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Heavy elements couldn't form right after the Big Bang because there aren't any stable nuclei with 5 or 8 nucleons. Source: Wikipedia (user Pamputt) In the Big Bang nucleosynthesis, the main product was $^4He$, because it is the most stable light isotope: 20 minutes after the Big Bang, helium-4 represented about 25% of the mass of the Universe, and the ...


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In the case of a supernova explosion it is possible to create heavy elements through fusion. Supernovae have a tremendous amount of energy in a very small volume but not as much energy per volume as there was in our early universe. So, what is the major difference? Why didn't the Big Bang create heavy elements? I just want to point out, too much ...


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This question is answered in detail by the so-called "Big Bang Nucleosynthesis", the theory about the creation of the nuclei in the early Universe. Almost out of nothing, it allows one to determine that 75% of the nuclear mass was coming in hydrogen, 25% in helium, and some small traces of lithium appeared, too. Even though Gamow used to think that all ...


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I'll approach this slightly differently. The abundance of Li in the solar system and in the Earth's crust is low compared with elements like carbon, oxygen, silicon and iron. The solar system lithium is created partly (only 10%) by primordial nucleosynthesis, a bit by spallation reactions of cosmic rays on nuclei in the interstellar medium, but mainly in ...


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The farthest radiation we can see is from the particle horizon. Not quite right. It is quite hard to see light through a plasma. Note that we can see the surface of the sun, but it is hard to see the inside (and not just because the light from the center takes so long to get out from repeated scattering, it also just is hard to image because it ...


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There is no reason why we could not be viewing the BB in our frame. We can only view anything from our position in space-time, and in our frame. We don't see the whole BB 3-sphere, just that 2-sphere section of it which is located at just the right distance that light can reach us in the time that has since elapsed. That's why what we see is spread over a ...



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