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arXiv · 1407.8256

Noise-induced multistability in chemical systems: Discrete vs Continuum modeling

Andrew Duncan·Shuohao Liao·Tomas Vejchodsky·Radek Erban·Ramon Grima
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Abstract

The noisy dynamics of chemical systems is commonly studied using either the chemical master equation (CME) or the chemical Fokker-Planck equation (CFPE). The latter is a continuum approximation of the discrete CME approach. We here show that the CFPE may fail to capture the CME's prediction of noise-induced multistability. In particular we find a simple chemical system for which the CME's marginal probability distribution changes from unimodal to multimodal as the system-size decreases below a critical value, while the CFPE's marginal probability distribution is unimodal for all physically meaningful system sizes.

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Andrew Duncan, Shuohao Liao, Tomas Vejchodsky, Radek Erban, Ramon Grima. 2014-07-31. Noise-induced multistability in chemical systems: Discrete vs Continuum modeling. https://doi.org/10.1103/physreve.91.042111

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