Black Holes: Difference between revisions

But that's only for mid-sized stars. For more massive stars, the core is bigger and thus this process starts much earlier. Following the exhaustion of hydrogen and the fusing of iron in the star core, the star (which from the outside is now a red supergiant as big as Jupiter's orbit) has an onion-like core of shells made up of the first twenty-five elements of the periodic table. The star's core becomes so hot that even those elements start to combine -- but because the binding energies of the nuclei of all elements following iron decrease successively, further fusion results in the loss of energy, rather than the release, so even as the core starts making serious elements like gold, bismuth and uranium, it can't support its own weight and collapses further, taking in more mass. If the star's mass was greater than the Chandrasekhar limit (1.4 solar masses), electron degeneracy pressure breaks down completely<ref>electrons of the same spin cannot occupy the same space; this prevents matter from collapsing, unless gravity is really kicking matter's ass</ref> because gravity merges electrons and protons together to form neutrons and the neutron star is born from dying star's core, when outer layers are blown away. The neutron star is held up against its weight by the neutron degeneracy pressure (notice a theme here?). But if the core exceeds the Tolman-Oppenheimer-Volkoff limit (about two to three solar masses, and definitely no more than five, but it's still unclear), neutron degeneracy pressure will break down as well and neutrons are merged. What should happen with matter in such case is uncertain, but the size of heavy neutron star is already close to that of black holes of same mass and so it can be assumed, that resulting object collapse below event horizon and gravity condenses the core down to a point in space that is [[Divide Byby Zero|infinitely small, yet immensely massive and infinitely dense (Density is, after all, mass divided by volume)]], called a singularity, similar to the theoretical beginning state of the universe in the Big Bang Theory. So small and so massive, not even light can escape. Or it should if initial mass was not rotating. However, it is not the case and usually a rotating black hole is formed, that is even more alien.