1126-6708_2001_11_059.pdf (193.04 kB)
Derivative expansion and renormalization group flows
We study the convergence of the derivative expansion for flow equations. The convergence strongly depends on the choice for the infrared regularisation. Based on the structure of the flow, we explain why optimised regulators lead to better physical predictions. This is applied to O(N)-symmetric real scalar field theories in 3d, where critical exponents are computed for all N. In comparison to the sharp cut-off regulator, an optimised flow improves the leading order result up to 10%. An analogous reasoning is employed for a proper time renormalisation group. We compare our results with those obtained by other methods.
History
Publication status
- Published
File Version
- Published version
Journal
Journal of High Energy PhysicsISSN
1126-6708Publisher
Institute of PhysicsExternal DOI
Issue
11Page range
059Pages
15.0Department affiliated with
- Physics and Astronomy Publications
Full text available
- Yes
Peer reviewed?
- Yes