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arXiv · 2212.00078

How to derive a predictive active field theory: a step-by-step tutorial

Michael te Vrugt·Jens Bickmann·Raphael Wittkowski
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Abstract

The study of active soft matter has developed into one of the most rapidly growing areas of physics. Field theories, which can be developed either via phenomenological considerations or by coarse-graining of a microscopic model, are a very useful tool for understanding active systems. Here, we provide a detailed review of a particular coarse-graining procedure, the interaction-expansion method (IEM). The IEM allows for the systematic microscopic derivation of predictive field theories for systems of interacting active particles. We explain in detail how it can be used for a microscopic derivation of active model B+, which is a widely used scalar active matter model. Extensions and possible future applications are also discussed.

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cond-mat.softcond-mat.mtrl-scicond-mat.stat-mechphysics.chem-ph

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Michael te Vrugt, Jens Bickmann, Raphael Wittkowski. 2022-11-30. How to derive a predictive active field theory: a step-by-step tutorial. https://arxiv.org/abs/2212.00078

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