The unmasking of thermal Goldstone bosons

The problem of extracting the modes of Goldstone bosons from a thermal background is reconsidered in the framework of relativistic quantum field theory. It is shown that in the case of spontaneous breakdown of an internal bosonic symmetry a recently established decomposition of thermal correlation functions contains certain specific contributions which can be attributed to a particle of zero mass.Comment: 7 pages, LaTeX; new and considerably strengthened results after Eq. (14); to appear in Phys. Rev.

The Reeh-Schlieder property for thermal field theories

We show that the Reeh-Schlieder property w.r.t. the KMS-vector is a direct consequence of locality, additivity and the relativistic KMS-condition. The latter characterises the thermal equilibrium states of a relativistic quantum field theory. The statement remains vaild even if the given equilibrium state breaks spatial translation invariance.Comment: plain tex, 10 page

Invoice from Geo. I. Roberts & Bros.

https://digitalcommons.salve.edu/goelet-new-york/1183/thumbnail.jp

Receipt from Geo. I. Roberts & Bros.

https://digitalcommons.salve.edu/goelet-new-york/1185/thumbnail.jp

Receipt from Geo. I. Roberts & Bros.

https://digitalcommons.salve.edu/goelet-new-york/1219/thumbnail.jp

Conformally invariant wave-equations and massless fields in de Sitter spacetime

Conformally invariant wave equations in de Sitter space, for scalar and vector fields, are introduced in the present paper. Solutions of their wave equations and the related two-point functions, in the ambient space notation, have been calculated. The ``Hilbert'' space structure and the field operator, in terms of coordinate independent de Sitter plane waves, have been defined. The construction of the paper is based on the analyticity in the complexified pseudo-Riemanian manifold, presented first by Bros et al.. Minkowskian limits of these functions are analyzed. The relation between the ambient space notation and the intrinsic coordinates is then studied in the final stage.Comment: 21 pages, LaTeX, some details adde

On the Perturbative Stability of Quantum Field Theories in de Sitter Space

We use a field theoretic generalization of the Wigner-Weisskopf method to study the stability of the Bunch-Davies vacuum state for a massless, conformally coupled interacting test field in de Sitter space. We find that in $\lambda \phi^4$ theory the vacuum does {\em not} decay, while in non-conformally invariant models, the vacuum decays as a consequence of a vacuum wave function renormalization that depends \emph{singularly} on (conformal) time and is proportional to the spatial volume. In a particular regularization scheme the vacuum wave function renormalization is the same as in Minkowski spacetime, but in terms of the \emph{physical volume}, which leads to an interpretation of the decay. A simple example of the impact of vacuum decay upon a non-gaussian correlation is discussed. Single particle excitations also decay into two particle states, leading to particle production that hastens the exiting of modes from the de Sitter horizon resulting in the production of \emph{entangled superhorizon pairs} with a population consistent with unitary evolution. We find a non-perturbative, self-consistent "screening" mechanism that shuts off vacuum decay asymptotically, leading to a stationary vacuum state in a manner not unlike the approach to a fixed point in the space of states.Comment: 36 pages, 4 figures. Version to appear in JHEP, more explanation

Fachada principal del proyecto de la cárcel pública [Material cartográfico] : sección dada por la linea A B de la planta

A la part inferior dreta: el arquitecto de la Real Academia de S. Fernando José Roca y Bros = En la parte inferior derecha: el arquitecto de la Real Academia de S. Fernando José Roca y BrosA la part inferior esquerra: aprobado por la R. Academia de Nobles Artes de S. Fernando en junta gral de 11 de junio de 1834. Il Sr Gl y Com Marsial Antonio Lopez = En la parte inferior izquierda: aprobado por la R. Academia de Nobles Artes de S. Fernando en junta gral de 11 de junio de 1834. Il Sr Gl y Com Marsial Antonio LopezMapa grabat = Mapa grabadoCopia digital. Madrid : Ministerio de Cultura. Subdirección General de Coordinación Bibliotecaria, 200

Planta del primer piso [de la cárcel pública de Figueres] [Material cartográfico]

A la part inferior: el arquitecto de la Real Academia de San Fernando José Roca y BrosA la part inferior dreta: aprobado por la R. Academia de Nobles Artes de S. Fernando en junta general de 11 de junio de 1834. Il Sr Gl y Com Marsial Antonio LopezMapa gravatA la part inferior: numeració dels diferents espaisCopia digital. Madrid : Ministerio de Cultura. Subdirección General de Coordinación Bibliotecaria, 200

Fachada lateral [de la cárcel pública de Figueres] [Material cartográfico] : sección dada por la linea B C D E F G H de la planta

A la part inferior dreta: el arquitecto de la Real Academia de S. Fernando José Roca y Bros = En la parte inferior derecha: el arquitecto de la Real Academia de S. Fernando José Roca y BrosA la part inferior esquerra: aprobado por la R. Academia de Nobles Artes de S. Fernando en junta gral de 11 de junio de 1834. Il Sr Gl y Com Marsial Antonio Lopez = En la parte inferior izquierda: aprobado por la R. Academia de Nobles Artes de S. Fernando en junta gral de 11 de junio de 1834. Il Sr Gl y Com Marsial Antonio LopezMapa gravat = Mapa grabadoCopia digital. Madrid : Ministerio de Cultura. Subdirección General de Coordinación Bibliotecaria, 200