WorldCat Identities

Verdaguer, E. (Enric)

Overview
Works: 39 works in 119 publications in 3 languages and 2,410 library holdings
Genres: Conference papers and proceedings 
Roles: Author, Editor, Other, ed
Classifications: QC174.26.W28, 530.14
Publication Timeline
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Most widely held works by E Verdaguer
Gravitational solitons by V Belinski( )

22 editions published between 2001 and 2005 in English and held by 1,858 WorldCat member libraries worldwide

This volume provides an exposition of the theory of gravitational solitons, with a review of exact soliton solutions to Einstein's equations
Relativistic astrophysics and cosmology : proceedings of the XIVth GIFT International Seminar on Theoretical Physics : 27 June-1 July 1983, Sant Feliu de Guíxols, Catalonia, Spain by International Seminar on Theoretical Physics( Book )

16 editions published in 1984 in English and held by 171 WorldCat member libraries worldwide

Semiclassical and stochastic gravity : quantum field effects on curved spacetime by B. L Hu( )

7 editions published in 2020 in English and held by 120 WorldCat member libraries worldwide

"The two pillars of modern physics are general relativity and quantum field theory, the former describes the large scale structure and dynamics of space-time, the latter, the microscopic constituents of matter. Combining the two yields quantum field theory in curved space-time, which is needed to understand quantum field processes in the early universe and black holes, such as the well-known Hawking effect. This book examines the effects of quantum field processes back-reacting on the background space-time which become important near the Planck time (10-43 sec). It explores the self-consistent description of both space-time and matter via the semiclassical Einstein equation of semiclassical gravity theory, exemplified by the inflationary cosmology, and fluctuations of quantum fields which underpin stochastic gravity, necessary for the description of metric fluctuations (space-time foams). Covering over four decades of thematic development, this book is a valuable resource for researchers interested in quantum field theory, gravitation and cosmology"--
Recent developments in gravitation : proceedings of the Relativity Meeting--89, Barcelona, Catalonia, Spain, 5-8 September 1989 by E Verdaguer( Book )

11 editions published between 1990 and 2014 in English and held by 106 WorldCat member libraries worldwide

This volume reviews some recent developments and new perspectives in classical and Quantum Gravity. The topics treated at a graduate level range from some new and old problems in General Relativity, algebraic computing, gravitational wave astronomy to some more speculative subjects as the early Universe, Quantum Gravity and Quantum Cosmology. Contents: Low Energy Effects of Quantum Gravity (E Alvarez); Rigid Motion Invariance of Newtonian and Einstein's Theories of General Relativity (L Bel); General Relativity and the Early Universe (B J Carr); Computer Algebra and Exact Solutions of the Eins
Quantum gravity and cosmology : proceedings of the XXIIth GIFT International Seminar on Theoretical Physics : 3-8 June 1991, Sant Feliu de Guíxols, Catalonia, Spain by GIFT International Seminar on Theoretical Physics( Book )

8 editions published in 1992 in English and Undetermined and held by 73 WorldCat member libraries worldwide

I. QUANTUM GRAVITY: Recent Developments in Nonperturbative Quantum Gravity -- Some General Problems in Quantum Gravity -- The Environment, Decoherence, and the Transition from Quantum to Classical -- II. QUANTUM COSMOLOGY: Introduction and Applications of Quantum Cosmology -- Consequences of Extended Inflation
Semiclassical and stochastic gravity : quantum field effects on curvedspacetim by B. L Hu( )

1 edition published in 2020 in English and held by 13 WorldCat member libraries worldwide

The two pillars of modern physics are general relativity and quantum field theory, the former describes the large scale structure and dynamics of space-time, the latter, the microscopic constituents of matter. Combining the two yields quantum field theory in curved space-time, which is needed to understand quantum field processes in the early universe and black holes, such as the well-known Hawking effect. This book examines the effects of quantum field processes back-reacting on the background space-time which become important near the Planck time (10-43 sec). It explores the self-consistent description of both space-time and matter via the semiclassical Einstein equation of semiclassical gravity theory, exemplified by the inflationary cosmology, and fluctuations of quantum fields which underpin stochastic gravity, necessary for the description of metric fluctuations (space-time foams). Covering over four decades of thematic development, this book is a valuable resource for researchers interested in quantum field theory, gravitation and cosmology
Soliton solutions in spacetimes with two spacelike Killing fields by E Verdaguer( Book )

3 editions published in 1993 in English and held by 12 WorldCat member libraries worldwide

Quantum Gravity and Cosmology - Proceedings of the Xxii Gift International Seminar on Theoretical Physics by E Elizalde( )

2 editions published in 1992 in English and held by 7 WorldCat member libraries worldwide

Stochastic Gravity: Theory and Applications by B. L Hu( )

2 editions published between 2004 and 2008 in English and held by 4 WorldCat member libraries worldwide

Cosmological perturbations including matter loops a study in de Sitter by Markus Benjamin Fröb( )

3 editions published between 2013 and 2014 in English and held by 3 WorldCat member libraries worldwide

In this thesis we studied quantum effects in de Sitter space coming from the interaction of gravitons and matter. We derived the lowenergy effective action for metric perturbations which includes corrections from matter loops, in a flat background for scalar fields of arbitrary mass and minimal curvature coupling, and in a de Sitter background for massless scalar fields of minimal and conformal coupling. From this action we derived the semiclassical Einstein equations, which in this case give a small correction to the relation between the cosmological constant and the Hubble constant. To study the stability of the de Sitter background, we derived the equations satisfied by general linear metric perturbations, using the order reduction method which in contrast to a strictly perturbative treatment produces solutions that are reliable for extended periods of time. We solved these equations for an initial vacuum state and for general initial states. In both cases, the induced changes in the Riemann tensor, which is a gauge invariant and local observable, are small and vanish in the infinite future. In this way, we extended the classical nohair theorems of de Sitter space to the quantum case. We calculated also the two-point function of these perturbations, using a generalization of the flat-space i[epsilon] prescription that permitted us to define an interacting vacuum state [epsilon] in the infinite past. From this correlation function, we obtained a cosmological observable, the power spectrum of tensorial perturbations. The size of the quantum corrections is too small to be measured, being appreciable only if the Hubble constant were of a magnitude comparable to the Planck scale, where the effective theory ceases to be valid. As a local observable, we calculated the two-point function of the Riemann tensor. The result was decomposed into correlation functions of the Weyl and Ricci tensors and the Ricci scalar, which are de Sitter invariant, showing that there is no physical breaking of this invariance. The twopoint function decay exponentially for large separations, showing that the background curvature acts as an effective mass for the graviton. To generalize these calculations to the interaction with other kinds of matter, we exploited the Bianchi identities to show that the two-point function of the Riemann tensor always is de Sitter invariance if this is the case for the stress-energy tensor. We gave explicit formulas to calculate it, and saw that the result is completely determined except for an integration constant. This constant can naturally be interpreted as the strength of free gravitons which propagate in the background spacetime, and depends on the unknown coefficients that multiply terms in the gravitational action which involve squares of curvature tensors
Thermal diagnostics in the LISA Technology Package Experiment by Miquel Nofrarias Serra( )

3 editions published between 2007 and 2008 in English and held by 3 WorldCat member libraries worldwide

Particle propagation in non-trivial backgrounds a quantum field theory approach by D Arteaga( )

3 editions published in 2007 in English and Spanish and held by 3 WorldCat member libraries worldwide

The stochastic semiclassical theory of gravity by Rosario Martín Menéndez( Book )

2 editions published between 1999 and 2000 in English and held by 2 WorldCat member libraries worldwide

Gravitational effects of quantum fields in de Sitter spacetime by Guillem Pérez Nadal( )

2 editions published in 2010 in English and held by 2 WorldCat member libraries worldwide

Cuantización de ondas gravitatorias planas by Manuel Montejo Estévez( Book )

2 editions published between 1999 and 2004 in Spanish and held by 2 WorldCat member libraries worldwide

Calcul du coefficient g∞ de la métrique 2-post-newtonienne pour un système de n-corps fluide parfait et sphériques by E Verdaguer( Book )

2 editions published in 1976 in French and held by 2 WorldCat member libraries worldwide

Métrique 2-post-newtonienne pour un système de n-corps fluide parfait et sphériques : calcul de ℊoi et ℊij by E Verdaguer( Book )

2 editions published between 1975 and 1976 in French and held by 2 WorldCat member libraries worldwide

New applications of the gauge/gravity duality by Daniel Fernández( )

2 editions published in 2013 in English and held by 2 WorldCat member libraries worldwide

Wave propagation in metamaterials mimicking spacetime geometry: black holes and cosmic strings by Isabel Fernández Núñez( Book )

2 editions published in 2018 in English and held by 2 WorldCat member libraries worldwide

In physics, it is common to find different phenomena being described by similar equations. A good analogy can make us look at a problem from a different point of view. In that way, ideas may be transferred from one field of science to another, allowing to model new phenomena after previous, well-studied ones. In the case of the field of analogue gravity, systems that mimic certain aspects of the physics of curved spacetimes are studied. In this thesis, we are interested in the analogy between geometry and media. It has been known for several decades that light propagation in a gravitational field is formally equivalent to that in a bianisotropic medium. On the one hand, ray paths are bent due to spacetime curvature. On the other hand, spatial variations of the permittivity and permeability of a material can make light follow curved trajectories. These two phenomena can be related mathematically in the context of transformation optics, which provides the tools to determine the medium parameters necessary to mimic a certain coordinate transformation. Materials with these specific properties are not naturally occurring, therefore, the emergence of metamaterial science at the beginning of the century was needed to realize them. Metamaterials are artificial composite materials with sub-wavelength constitutive elements that exhibit exotic properties. They have been one of the hot topics of the past years given the variety of opportunities they offer: negative refraction, superlenses, indefinite dispersion, invisibility, among many others. In this thesis we study the analogues of two static spacetimes from the point of view of transformation optics: one with spherical symmetry and one with conical geometry. Both cases are inspired by solutions to Einstein's equations: the Schwarzschild black hole and the cosmic string, respectively. For each case, we derive the permittivity and permeability of the analogous material using Plebanski's formulation of the electromagnetic constitutive equations. We solve numerically the wave equation in the metamaterial and compare the results with analytical theories. We find that the spherically symmetric spacetime can be mimicked by either an anisotropic or isotropic medium due to its rotational symmetries. This is achieved by performing a coordinate transformation of the general metric to a conformally flat form. We obtain the medium parameters for both cases and apply the results to the case of the Schwarzschild black hole. We simulate the propagation of a Gaussian beam in the two materials and compare the numerical results with the null-geodesics in the Schwarzschild spacetime, finding a good agreement. The cosmic string is an example of a topological defect with conical geometry. A conical space can be interpreted as flat space with a wedge removed. We make use of this transformation to study the wave equation in the cosmic string background. We apply asymptotic diffraction theories to obtain analytical models that describe wave propagation of electromagnetic or gravitational waves (in a certain gauge). We find that our expressions reproduce accurately the results of the numerical simulations in the analogous metamaterial. Moreover, with our models, we can understand the observed diffraction pattern as the interference of four characteristic waves. With this interpretation we can introduce the Fresnel observation zones, which are related to the diffraction maxima. They help localize the regions – in either space or frequency – where the wave effects are more significant. In fact, in the diffraction by a non-compact object such as the cosmic string, we find that the contribution to the field of wave effects such as interference or diffraction can be of the same order as the geometrical optics terms. Furthermore, the conical topology also appears in condensed matter systems as disclinations or wedge dislocations, therefore we expect our results to be applicable in those systems as well
 
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Gravitational solitons
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Alternative Names
ENRIC VERDAGUER wetenschapper

Verdaguer, E.

Verdaguer, E. 1950-

Verdaguer, E. (Enric), 1950-

Verdaguer, Enric

Verdaguer, Enric 1950-

Verdaguer, Enrique 1950-

Verdaguer i Oms, Enric 1950-

Verdaguer Oms, Enric

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