Ambiguities in effective chiral models with cut-off

Abstract

Using an example, we demonstrate that predictions of effective chiral quark models with cut-off (Nambu-Jona-Lasino model, chiral soliton model with cut-off) for space nonuniform systems depend strongly on the specific choice of the regularization method. Such ambiguities preclude firm conclusions on the detailed role of the Dirac sea in such systems without a precise knowledge of form factors of the effective theory.