Baryon currents in QCD with compact dimensions

B. Lucini, A. Patella and C. Pica a Physics Department, Swansea University, Singleton Park, Swansea SA2 8PP, UK b Scuola Normale Superiore, Piazza dei Cavalieri 27, 56126 Pisa, Italy c INFN Pisa, Largo B. Pontecorvo 3 Ed. C, 56127 Pisa, Italy d Physics Department, Brookhaven National Laboratory, Upton, NY 11973, USA Abstract On a compact space with non-trivial cycles, for sufficiently small values of the radii of the compact dimensions, SU(N) gauge theories coupled with fermions in the fundamental representation spontaneously break charge conjugation, time reversal and parity. We show at one loop in perturbation theory that a physical signature for this phenomenon is a non-zero baryonic current wrapping around the compact directions. The persistence of this current beyond the perturbative regime is checked by lattice simulations.