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Instability of Non-Commutative SYM Theories at Finite Temperature

Karl Landsteiner·Esperanza Lopez·Michel H. G. Tytgat
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Abstract

We extend our previous work on the quasi-particle excitations in N=4 non-commutative U(1) Yang-Mills theory at finite temperature. We show that above some critical temperature there is a tachyon in the spectrum of excitations. It is a collective transverse photon mode polarized in the non-commutative plane. Thus the theory seems to undergo a phase transition at high temperature. Furthermore we find that the group velocity of quasi-particles generically exceeds the speed of light at low momentum.

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Karl Landsteiner, Esperanza Lopez, Michel H. G. Tytgat. 2001-08-02. Instability of Non-Commutative SYM Theories at Finite Temperature. https://doi.org/10.1088/1126-6708%2F2001%2F06%2F055

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