High Energy Physics - Theory
[2203.02852] CFT duals of three-dimensional de Sitter gravity
https://arxiv.org/abs/2203.02852
Yasuaki Hikida, Tatsuma Nishioka, Tadashi Takayanagi, Yusuke Taki
We present a class of dS/CFT correspondence between two-dimensional CFTs and three-dimensional de Sitter spaces. We argue that such a CFT includes an SU(2) WZW model in the critical level limit k→−2, which corresponds to the classical gravity limit. We can generalize this dS/CFT by considering the SU(N) WZW model in the critical level limit k→−N, dual to the higher-spin gravity on a three-dimensional de Sitter space. We confirm that under this proposed duality the classical partition function in the gravity side can be reproduced from CFT calculations. We also point out a duality relation known in higher-spin holography provides further evidence. Moreover, we analyze two-point functions and entanglement entropy in our dS/CFT correspondence. Possible spectrum and quantum corrections in the gravity theory are discussed.
[2306.00090] The Källén-Lehmann representation in de Sitter spacetime
https://arxiv.org/abs/2306.00090
Manuel Loparco, Joao Penedones, Kamran Salehi Vaziri, Zimo Sun
We study two-point functions of symmetric traceless local operators in the bulk of de Sitter spacetime. We derive the Källén-Lehmann spectral decomposition for any spin and show that unitarity implies its spectral densities are nonnegative. In addition, we recover the Källén-Lehmann decomposition in Minkowski space by taking the flat space limit. Using harmonic analysis and the Wick rotation to Euclidean Anti de Sitter, we derive an inversion formula to compute the spectral densities. Using the inversion formula, we relate the analytic structure of the spectral densities to the late-time boundary operator content. We apply our technical tools to study two-point functions of composite operators in free and weakly coupled theories. In the weakly coupled case, we show how the Källén-Lehmann decomposition is useful to find the anomalous dimensions of the late-time boundary operators. We also derive the Källén-Lehmann representation of two-point functions of spinning primary operators of a Conformal Field Theory on de Sitter.
[2203.04947] Trouble in Paradox
https://arxiv.org/abs/2203.04947
Emil J. Martinec
Recent developments in holography have suggested a potential resolution to the black hole information paradox within the context of gravitational effective field theory. We emphasize the non-local nature of this proposed resolution, and highlight the ways in which observations outside the black hole can detect it and conclude that the black hole is not radiating like an ordinary body would.
General Relativity and Quantum Cosmology
[2306.12488] Light bending near non-asymptotically flat black holes
https://arxiv.org/abs/2306.12488
Flavio C. Sánchez, Armando A. Roque, Benito Rodríguez, Javier Chagoya
The gravitational deflection of light is a crucial test for modified gravity. A few years ago, Gibbons and Werner introduced a definition of the deflection angle based on the Gauss-Bonnet theorem. A related idea was proposed by Arakida for defining the deflection angle in non-asymptotically flat spacetimes We revisit this idea in the Kottler geometry and in a non-asymptotically flat solution to Horndeski gravity. Our analytic and numerical calculations show that a triangular array of laser beams can be designed so that the proposed definition of deflection angle is sensitive to a cosmological constant, whose contribution is amplified by the black hole mass. Moreover, we find that near the photon sphere, the deflection angle in the Horndeski solution is similar to its Schwarzschild counterpart, and we confirm that the shadows seen by a static observer would be identical. Our results offer insights that could be useful for designing future theoretical or experimental investigations aimed to detect sources of curvature in the universe.
Mathematical Physics
[2211.07064] Wilson Area Law formula on $\mathbb{R}^4$
https://arxiv.org/abs/2211.07064
Adrian P.C. Lim
