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arXiv · 1703.00769

General criterion for harmonicity

Karel Proesmans·Hans Vandebroek·Christian Van den Broeck
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Abstract

Inspired by Kubo-Anderson Markov processes, we introduce a new class of transfer matrices whose largest eigenvalue is determined by a simple explicit algebraic equation. Applications include the free energy calculation for various equilibrium systems and a general criterion for perfect harmonicity, i.e., a free energy that is exactly quadratic in the external field. As an illustration, we construct a "perfect spring", namely a polymer with non-Gaussian, exponentially distributed sub-units which nevertheless remains harmonic until it is fully stretched. This surprising discovery is confirmed by Monte Carlo and Langevin simulations.

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Karel Proesmans, Hans Vandebroek, Christian Van den Broeck. 2017-09-14. General criterion for harmonicity. https://doi.org/10.1103/physrevlett.119.147803

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