Derivative expansions of renormaliztion group effective potentials for {phi}{sup 4} field theories
- Univ. of Colorado, CO (United States)
We approximate an exact Renormalization Group (RG) equation for the flow of the effective action of {phi}{sup 4} field theories by including next-to-leading order (NLO) terms in a derivative expansion. This level of approximation allows us to treat effects of wavefunction renormalization which are beyond the scope of the leading order (LO) formulation. We compare calculations based on a {open_quote}latticized {close_quotes} version of our RG equation in 3 Euclidean dimensions directly with Monte Carlo (MC) results and find excellent overall agreement as well as substantial improvement over LO calculations. We solve the continuum form of our equation to find the Wilson fixed point and determine the critical exponent {eta} (0.046). We also find the critical exponents {nu} (0.666) and {omega} (0.735). These latter two are in much improved agreement with {open_quote}world`s best{close_quotes} values com- pared to those obtained at LO (where no prediction for {eta} is possible). We also find that the {open_quote}universal potential{close_quote} determined via MC methods by Tsypin can be understood quantitatively using our NLO RG equations. Careful analysis shows that ambiguities which plague {open_quote}smooth cutoff{close_quotes} formulations do not arise with our RG equations.
- OSTI ID:
- 255614
- Report Number(s):
- CONF-9510116-; ISSN 0003-0503; TRN: 96:015929
- Journal Information:
- Bulletin of the American Physical Society, Vol. 40, Issue 10; Conference: Fall meeting of the Division of Nuclear Physics of the American Physical Society, Bloomington, IN (United States), 25-28 Oct 1995; Other Information: PBD: Oct 1995
- Country of Publication:
- United States
- Language:
- English
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