MG13 - Talk detail |
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Participant |
Kolionis, Giorgos | |||||||
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Institution |
University of the Aegean - Gorgiras and Palama - Karlovasi - Samos - Greece | |||||||
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Session |
GT2 |
Accepted |
Yes |
Order |
9 |
Time |
20' | |
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Talk |
Oral abstract |
Title |
Global cosmological stability of the initial state in quadratic gravity theories | |||||
| Co-authors | S. Cotsakis, A. Tsokaros | |||||||
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Abstract |
We use asymptotic methods to study the global stability of solutions near the initial singular state of isotropic models in quadratic lagrangian theories of gravity and record all possible modes of approach to the initial singularity in such models. In particular, we show that a ‘radiation’ solution is a global attractor to both flat and curved universes in these theories near a finite-time singularity. For negatively curved universes, we find that asymptotically they are all dominated by a stable Milne-type cosmological solution, and there are no other possible dominant features on approach to the singularity in these models. These results allow us to conclude a global singularity theorem valid conformally with the initial state of the Einstein-scalar field system characterized by the scalar field blowing up like lnt, and the Hubble parameter diverging as 1/t. |
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