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Velocity fluctuations of noisy reaction fronts propagating into a metastable state: testing theory in stochastic simulations

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 نشر من قبل Evgeniy Khain
 تاريخ النشر 2012
  مجال البحث فيزياء علم الأحياء
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The position of a reaction front, propagating into a metastable state, fluctuates because of the shot noise of reactions and diffusion. A recent theory [B. Meerson, P.V. Sasorov, and Y. Kaplan, Phys. Rev. E 84, 011147 (2011)] gave a closed analytic expression for the front diffusion coefficient in the weak noise limit. Here we test this theory in stochastic simulations involving reacting and diffusing particles on a one-dimensional lattice. We also investigate a small noise-induced systematic shift of the front velocity compared to the prediction from the spatially continuous deterministic reaction-diffusion equation.

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