A variational real-space renormalisation-group transformation based on the cumulant expansion
- 1 January 1979
- journal article
- Published by IOP Publishing in Journal of Physics A: General Physics
- Vol. 12 (1) , 91-97
- https://doi.org/10.1088/0305-4470/12/1/021
Abstract
The first order cumulant expansion of Niemeijer and van Leeuwen (1974) is combined with a variational method to find the 'best' value of a fixed point Hamiltonian depending upon a parameter, p. A new method for calculating eigen values near this fixed point is proposed, based upon the neglect of terms proportional to the error neglected at the fixed point. This approach determines delta p/ delta K unambiguously. Calculations are carried out for a few simple models. The results are more accurate than those of most other comparably simple approaches.Keywords
This publication has 4 references indexed in Scilit:
- Potts model specific heat critical exponentsJournal of Physics A: General Physics, 1977
- Variational approximations for renormalization group transformationsJournal of Statistical Physics, 1976
- Wilson theory for 2-dimensional Ising spin systemsPhysica, 1974
- Potts model at the critical temperatureJournal of Physics C: Solid State Physics, 1973