edit 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. It is believed to be responsible for the formation of hydrogen (H-1 or H), its isotope deuterium (H-2 or D), the helium isotopes He-3 and He-4, and the lithium isotope Li-7. Big Bang nucleosynthesis - Sequence of BBN. Big Bang nucleosynthesis begins about one ...

Including:

Big Bang nucleosynthesis - Sequence of BBN
Big Bang nucleosynthesis - History of Big Bang nucleosynthesis Big Bang nucleosynthesis - Heavy elements Big Bang nucleosynthesis - Helium-4 Big Bang nucleosynthesis - Deuterium
Big Bang nucleosynthesis - Status and Implications of BBN Big Bang nucleosynthesis - Non-standard BBN

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Big Bang nucleosynthesis, Big Bang nucleosynthesis - Sequence of BBN, Big Bang nucleosynthesis - History of Big Bang nucleosynthesis, Big Bang nucleosynthesis - Heavy elements, Big Bang nucleosynthesis - Helium-4, Big Bang nucleosynthesis - Deuterium, Big Bang nucleosynthesis - Status and Implications of BBN, Big Bang nucleosynthesis - Non-standard BBN

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Big Bang nucleosynthesis begins about one minute after the Big Bang, when the universe has cooled enough to form stable protons and neutrons, after baryogenesis. From simple thermodynamical arguments, one can calculate the fraction of protons and neutrons based on the temperature at this point. This fraction is in favour of protons, because the higher mass of the neutron results in a spontaneous decay of neutrons to protons with a half-life of about 15 minutes. One feature of BBN is that the physical laws and constants that govern the behavi ...

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Big Bang nucleosynthesis, Big Bang nucleosynthesis - Sequence of BBN, Big Bang nucleosynthesis - History of Big Bang nucleosynthesis, Big Bang nucleosynthesis - Heavy elements, Big Bang nucleosynthesis - Helium-4, Big Bang nucleosynthesis - Deuterium, Big Bang nucleosynthesis - Status and Implications of BBN, Big Bang nucleosynthesis - Non-standard BBN

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Structure formation in the big bang model proceeds hierarchically, with smaller structures forming before larger ones. The first structures to form are quasars, which are thought to be bright, early active galaxies and population III stars. Before this epoch, the evolution of the universe could be understood through linear cosmological perturbation theory: that is, all structures could be understood as small deviations from a perfect homogeneous universe. This is computationally relatively easy to study. At this p ...

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Timeline of the Big Bang, Timeline of the Big Bang - The very early universe, Timeline of the Big Bang - The Planck epoch – 10-43 seconds, Timeline of the Big Bang - The Grand Unification Epoch – 10-33 seconds, Timeline of the Big Bang - Cosmic inflation, Timeline of the Big Bang - The early universe, Timeline of the Big Bang - The electroweak epoch – 10-12 s, Timeline of the Big Bang - The hadron epoch – 10-6 s–10-2 s, Timeline of the Big Bang - Nucleosynthesis – 1 s, Timeline of the Big Bang - Matter domination – 70000 years, Timeline of the Big Bang - Recombination – 500000 years, Timeline of the Big Bang - Dark ages, Timeline of the Big Bang - Structure formation, Timeline of the Big Bang - Reionization, Timeline of the Big Bang - Formation of stars, Timeline of the Big Bang - Formation of galaxies, Timeline of the Big Bang - Formation of groups clusters and superclusters, Timeline of the Big Bang - Formation of the solar system, Timeline of the Big Bang - Today, Timeline of the Big Bang - Ultimate fate of the universe, Timeline of the Big Bang - Heat death, Timeline of the Big Bang - Big crunch, Timeline of the Big Bang - Big rip, Timeline of the Big Bang - Vacuum metastability disaster

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All our understanding of the very early universe is very speculative. No accelerator experiments probe sufficiently high energies to provide insight into this period. Scenarios differ radically. Some ideas include the Hartle-Hawking initial state, string landscape, brane inflation, string gas cosmology, and the ekpyrotic universe. Some of these ideas are mutually compatible, others are not. Timeline of the Big Bang - The Planck epoch – 10-43 seconds. See also: Quantum gravit ...

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Timeline of the Big Bang, Timeline of the Big Bang - The very early universe, Timeline of the Big Bang - The Planck epoch – 10-43 seconds, Timeline of the Big Bang - The Grand Unification Epoch – 10-33 seconds, Timeline of the Big Bang - Cosmic inflation, Timeline of the Big Bang - The early universe, Timeline of the Big Bang - The electroweak epoch – 10-12 s, Timeline of the Big Bang - The hadron epoch – 10-6 s–10-2 s, Timeline of the Big Bang - Nucleosynthesis – 1 s, Timeline of the Big Bang - Matter domination – 70000 years, Timeline of the Big Bang - Recombination – 500000 years, Timeline of the Big Bang - Dark ages, Timeline of the Big Bang - Structure formation, Timeline of the Big Bang - Reionization, Timeline of the Big Bang - Formation of stars, Timeline of the Big Bang - Formation of galaxies, Timeline of the Big Bang - Formation of groups clusters and superclusters, Timeline of the Big Bang - Formation of the solar system, Timeline of the Big Bang - Today, Timeline of the Big Bang - Ultimate fate of the universe, Timeline of the Big Bang - Heat death, Timeline of the Big Bang - Big crunch, Timeline of the Big Bang - Big rip, Timeline of the Big Bang - Vacuum metastability disaster

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At this time, the universe is filled with a quark-gluon plasma. Timeline of the Big Bang - The electroweak epoch – 10-12 s. See also: Electroweak force In electroweak symmetry breaking, all the fundamental particles are believed to acquire a mass via the Higgs mechanism in which the Higgs boson acquires a vacuum expectation value. At this time, neutrinos decouple and begin travelling freely through space. This cosmic neutrino background, while unlikely to ever be observed in detail, is analogous ...

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Timeline of the Big Bang, Timeline of the Big Bang - The very early universe, Timeline of the Big Bang - The Planck epoch – 10-43 seconds, Timeline of the Big Bang - The Grand Unification Epoch – 10-33 seconds, Timeline of the Big Bang - Cosmic inflation, Timeline of the Big Bang - The early universe, Timeline of the Big Bang - The electroweak epoch – 10-12 s, Timeline of the Big Bang - The hadron epoch – 10-6 s–10-2 s, Timeline of the Big Bang - Nucleosynthesis – 1 s, Timeline of the Big Bang - Matter domination – 70000 years, Timeline of the Big Bang - Recombination – 500000 years, Timeline of the Big Bang - Dark ages, Timeline of the Big Bang - Structure formation, Timeline of the Big Bang - Reionization, Timeline of the Big Bang - Formation of stars, Timeline of the Big Bang - Formation of galaxies, Timeline of the Big Bang - Formation of groups clusters and superclusters, Timeline of the Big Bang - Formation of the solar system, Timeline of the Big Bang - Today, Timeline of the Big Bang - Ultimate fate of the universe, Timeline of the Big Bang - Heat death, Timeline of the Big Bang - Big crunch, Timeline of the Big Bang - Big rip, Timeline of the Big Bang - Vacuum metastability disaster

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In cosmology, the Alpher-Bethe-Gamow paper (or αβγ paper) was created by Ralph Alpher, at the time a physics PhD student, and his advisor George Gamow. Their work, which would become the subject of Alpher's PhD thesis, argued that the big bang would be expected to create hydrogen, helium and heavier elements in the correct proportions to explain their abundance in the early universe. While the original theory neglected a number of processes important to the formation of heavy elements, subsequent developments showed that big bang nucleosynthesis is consi ...

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Alpher-Bethe-Gamow paper - Bethe's name Alpher-Bethe-Gamow paper - Main shortcoming of the theory

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Chemical evolution has two meanings and uses. The first refers to the theories of evolution of the chemical elements in the universe following the Big Bang and through nucleosynthesis in stars and supernovas. The second use of chemical evolution or chemosynthesis is as a hypothesis to explain how life might possibly have developed or evolved from non-life (see abiogenesis). Various experiments have been made to show certain aspects of this process, the first ones were done by Stanley L. Miller in the 1950s. For th ...

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Below, some of the most active areas of inquiry in cosmology are described, in roughly chronological order. This does not include all of the big bang cosmology, which is presented in cosmological timeline. Physical cosmology - The very early universe. While the early, hot universe appears to be well explained by the big bang from roughly 10-33 seconds onwards, there are several problems. One is that there is no compelling reason, using current particle physics, to expect the universe to be flat, ...

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Physical cosmology, Physical cosmology - History of physical cosmology, Physical cosmology - Areas of study, Physical cosmology - The very early universe, Physical cosmology - Big bang nucleosynthesis, Physical cosmology - Cosmic microwave background, Physical cosmology - Formation and evolution of large-scale structure, Physical cosmology - Dark matter, Physical cosmology - Dark energy, Physical cosmology - Other areas of inquiry, Physical cosmology - External references, Physical cosmology - From groups, Physical cosmology - From individuals

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Modern cosmology developed along tandem observational and theoretical tracks. In 1915, Albert Einstein developed his theory of general relativity. At the time, physicists were prejudiced to believe in a perfectly static universe without beginning or end. Einstein added a cosmological constant to his theory to try to force it to allow for a static universe with matter in it. The so-called Einstein universe is, however, unstable. It is bound to eventually start expanding or contracting. The cosmological solutions of general relativity were found by Alexander Friedmann, whose equations describe the Friedman ...

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Physical cosmology, Physical cosmology - History of physical cosmology, Physical cosmology - Areas of study, Physical cosmology - The very early universe, Physical cosmology - Big bang nucleosynthesis, Physical cosmology - Cosmic microwave background, Physical cosmology - Formation and evolution of large-scale structure, Physical cosmology - Dark matter, Physical cosmology - Dark energy, Physical cosmology - Other areas of inquiry, Physical cosmology - External references, Physical cosmology - From groups, Physical cosmology - From individuals

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Stellar nucleosynthesis Big Bang nucleosynthesis Supernova nucleosynthesis Cosmic ray spallation Astrophysics Nuclear fusion R-process S-process Nuclear fission edit In 1920, Arthur Eddington, on the basis of the precise measurements of atoms by F.W. Aston, was the first to suggest that stars obtained their energy from nuclear fusion of hydrogen to form helium. In 1928, George ...

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Stellar nucleosynthesis, Stellar nucleosynthesis - History, Stellar nucleosynthesis - Key Reactions

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A supernova is a massive explosion of a star that occurs under two possible scenarios.The first is that a white dwarf star undergoes a nuclear based explosion after it reaches its Chandrasekhar limit from absorbing mass from a neighboring star. The second, and more common cause is when a massive star, usually a red giant, loses fuel for the fusion that powers it, it collapses, and combusts from the energy created from the collapse. Stellar nucleosynthesis Big Bang nucleosynthesis Supernova nucleosynthes ...

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Supernova nucleosynthesis, Supernova nucleosynthesis - Supernovae, Supernova nucleosynthesis - Elements fused, Supernova nucleosynthesis - The R-Process

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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. ...

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Big Bang, Big Bang - History, Big Bang - Overview, Big Bang - Theoretical underpinnings, Big Bang - Observational evidence, Big Bang - Hubble's law expansion, Big Bang - Cosmic microwave background radiation, Big Bang - Abundance of primordial elements, Big Bang - Galactic evolution and distribution, Big Bang - Features issues and problems, Big Bang - Horizon problem, Big Bang - Flatness problem, Big Bang - Magnetic monopoles, Big Bang - Baryon asymmetry, Big Bang - Globular cluster age, Big Bang - Dark matter, Big Bang - Dark energy, Big Bang - The future according to the Big Bang theory, Big Bang - Speculative physics beyond the Big Bang, Big Bang - Philosophical and religious interpretations

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In models of the Big Bang, Big Bang nucleosynthesis predicts that within one to three minutes of the Big Bang all the current atomic material in the universe was created producing no heavier element than lithium, but mostly hydrogen and helium. However, although the basic atomic particles of matter were created, atoms themselves could not form in the intense heat. Big Bang chronology of the atom continues to approximately 379,000 years after the Big Bang when the cosmic temperature had dropped to just 3,000 K which allowed the first a ...

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Atom, Atom - Properties of the atom, Atom - Subatomic particles, Atom - Atomic forces, Atom - Atom size and speed, Atom - Elements isotopes and ions, Atom - Valence and bonding, Atom - Atomic spectrum, Atom - Atoms and antimatter, Atom - Atoms and the Big Bang, Atom - History of atomic theory, Atom - Study of atoms

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In models of the Big Bang, Big Bang nucleosynthesis predicts that within one to three minutes of the Big Bang all the current atomic material in the universe was created producing no heavier element than lithium, but mostly hydrogen and helium. However, although the basic atomic particles of matter were created, atoms themselves could not form in the intense heat. Big Bang chronology of the atom continues to approximately 379,000 years after the Big Bang when the cosmic temperature had dropped to just 3,000 K which allowed the first a ...

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Atom, Atom - Properties of the atom, Atom - Subatomic particles, Atom - Atomic forces, Atom - Atom size and speed, Atom - Elements isotopes and ions, Atom - Valence and bonding, Atom - Atomic spectrum, Atom - Atoms and antimatter, Atom - Atoms and the Big Bang, Atom - History of atomic theory, Atom - Philosophical atomism, Atom - Birth of modern atomic theory, Atom - Discovery of subatomic particles, Atom - Study of atomic structure, Atom - Study of atoms

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Since the discovery of the cosmic microwave background by Penzias and Robert Wilson in 1965, most cosmologists have concluded that observations are best explained by the big bang model. However, there have been two periods in which interest in non-standard cosmology has increased due to observational data which posed difficulties for the big bang. The first occurred was the late 1970s when there were a number of unsolved problems such as the horizon problem, the flatness problem, and the lack of magnetic monopoles challenged the big bang mod ...

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Non-standard cosmology, Non-standard cosmology - Non-standard versus standard, Non-standard cosmology - History, Non-standard cosmology - Non-standard cosmologies, Non-standard cosmology - Creationist ideas, Non-standard cosmology - Quasi-steady state, Non-standard cosmology - Tired light, Non-standard cosmology - Variable mass hypothesis and intrinsic redshifts, Non-standard cosmology - Plasma cosmology, Non-standard cosmology - Nucleosynthesis objections to non-standard cosmologies, Non-standard cosmology - Notes, Non-standard cosmology - Bibliography

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Since the discovery of the cosmic microwave background by Penzias and Robert Wilson in 1965, most cosmologists have concluded that observations are best explained by the big bang model. However, there have been two periods in which interest in non-standard cosmology has increased due to observational data which posed difficulties for the big bang. The first occurred was the late 1970s when there were a number of unsolved problems such as the horizon problem, the flatness problem, and the lack of magnetic monopoles challenged the big bang mod ...

See also:

Non-standard cosmology, Non-standard cosmology - Non-standard versus standard, Non-standard cosmology - History, Non-standard cosmology - Non-standard cosmologies, Non-standard cosmology - Creationist ideas, Non-standard cosmology - Quasi-steady state, Non-standard cosmology - Tired light, Non-standard cosmology - Variable mass hypothesis and intrinsic redshifts, Non-standard cosmology - Plasma cosmology, Non-standard cosmology - Self Creation Cosmology, Non-standard cosmology - Nucleosynthesis objections to non-standard cosmologies, Non-standard cosmology - Notes, Non-standard cosmology - Bibliography

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Non-standard cosmologies are usually not considered by physicists, because the essentials of the big bang theory have been confirmed by a wide enough range of complementary observations that they believe there is little chance of the theory being replaced in its essentials. A well known letter by advocates of non-standard cosmology has affirmed this: "today, virtually all financial and experimental resources in cosmology are devoted to big bang studies." [ ...

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Non-standard cosmology, Non-standard cosmology - Non-standard versus standard, Non-standard cosmology - History, Non-standard cosmology - Non-standard cosmologies, Non-standard cosmology - Creationist ideas, Non-standard cosmology - Quasi-steady state, Non-standard cosmology - Tired light, Non-standard cosmology - Variable mass hypothesis and intrinsic redshifts, Non-standard cosmology - Plasma cosmology, Non-standard cosmology - Nucleosynthesis objections to non-standard cosmologies, Non-standard cosmology - Notes, Non-standard cosmology - Bibliography

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Non-standard cosmologies are usually not considered by physicists, because the essentials of the big bang theory have been confirmed by a wide enough range of complementary observations that they believe there is little chance of the theory being replaced in its essentials. A well known letter by advocates of non-standard cosmology has affirmed this: "today, virtually all financial and experimental resources in cosmology are devoted to big bang studies." [ ...

See also:

Non-standard cosmology, Non-standard cosmology - Non-standard versus standard, Non-standard cosmology - History, Non-standard cosmology - Non-standard cosmologies, Non-standard cosmology - Creationist ideas, Non-standard cosmology - Quasi-steady state, Non-standard cosmology - Tired light, Non-standard cosmology - Variable mass hypothesis and intrinsic redshifts, Non-standard cosmology - Plasma cosmology, Non-standard cosmology - Self Creation Cosmology, Non-standard cosmology - Nucleosynthesis objections to non-standard cosmologies, Non-standard cosmology - Notes, Non-standard cosmology - Bibliography

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Gamow humourously decided to add the name of his friend—the eminent physicist Hans Bethe—to this paper in order to create the whimsical author list of Alpher, Bethe, Gamow, which is a play on the Greek letters: Alpha, Beta, Gamma (α, β, γ). In his 1952 book, The Creation of the Universe, Gamow explained Hans Bethe's association with the theory this way. After this Bethe did work on big bang nucleosynthesis. Alpher, at the time only a graduate student, was generally dismayed by the inclusion of Bethe's name on this ...

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Alpher-Bethe-Gamow paper, Alpher-Bethe-Gamow paper - Bethe's name, Alpher-Bethe-Gamow paper - Main shortcoming of the theory

Read more here: » Alpher-Bethe-Gamow paper: Encyclopedia II - Alpher-Bethe-Gamow paper - Bethe's name