ausblenden:
Schlagwörter:
High Energy Physics - Theory, hep-th,General Relativity and Quantum Cosmology, gr-qc
Zusammenfassung:
When general relativity is augmented by quadratic gravity terms, it becomes a
renormalisable theory of gravity. This theory may admit a non-Gaussian fixed
point as envisaged in the asymptotic safety program, rendering the theory
trustworthy to energies up to the Planck scale and even beyond. We show that
requiring physical solutions to have a finite action imposes a strong selection
on big-bang-type universes. More precisely we find that, in the approach to
zero volume, both anisotropies and inhomogeneities are suppressed while the
scale factor is required to undergo accelerated expansion. This provides
initial conditions which are favourable to the onset of an inflationary phase
while also providing a suitable starting point for the second law of
thermodynamics in the spirit of the Weyl curvature hypothesis.
