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arXiv · 1507.00987

SU(2|1) mechanics and harmonic superspace

E. Ivanov·S. Sidorov
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Abstract

We define the worldline harmonic SU(2|1) superspace and its analytic subspace as a deformation of the flat N=4, d=1 harmonic superspace. The harmonic superfield description of the two mutually mirror off-shell (4,4,0) SU(2|1) supermultiplets is developed and the corresponding invariant actions are presented, as well as the relevant classical and quantum supercharges. Whereas the σ-model actions exist for both types of the (4,4,0) multiplet, the invariant Wess-Zumino term can be defined only for one of them, thus demonstrating non-equivalence of these multiplets in the SU(2|1) case as opposed to the flat N=4, d=1 supersymmetry. A superconformal subclass of general SU(2|1) actions invariant under the trigonometric-type realizations of the supergroup D(2,1;α) is singled out. The superconformal Wess-Zumino actions possess an infinite-dimensional supersymmetry forming the centerless N=4 super Virasoro algebra. We solve a few simple instructive examples of the SU(2|1) supersymmetric quantum mechanics of the (4,4,0) multiplets and reveal the SU(2|1) representation contents of the corresponding sets of the quantum states.

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E. Ivanov, S. Sidorov. 2015-08-25. SU(2|1) mechanics and harmonic superspace. https://doi.org/10.1088/0264-9381%2F33%2F5%2F055001

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