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arXiv · 1504.02152

The geometry of generalized force matching in coarse-graining and related information metrics

Evangelia Kalligiannaki·Vagelis Harmandaris·Markos A. Katsoulakis·Petr Plechac
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Abstract

Using the probabilistic language of conditional expectations we reformulate the force matching method for coarse-graining of molecular systems as a projection on spaces of coarse observables. A practical outcome of this probabilistic description is the link of the force matching method with thermodynamic integration. This connection provides a way to systematically construct a local mean force in order to optimally approximate the potential of mean force through force matching. We introduce a generalized force matching condition for the local mean force in the sense that allows the approximation of the potential of mean force under both linear and non-linear coarse graining mappings (e.g., reaction coordinates, end-to-end length of chains). Furthermore, we study the equivalence of force matching with relative entropy minimization which we derive for general non-linear coarse graining maps. We present in detail the generalized force matching condition through applications to specific examples in molecular systems.

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Evangelia Kalligiannaki, Vagelis Harmandaris, Markos A. Katsoulakis, Petr Plechac. 2015-04-08. The geometry of generalized force matching in coarse-graining and related information metrics. https://arxiv.org/abs/1504.02152

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