big bang nucleosynthesis

E24000

Big bang nucleosynthesis is the early-universe process, occurring within the first few minutes after the Big Bang, in which light atomic nuclei such as hydrogen, helium, and small amounts of other elements were formed.


Statements (49)
Predicate Object
instanceOf cosmological process
nucleosynthesis process
physical process
alsoKnownAs BBN
primordial nucleosynthesis
constrains baryon density of the universe
number of relativistic species in the early universe
possible new physics beyond the Standard Model
dependsOn baryon-to-photon ratio
expansion rate of the universe
neutron-to-proton ratio
number of light neutrino species
differentFrom stellar nucleosynthesis
doesNotProduce significant amounts of elements heavier than lithium
endsWhen universe becomes too cool and diffuse for further nuclear fusion
explainsAbundanceOf primordial deuterium
primordial helium
primordial lithium
follows quark–hadron transition
hasOpenProblem cosmological lithium problem
helium4MassFraction about 25 percent
hydrogenMassFraction about 75 percent
involves neutron–proton interconversion
nuclear fusion reactions
weak interaction processes
occursAtRedshift greater than 10^8
occursAtTemperature about 0.1 to 1 MeV
about 1 billion kelvin
occursIn early universe
precedes formation of the cosmic microwave background
recombination
primaryProduct helium-4
hydrogen-1
produces deuterium
helium-3
helium-4
hydrogen-1
light atomic nuclei
lithium-7
trace amounts of beryllium-7
providesEvidenceFor Big Bang model
relatedTo stellar nucleosynthesis
sensitiveTo cosmological parameters
startsWhen universe cools below about 1 billion kelvin
studiedIn astrophysics
physical cosmology
tests standard cosmological model
timeAfterBigBang approximately 1 to 20 minutes
first few minutes

Referenced by (4)
Subject (surface form when different) Predicate
Albedo 0.39 ("Nucleogenesis (Part One)")
hasTrack
Big Bang cosmology ("Big Bang nucleosynthesis")
includes
deuteron
isProducedIn
James Peebles ("Big Bang nucleosynthesis")
knownFor

Please wait…