The entangling side of the Unruh-Hawking effect

We show that the Unruh effect can create net quantum entanglement between inertial and accelerated observers depending on the choice of the inertial state. This striking result banishes the extended belief that the Unruh effect can only destroy entanglement and furthermore provides a new and unexpected source for finding experimental evidence of the Unruh and Hawking effects.Comment: 4 pages, 4 figures. Added Journal referenc

Localised projective measurement of a relativistic quantum field in non-inertial frames

We propose a scheme to study the effect of motion on measurements of a quantum field carried out by a finite-size detector. We introduce a model of projective detection of a localised field mode in an arbitrary reference frame. We apply it to extract vacuum entanglement by a pair of counter-accelerating detectors and to estimate the Unruh temperature of a single accelerated detector. The introduced method allows us to directly relate the observed effects with the instantaneous proper acceleration of the detector.Comment: 5 pages, 2 figures. v2 Significant increase in the detail level regarding the motivation of the detector mode

The time traveler's guide to the quantization of zero modes

We study the relationship between the quantization of a massless scalar field on the two-dimensional Einstein cylinder and in a spacetime with a time machine. We find that the latter picks out a unique prescription for the state of the zero mode in the Einstein cylinder. We show how this choice arises from the computation of the vacuum Wightman function and the vacuum renormalized stress-energy tensor in the time-machine geometry. Finally, we relate the previously proposed regularization of the zero mode state as a squeezed state with the time-machine warp parameter, thus demonstrating that the quantization in the latter regularizes the quantization in an Einstein cylinder

One- and two- dimensional models are equally effective inmonitoring the crust’s thermal response to advection bylarge-scale thrusting during orogenesis

Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu

A general framework for nonholonomic mechanics: Nonholonomic Systems on Lie affgebroids

This paper presents a geometric description of Lagrangian and Hamiltonian systems on Lie affgebroids subject to affine nonholonomic constraints. We define the notion of nonholonomically constrained system, and characterize regularity conditions that guarantee that the dynamics of the system can be obtained as a suitable projection of the unconstrained dynamics. It is shown that one can define an almost aff-Poisson bracket on the constraint AV-bundle, which plays a prominent role in the description of nonholonomic dynamics. Moreover, these developments give a general description of nonholonomic systems and the unified treatment permits to study nonholonomic systems after or before reduction in the same framework. Also, it is not necessary to distinguish between linear or affine constraints and the methods are valid for explicitly time-dependent systems.Comment: 50 page

Integral field spectroscopy of type-II QSOs at z=0.3-0.4

We present and analyse integral-field observations of six type-II QSOs with z=0.3-0.4, selected from the Sloan Digital Sky Survey (SDSS). Two of our sample are found to be surrounded by a nebula of warm ionized gas, with the largest nebula extending across 8" (40 kpc). Some regions of the extended nebulae show kinematics that are consistent with gravitational motion, while other regions show relatively perturbed kinematics: velocity shifts and line widths too large to be readily explained by gravitational motion. We propose that a ~20 kpc x20 kpc outflow is present in one of the galaxies. Possible mechanisms for triggering the outflow are discussed. In this object, we also find evidence for ionization both by shocks and the radiation field of the AGN.Comment: 6 pages, 5 figures, accepted by MNRAS Letter

Estrategia imperial y crédito local. El archipiélago de Malvinas en la construcción de la frontera hispánica (1767-1774)

This article investigates the role of the Malvinas/Falkland Islands in the reconfiguration of Hispanic American space since 1767. It articulates three variables of analysis: the geopolitical importance of the Malvinas/Falkland Islands on a global scale, their place in the redefinition of the Spanish monarchy’s imperial frontier, and the role played by the economic actors of the Río de la Plata in the colonization of the archipelago. Using political, cartographical and fiscal sources, this work demonstrates that the consolidation of borders —a necessity for the Monarchy— depended on a confluence of interests with local financial oligarchies.El presente artículo indaga el rol del archipiélago de Malvinas en la reconfiguración del espacio hispanoamericano desde 1767. Para ello, se articulan tres variables de análisis: la importancia geopolítica de las islas Malvinas a escala global, su lugar en la redefinición de la frontera imperial de la monarquía española, y el papel que los actores económicos del Río de la Plata tuvieron en la colonización del archipiélago. Empleando documentación política, cartográfica y fiscal, este trabajo demuestra que la consolidación de las fronteras que la Monarquía precisaba asegurar confluyó con los intereses de las oligarquías financieras locales