Optimized renormalization group flows - art. no. 105007

Authors
Citation
Df. Litim, Optimized renormalization group flows - art. no. 105007, PHYS REV D, 6410(10), 2001, pp. 5007
Citations number
42
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW D
ISSN journal
0556-2821 → ACNP
Volume
6410
Issue
10
Year of publication
2001
Database
ISI
SICI code
0556-2821(20011115)6410:10<5007:ORGF-A>2.0.ZU;2-W
Abstract
We study the optimization of exact renormalization group (ERG) flows. We ex plain why the convergence of approximate solutions towards the physical the ory is optimized by appropriate choices of the regularization. We consider specific optimized regulators for bosonic and fermionic fields and compare the optimized ERG flows with generic ones. This is done up to second order in the derivative expansion at both vanishing and nonvanishing temperature. We find that optimized flows at finite temperature factorize. This corresp onds to the disentangling of thermal and quantum fluctuations. A similar fa ctorization is found at second order in the derivative expansion. The corre sponding optimized flow for a "proper-time renormalization group" is also p rovided to leading order in the derivative expansion.