Hi all, Next Monday we will have two seminars: (1) Heiko Schwab will tell us about “Quantum Resource Trade-offs in Quantum Reference Frames on the Lattice” (2) Lucas Hörl will tell us about “Quantum extremal surfaces and the black hole information problem” See below for the abstracts. The talks will take place on Monday at 16:45 in HIT K52. Best, Ladina %%%%%%% Title: Quantum Resource Trade-offs in Quantum Reference Frames on the Lattice Abstract: The study of quantum reference frames (QRFs) and their transformations has demonstrated the relational nature of entanglement and coherence. Motivated by the central role these quantum resources play in quantum information processing, it was recently shown that the sum of particular quantifiers of these resources remains invariant under ideal QRF transformations. A first step in generalizing this result from the quantum information- to the field-theoretic setting is to consider quantum reference frames on a spatial lattice. Inspired by the Hamiltonian formulation of lattice gauge theory, we propose a possible extension of the perspective-neutral formulation of QRFs to the lattice by explicitly considering a Z_2 gauge theory and analyze the entanglement-coherence trade-off for QRFs on the lattice in this concrete case. This leads us to propose a quantum resource trade-off for transformations between ideal and non-ideal QRFs on the lattice in terms of a generalized invariant with an operational meaning as a relative entropy. %%%%%%%%% Title: Quantum extremal surfaces and the black hole information problem Abstract: This talk reviews the quantum extremal surface prescription and its role in the black hole information problem. Starting from the Bekenstein-Hawking entropy, I introduce holographic entanglement entropy, the Ryu-Takayanagi formula, and its quantum generalization leading to the island rule. I then discuss the information problem in a concrete toy model, namely two-dimensional JT gravity coupled to a non-gravitating bath. In this setting, the replica trick, including the contributions from replica wormhole saddles, gives a controlled derivation of the Page curve for Hawking radiation. I conclude with a brief overview of my semester project, which studies corrections to this semiclassical picture, and makes steps towards understanding the radiation of black holes prepared in superpositions of semiclassical geometries and one-loop corrections to JT gravity coupled to a bath.