Las mañanas IFCA con Philipp Strasberg: "Everything everywhere all at once? Towards a quantitative understanding of many worlds"
Start date: 17/10/2023 12:00
End date: 17/10/2023 13:00
Everything everywhere all at once? Towards a quantitative understanding of many worlds
Everett's many worlds interpretation (MWI) is one of the most widely discussed topics in contemporary fundamental science, yet discussions of it most often remain at a superficial and qualitative level. The goal of this talk is to convince you that a more quantitative discussion is needed and possible using tools from statistical mechanics. To this end, I start by introducing the MWI and its problems. I then review the decoherent histories formalism, which allows to address various problems of the MWI. Based on it, the following two (mostly numerical) results are discussed.
First, I argue that the basic mechanism of decoherence are slow and coarse observables of isolated non-integrable many-body systems. Those show exponentially suppressed interference effects as a function of the particle number of the system, if probed a few times. However, things start to change drastically for very long histories (e.g., many repetitions in a quantum coin flip experiment). The "branches" of the many worlds "tree" then suddenly acquire a non-trivial structure, with decoherence surviving only on a very small subset of branches. Remarkably, those surviving classical branches are exactly those that sample frequencies according to Born's rule.
Philipp Strasberg got his PhD in 2015 from the Technical University in Berlin. Postdoctoral experience in Luxembourg then in 2018 joined the quantum information group at the Universitat Autonoma de Barcelona. Currently a postdoctoral junior leader grant from “la Caixa” foundation. He has published over 30 scientific articles (including several single-author articles and a book) about quantum and classical stochastic processes, quantum transport and mesoscopic physics, quantum thermodynamics, quantum many-body systems and the quantum-to-classical transition.
La charla tendrá lugar en la Sala Luis Pesquera del IFCA a las 12:00 y en streaming a través del canal de YouTube del IFCA. Café previo a las 11:45.