Albus 1: A very bright white dwarf candidate

We have serendipitously discovered a previously-unknown, bright source (B_T = 11.75+/-0.07 mag) with a very blue V_T-K_s color, to which we have named Albus 1. A photometric and astrometric study using Virtual Observatory tools has shown that it possesses an appreciable proper motion and magnitudes and colors very similar to those of the well known white dwarf G 191-B2B. We consider Albus 1 as a DA-type white dwarf located at about 40 pc. If confirmed its nature, Albus 1 would be the sixth brightest isolated white dwarf in the sky, which would make it an excellent spectrophotometric standard.Comment: ApJ Letters, in pres

Entanglement through qubit motion and the dynamical Casimir effect

We explore the interplay between acceleration radiation and the dynamical Casimir effect (DCE) in the field of superconducting quantum technologies, analyzing the generation of entanglement between two qubits by means of the DCE in several states of qubit motion. We show that the correlated absorption and emission of photons is crucial for entanglement, which in some cases can be linked to the notion of simultaneity in special relativity

Milicia, fueros y acción del poder real sobre Aragón entre 1562-1642

Entre els anys 1562 i 1642 les relacions mantingudes entre la Corona i el regne d’Aragó, així com la dialèctica política i jurisdiccional que en va derivar, es van veure condicionades per la pretensió per part de la Monarquia de configurar un aparell de guerra capaç de respondre a les exigències derivades dels objectius polítics que perseguia en l’àmbit internacional. En arribar a les Corts de Saragossa de 1645-1646 les condicions del «servei d’armes aragonès» no havien canviat gaire, si més no en allò relatiu als seus aspectes estructurals i de mobilització. Però l’accès a aquest servei perseguit per la Corona en l’exercici del seu poder, per mitjà d’un procés de transformació social i d’adaptació dels furs del regne a tal fi, era una realitat.Between the years 1562 and 1642 the relations maintained between the Spanish crown and the kingdom of Aragon, as well as the political and jurisdictional dialectics that they created, were conditioned by the desire on behalf of the Spanish monarchy to consolidate a war appartus capable of responding to the demands derived from the political objectives that it was pursuing in the international sphere. By the time of the Cortes of Saragossa which began in 1645, the conditions of the Aragonese military subsidies had hardly changed from earlier periods, at least with regard to its structural aspects and ways of mobilization. But the crown’s ability to intervene into it, through a process of social transformation and of adaptation of the fueros (laws and privileges) of the kingdom to such effect was a reality

Approximate Quantum Adders with Genetic Algorithms: An IBM Quantum Experience

It has been proven that quantum adders are forbidden by the laws of quantum mechanics. We analyze theoretical proposals for the implementation of approximate quantum adders and optimize them by means of genetic algorithms, improving previous protocols in terms of efficiency and fidelity. Furthermore, we experimentally realize a suitable approximate quantum adder with the cloud quantum computing facilities provided by IBM Quantum Experience. The development of approximate quantum adders enhances the toolbox of quantum information protocols, paving the way for novel applications in quantum technologies