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Hydrodynamic Limit for the SSEP with a Slow Membrane

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In this paper we consider a symmetric simple exclusion process on the d-dimensional discrete torus TNd{\mathbb {T}}^d_N with a spatial non-homogeneity given by a slow membrane. The slow membrane is defined here as the boundary of a smooth simple connected region Λ\Lambda on the continuous d-dimensional torus Td{\mathbb {T}}^d. In this setting, bonds crossing the membrane have jump rate α/Nβ\alpha /N^\beta and all other bonds have jump rate one, where α>0\alpha >0, β[0,]\beta \in [0,\infty ], and NNN\in {\mathbb {N}} is the scaling parameter. In the diffusive scaling we prove that the hydrodynamic limit presents a dynamical phase transition, that is, it depends on the regime of β\beta . For β[0,1)\beta \in [0,1), the hydrodynamic equation is given by the usual heat equation on the continuous torus, meaning that the slow membrane has no effect in the limit. For β(1,]\beta \in (1,\infty ], the hydrodynamic equation is the heat equation with Neumann boundary conditions, meaning that the slow membrane Λ\partial \Lambda divides Td{\mathbb {T}}^d into two isolated regions Λ\Lambda and Λ\Lambda ^\complement . And for the critical value β=1\beta =1, the hydrodynamic equation is the heat equation with certain Robin boundary conditions related to the Fick’s Law.
The region in gray represents Λ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\Lambda $$\end{document}, and the white region represents its complement Λ∁\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\Lambda ^\complement $$\end{document}. The grid represents N-1TNd\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$N^{-1}{\mathbb {T}}_N^d$$\end{document}, the discrete torus embedded on the continuous torus Td\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathbb {T}}^d$$\end{document}. By ζ→(u)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\vec {\zeta }(u)$$\end{document} we denote the normal exterior unitary vector to Λ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\Lambda $$\end{document} at the point u∈∂Λ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$u\in \partial \Lambda $$\end{document}
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Journal of Statistical Physics (2019) 175:233–268
https://doi.org/10.1007/s10955-019-02254-y
Hydrodynamic Limit for the SSEP with a Slow Membrane
Tertuliano Franco1·Mariana Tavares1
Received: 21 September 2018 / Accepted: 16 February 2019 / Published online: 21 February 2019
© Springer Science+Business Media, LLC, part of Springer Nature 2019
Abstract
In this paper we consider a symmetric simple exclusion process on the d-dimensional discrete
torus Td
Nwith a spatial non-homogeneity given by a slow membrane. The slow membrane
is defined here as the boundary of a smooth simple connected region on the continuous
d-dimensional torus Td. In this setting, bonds crossing the membrane have jump rate α/Nβ
and all other bonds have jump rate one, where α>0, β∈[0,∞],andNNis the scaling
parameter. In the diffusive scaling we prove that the hydrodynamic limit presents a dynamical
phase transition, that is, it depends on the regime of β.Forβ∈[0,1), the hydrodynamic
equation is given by the usual heat equation on the continuous torus, meaning that the slow
membrane has no effect in the limit. For β(1,∞], the hydrodynamic equation is the heat
equation with Neumann boundary conditions, meaning that the slow membrane ∂ divides
Tdinto two isolated regions and . And for the critical value β=1, the hydrodynamic
equation is the heat equation with certain Robin boundary conditions related to the Fick’s
Law.
Keywords Hydrodynamic limit ·Exclusion process ·Non-homogeneous environment ·
Slow bonds
Mathematics Subject Classification 60K35 ·35K55
1 Introduction
A central question of Statistical Mechanics is about how microscopic interactions determine
the macroscopic behavior of a given system. Under this guideline, an entire area on scaling
limits of interacting random particle systems has been developed, see [10] and references
therein.
Communicated by Abhishek Dhar.
BTertuliano Franco
tertu@ufba.br
Mariana Tavares
tavaresaguiar57@gmail.com
1UFBA, Instituto de Matemática, Campus de Ondina, Av. Adhemar de Barros, S/N.,
Salvador CEP 40170-110, Brazil
123
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... The microscopic models they considered are either defined on a ring with a slow site/slow bond, or defined on a segment with slow boundaries. The results have also been extended to higher dimensions in [8,14,16]. ...
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... where the supremum is carried over all functionsH ∈ C 0,1 ([0, T ]×R d ) with compact support contained in [0, T ] × ([−M, M] d \{|u 1 | ≤ 1 M }). Based on the above lemma, the proof of Lemma 4.3 follows from the same analysis as that given in the proof of[8, Lemma 5.7], where a crucial step is the utilization of Riesz's representation theorem, the details of which we omit here. ...
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