14 research outputs found
Asymptotic silence of generic cosmological singularities
In this letter we investigate the nature of generic cosmological
singularities using the framework developed by Uggla et al. We do so by
studying the past asymptotic dynamics of general vacuum G2 cosmologies, models
that are expected to capture the singular behavior of generic cosmologies with
no symmetries at all. In particular, our results indicate that asymptotic
silence holds, i.e., that particle horizons along all timelines shrink to zero
for generic solutions. Moreover, we provide evidence that spatial derivatives
become dynamically insignificant along generic timelines, and that the
evolution into the past along such timelines is governed by an asymptotic
dynamical system which is associated with an invariant set -- the silent
boundary. We also identify an attracting subset on the silent boundary that
organizes the oscillatory dynamics of generic timelines in the singular regime.
In addition, we discuss the dynamics associated with recurring spike formation.Comment: 4 pages, 5 *.eps figures, RevTeX4; replaced by significantly revised
version, to appear in Physical Review Letter