др Михаило Чубровић

21. децембра 2020.

У оквиру семинара Центра за изучавање комплексних система Института за физику у Београду, у четвртак, 24. децембра 2020. године у 14 часова путем Zoom платформе, др Михаило Чубровић (Лабораторија за примену рачунара у науци, Институт за физику у Београду) одржаће предавање:

No free lunch: how strong correlations and chaotic wormholes kill teleportation


In this talk we will consider two distinct but somewhat analogous phenomena: traversable wormholes („shortcuts“ through spacetime) and quantum teleportation (instantaneous transfer of quantum information). Both are known to be possible under certain circumstances, mainly in idealized setups at zero density and temperature. We will consider the dynamics of finite density matter in the vicinity of a model traversable wormhole and show that the scattering is very strongly chaotic (exhibiting so-called Wada basins), which in turn introduces strong instabilities that generically destroy the wormhole. Similarly, quantum teleportation between two strongly coupled spin systems (generalized Sachdev-Ye-Kitaev models) introduces large and long-living perturbations (computed within the mean-field theory). We will find out that teleportation between large and strongly interacting systems is much more difficult. As a sanity check, we will repeat the wormhole calculation in anti-de Sitter (AdS) space where, through the AdS/CFT correspondence, it becomes exactly equivalent (rather than just analogous) to two entangled Sachdev-Ye-Kitaev systems, and again find that the wormhole/entanglement likely does not survive the transport/teleportation attempt. On a brighter side, these negative results soften the black hole information paradox in AdS space: since the teleportation (in this case between Alice outside the black hole and Bob inside it) is much slower and much more fragile than usually assumed, the no-cloning theorem can be satisfied and there is likely no unitarity violation.

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Meeting ID: 860 1105 3308
Passcode: 321734