Specifically, the theory yields precise quantitative predictions for the mixture of these elements, that is, the primordial abundances at the end of the big-bang. The denser the initial universe was, the more deuterium would be converted to helium-4 before time ran out, and the less deuterium would remain.
Triggered by the separation of the strong nuclear forcethe universe undergoes an extremely rapid exponential expansion, known as cosmic inflation. If this happens, all structures will be destroyed instantaneously, without any forewarning.
The nuclear chemistry described above is confirmed by high energy physics experiments at CERNthe Stanford Linear Accelerator and a few similar establishments that can reproduce the conditions fractions of a second after the Big Bang, albeit on a small scale.
More recent evidence includes observations of galaxy formation and evolutionand the distribution of large-scale cosmic structures These are sometimes called the "four pillars" of the Big Bang theory. The hadron epoch Main article: Population II stars are formed early on in this process, with Population I stars formed later.
At this point, the elemental abundances were nearly fixed, and only change was the result of the radioactive decay of the two major unstable products of BBN, tritium and beryllium This first process, Big Bang nucleosynthesiswas the first type of nucleogenesis to occur in the universe.
Star formation The first stars, most likely Population III stars, form and start the process of turning the light elements that were formed in the Big Bang hydrogen, helium and lithium into heavier elements.
There is light but not light we could observe through telescopes. Population II stars are formed early on in this process, with Population I stars formed later.
This expression also shows how a different number of neutrino flavors will change the rate of cooling of the early universe.
This metric contains a scale factorwhich describes how the size of the universe changes with time. As the strong nuclear force separates from the other two, particle interactions create large numbers of exotic particlesincluding W and Z bosons and Higgs bosons the Higgs field slows particles down and confers mass on them, allowing a universe made entirely out of radiation to support things that have mass.
The temperature of the universe cools to about a trillion degrees, cool enough to allow quarks to combine to form hadrons like protons and neutrons. Although the baryon per photon ratio is important in determining elemental abundances, the precise value makes little difference to the overall picture.
This is thought to have occurred aboutyears after the Big Bang. Stellar Nucleosynthesis This would be the end of the story, except that the rapidly expanding universe had a built in brake — gravity, the great sculptor — which operated both globally and locally.
This phase transition triggers a period of exponential expansion known as cosmic inflation. Such dark energy is called phantom energy and is unlike any known kind of energy. A teoria do Big Bang depende de duas suposições principais: a universalidade das leis da física e o princípio cosmológico, que afirma que, em grandes escalas, o universo é homogêneo e sgtraslochi.com ideias foram inicialmente tomadas como postulados, mas hoje há esforços para testar cada uma delas.
Since the Big Bang, billion years ago, the universe has passed through many different phases or epochs.
Due to the extreme conditions and the violence of its very early stages, it arguably saw more activity and change during the first second than in all the billions of years since.
Big Bang nucleosynthesis began roughly 10 seconds after the big bang, when the universe had cooled sufficiently to allow deuterium nuclei to survive disruption by high-energy photons. (Note that the neutron-proton freeze-out time was earlier).
Timeline of cosmological theories Big Bang nucleosynthesis produced very few nuclei of elements heavier than lithium due to a bottleneck: the absence of a stable nucleus with 8 or 5 nucleons.
This deficit of larger atoms also limited the amounts of lithium-7 produced during BBN. In physical 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.
Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons, primarily protons and sgtraslochi.com first nuclei were formed about three minutes after the Big Bang, through the process called Big Bang sgtraslochi.comeen minutes later the universe had cooled to a point at which these processes ended, so only the fastest and simplest reactions occurred, leaving.Timeline of big bang nucleosynthesis