Big Bang Nucleosynthesis - QuarkNet
Big Bang Nucleosynthesis
Big-Bang Nucleosynthesis - INSPIRE-HEP
Fred Hoyle, the atheist British astronomer who formulated the theory of stellar nucleosynthesis and originally coined the term, "Big Bang" on March 28, 1949 had this to say at the end of his career three decades later (Note: There are about 2,000 enzymes in the simplest cell, a bacterium, and 'only' about atoms in the entire universe.):
occurred within the first three minutes of the beginning of theuniverse and is responsible for much of the abundance ratios of1H (), 2H (), 3He(), and4He (),in the universe .Although 4He continues to be produced by othermechanisms (such as stellar fusion and alpha decay) and traceamounts of 1H continue to be produced by and certaintypes of radioactive decay ( and ), most of the mass of these isotopes in the universe,and all but the insignificant traces of the 3He anddeuterium in the universe produced by rare processes such as , arethought to have been produced in the . The nuclei of these elements, alongwith some 7Li, and 7Be are believed to havebeen formed when the universe was between 100 and 300 seconds old,after the primordial - plasma froze out to form and . Because of the very short period inwhich Big Bang nucleosynthesis occurred before being stopped byexpansion and cooling, no elements heavier than could be formed. (Elements formedduring this time were in the plasma state, and did not cool to thestate of neutral atoms until much later).
Big bang nucleosynthesis - ScienceDirect
The MAP satellite (microwave anisotropy probe) should be able to directlymeasure this matter density and compare the observed value to the predictions ofBig Bang nucleosynthesis. This will be an important test of the model.
The amount of He produced during the big bang nucleosynthesis is mainly determined by the neutron toproton ratio at the freeze-out of the weak interactions that interconvert neutrons and protons. The result ofBig Bang nucleosynthesis (BBN) thus depends on , , and respectively throughthe expansion rate, the neutron to proton ratio, the neutron-proton mass difference and thenuclear reaction rates, besides the standard parameters such as, e.g., the number of neutrinofamilies.
This was Big Bang nucleosynthesis
The term nucleosynthesis refers to the formation of heavy elements, atomicnuclei with many protons and neutrons, from the collision of light elements. TheBig Bang theory predicts that the early universe was a very hot place. Onesecond after the Big Bang, the temperature of the universe was roughly 10billion degrees and was filled with a sea of neutrons, protons, electrons,anti-electrons (positrons), photons and neutrinos. As the universe cooled, theneutrons either decayed into protons and electrons or combined with protons tomake deuterium.
In the time period between about 100 seconds and 30 minutes after the Big Bang, but mostly with the first three minutes, the temperature and density of the universewere appropriate for the efficient synthesis of the light elements. Just as in theSun, some of the hydrogen nuclei were underwent fusion to form heavier nuclei including helium nuclei. This was the era of primordial nucleosynthesis.The current abundances of the light elements reflect what occurred during theepoch of primordial nucleosynthesis and therefore place strong constraints onthe state of the universe and the baryon density during that time.
Big Bang Nucleosynthesis - Springer
Big Bang Nucleosynthesis - Internet Archive
nucleosynthesis – Starts With A Bang
Big bang nucleosynthesis - University of Adelaide
3.8 Big bang nucleosynthesis
Big bang nucleosynthesis - Revolvy
The Universe Adventure - Nucleosynthesis
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