Eur. Phys. J. C (2007) 49: 997-1010
https://doi.org/10.1140/epjc/s10052-006-0178-2

Regular Article - Theoretical Physics

Do instantons like a colorful background?

¹ Institut fuer Theoretische Physik, Philosophenweg 16, 69120, Heidelberg, Germany
² Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607, Hamburg, Germany

^* e-mail: jjaeckel@mail.desy.de

Received: 20 September 2006
Published online: 19 January 2007

Abstract

We investigate chiral symmetry breaking and color symmetry breaking in QCD. The effective potential of the corresponding scalar condensates is discussed in the presence of non-perturbative contributions from the semiclassical one-instanton sector. We concentrate on a color singlet scalar background which can describe chiral condensation, as well as a color octet scalar background which can generate mass for the gluons. Whereas a non-vanishing singlet chiral field is favored by the instantons, we have found no indication for a preference of color octet backgrounds.