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Exact closure and solution for spatial correlations in single-file diffusion.

ABSTRACT: In single-file transport particles diffuse in narrow channels while not overtaking each other. it is a fundamental model for the tracer subdiffusion observed in confined systems, such as zeolites or carbon nanotubes. This anomalous behavior originates from strong bath-tracer correlations in one dimension. Despite extensive effort, these remained elusive, because they involve an infinite hierarchy of equations. For the symmetric exclusion process, a paradigmatic model of single-file diffusion, we break the hierarchy to unveil and solve a closed exact equation satisfied by these correlations. Beyond quantifying the correlations, the role of this key equation as a tool for interacting particle systems is further demonstrated by its application to out-of-equilibrium situations, other observables, and other representative single-file systems.

SUBMITTER: Grabsch A

PROVIDER: S-EPMC8956262 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Exact closure and solution for spatial correlations in single-file diffusion.

Grabsch Aurélien A Poncet Alexis A Rizkallah Pierre P Illien Pierre P Bénichou Olivier O

Science advances 20220325 12

In single-file transport particles diffuse in narrow channels while not overtaking each other. it is a fundamental model for the tracer subdiffusion observed in confined systems, such as zeolites or carbon nanotubes. This anomalous behavior originates from strong bath-tracer correlations in one dimension. Despite extensive effort, these remained elusive, because they involve an infinite hierarchy of equations. For the symmetric exclusion process, a paradigmatic model of single-file diffusion, we ...[more]

PMID: 35333581

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