- #1
wolram
Gold Member
Dearly Missed
- 4,446
- 558
Why do we live in such a privileged time?
arXiv:1810.10547 [pdf, ps, other]
The End of Cosmic Growth
Eric V. Linder, David Polarski
Comments: 5 pages, 6 figures
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
The growth of large scale structure is a battle between gravitational attraction and cosmic acceleration. We investigate the future behavior of cosmic growth under both general relativity (GR) and modified gravity during prolonged acceleration, deriving analytic asymptotic behaviors and showing that gravity generally loses and growth ends. We also note the `why now' problem is equally striking when viewed in terms of the shut down of growth. For many models inside GR the gravitational growth index γ also shows today as a unique time between constant behavior in the past and a higher asymptotic value in the future. Interestingly, while f(R) models depart in this respect dramatically from GR today and in the recent past, their growth indices are identical in the asymptotic future and past.
arXiv:1810.10547 [pdf, ps, other]
The End of Cosmic Growth
Eric V. Linder, David Polarski
Comments: 5 pages, 6 figures
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
The growth of large scale structure is a battle between gravitational attraction and cosmic acceleration. We investigate the future behavior of cosmic growth under both general relativity (GR) and modified gravity during prolonged acceleration, deriving analytic asymptotic behaviors and showing that gravity generally loses and growth ends. We also note the `why now' problem is equally striking when viewed in terms of the shut down of growth. For many models inside GR the gravitational growth index γ also shows today as a unique time between constant behavior in the past and a higher asymptotic value in the future. Interestingly, while f(R) models depart in this respect dramatically from GR today and in the recent past, their growth indices are identical in the asymptotic future and past.