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Resolution of the strong CP and U(1) problems

H. Banerjee
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Abstract

Definition of the determinant of Euclidean Dirac operator in the nontrivial sector of gauge fields suffers from an inherent ambiguity. The popular Osterwalder-Schrader (OS) recipe for the conjugate Dirac field leads to the option of a vanishing determinant. We propose a novel representation for the conjugate field which depends linearly on the Dirac field and yields a nonvanishing determinant in the nontrivial sector. Physics, it appears, chooses this second option becuase the novel representation leads to a satisfactory resolution of two outstanding problems, the strong CP and U(1) problems, attributed to instanton effects.

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H. Banerjee. 1995-08-14. Resolution of the strong CP and U(1) problems. https://arxiv.org/abs/hep-th/9508065

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