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arXiv · 2201.10540

Hydrodynamic behavior of long-range symmetric exclusion with a slow barrier: superdiffusive regime

Pedro Cardoso·Patrícia Gonçalves·Byron Jiménez-Oviedo
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Abstract

We analyse the hydrodynamical behavior of the long jumps symmetric exclusion process in the presence of a slow barrier. The jump rates are given by a symmetric transition probability $p(\cdot)$ with infinite variance. When jumps occur from $\mathbb{Z}_{-}^{*}$ to $\mathbb N$ the rates are slowed down by a factor $\alpha n^{-\beta}$ (with $\alpha>0$ and $\beta\geq 0$). We obtain several partial differential equations given in terms of the regional fractional Laplacian on $\mathbb R^*$ and with different boundary conditions. Surprisingly, in opposition to the diffusive regime, we get different regimes depending on whether $\alpha=1$ (all bonds with the same rate) or $\alpha\neq 1$.

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Pedro Cardoso, Patrícia Gonçalves, Byron Jiménez-Oviedo. 2022-01-25. Hydrodynamic behavior of long-range symmetric exclusion with a slow barrier: superdiffusive regime. https://arxiv.org/abs/2201.10540

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