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On Singleton Composites in Non-compact WZW Models

J. Engquist·P. Sundell·L. Tamassia
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Abstract

We examine the so(2,D-1) WZW model at the subcritical level -(D-3)/2. It has a singular vacuum vector at Virasoro level 2. Its decoupling constitutes an affine extension of the equation of motion of the (D+1)-dimensional conformal particle, i.e. the scalar singleton. The admissible (spectrally flowed) representations contain the singleton and its direct products, consisting of massless and massive particles in AdS_D. In D=4 there exists an extended model containing both scalar and spinor singletons of sp(4). Its realization in terms of 4 symplectic-real bosons contains the spinor-oscillator constructions of the 4D singletons and their composites. We also comment on the prospects of relating gauged versions of the models to the phase-space quantization of partonic branes and higher-spin gauge theory.

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J. Engquist, P. Sundell, L. Tamassia. 2007-02-01. On Singleton Composites in Non-compact WZW Models. https://doi.org/10.1088/1126-6708%2F2007%2F02%2F097

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