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arXiv · hep-th/9901074

Chiral lagrangians and the QCD string

J. Alfaro·A. Dobado·D. Espriu
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Abstract

We propose a method to derive the low-energy efective action of QCD assuming that the long-distance properties of strong interactions can be described by a string theory. We bypass the usual problems related to the existence of the tachyon and absence of the adequate Adler zero by using a sigma model approach where excitations above the correct (chirally non-invariant) QCD vacuum are included. Two-dimensional conformal invariance then implies the vanishing of the O(p^4) effective lagrangian coefficients. We discuss ways to go beyond this limit.

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J. Alfaro, A. Dobado, D. Espriu. 1999-06-21. Chiral lagrangians and the QCD string. https://doi.org/10.1016/s0370-2693(99)00809-6

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