Quantum Causal Graph Dynamics

Abstract

Suppose that an entire graph evolves quantum mechanically and gets driven into superpositions of graphs of different connectivities and node populations. Suppose moreover that the evolution is causal, meaning that information can only propagate at a bounded speed, with respect to graph distance. We show that this quantum evolution must decompose into small, local unitary rewritings of graph disks. This unifies a result on Quantum Cellular Automata with another on Reversible Causal Graph Dynamics. To reach the result we formalize a notion of causality which is valid in the context of quantum superpositions of time-varying graphs, and has a number of good properties.

References: 1, 2, 3

Date
Friday, February 11, 2022 15:00 Europe/Paris
Event
GReTA seminar
Zoom registration: click here! Please consider joining the meeting already within the 15min prior to the start of the seminar to ensure your setup is functioning properly. You may connect with either the Zoom web or Zoom desktop clients.

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Pablo Arrighi
Pablo Arrighi
Professor

Professor in the Informatics department of University of Paris-Saclay. Leader of the Quacs team (under the process of becoming an Inria Saclay team) of the LMF laboratory.