Multispecies inhomogeneous $t$-PushTASEP from antisymmetric fusion
Arvind Ayyer, Atsuo Kuniba
TL;DR
The paper delivers a Baxter-type construction for the inhomogeneous $n$-species $t$-PushTASEP by expressing the Markov generator as a signed derivative of a family of commuting transfer matrices built from antisymmetric representations of $U_t(\,\widehat{sl}_{n+1}\,)$. This framework relies on the antisymmetric fusion to construct $S^{k,1}(z)$ and the associated transfer matrices $T^k(z)$, whose alternating sum extracts the PushTASEP dynamics while canceling forbidden channels. In the homogeneous limit, PushTASEP and ASEP become sister models sharing eigenstates and stationary distributions, with a matrix-product state description for stationary probabilities tied to a Zamolodchikov–Faddeev algebra. The results illuminate a deep integrable structure for long-range multispecies stochastic processes and suggest avenues toward higher-dimensional formulations via three-dimensional integrability.
Abstract
We investigate the recently introduced inhomogeneous $n$-species $t$-PushTASEP, a long-range stochastic process on a periodic lattice. A Baxter-type formula is established, expressing the Markov matrix as an alternating sum of commuting transfer matrices over all the fundamental representations of $U_t(\widehat{sl}_{n+1})$. This superposition acts as an inclusion-exclusion principle, selectively extracting the sequential particle transitions characteristic of the PushTASEP, while canceling forbidden channels. The homogeneous specialization connects the PushTASEP to ASEP, showing that the two models share eigenstates and a common integrability structure.
