In physical cosmology, Big Bang nucleosynthesis (also known as primordial nucleosynthesis, and abbreviated as BBN) [1] is a model for the production of light nuclei, deuterium, 3 He, 4 He, 7 Li, between 0.01s and 200s in the lifetime of the universe. [2]

The Big Bang Nucleosynthesis theory predicts that roughly 25% the mass of the Universe consists of Helium. It also predicts about 0.01% deuterium, and even smaller quantities of lithium. The important point is that the prediction depends critically on the density of baryons (ie neutrons and protons) at the time of nucleosynthesis.

Big Bang nucleosynthesis provides the earliest probe of standard model physics, at a time when the universe was less than 1000 seconds old. It determines the abundances of the lightest nuclides, which give rise to the subsequent history of the visible matter in the universe.

Big Bang Nucleosynthesis is the process by which light elements formed during the Big Bang. The agreement between predicted abundances and inferences from observations of primordial (pre-stellar) …

From about one second to a few minutes cosmic time, when the temperature has fallen below 10 billion Kelvin, the conditions are just right for protons and neutrons to combine and form certain species of atomic nuclei. This phase is called Big Bang Nucleosynthesis.

Theory of Big Bang Nucleosynthesis The relative abundances of the lightest elements (hydrogen, deuterium, helium-3 and helium-4, and some lithium and beryllium) provide a strong test of the hypothesis that the universe was once far hotter and denser than it …

2012年9月26日 · Big Bang Nucleosynthesis Gamow, Alpher and Herman proposed the hot Big Bang as a means to produce all of the elements. However, the lack of stable nuclei with atomic weights of 5 or 8 limited the Big Bang to producing hydrogen and helium.

2024年3月31日 · Big Bang Nucleosynthesis is the process by which the nuclei of light elements such as hydrogen, helium, and lithium were formed in the early universe. It occurred within the first few minutes after the Big Bang, when the universe was hot and dense enough for nuclear reactions to take place.

The process of forming the hydrogen and helium and other trace constituents is often called "big bang nucleosynthesis". Schramm's figures for relative abundances indicate that helium is about 25% by mass and hydrogen about 73% with all other elements constituting less than 2%.

2021年12月1日 · Big-Bang nucleosynthesis (BBN) offers the deepest reliable probe of the early Universe, being based on well-understood Standard Model physics [1].