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arXiv · 2205.08726

Positivity of discrete information for CHL black holes

Suresh Govindarajan·Sutapa Samanta·P Shanmugapriya·Amitabh Virmani
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Abstract

Black holes carry more information about the microstates than just the total degeneracy. As a concrete example, the Z(N)-twined helicity trace indices for 1/4-BPS black holes of the CHL models allow extracting information about the distribution of the Z(N) charges among the black hole microstates. The number of black hole microstates carrying a definite eigenvalue under the generator of the Z(N) twining group must be positive. This leads to a specific prediction for the signs of certain linear combinations of Fourier coefficients of Siegel modular forms. We explicitly test these predictions for low charges. In the D1-D5-P duality frame, we compute the appropriate hair removed partition functions and show the positivity of the appropriate Fourier coefficients for low charges. We present various consistency checks on our computations.

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Suresh Govindarajan, Sutapa Samanta, P Shanmugapriya, Amitabh Virmani. 2022-05-18. Positivity of discrete information for CHL black holes. https://doi.org/10.1016/j.nuclphysb.2023.116095

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