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A note on the center of mass in non-commutative theories

Robert C. Helling
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Abstract

The dynamics of a stack of N D-branes is described by U(N) gauge theory of which the central U(1) describes the center of mass motion and the remaining SU(N) describes the internal dynamics. In the non-commutative situation, these two parts are coupled by the *-commutator interaction. We describe here how to identify the correct decoupled U(1) center of mass subsector of U(N) gauge theory for the case of the non-commutative torus. The internal dynamics remainder is not a theory of SU(N) valued fields but has a simple description in momentum space.

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Robert C. Helling. 2005-04-26. A note on the center of mass in non-commutative theories. https://arxiv.org/abs/hep-th/0503104

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