2024/12/04 by Geoff Penington, Penington, Geoff, Pratik Rath +1 · 1 citation
Engineering · Mathematics · #Elasticity and Material Modeling #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Theory (hep-th) #Mathematical Approximation and Integration #Numerical methods in inverse problems #Quantum Physics (quant-ph)
paper · pdf · doi:10.48550/arxiv.2412.03670
openalex publication_date 2024/12/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
Recently Dong, Rath and Kudler-Flam proposed a modified cosmic brane prescription for computing the Rényi entropy Sα of a holographic system in the presence of multiple extremal surfaces. This prescription was found by assuming a diagonal approximation, where the Rényi entropy is computed after first measuring the areas of all extremal surfaces. We derive this diagonal approximation and show that it accurately computes Rényi entropies up to O(log G) corrections. For α<1, this allows us to derive the modified cosmic brane prescription, which differs from the original cosmic brane prescription at leading order in G. For α>1, it leads to the original cosmic brane prescription without needing to assume that replica symmetry is unbroken in the bulk.