Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
1997-06-04
Annals Phys. 263 (1998) 214-237
Physics
High Energy Physics
High Energy Physics - Phenomenology
26 pages TeX, uses mtexsis.tex
Scientific paper
10.1006/aphy.1997.5765
We consider the possibility that QCD with N flavors has a useful low-energy description with 2N flavors. Specifically, we investigate a free theory of 2N quarks. Although the free theory is U(N)_L X U(N)_R invariant, it admits a larger U(2N) invariance. However, when the axial anomaly is accounted for in the effective theory by a 't Hooft interaction, only SU(N)_L X SU(N)_R X U(1)_B \subset U(2N) survives. There is however a residual discrete symmetry that is not a symmetry of the QCD lagrangian. This S_2 subgroup of U(2N) has many interesting properties. For instance, when explicit chiral symmetry breaking effects are present, S_2 is broken unless \bar\theta=0 or pi. By expressing the free theory on the light-front, we show that flavor doubling implies several superconvergence relations in pion-hadron scattering. Implicit in the 2N-flavor effective theory is a Regge trajectory with vacuum quantum numbers and unit intercept whose behavior is constrained by S_2. In particular, S_2 implies that forward pion-hadron scattering becomes purely elastic at high-energies, in good agreement with experiment.
No associations
LandOfFree
Flavor Doubling and the Nature of Asymptopia does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Flavor Doubling and the Nature of Asymptopia, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Flavor Doubling and the Nature of Asymptopia will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-552695