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arXiv · 1710.05788

Continuous-spin field propagator and interaction with matter

Xavier Bekaert·Jihad Mourad·Mojtaba Najafizadeh
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Abstract

Action principles for the single and double valued continuous-spin representations of the Poincare group have been recently proposed in a Segal-like formulation. We address three related issues: First, we explain how to obtain these actions directly from the Fronsdal-like and Fang-Fronsdal-like equations by solving the traceless constraints in Fourier space. Second, we introduce a current, similar to the one of Berends, Burgers and Van Dam, which is bilinear in a pair of scalar matter fields, to which the bosonic continuous-spin field can couple minimally. Third, we investigate the current exchange mediated by a continuous-spin particle obtained from this action principle and investigate whether it propagates the right degrees of freedom, and whether it reproduces the known result for massless higher-spin fields in the helicity limit.

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Xavier Bekaert, Jihad Mourad, Mojtaba Najafizadeh. 2017-10-16. Continuous-spin field propagator and interaction with matter. https://doi.org/10.1007/jhep11(2017)113

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