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emanaly
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How are Nucleosynthesis and Hubble expansion are considered as an evidence for the Big Bang Theory?
I have a question. Of the 3/4 hydrogen, is most at this time (before the stars) in the form of the hydrogen atom [P+e-] or deuterium atom [NP+e-) ? And concerning the nucleosynthesis of the neutron [N]--is it more in deuterium [NP+e-] atom at this time (before the stars) or helium-3 [2P+2e- plus N] or just free as unstable [N] ? Thanks for any information.Garth said:...This means that before the stars existed the universe must have consisted of "3/4" hydrogen and "1/4" helium and only trace amounts of other elements...
which neatly summarises the observed element abundances. You then go on to say:Garth said:The baryonic universe appears to consist of "3/4" hydrogen "1/4" helium and 2% everything else...
This neatly accounts for the presence of the elements that are heavier than Helium by the nucleosynthesis of such elements in stars and sounds like a plausible argument, as does:...When the required total amount of hydrogen, helium and their products is calculated to produce this total luminosity over this projected age it is found that only the 2% everything else can be accounted for. (2% of the hydrogen turns into helium which then turns into the "2%" of all the other elements.)
and:...before the stars existed the universe must have consisted of "3/4" hydrogen and "1/4" helium and only trace amounts of other elements.
.It was found that this is precisely what is predicted by the nucleosynthesis processes of the Big Bang. This primordial element relative abundance gave strong verification of the BB theory.
If no antiparticles survived this process (eg., before the stars were formed), then how do you explain the existence of the various pions (with quark+antiquark) that now exist ? Are you saying pions (and other entities with antimatter that we know) were formed "from the stars", and not before ?Garth said:..At an earlier stage matter and antimatter annihilated each other. Because of a slight imbalance there was ~ 108 antiparticles to (108+1) particles...no antiparticles survived this process...
Garth said:...Other considerations...are consistent with another matter component of exotic non-baryonic Dark Matter - of 23% critical density.
Cosmic acceleration and spatial flatness from the CMB anisotropies data require another component of Dark Energy to bring the total density up to the critical density or just above it.
If you are happy to accept this DM and DE, which has not yet been discovered in the laboratory, then there is no conflict.
oldman said:I don't see how anyone can be happy about such ad hoc solutions to such serious problems. The following quote is relevant:
(A physical) “theory must not contradict empirical facts. However evident this demand may in the first place appear, its application turns out to be quite delicate. For it is often, perhaps even always, possible to adhere to a general theoretical foundation by securing the adaptation of the theory to the facts by means of additional artificial assumptions.” ...
Einstein, A.: 1949, in Albert Einstein: Philosopher Scientist, P. A. Schilpp (ed.), Harper & Row, New York. p. 23.
Garth said:...I am not happy with these additional assumptions, that is, not until they are independently confirmed in 'the laboratory'... The cosmological community as a whole is convinced that the Higgs Boson/Inflaton necessary for Inflation, the non-baryonic DM particle and DE are all real and about to be discovered.
Garth
Nucleosynthesis is the process by which heavier elements are formed from lighter elements. It occurs in the cores of stars through nuclear fusion reactions, where high temperatures and pressures cause atoms to combine and form new elements.
Nucleosynthesis is responsible for the production of all elements in the universe except for hydrogen and helium, which were created during the Big Bang. This process is vital for the formation of planets, stars, and ultimately, life.
Hubble expansion is the observation that the universe is expanding at an accelerating rate. This expansion is driven by dark energy and is responsible for the distance between galaxies increasing over time.
Scientists have observed the redshift of light from distant galaxies, indicating that they are moving away from us. This is known as the Hubble redshift and is strong evidence for the expansion of the universe.
While we cannot recreate the extreme conditions of nucleosynthesis or observe Hubble expansion in a laboratory, scientists can study the effects of these processes through experiments and simulations. This allows us to better understand the formation and evolution of the universe.