Calculating field theories beyond the mean-field level

Autor:	Stephan A. Baeurle, E. A. Nogovitsin, G. V. Efimov
Rok vydání:	2006
Předmět:	Physics symbols.namesake Field (physics) Mean field theory Gaussian Polymer solution symbols General Physics and Astronomy Statistical physics Representation (mathematics) Energy (signal processing)
Zdroj:	Europhysics Letters (EPL). 75:378-384
ISSN:	1286-4854 0295-5075
DOI:	10.1209/epl/i2006-10133-6
Popis:	Mean-field theories are widely used as comparative theoretical tools throughout all areas of natural and engineering sciences. They are capable in many instances to deliver useful insights in properties and behavior of multi-body systems at relatively moderate computational costs. However, there are a multitude of cases were the mean-field approach has been found to provide either inaccurate or even qualitatively wrong results. In this article we present a new low-cost approach based on the method of Gaussian equivalent representation of Efimov and Ganbold, and show that it provides a far more accurate 0th-order approximation of the free energy and related thermodynamic and structural quantities than the mean-field approach. We demonstrate its effectiveness on the example of a polymer solution model in the dilute and semi-dilute regime.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::fcc2344931378c10b28c7ecd90b40f76 https://doi.org/10.1209/epl/i2006-10133-6 Zobrazit plný text záznamu