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arXiv · 2005.06476

Achronal averaged null energy condition for extremal horizons and (A)dS

Felipe Rosso
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Abstract

We prove the achronal averaged null energy condition for general quantum field theories in the near horizon geometry of spherical extremal black holes (i.e. ${{\rm AdS}_2\times S^{d-2}}$), de Sitter and anti-de Sitter. The derivation follows from monotonicity of relative entropy after computing the modular hamiltonian of a null deformed region. For incomplete (but maximally extended) achronal null geodesics in ${\rm AdS}_2\times S^{d-2}$, we prove the positivity of a different light-ray operator for arbitrary CFTs. This agrees with a constraint recently derived for the Lorentzian cylinder.

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Felipe Rosso. 2020-05-13. Achronal averaged null energy condition for extremal horizons and (A)dS. https://doi.org/10.1007/jhep07(2020)023

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