301 citations · 2.5k across the 60 of their papers we have counts for
63 papers
Signal communication and modular theory
Roberto Longo
We propose a conceptual frame to interpret the prolate differential operator, which appears in Communication Theory, as an entropy operator; indeed, we write its expectation values…
An Algebra of Observables for de Sitter Space
Venkatesa Chandrasekaran, Roberto Longo, Geoff Penington +1
We describe an algebra of observables for a static patch in de Sitter space, with operators gravitationally dressed to the worldline of an observer. The algebra is a von Neumann al…
Causal Lie products of free fields and the emergence of quantum field theory
Detlev Buchholz, Roberto Longo, Karl-Henning Rehren
All causal Lie products of solutions of the Klein-Gordon equation and the wave equation in Minkowski space are determined. The results shed light on the origin of the algebraic str…
A note on continuous entropy
Roberto Longo, Edward Witten
Von Neumann entropy has a natural extension to the case of an arbitrary semifinite von Neumann algebra, as was considered by I. E. Segal. We relate this entropy to the relative ent…
Modular structure of the Weyl algebra
Roberto Longo
We study the modular Hamiltonian associated with a Gaussian state on the Weyl algebra. We obtain necessary/sufficient criteria for the local equivalence of Gaussian states, indepen…
Relative entropy and curved spacetimes
Fabio Ciolli, Roberto Longo, Alessio Ranallo +1
Given any half-sided modular inclusion of standard subspaces, we show that the entropy function associated with the decreasing one-parameter family of translated standard subspaces…