Reparameterisation invariance constraints on heavy particle effective field theories
Abstract
Since fields in the heavy quark effective theory are described by both a velocity and a residual momentum, there is redundancy in the theory: small shifts in velocity may be absorbed into a redefinition of the residual momentum. We demonstrate that this trivial reparameterisation invariance has non-trivial consequences: it relates coefficients of terms of different orders in the {1}/{m} expansion and requires linear combinations of these operators to be multiplicatively renormalised. For example, the operator {- 2}/{2m} in the effective lagrangian has zero anomalous dimension, coefficient one, and does not receive any non-perturbative contributions from matching conditions. We also demonstrate that this invariance severely restricts the forms of operators which may appear in chiral lagrangians for heavy particles.
- Publication:
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Physics Letters B
- Pub Date:
- July 1992
- DOI:
- 10.1016/0370-2693(92)91786-9
- arXiv:
- arXiv:hep-ph/9205228
- Bibcode:
- 1992PhLB..286..348L
- Keywords:
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- High Energy Physics - Phenomenology
- E-Print:
- (14 pages, 0 figures), UCSD/PTH 92-15