Momentum scale expansion of sharp cutoff flow equations |
| |
| Institution: | 1. Department of Physics, Sophia University, Tokyo 102-8554, Japan;2. Department of Physics, the University of Tokyo 113-0033, Japan;3. Theoretical Research Division, Nishina Center, Riken, Wako 351-0198, Japan;1. Department of Physics, Sophia University, Tokyo 102-8554, Japan;2. Department of Physics, the University of Tokyo 113-0033, Japan;1. Abdus Salam International Centre for Theoretical Physics, Trieste, Italy;2. Donostia International Physics Center (DIPC), Paseo Manuel de Lardizábal, No. 4, 20018 Donostia, San Sebastián, Spain;3. Department of Physics, University of Antwerp, Antwerp, Belgium;4. Oxford University, Oxford, England, United Kingdom |
| |
| Abstract: | We show how the exact renormalization group for the effective action with a sharp momentum cutoff, may be organized by expanding one-particle irreducible parts in terms of homogeneous functions of momenta of integer degree (Taylor expansions not being possible). A systematic series of approximations - the O(pM) approximations - result from discarding from these parts, all terms of higher than the Mth degree. These approximations preserve a field reparametrization invariance, ensuring that the field's anomalous dimension is unambiguously determined. The lowest order approximation coincides with the local potential approximation to the Wegner-Houghton equations. We discuss the practical difficulties with extending the approximation beyond O(p0). |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
