Séminaire / Seminar GReCO |
| « Bouncing universes from the perspective of group field theory and minisuperspace models » |
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Lisa Mickel |
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In the spirit of finding a quantum description
for gravity and understanding the origin of our universe we will explore the early quantum cosmos from two perspectives: group field theory and minisuperspace models. Group field theory is a background-independent approach to quantum gravity in which field excitations are seen as elementary building blocks of space. We will discuss how a bouncing universe emerges in the cosmological sector of the theory. Using a recent proposal to extract and effective metric from group field theory, we will also sketch an avenue to include cosmological perturbations in the framework. In minisuperspace models one quantises the reduced classical system, in this case the flat FLRW spacetime (with perturbations). We focus on the case in which the state of the universe is given by a superposition and consider the effects on the bounce dynamics, where we extract the effective scale factor from quantum trajectories. |
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lundi 19 mai 2025 - 11:00 Salle des séminaires Évry Schatzman Institut d'Astrophysique de Paris |
| Pages web du séminaire / Seminar's webpage |