Chiral Symmetry in the String Representation of the Large N QCD
نویسنده
چکیده
We use the worldline representation of the one loop fermionic effective action to obtain the vertex functions that describe mesons in a possible string representation of the large N QCD. These vertex functions are then applied to study the chiral limit of the theory. We find that the propagator constructed from the vertex function V0, which would describes a tachyon in the open Nambu-Goto bosonic string theory, behaves in two distinct manner depending on how the chiral symmetry is realized. V0 itself does not correspond to any physical state of the theory but appears as a part of the vertex function for the sigma. When the chiral symmetry is spontaneously broken V0 describes a massless ghost state which insures that the sigma is massive and is no longer degenerate with the pion. We also emphasize the need for the boundary fermions in the string representation of mesons. ∗Associate, Abdus Salam International Center for Theoretical Physics, Trieste, Italy.
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