Diquarks in the instanton picture instanton picture

Abstract

We recall the 't Hooft-like many-quark interactions induced by instantons. By introducing auxiliary boson fields these interactions can be bosonized in two different ways, “standard” and “non-standard”. The “stadard” bosonization involving only scalar and pseudosalar meson fields in justified in the limit N _e → ∞ . We consider in some detail a special case of QCD with N _c = N _f =2 whose global symmetry is not U(2) _L x U(2) _R but actually U(4). The “standard” bosonization stresses the diquark degrees of freedom. The real world with N _c = N _f = 3 lies perhaps in between the imaginary worlds with N _c = N _f = 2 and N _c = ∞. Therefore, one would expect that the diquark degrees of freedom could play some role in the real world as well.