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Department of Mathematics,
University of California San Diego

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Quantum Information & Computation

Tomasz Placek

Institute of Philosophy of the Jagiellonian University

On transitions in branching histories

Abstract:

Branching-style models were proposed in the 1960's as a logician's tool to study combinations of tenses and modalities, as in ``it is still possible that it will rain in SD tomorrow'' but ``it is already settled that last Summer was hot in SD''. A current theory of Branching Space-Times (BST), put forward by N.~Belnap in 1992, is an axiomatic framework that aims to describe how indeterminism plays out in a spatio-temporal world. To this end it postulates a set of relativistic space-times, any two of which are pasted together in some particular region. Although a BST structure is continuous, it is possible to discretise it, by focusing on particular objects, known as transitions, and interpreted as places at which chancy actions happen. A discretised structure, defined as a partially ordered set of transitions, recovers then much, but not all information about the initial structure. As these ideas are reminiscent of the Causal Set Program, I will end up the talk by discussing some connections between the two frameworks.

Host: David Meyer

November 29, 2018

9:00 AM

AP&M 7218

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