8 papers
Global wave parametrices on globally hyperbolic spacetimes
Matteo Capoferri, Claudio Dappiaggi, Nicolò Drago
In a recent work the first named author, Levitin and Vassiliev have constructed the wave propagator on a closed Riemannian manifold as a single oscillatory integral global both…
An operational construction of the sum of two non-commuting observables in quantum theory and related constructions
Nicolò Drago, Sonia Mazzucchi, Valter Moretti
The existence of a real linear-space structure on the set of observables of a quantum system -- i.e., the requirement that the linear combination of two generally non-commuting obs…
On Maxwell's Equations on Globally Hyperbolic Spacetimes with Timelike Boundary
Claudio Dappiaggi, Nicolò Drago, Rubens Longhi
We study Maxwell's equation as a theory for smooth -forms on globally hyperbolic spacetimes with timelike boundary as defined by Aké, Flores and Sanchez. In particular we start…
Equilibrium states in Thermal Field Theory and in Algebraic Quantum Field Theory
João Braga de Góes Vasconcellos, Nicolò Drago, Nicola Pinamonti
In this paper we compare the construction of equilibrium states at finite temperature for self-interacting massive scalar quantum field theories on Minkowski spacetime proposed by…
The notion of observable and the moment problem for *-algebras and their GNS representations
Nicolò Drago, Valter Moretti
We address some usually overlooked issues concerning the use of -algebras in quantum theory and their physical interpretation. If is a -algebra describing a qu…
The algebra of Wick polynomials of a scalar field on a Riemannian manifold
Claudio Dappiaggi, Nicolò Drago, Paolo Rinaldi
On a connected, oriented, smooth Riemannian manifold without boundary we consider a real scalar field whose dynamics is ruled by , a second order elliptic partial differential o…