July 18, 2024
The universe as a quantum many-body system Speaker: Daniele Oriti | LMU München & MCQST Abstract Several approaches to quantum gravity suggest that spacetime and geometry are emergent from non-spatiotemporal quantum structures. In some of them, the fundamental quantum entities admit (in some approximation) a simplicial geometric description and can be mapped to generalized tensor networks. This allows also for a primitive entanglement/geometry correspondence. I summarize this formulation of the universe as a quantum many-body system, these immediate consequences as well as more recent results about holographic behavior. Then, I suggest possible lines of further developments from this perspective. Finally, I discuss how the hydrodynamic description of the same system, treated as a quantum fluid, can be given a cosmological interpretation and present a number of recent results about the resulting effective cosmological dynamics, including the replacement of the big bang singularity with a quantum bounce and a late-time accelerated behavior reproducing a phantom-like dark energy from pure quantum gravity origin.