arXiv subjects

F. Sobrero

Publications and source records attributed to F. Sobrero.

3 recordsLinked to original sources

arXiv2026

When Bob orbits Alice: entanglement harvesting in circular motion

We study radiative processes of two qubits coupled to a massless scalar field prepared in the Minkowski vacuum state. The analyze the effects of vacuum fluctuations in the generation of qubits' entangled states is performed. We assume one of the qubits is at rest in an inertial frame while the other comoves with a uniformly rotating frame, i.e., undergoing circular motion. We investigate how the entanglement harvesting phenomenon depends on the radius and angular velocity of the non-inertial qubit. We compute the concurrence and mutual information to identify the set of circular motion parameters that maximizes entanglement generation.

hep-th↗

arXiv2025

Hydrodynamic fields in fluctuating environment: a model for isochoric heat capacity of simple liquids

Using functional methods, we investigate the sound quanta arising from quantized hydrodynamic fields in simple liquids at low temperatures, under the influence of high-energy processes, coming from non-hydrodynamic degrees of freedom. To model these effects on the hydrodynamic fields, we assume that the quantum fields are coupled to an additive, delta-correlated (in space and time) quantum noise field. Thus, the hydrodynamic fields are defined in a fluctuating environment. After defining the generating functional of connected correlation functions in the presence of the noise field, we perform a functional integral over all noise field configurations. This is done using a formal object inspired by the distributional zeta-function method, called the configurational zeta-function. We obtain a new generating functional written in terms of an analytically tractable functional series. This formalism allow us to obtain the excitation spectra of liquids. In the liquid, each term of the series describes the emergent non-interacting elementary excitations with the usual phonon-like dispersion relation and additional excitations with dispersion relations with gaps in pseudo-momentum space. Finally, the behavior of the constant volume specific heat as a function of temperature is obtained for different simple liquids.

cond-mat.dis-nn↗

arXiv2025

Time-dependent accelerated Unruh-DeWitt detector without event horizon

We investigate unitarily inequivalent representations of the algebra of operators in quantum field theory in the cases where there is a Fock representation of the commutation relations. We examine more closely the operational definition of a measurement device, discussing the Unruh-DeWitt and Glauber models of quantum detectors. The transition probability per unit of proper time of both detectors in different non-inertial frames of reference in Minkowski spacetime is evaluated. We first study detectors traveling in a stationary worldline with a constant proper acceleration, i.e., a hyperbolic motion, interacting with the field prepared in the Poincar\'e invariant Fock vacuum state. Next, we study the Unruh-DeWitt detector at rest in a non-uniformly accelerated frame, with a time dependent acceleration interacting with the field in the Poincar\'e invariant Fock vacuum state. We evaluate the positive frequency Wightman function for the non-uniformly accelerated frame in a finite time interval and find that it is similar to the two-point correlation function of a system in equilibrium with a thermal bath. Calculating the transition rate, the non-uniformly accelerated Unruh-DeWitt detector can be excited even if the scalar field is prepared in the vacuum state.

hep-th↗