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arXiv · 1907.09155

Mapping TASEP back in time

Abstract

We obtain a new relation between the distributions $μ_t$ at different times $t\ge 0$ of the continuous-time TASEP (Totally Asymmetric Simple Exclusion Process) started from the step initial configuration. Namely, we present a continuous-time Markov process with local interactions and particle-dependent rates which maps the TASEP distributions $μ_t$ backwards in time. Under the backwards process, particles jump to the left, and the dynamics can be viewed as a version of the discrete-space Hammersley process. Combined with the forward TASEP evolution, this leads to a stationary Markov dynamics preserving $μ_t$ which in turn brings new identities for expectations with respect to $μ_t$. The construction of the backwards dynamics is based on Markov maps interchanging parameters of Schur processes, and is motivated by bijectivizations of the Yang-Baxter equation. We also present a number of corollaries, extensions, and open questions arising from our constructions.

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Leonid Petrov, Axel Saenz. 2021-02-17. Mapping TASEP back in time. https://arxiv.org/abs/1907.09155

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