2019/07/19 by Dimitrios Katsinis, Georgios Pastras
Mathematics · Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Entropy (arrow of time) #Geometry #Inverse #Mathematical physics #Mathematics #Minkowski space #Mutual information #Physics #Quantum #Quantum entanglement #Quantum many-body systems #Quantum mechanics #Scalar (mathematics) #Scalar field #Statistics #hep-th #quant-ph
paper · pdf · doi:10.1007/jhep02(2020)091
published as JHEP 02 (2020) 091 · 66 pages (41 pages main text & 25 pages appendix), 7 figures
arxiv created 2019/07/19 · openalex created_date 2019/07/30 · openalex publication_date 2020/02/01 · arxiv updated 2020/04/20 · openalex updated_date 2026/08/05
A bstract We study the entanglement entropy and the mutual information in coupled harmonic systems at finite temperature. Interestingly, we find that the mutual information does not vanish at infinite temperature, but it rather reaches a specific finite value, which can be attributed to classical correlations solely. We further obtain high and low temperature expansions for both quantities. Then, we extend the analysis performed in the seminal paper by Srednicki [1] for free real scalar field theories in Minkowski space-time in 3 + 1 dimensions at a thermal state. We find that the mutual information obeys an area law, similar to that obeyed by the entanglement entropy at vanishing temperature. The coefficient of this area law does not vanish at infinite temperature. Then, we calculate this coefficient perturbatively in a 1 /μ expansion, where μ is the mass of the scalar field. Finally, we study the high and low temperature behaviour of the area law term.