English

Softly Broken MQCD and the Theta Angle

High Energy Physics - Theory 2009-10-30 v2

Abstract

We consider a family of non-supersymmetric MQCD five-brane configurations introduced by Witten, and discuss the dependence of the curves on the microscopic theta angle and its relation with CP. We find evidence for a non-trivial spectral flow of the curves (vacua) and for the level-crossing of adjacent curves at a particular value of the theta angle, with spontaneous breaking of CP symmetry, providing an MQCD analogue of the phase transitions in theta proposed by 't Hooft.

Cite

@article{arxiv.hep-th/9711030,
  title  = {Softly Broken MQCD and the Theta Angle},
  author = {J. L. F. Barbon and A. Pasquinucci},
  journal= {arXiv preprint arXiv:hep-th/9711030},
  year   = {2009}
}

Comments

12 pages, references added. Version published in Phys. Lett. B

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