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arXiv · 1312.7518

Dynamics of Polymers: a Mean-Field Theory

Glenn H. Fredrickson·Henri Orland
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Abstract

We derive a general mean-field theory of inhomogeneous polymer dynamics; a theory whose form has been speculated and widely applied, but not heretofore derived. Our approach involves a functional integral representation of a Martin-Siggia-Rose type description of the exact many-chain dynamics. A saddle point approximation to the generating functional, involving conditions where the MSR action is stationary with respect to a collective density field $ρ$ and a conjugate MSR response field $ϕ$, produces the desired dynamical mean-field theory. Besides clarifying the proper structure of mean-field theory out of equilibrium, our results have implications for numerical studies of polymer dynamics involving hybrid particle-field simulation techniques such as the single-chain in mean-field method (SCMF).

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Glenn H. Fredrickson, Henri Orland. 2013-12-29. Dynamics of Polymers: a Mean-Field Theory. https://doi.org/10.1063/1.4865911

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