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arXiv · hep-ph/0511081

Parity Doubling and SU(2)_L x SU(2)_R Restoration in the Hadron Spectrum

Robert L. Jaffe·Dan Pirjol·Antonello Scardicchio
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Abstract

We construct the most general nonlinear representation of chiral SU(2)_L x SU(2)_R broken down spontaneously to the isospin SU(2), on a pair of hadrons of same spin and isospin and opposite parity. We show that any such representation is equivalent, through a hadron field transformation, to two irreducible representations on two hadrons of opposite parity with different masses and axial couplings. This implies that chiral symmetry realized in the Nambu-Goldstone mode does not predict the existence of degenerate multiplets of hadrons of opposite parity nor any relations between their couplings or masses.

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Robert L. Jaffe, Dan Pirjol, Antonello Scardicchio. 2006-06-02. Parity Doubling and SU(2)_L x SU(2)_R Restoration in the Hadron Spectrum. https://doi.org/10.1103/physrevlett.96.121601

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