Virasoro conformal blocks in closed form

Eric Perlmutter

doi:10.1007/jhep08(2015)088

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arXiv · 1502.07742

Virasoro conformal blocks in closed form

Eric Perlmutter

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Abstract

Virasoro conformal blocks are fixed in principle by symmetry, but a closed-form expression is unknown in the general case. In this work, we provide three closed-form expansions for the four-point Virasoro blocks on the sphere, for arbitrary operator dimensions and central charge $c$. We do so by solving known recursion relations. One representation is a sum over hypergeometric global blocks, whose coefficients we provide at arbitrary level. Another is a sum over semiclassical Virasoro blocks obtained in the limit in which two external operator dimensions scale linearly with large $c$. In both cases, the $1/c$ expansion of the Virasoro blocks is easily extracted. We discuss applications of these expansions to entanglement and thermality in conformal field theories and particle scattering in three-dimensional quantum gravity.

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Eric Perlmutter. 2015-02-26. Virasoro conformal blocks in closed form. https://doi.org/10.1007/jhep08(2015)088

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