A Dying Universe - Long-Term Fate of Astrophys. Objects [lg by F. Adams, G. Laughlin PDF

By F. Adams, G. Laughlin

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01M⊙. During the proton decay phase of evolution, a white dwarf 12/5 follows a well-defined track in the H-R Diagram given by L∗ ∝ T∗ . After the stellar mass decreases −3 to M∗ ≈ 10 M⊙ , the star is lifted out of degeneracy and follows a steeper track L∗ ∝ T∗12 in the H-R Diagram. [10] If proton decay does not take place through the first order process assumed above, then white dwarfs and other degenerate objects will still evolve, but on a much longer time scale. The relevant physical process is likely to be proton decay through higher order effects.

The physical laws of the universe, or at least the values of all of the physical constants, would change as the phase transition completes (see Sher, 1989 and Crone & Sher, 1990 for a discussion of changing laws of physics during a future phase transition). The universe, as we know it, would simply cease to exist. 40 Vacuum tunneling of the entire universe is certainly one of the more speculative topics considered in this paper. Nevertheless, its inclusion is appropriate since the act of tunneling from a false vacuum into a true vacuum would change the nature of the universe more dramatically than just about any other physical process.

8] We have discussed the allowed range for the proton lifetime. A firm lower bound on the lifetime arises from current experimental searches. Although no definitive upper limit exists, we can obtain a suggestive upper “bound” on the proton lifetime by using decay rates suggested by GUTs and by invoking the constraint the mass of the mediating boson, MX < MPl ∼ 1019 GeV. , the number of mediating bosons required for the decay to take place. Even for the third order case, we have ηP < 201. Quantum gravity effects also lead to proton decay with time scales in the range 46 < ηP < 169.

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A Dying Universe - Long-Term Fate of Astrophys. Objects [lg article] by F. Adams, G. Laughlin

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