Speaker：Sebastian Grieninger
Time：January 29,202116：00PM（Beijing Time）
Venue：302，Physics Building
Online report（ZOOM ID：829 6003 8091 Passcode: 369963）
Abstract:We investigate entanglement entropies in the context of the DS/dS correspondence. Interestingly, we find that there exists a one parameter family of bulk minimal surfaces that all have the same area. We also show that in the presence of extra matter fields the former entanglement entropy always exceeds the dS entropy. We interpret this result in the context of entropy bounds in de Sitter space and the swampland program.
Furthermore, we consider the entanglement entropies in (A)dS(d+1) in the presence of a hard radial cutoff and compute the entanglement entropy for generic intervals on the cutoff slice analytically and interpret them in terms of TTbar deformations. Surprisingly, we find that we may write the entanglement entropies formally in the same way as the entanglement entropy for antipodal points on the sphere by introducing an effective radius Reff=Rcos(βϵ). Geometrically, this is equivalent to following the TTbar trajectory until the generic interval corresponds to antipodal points on the sphere. Finally, we match the entanglement entropies for antipodal points explicitly on the field theory and gravitational side by considering the Wald entropies.
Brief Bio:Sebastian Grieninger obtained his PhD in 2020 from the Friedrich-Schiller University of Jena, Germany under the supervision of Prof. Martin Ammon. During his PhD, he was granted a Fulbright scholarship to visit the University of Washington, Seattle (USA) for 19 months. At the University of Washington he was working under the supervision of Prof. Andreas Karch on quantum information theoretic aspects of Holography in particular on entanglement entropies and swampland bounds in context of the so-called DS/dS correspondence and T\bar T deformations. In his Master and PhD thesis, he investigated the far- and close-to-equilibrium effects of chiral anomalies and (spontaneously) broken spacetime symmetries on the transport behavior of strongly coupled field theories. After his PhD, he was granted a DAAD scholarship to join the group of Prof. Anton Rebhan at the Vienna University of Technology in Austria for 6 months. As of November 2020, he is a Postdoctoral Researcher in the group of Prof. Karl Landsteiner and Dr. Daniel Areán at the Institute for Theoretical Physics at the Universidad Autónoma de Madrid/CSIC in Spain.
