normal, light hydrogen, during the early phases of the universe, shortly after the Big Bang. ... General Name, Symbol, Number helium, He, 2 Chemical series noble gases Group, Period, Block 18, 1, s Appearance colorless Atomic mass 4. ... Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of planet Earth of approximately one atom in 6500 of hydrogen (~154 PPM). ... General Name, Symbol, Number lithium, Li, 3 Chemical series alkali metals Group, Period, Block 1, 2, s Appearance silvery white/grey Atomic mass 6. ... The word light is defined here as electromagnetic radiation of any wavelength; thus, X-rays, gamma rays, ultraviolet light, microwaves, radio waves, and visible light are all forms of light. ... In particle physics, the baryons are a family of subatomic particles including the proton and the neutron (collectively called nucleons), as well as a number of unstable, heavier particles (called hyperons). ...

The measured abundances all agree with those predicted from a single value of the baryon-to-photon ratio. The agreement is relatively poor for ⁷Li and ⁴He, the two elements for which the systematic uncertainties are least understood. This is considered strong evidence for the Big Bang, as the theory is the only known explanation for the relative abundances of light elements.^[24] Indeed there is no obvious reason outside of the Big Bang that, for example, the young universe (i.e., before star formation, as determined by studying matter essentially free of stellar nucleosynthesis products) should have more helium than deuterium or more deuterium than ³He, and in constant ratios, too. Systematic errors are biases in measurement which lead to measured values being systematically too high or too low. ... Cross section of a red giant showing nucleosynthesis and elements formed Stellar nucleosynthesis is the collective term for the nuclear reactions taking place in stars to build the nuclei of the heavier elements. ...

Galactic evolution and distribution

Detailed observations of the morphology and distribution of galaxies and quasars provide strong evidence for the Big Bang. A combination of observations and theory suggest that the first quasars and galaxies formed about a billion years after the Big Bang, and since then larger structures have been forming, such as galaxy clusters and superclusters. Populations of stars have been aging and evolving, so that distant galaxies (which are observed as they were in the early universe) appear very different from nearby galaxies (observed in a more recent state). Moreover, galaxies that formed relatively recently appear markedly different from galaxies formed at similar distances but shortly after the Big Bang. These observations are strong arguments against the steady-state model. Observations of star formation, galaxy and quasar distributions, and larger structures agree well with Big Bang simulations of the formation of structure in the universe and are helping to complete details of the theory.^[25] Astronomy and cosmology examine the universe to understand the large-scale structure of the cosmos. ... It has been suggested that this article or section be merged into Large-scale structure of the cosmos. ... In astrophysics, the questions of galaxy formation and evolution are: How, from a homogeneous universe, did we obtain the very heterogeneous one we live in? How did galaxies form? How do galaxies change over time? A spectacular head-on collision between two galaxies is seen in this NASA Hubble Space... Astronomers classify galaxies based on their overall shape (elliptical, spiral or barred spiral) and further by the specific properties of the individual galaxy (for example degree of ellipse, number of spirals or definition of bar). ... Astronomy and cosmology examine the universe to understand the large-scale structure of the cosmos. ... This view, taken with infrared light, is a false-color image of a quasar-starburst tandem with the most luminous starburst ever seen in such a combination. ... The galaxies of HCG 87, about four hundred million light-years distant. ... Superclusters are large groupings of smaller galaxy groups and clusters, and are among the largest structures of the cosmos. ... Star formation is the process by which dense parts of molecular clouds collapse into a ball of plasma to form a star. ...

Features, issues and problems

While currently there are very few researchers who doubt the Big Bang occurred, in the past the community was divided between supporters of the Big Bang and supporters of alternative cosmological models. Throughout the historical development of the subject, problems with the Big Bang theory were posed in the context of a scientific controversy regarding which model could best describe the cosmological observations (see history section above). With the overwhelming consensus in the community today supporting the Big Bang model, many of these problems are remembered as being mainly of historical interest; the solutions to them have been obtained either through modifications to the theory or as the result of better observations. Other issues, such as the cuspy halo problem and the dwarf galaxy problem of cold dark matter, are not considered to be fatal as they can be addressed through further refinements of the theory. A non-standard cosmology is a cosmological idea that contradicts the standard model of cosmology. ... Observational cosmology is the study of the structure, the evolution and the origin of the universe through observation, using instruments such as telescopes and cosmic ray detectors. ... Scientific consensus is the collective judgment, position, and opinion of scientists in a particular field of science at a particular time. ... The cuspy halo problem is one that arises from cosmological simulations that seem to indicate cold dark matter would form cuspy distributions in the most dense areas of the universe. ... The dwarf galaxy problem is one that arises from numerical cosmological simulations that predict the evolution of the distribution of matter in the universe. ... Cold dark matter (or CDM) is a refinement of the big bang theory that contains the additional assumption that most of the matter in the Universe consists of material which cannot be observed by its electromagnetic radiation and hence is dark while at the same time the particles making up...

The Big Bang model admits very exotic physical phenomena that include dark matter, dark energy, and cosmic inflation which rely on conditions and physics that have not yet been observed in terrestrial laboratory experiments. While explanations for such phenomena remain at the frontiers of inquiry in physics, independent observations of Big Bang nucleosynthesis, the cosmic microwave background, large scale structure and Type Ia supernovae strongly suggest the phenomena are important and real cosmological features of our universe. The gravitational effects of these features are understood observationally and theoretically but they have not yet been successfully incorporated into the Standard Model of particle physics. Though some aspects of the theory remain inadequately explained by fundamental physics, almost all cosmologists accept that the close agreement between Big Bang theory and observation have firmly established all the basic parts of the theory. Dark matter is a term used in astrophysics to refer to that component of the universe that is unaccounted for, unexplained or inconclusively explained, and whose existence at this time is only inferred. ... In physical cosmology, dark energy is a hypothetical form of energy that permeates all of space and has strong negative pressure. ... In physical cosmology, cosmic inflation is the idea that the nascent universe passed through a phase of exponential expansion that was driven by a negative-pressure vacuum energy density. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... In cosmology, Big Bang nucleosynthesis (or primordial nucleosynthesis) refers to the production of nuclei other than H-1, the normal, light hydrogen, during the early phases of the universe, shortly after the Big Bang. ... WMAP image of the CMB anisotropy,Cosmic microwave background radiation(June 2003) The cosmic microwave background radiation (CMB) is a form of electromagnetic radiation that fills the whole of the universe. ... Astronomy and cosmology examine the universe to understand the large-scale structure of the cosmos. ... Multiwavelength X-ray image of the remnant of Keplers Supernova, SN 1604. ... Gravity is a force of attraction that acts between bodies that have mass. ... The Standard Model of Fundamental Particles and Interactions For the Standard Model in Cryptography, see Standard Model (cryptography). ... Thousands of particles explode from the collision point of two relativistic (100 GeV per nucleon) gold ions in the STAR detector of the Relativistic Heavy Ion Collider. ...

Horizon problem

The horizon problem results from the premise that information cannot travel faster than light, and hence two regions of space which are separated by a greater distance than the speed of light multiplied by the age of the universe cannot be in causal contact.^[23] The observed isotropy of the cosmic microwave background (CMB) is problematic in this regard, because the horizon size at that time corresponds to a size that is about 2 degrees on the sky. If the universe has had the same expansion history since the Planck epoch, there is no mechanism to cause these regions to have the same temperature. When we look at the CMB it comes from 15 billion light years away. ... For other uses, see Faster than the speed of light (disambiguation). ... Although causality, the relationship between causes and effects, is often examined in the fields of philosophy, computer science, and statistics, it has a place in the study of physics as well. ... WMAP image of the CMB anisotropy,Cosmic microwave background radiation(June 2003) The cosmic microwave background radiation (CMB) is a form of electromagnetic radiation that fills the whole of the universe. ... It has been suggested that this article or section be merged into Observable universe. ... Named after Max Planck, in cosmology the Planck epoch (or Planck Era) is the earliest period of time in the history of the universe, from zero to 10-43 seconds (one Planck time), during which all four fundamental forces were unified and elementary particles did not yet exist. ...

A resolution to this apparent inconsistency is offered by inflationary theory in which a homogeneous and isotropic scalar energy field dominates the universe at a time 10^-35 seconds after the Planck epoch. During inflation, the universe undergoes exponential expansion, and regions in causal contact expand so as to be beyond each other's horizons. Heisenberg's uncertainty principle predicts that during the inflationary phase there would be quantum thermal fluctuations, which would be magnified to cosmic scale. These fluctuations serve as the seeds of all current structure in the universe. After inflation, the universe expands according to Hubble's law, and regions that were out of causal contact come back into the horizon. This explains the observed isotropy of the CMB. Inflation predicts that the primordial fluctuations are nearly scale invariant and Gaussian which has been accurately confirmed by measurements of the CMB. Inflation is the idea—first proposed by Alan Guth (1981)—that the nascent universe passed through a phase of exponential expansion (the inflationary epoch) that was driven by a negative pressure vacuum energy density. ... In quantum physics, the Heisenberg uncertainty principle, sometimes called the Heisenberg indeterminacy principle, expresses a limitation on accuracy of (nearly) simultaneous measurement of observables such as the position and the momentum of a particle. ... Primordial fluctuations are density variations in the early universe which are considered the seeds of all structure in the universe. ... Hubbles law is the statement in physical cosmology that the redshift in light coming from distant galaxies is proportional to their distance. ... Primordial fluctuations are density variations in the early universe which are considered the seeds of all structure in the universe. ... In physics, scale invariance is the feature of physical objects of laws that do not change if the space is magnified, i. ... The normal distribution, also called Gaussian distribution (named after Carl Friedrich Gauss, a German mathematician, although Gauss was not the first to work with it), is a probability distribution of great importance in many fields. ...

Flatness problem

The flatness problem is an observational problem that results from considerations of the geometry associated with a Friedmann-Lemaître-Robertson-Walker metric.^[23] In general, the universe can have three different kinds of geometries: hyperbolic geometry, Euclidean geometry, or elliptic geometry. The geometry is determined by the total energy density of the universe (as measured by means of the stress-energy tensor): hyperbolic results from a density less than the critical density, elliptic from a density greater than the critical density, and Euclidean from exactly the critical density. The universe is required to be within one part in 10¹⁵ of the critical density in its earliest stages. Any greater deviation would have caused either a Heat Death or a Big Crunch, and the universe would not exist as it does today. Image File history File links End_of_universe. ... Image File history File links End_of_universe. ... The shape of the Universe is an informal name for a subject of investigation within physical cosmology. ... The Friedmann equations relate various cosmological parameters within the context of general relativity. ... The shape of the Universe is an informal name for a subject of investigation within physical cosmology. ... The shape of the Universe is an informal name for a subject of investigation within physical cosmology. ... The shape of the Universe is an informal name for a subject of investigation within physical cosmology. ... The flatness problem is a cosmological problem with the Big Bang theory, which is solved by hypothesising an inflationary universe. ... The shape of the Universe is an informal name for a subject of investigation within physical cosmology. ... The Friedmann-LemaÃ®tre-Robertson-Walker (FLRW) metric describes a homogeneous, isotropic expanding/contracting universe. ... Lines through a given point P and hyperparallel to line l. ... Euclid Euclidean geometry is a mathematical system attributed to the Greek mathematician Euclid of Alexandria. ... Elliptic geometry (sometimes known as Riemannian geometry) is a non-Euclidean geometry, in which, given a line L and a point p outside L, there exists no line parallel to L passing through p. ... This article is in need of attention from an expert on the subject. ... In cosmology, the Big Crunch is a hypothesis that states the universe will stop expanding and start to collapse upon itself; a counterpart to the Big Bang. ... The heat death is a possible final state of the universe, in which it has reached maximum entropy. ... In physical cosmology, the Big Crunch is a hypothesized collapse of the universe upon itself after its expansion eventually stops â€” a counterpart to the Big Bang. ...

A possible resolution to this problem is again offered by inflationary theory. During the inflationary period, spacetime expanded to such an extent that any residual curvature associated with it would have been smoothed out to a high degree of precision. Thus, it is believed that inflation drove the universe to be very nearly spatially flat. Inflation is the idea—first proposed by Alan Guth (1981)—that the nascent universe passed through a phase of exponential expansion (the inflationary epoch) that was driven by a negative pressure vacuum energy density. ... Curvature refers to a number of loosely related concepts in different areas of geometry. ...

Magnetic monopoles

The magnetic monopole objection was raised in the late 1970s. Grand unification theories predicted point defects in space that would manifest as magnetic monopoles with a density much higher than was consistent with observations, given that searches have never found any monopoles. This problem is also resolvable by cosmic inflation, which removes all point defects from the observable universe in the same way that it drives the geometry to flatness.^[23] In physics, a magnetic monopole is a hypothetical particle that may be loosely described as a magnet with only one pole (see electromagnetic theory for more on magnetic poles). ... It has been suggested that this article or section be merged into Unified field theory. ... In cosmology, a topological defect is a (often) stable configuration of matter predicted by some theories to form at phase transitions in the very early universe. ... In physics, a magnetic monopole is a hypothetical particle that may be loosely described as a magnet with only one pole (see electromagnetic theory for more on magnetic poles). ... In physical cosmology, cosmic inflation is the idea that the nascent universe passed through a phase of exponential expansion that was driven by a negative-pressure vacuum energy density. ...

Baryon asymmetry

It is not yet understood why the universe has more matter than antimatter.^[23] It is generally assumed that when the universe was young and very hot, it was in statistical equilibrium and contained equal numbers of baryons and anti-baryons. However, observations suggest that the universe, including its most distant parts, is made almost entirely of matter. An unknown process called baryogenesis created the asymmetry. For baryogenesis to occur, the Sakharov conditions, which were laid out by Andrei Sakharov, must be satisfied. They require that baryon number be not conserved, that C-symmetry and CP-symmetry be violated, and that the universe depart from thermodynamic equilibrium.^[26] All these conditions occur in the Standard Model, but the effect is not strong enough to explain the present baryon asymmetry.^[27] Experiments taking place at CERN near Geneva seek to trap enough anti-hydrogen to compare its spectrum with hydrogen. Any difference would be evidence of a CPT symmetry violation and therefore a Lorentz violation. This article or section does not cite its references or sources. ... In particle physics, antimatter extends the concept of the antiparticle to matter, wherein if a particle and its antiparticle come into contact with each other, the two annihilate â€”that is, they may both be converted into other particles with equal energy in accordance with Einsteins equation E = mc2. ... In particle physics, the baryons are a family of subatomic particles including the proton and the neutron (collectively called nucleons), as well as a number of unstable, heavier particles (called hyperons). ... Baryogenesis is the generic designation for the physical processes that generate matter (more specifically, a class of fundamental particle called baryon) from an otherwise matter-empty state (such as it is generally believed to be the state of the Universe at its onset, the so-called Big Bang). ... Andrei Sakharov, 1943 Dr. Andrei Dmitrievich Sakharov (Russian: , May 21, 1921 â€“ December 14, 1989), was an eminent Soviet nuclear physicist, dissident and human rights activist. ... In particle physics, the baryon number is an approximate conserved quantum number. ... C-symmetry means the symmetry of physical laws over a charge-inversion transformation. ... CP-symmetry is a symmetry obtained by a combination of the C-symmetry and the P-symmetry. ... In thermodynamics, a thermodynamic system is said to be in thermodynamic equilibrium when it is in thermal equilibrium, mechanical equilibrium, and chemical equilibrium. ... The Standard Model of Fundamental Particles and Interactions For the Standard Model in Cryptography, see Standard Model (cryptography). ... CERN logo The Organisation EuropÃ©enne pour la Recherche NuclÃ©aire (English: European Organization for Nuclear Research), commonly known as CERN, pronounced (or in French), is the worlds largest particle physics laboratory, situated just west of Geneva on the border between France and Switzerland. ... Antihydrogen is the antimatter counterpart of hydrogen. ... CPT-symmetry is a fundamental symmetry of physical laws under transformations that involve the inversions of charge, parity and time simultaneously. ... Lorentz violation refers to theories which are approximately relativistic when it comes to experiments that have actually been performed (and there are quite a number of such experimental tests) but yet contain tiny or hidden Lorentz violating corrections. ...

Globular cluster age

In the mid-1990s, observations of globular clusters appeared to be inconsistent with the Big Bang. Computer simulations that matched the observations of the stellar populations of globular clusters suggested that they were about 15 billion years old, which conflicted with the 13.7-billion-year age of the universe. This issue was generally resolved in the late 1990s when new computer simulations, which included the effects of mass loss due to stellar winds, indicated a much younger age for globular clusters.^[28] There still remain some questions as to how accurately the ages of the clusters are measured, but it is clear that these objects are some of the oldest in the universe. The Globular Cluster M80 in the constellation Scorpius is located about 28,000 light years from the Sun and contains hundreds of thousands of stars. ... This article is about the astronomical object. ... A solar wind is a stream of particles (mostly high-energy protons ~ 500 keV) which are ejected from the upper atmosphere of a star (in the case of a star other than the Earths Sun, it may be called a stellar wind instead). ...

Dark matter

During the 1970s and 1980s, various observations (notably of galactic rotation curves) showed that there was not sufficient visible matter in the universe to account for the apparent strength of gravitational forces within and between galaxies. This led to the idea that up to 90% of the matter in the universe is not normal or baryonic matter but rather dark matter. In addition, assuming that the universe was mostly normal matter led to predictions that were strongly inconsistent with observations. In particular, the universe is far less lumpy and contains far less deuterium than can be accounted for without dark matter. While dark matter was initially controversial, it is now a widely accepted part of standard cosmology due to observations of the anisotropies in the CMB, galaxy cluster velocity dispersions, large-scale structure distributions, gravitational lensing studies, and x-ray measurements from galaxy clusters. In August 2006, dark matter was definitively observed^[29]^[30] through measurements of colliding galaxies in the Bullet Cluster. This and other detections of dark matter are only sensitive to its gravitational signature; no dark matter particles have yet been observed in laboratories. However, there are many particle physics candidates for dark matter, and several projects to detect them directly are underway. Dark matter is a term used in astrophysics to refer to that component of the universe that is unaccounted for, unexplained or inconclusively explained, and whose existence at this time is only inferred. ... Image File history File links Cosmological_composition. ... Image File history File links Cosmological_composition. ... A pie chart is a circular chart divided into sectors, illustrating relative magnitudes or frequencies. ... A pie chart indicating the proportional composition of different energy-density components of the universe. ... Dark matter is a term used in astrophysics to refer to that component of the universe that is unaccounted for, unexplained or inconclusively explained, and whose existence at this time is only inferred. ... In physical cosmology, dark energy is a hypothetical form of energy that permeates all of space and has strong negative pressure. ... The galaxy rotation problem is the discrepancy between the observed rotation speeds of matter in the disk portions of spiral galaxies and the predictions of Newtonian dynamics considering the luminous mass. ... In particle physics, the baryons are a family of subatomic particles including the proton and the neutron (collectively called nucleons), as well as a number of unstable, heavier particles (called hyperons). ... Dark matter is a term used in astrophysics to refer to that component of the universe that is unaccounted for, unexplained or inconclusively explained, and whose existence at this time is only inferred. ... Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of planet Earth of approximately one atom in 6500 of hydrogen (~154 PPM). ... The galaxies of HCG 87, about four hundred million light-years distant. ... A gravitational lens is formed when the light from a very distant, bright source (such as a quasar) is bent around a massive object (such as a massive galaxy) between the source object and the observer. ... In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz... The Bullet cluster (1E 0657-56) consists of two colliding clusters of galaxies. ... Thousands of particles explode from the collision point of two relativistic (100 GeV per nucleon) gold ions in the STAR detector of the Relativistic Heavy Ion Collider. ...

Dark energy

In the 1990s, detailed measurements of the mass density of the universe revealed a value that was 30% that of the critical density.^[9] Since the universe is very nearly spatially flat, as is indicated by measurements of the cosmic microwave background, about 70% of the energy density of the universe was left unaccounted for. This mystery now appears to be connected to another one: Independent measurements of Type Ia supernovae have revealed that the expansion of the universe is undergoing a non-linear acceleration. To explain this acceleration, general relativity requires that much of the universe consist of an energy component with large negative pressure. This dark energy is now thought to make up the missing 70%. Its nature remains one of the great mysteries of the Big Bang. Possible candidates include a scalar cosmological constant and quintessence. Observations to help understand this are ongoing. Results from WMAP in 2006 indicate that the universe is 74% dark energy, 22% dark matter, and 4% regular matter (see external link). In physical cosmology, dark energy is a hypothetical form of energy that permeates all of space and has strong negative pressure. ... Density, or volumic mass (ISO 31), is a measure of mass per volume. ... In cosmology, the Big Crunch is a hypothesis that states the universe will stop expanding and start to collapse upon itself; a counterpart to the Big Bang. ... WMAP image of the CMB anisotropy,Cosmic microwave background radiation(June 2003) The cosmic microwave background radiation (CMB) is a form of electromagnetic radiation that fills the whole of the universe. ... Remnant of Keplers Supernova, SN 1604. ... The Accelerating universe is the idea that our universe is undergoing accelerated expansion: distant objects are receding from our galaxy with speeds that increase over time. ... General relativity (GR) is the geometrical theory of gravitation published by Albert Einstein in 1915/16. ... In cosmology, the equation of state of a perfect fluid is characterized by a dimensionless number w, equal to the ratio of its pressure p to its energy density ρ: . It is closely related to the thermodynamic equation of state and ideal gas law. ... In physical cosmology, dark energy is a hypothetical form of energy that permeates all of space and has strong negative pressure. ... The cosmological constant (usually denoted by the Greek capital letter lambda: Î›) was proposed by Albert Einstein as part of his theory of general relativity to achieve a stationary universe. ... In physics, quintessence is a hypothetical form of dark energy postulated as an explanation of observations of an accelerating universe. ...

The future according to the Big Bang theory

Before observations of dark energy, cosmologists considered two scenarios for the future of the universe. If the mass density of the universe is above the critical density, then the universe would reach a maximum size and then begin to collapse. It would become denser and hotter again, ending with a state that was similar to that in which it started—a Big Crunch. Alternatively, if the density in the universe is equal to or below the critical density, the expansion would slow down, but never stop. Star formation would cease as the universe grows less dense. The average temperature of the universe would asymptotically approach absolute zero—a Big Freeze. Black holes would evaporate. The entropy of the universe would increase to the point where no organized form of energy could be extracted from it, a scenario known as heat death. Moreover, if proton decay exists, then hydrogen, the predominant form of baryonic matter in the universe today, would disappear, leaving only radiation. The ultimate fate of our universe is a topic in physical cosmology. ... Density, or volumic mass (ISO 31), is a measure of mass per volume. ... In cosmology, the Big Crunch is a hypothesis that states the universe will stop expanding and start to collapse upon itself; a counterpart to the Big Bang. ... In physical cosmology, the Big Crunch is a hypothesized collapse of the universe upon itself after its expansion eventually stops â€” a counterpart to the Big Bang. ... Absolute zero is the lowest possible temperature where nothing could be colder and no heat energy remains in a substance. ... The Big Freeze is a scenario in which the universe simply becomes too cold to sustain life due to continued expansion. ... A black hole is an object predicted by general relativity,[1] with a gravitational field so powerful that even electromagnetic radiation (including light itself) cannot escape its pull. ... In physics, Hawking radiation is thermal radiation thought to be emitted by black holes due to quantum effects. ... Ice melting - classic example of entropy increasing[1] described in 1862 by Rudolf Clausius as an increase in the disgregation of the molecules of the body of ice. ... The heat death is a possible final state of the universe, in which it has reached maximum entropy. ... The decay of a proton, a baryon, into non-baryonic matter, does not occur perturbatively in the Standard Model. ...

Modern observations of accelerated expansion imply that more and more of the currently visible universe will pass beyond our event horizon and out of contact with us. The eventual result is not known. The ΛCDM model of the universe contains dark energy in the form of a cosmological constant. This theory suggests that only gravitationally bound systems, such as galaxies, would remain together, and they too would be subject to heat death, as the universe cools and expands. Other explanations of dark energy — so-called phantom energy theories — suggest that ultimately galaxy clusters and eventually galaxies themselves will be torn apart by the ever-increasing expansion in a so-called Big Rip. The Accelerating universe is the idea that our universe is undergoing accelerated expansion: distant objects are receding from our galaxy with speeds that increase over time. ... This article or section is in need of attention from an expert on the subject. ... A pie chart indicating the proportional composition of different energy-density components of the universe. ... In physical cosmology, dark energy is a hypothetical form of energy that permeates all of space and has strong negative pressure. ... The cosmological constant (usually denoted by the Greek capital letter lambda: Î›) was proposed by Albert Einstein as part of his theory of general relativity to achieve a stationary universe. ... The heat death is a possible final state of the universe, in which it has reached maximum entropy. ... Phantom energy is a hypothetical form of dark energy with equation of state . ... The galaxies of HCG 87, about four hundred million light-years distant. ... This article is about a celestial body. ... The Big Rip is a cosmological hypothesis about the ultimate fate of the Universe, in which the elements of the universe, from galaxies to atoms, are progressively torn apart by the expansion of the universe. ...

Speculative physics beyond the Big Bang

While the Big Bang model is well established in cosmology, it is likely to be refined in the future. Little is known about the earliest universe, when inflation is hypothesized to have occurred. There may also be parts of the universe well beyond what can be observed in principle. In the case of inflation this is required: exponential expansion has pushed large regions of space beyond our observable horizon. It may be possible to deduce what happened when we better understand physics at very high energy scales. Speculations about this often involve theories of quantum gravitation. Image File history File links Download high resolution version (3000x2159, 1051 KB) Summary NASA WMAP science team Licensing File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Download high resolution version (3000x2159, 1051 KB) Summary NASA WMAP science team Licensing File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... In mathematics, the metric tensor is a symmetric tensor field of rank 2 that is used to measure distance in a space. ... Artist depiction of the WMAP satellite at the L2 point The Wilkinson Microwave Anisotropy Probe (WMAP) is a NASA satellite whose mission is to survey the sky to measure the temperature of the radiant heat left over from the Big Bang. ... Image File history File links Download high resolution version (3000x2159, 1051 KB) Summary NASA WMAP science team Licensing File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... This article or section does not cite its references or sources. ...

Some of these scenarios are qualitatively compatible with one another. Each entails untested hypotheses. In theoretical physics, the Hartle-Hawking state, named after James Hartle and Stephen Hawking, is a hypothetical vector in the Hilbert space of a theory of quantum gravity that describes the wave function of the Universe. ... Brane cosmology is a protoscience motivated by, but not rigorously derived from, superstring theory and M-theory. ... Interaction in the subatomic world: world lines of pointlike particles in the Standard Model or a world sheet swept up by closed strings in string theory String theory is a model of fundamental physics whose building blocks are one-dimensional extended objects (strings) rather than the zero-dimensional points (particles... The ekpyrotic universe or ekpyrotic scenario is a cosmological theory of the origin of the universe. ... The cyclic model is a brane cosmology model of the creation of the universe, derived from the earlier ekpyrotic model. ... The theory created by Andrei Linde that states that our universe could have come from nothing more than hundred-thousandth of a gram of matter. ...

Philosophical and religious interpretations

The Big Bang, a scientific theory, is not based on any religion. Some people have found similarities, however, that they believe have both theological and philosophical implications, since some religious interpretations and world views conflict with the Big Bang origin of the universe. A world view, (or worldview) is a term calqued from the German word Weltanschauung (pronounced //) meaning a look onto the world. It implies a concept fundamental to German philosophy and epistemology and refers to a wide world perception. ...

Some interpretations of the Big Bang theory go beyond science, and some purport to explain the cause of the Big Bang itself (first cause). These views have been criticized by some naturalist philosophers as being modern creation myths. Some people believe that the Big Bang theory is inconsistent with traditional views of creation such as that in Genesis, for example, while others, like astronomer Hugh Ross, believe that the Big Bang theory lends support to the idea of creation ex nihilo.^[31] Categories: Wikipedia cleanup | Stub | Philosophy of science | Religious Philosophy | Theology ... Naturalism is any of several philosophical stances, typically those descended from materialism and pragmatism, that reject the validity of explanations or theories making use of entities inaccessible to natural science. ... Creation beliefs and stories describe how the universe, the Earth, life, and/or humanity came into being. ... Genesis (Hebrew: , Greek: Î“ÎÎ½ÎµÏƒÎ¹Ï‚, having the meanings of birth, creation, cause, beginning, source and origin) is the first book of the Torah, the first book of the Tanakh and also the first book of the Christian Old Testament. ... Hugh Ross Hugh N. Ross (born 1945) is a Canadian-born Old Earth Creationist. ... Ex nihilo is a Latin term meaning out of nothing. It is often used in conjunction with the term creation, as in creatio ex nihilo, meaning creation out of nothing. Due to the nature of this, the term is often used in philosophical or creationistic arguments, as a number of...

The following is a list of various religious interpretations of the Big Bang theory:

Christianity is a monotheistic[1] religion centered on Jesus of Nazareth and his life, death, resurrection, and teachings as presented in the New Testament. ... The word Jew ( Hebrew: יהודי) is used in a wide number of ways, but generally refers to a follower of the Jewish faith, a child of a Jewish mother, or someone of Jewish descent with a connection to Jewish culture or ethnicity and often a combination... Pope Pius XII (Latin: ), born Eugenio Maria Giuseppe Giovanni Pacelli (March 2, 1876 â€“ October 9, 1958), reigned as the 260th pope, the head of the Roman Catholic Church, and sovereign of Vatican City State from March 2, 1939 until his death. ... The Roman Catholic Church or Catholic Church (see terminology below) is the Christian Church in full communion with the Bishop of Rome, currently Pope Benedict XVI. It traces its origins to the original Christian community founded by Jesus of Nazareth, with its traditions first established by the Twelve Apostles and... Creation according to Genesis refers to the description of the creation of the heavens and the earth by God, as described in Genesis, the first book of the Bible. ... Judaism is the religion of the Jewish people. ... This article is about traditional Kabbalah (Jewish mysticism). ... Islam (Arabic: ) is a monotheistic religion based upon the teachings of Muhammad, a 7th century Arab religious and political figure. ... The QurÄn [1] (Arabic: â€Ž, literally the recitation; also called The Noble QurÄn; also transliterated as Quran, Koran, and Al-Quran), is the central religious text of Islam. ... In physical cosmology, the Big Crunch is a hypothesized collapse of the universe upon itself after its expansion eventually stops â€” a counterpart to the Big Bang. ... The Oscillatory Universe is the hypothesis, due to Richard Tolman, that the universe undergoes an infinite series of oscillations, each beginning with a big bang and ending with a big crunch. ... Theism is the belief in the existence of one or more Gods or deities. ... Hinduism (Sanskrit: eternal law; in several modern Indian languages[1] also known as ), is a religion that originated on the Indian subcontinent. ... Maha-Vishnu depicted as resting on the causal ocean, with countless universes emanating from his skin pores. ... The Bhagavata Purana (sometimes rendered as Bhagavatha Purana), also known as the Srimad Bhagavatam, written c. ... Vishnu (IAST , Devanagari , with honorific Shri Vishnu; , ), (also frequently referred to as Narayana) is the most popularly worshipped form of God in Hinduism [1]. Within the Vaishnava tradition he is viewed as the Ultimate Reality or Supreme God (similarly to Shiva within Shaivism). ... Prakrti or Prakriti (from Sanskrit language) is, according to samkhya philosophy the basic matter of which the universe consists. ... Buddhism Buddhism is a dharmic, non-theistic religion, a philosophy, and a system of psychology. ... This article is about the religion Zen. ... The oscillatory universe is the hypothesis, attributable to Richard Tolman, that the universe undergoes an infinite series of oscillations, each beginning with a big bang and ending with a big crunch. ...

Notes

^ R. A. Alpher, H. Bethe, G. Gamow, "The Origin of Chemical Elements,"Physical Review 73 (1948), 803.
^ G. Gamow, Nature 162 (1948), 680.
^ ^a ^b A. A. Penzias and R. W. Wilson, "A Measurement of Excess Antenna Temperature at 4080 Mc/s," Astrophysical Journal 142 (1965), 419.
^ R. H. Dicke, P. J. E. Peebles, P. G. Roll and D. T. Wilkinson, "Cosmic Black-Body Radiation," Astrophysical Journal 142 (1965), 414.
^ V. Slipher, paper presented to the American Astronomical Society, (1915).
^ G. Lemaître (1927). "Un Univers homogène de masse constante et de rayon croissant rendant compte de la vitesse radiale des nébuleuses extragalactiques". Annals of the Scientific Society of Brussels 47A: 41. Translated in: (1931) "A homogeneous universe of constant mass and growing radius accounting for the radial velocity of extragalactic nebulae". Monthly Notices of the Royal Astronomical Society 91: 483–490.. The "primeval atom" was introduced here: G. Lemaître, Nature 128 (1931) suppl.: 704.
^ Edwin Hubble (1929). "A relation between distance and radial velocity among extra-galactic nebulae". Proc. Nat. Acad. Sci. 15: 168–173.
^ E. Christianson. Edwin Hubble: Mariner of the Nebulae.
^ ^a ^b P. J. E. Peebles and Bharat Ratra (2003). "The cosmological constant and dark energy". Reviews of Modern Physics 75: 559–606.
^ F. Hoyle, '"A New Model for the Expanding universe", Monthly Notices of the Royal Astronomical Society, 108 (1948), 372.
^ The book in question can be downloaded here: [1]
^ E. A. Milne (1935). Relativity, Gravitation and World Structure. Oxford University Press.
^ R. C. Tolman (1934). Relativity, Thermodynamics, and Cosmology. Oxford: Clarendon Press. LCCN 340-32023. Reissued (1987) New York: Dover ISBN 0-486-65383-8.
^ Zwicky, F. 1929. On the Red Shift of Spectral Lines through Interstellar Space. PNAS 15:773-779. Abstract (ADS) Full article (PDF)
^ S. W. Hawking and G. F. R. Ellis, The large-scale structure of space-time (Cambridge, 1973).
^ A. V. Ivanchik, et al. "The fine-structure constant: a new observational limit on its cosmological variation and some theoretical consequences", Astronomy and Astrophysics 343 (1999) 439.
^ J. Goodman Physics Review D, 52 (1995) 1821.
^ Caltech Submillimeter Observatory has a program underway for measuring detail observations of the CMB to look for Sunyaev-Zel'dovich Effect correlations. [2]
^ Hubble, Edwin, "A Relation between Distance and Radial Velocity among Extra-Galactic Nebulae" (1929) Proceedings of the National Academy of Sciences of the United States of America, Volume 15, Issue 3, pp. 168-173 (Full article, PDF)
^ D. N. Spergel, et al. "First-year Wilkinson Microwave Anisotropy Probe (WMAP) observations: Determination of cosmological parameters", Astrophysical Journal Supplement Series, 148 (2003) 175.
^ N.W. Boggess, et al. "The COBE Mission: Its Design and Performance Two Years after the launch," Astrophysical Journal, 397 (1992), 420.
^ D. N. Spergel et al. (WMAP collaboration) (March 2006). "Wilkinson Microwave Anisotropy Probe (WMAP) three year results: implications for cosmology".
^ ^a ^b ^c ^d ^e Kolb, Edward; Michael Turner (1988). The Early Universe. Addison-Wesley. ISBN 0-201-11604-9.
^ Steigman, Gary, Primordial Nucleosynthesis: Successes And Challenges arXiv:astro-ph/0511534.
^ E. Bertschinger (2001). "Cosmological perturbation theory and structure formation". Edmund Bertschinger (1998). "Simulations of structure formation in the universe". Annual Review of Astronomy and Astrophysics 36: 599–654.
^ A. D. Sakharov, "Violation of CP invariance, C asymmetry and baryon asymmetry of the universe," Pisma Zh. Eksp. Teor. Fiz. 5, 32 (1967), translated in JETP Lett. 5, 24 (1967).
^ See "Antimatter and the Big Bang" - A research paper about the big bang's antimatter problem. This paper won the grand prize in the Answers in Genesis War of the Worldviews Research Paper Challenge 2006.
^ A. A. Navabi and N. Riazi, "Is the Age Problem Resolved?" Journal of Astrophysics and Astronomy 24 (2003), 3.
^ A direct empirical proof of the existence of dark matter. Arxiv.
^ Dark Matter Observed. SLAC Today.
^ Hugh Ross, "Putting the Big Bang to the Test" Accessed Sept. 19, 2006
^ The Kabbalah Centre, "Adam and Atom," Kabbalah On.., Accessed November 12, 2006
^ There are more prosaic translations of this verse which do not suggest an expanding universe including "And the heaven, We raised it high with power, and We are Makers of the vast extent." and "With power and skill did We construct the Firmament: for it is We Who create the vastness of space." However, Islamic scholars generally consider only the original Arabic text to be authoritative, and many state that the original Arabic text indeed indicates an expanding universe.

Robert Henry Dicke (May 6, 1916 â€“ March 4, 1997) was an American experimental physicist, who made important contributions to the fields of astrophysics, atomic physics, cosmology and gravity. ... David Todd Wilkinson (13 May 1935 â€“ 5 September 2002) was a world-renowned pioneer in the field of cosmology, specializing in the study of the cosmic microwave background radiation (CMB) left over from the Big Bang. ... The American Astronomical Society (AAS) is a US society of professional astronomers and other interested individuals, headquartered in Washington, DC. The main aim of the AAS is provide a political voice for its members and organise their lobbying. ... arXiv (pronounced archive, as if the X were the Greek letter Ï‡) is an archive for electronic preprints of scientific papers in the fields of physics, mathematics, computer science and biology which can be accessed via the internet. ... AiGs logo Answers in Genesis (AiG) is a non-profit Christian apologetics ministry with a particular focus on Young Earth Creationism, and a literal or plain[1] interpretation of the first chapters of the Book of Genesis. ... arXiv (pronounced archive, as if the X were the Greek letter Ï‡) is an archive for electronic preprints of scientific papers in the fields of physics, mathematics, computer science and biology which can be accessed via the internet. ... The Stanford Linear Accelerator Center (SLAC) is a U.S. national laboratory operated by Stanford University for the U.S. Department of Energy. ... Translations of the QurÃ¡n are versions of the holy book of Islam in languages other than Arabic. ...

External links and references

Big Bang overviews

Cosmic Journey: A History of Scientific Cosmology from the American Institute of Physics
Cosmology at the Open Directory Project
PBS.org, "From the Big Bang to the End of the universe. The Mysteries of Deep Space Timeline"
"Welcome to the History of the universe". Penny Press Ltd.
Cambridge University Cosmology, "The Hot Big Bang Model". Includes a discussion of the problems with the Big Bang.
Smithsonian Institution, "UNIVERSE! - The Big Bang and what came before".
D'Agnese, Joseph, "The last Big Bang man left standing, physicist Ralph Alpher devised Big Bang Theory of universe". Discover, July 1999.
Felder, Gary, "The Expanding universe".
LaRocco, Chris and Blair Rothstein, "THE BIG BANG: It sure was BIG!!".
Mather, John C., and John Boslough 1996, The very first light: the true inside story of the scientific journey back to the dawn of the universe. ISBN 0-465-01575-1 p.300
Shestople, Paul, ""Big Bang Primer".
Singh, Simon, Big Bang: The most important scientific discovery of all time and why you need to know about it, Fourth Estate (2004). A historical review of the Big Bang. Sample text and reviews can be found at [4].
Wright, Edward L., "Brief History of the universe".
Feuerbacher, Björn and Ryan Scranton (2006). "Evidence for the Big Bang", FAQ at talkorigins.org.
"Proof of Big Bang Seen by Space Probe, Scientists Say" — National Geographic News
The Sabanci University School of Languages Podcasts: Origin of Elements by Alpay Taralp.
Scientific American Magazine (March 2005 Issue) Misconceptions about the Big Bang
Scientific American Magazine (May 2006 Issue) The First Few Microseconds
R. A. Alpher and R. Herman, "Reflections on early work on 'big bang' cosmology" Physics Today Aug 1988 24–34. A review article.
The Big Bang and Cosmic Microwave Background and More Evidence for the Big Bang, episodes of the Astronomy Cast podcast dealing with the Big Bang.

Cosmology, as a branch of astrophysics, is the study of the large-scale structure of the universe and is concerned with fundamental questions about its formation and evolution. ... The Open Directory Project (ODP), also known as dmoz (from directory. ... PBS re-directs here; for alternate uses see PBS (disambiguation) PBS logo The Public Broadcasting Service (PBS) is a non-profit public broadcasting television service with 349 member TV stations in the United States. ... The University of Cambridge, located in Cambridge, England, is the second-oldest university in the English-speaking world, with a reputation as one of the worlds most prestigious universities. ... The Smithsonian Institution Building or Castle on the National Mall serves as the Institutions headquarters. ... Big Bang: The most important scientific discovery of all time and why you need to know about it is a book written by Simon Singh and published in 2004 by Fourth Estate. ... An orange square with waves was introduced by Mozilla Firefox to indicate that an RSS feed is present on a webpage. ...

Contents

History

Overview

Theoretical underpinnings

Observational evidence

Hubble's law expansion

Cosmic microwave background radiation

Abundance of primordial elements

Galactic evolution and distribution

Features, issues and problems

Horizon problem

Flatness problem

Magnetic monopoles

Baryon asymmetry

Globular cluster age

Dark matter

Dark energy

The future according to the Big Bang theory

Speculative physics beyond the Big Bang

Philosophical and religious interpretations

Notes

External links and references

Big Bang overviews

Religion and philosophy

Research articles

Contents

History GA_googleFillSlot("encyclopedia_square");

Overview

Theoretical underpinnings

Observational evidence

Hubble's law expansion

Cosmic microwave background radiation

Abundance of primordial elements

Galactic evolution and distribution

Features, issues and problems

Horizon problem

Flatness problem

Magnetic monopoles

Baryon asymmetry

Globular cluster age

Dark matter

Dark energy

The future according to the Big Bang theory

Speculative physics beyond the Big Bang

Philosophical and religious interpretations

Notes

External links and references

Big Bang overviews

Religion and philosophy

Research articles

History