Results 11 to 20 of about 678,025 (58)

The Dyer-Roeder relation in a universe with particle production [PDF]

Astron.Astrophys.422:401-405,2004, 2003
We have obtained analytical exact solutions of the Dyer-Roeder equation in a cosmological model where creation of particles occurs at the expenses of the gravitational field. We discussed the influences of inhomogeneities in the path of a light beam on the apparent diameter of astrophysical objects and consider both redshift independent as redshift ...
arxiv   +1 more source

Política lingüística familiar. O papel dos proxenitores pro-galego na transmisión interxeracional

Estudos de Linguistica Galega, 2019
Nunha sociedade bilingüe cada individuo adulto ten as súas propias prácticas lingüísticas e crenzas sobre a elección do idioma dentro da familia; polo tanto, as prácticas lingüísticas no ámbito familiar son sumamente importantes para entender o
Anik Nandi
semanticscholar   +1 more source

Extended open inflationary universes [PDF]

Phys.Rev. D67 (2003) 063507, 2003
In this paper we study a type of one-field model for open inflationary universe models in the context of the Jordan-Brans-Dicke theory. In the scenario of a one-bubble universe model we determine and characterize the existence of the Coleman-De Lucia instanton, together with the period of inflation after tunnelling has occurred.
arxiv   +1 more source

Functionally Graded Media [PDF]

, 2007
The notions of uniformity and homogeneity of elastic materials are reviewed in terms of Lie groupoids and frame bundles. This framework is also extended to consider the case Functionally Graded Media, which allows us to obtain some homogeneity conditions.
arxiv   +1 more source

Adiabatic decaying vacuum model for the universe [PDF]

Gen.Rel.Grav.35:899-906,2003, 2003
We study a model that the entropy per particle in the universe is constant. The sources for the entropy are the particle creation and a lambda decaying term. We find exact solutions for the Einstein field equations and show the compatibilty of the model with respect to the age and the acceleration of the universe.
arxiv   +1 more source

Noncommutative solitons and instantons [PDF]

, 2003
I review in this talk different approaches to the construction of vortex and instanton solutions in noncommutative field theories.
arxiv   +1 more source

A nonlocal discretization of fields [PDF]

Int.J.Mod.Phys. A16 (2001) 3583-3594, 2000
A nonlocal method to obtain discrete classical fields is presented. This technique relies on well-behaved matrix representations of the derivatives constructed on a non--equispaced lattice. The drawbacks of lattice theory like the fermion doubling or the breaking of chiral symmetry for the massless case, are absent in this method.
arxiv   +1 more source

Estudio Teórico del espectro de emisión para un sistema microcavidad-punto cuántico en una aproximación de campo medio (Theoretical study of emission spectrum for a quantum dot-microcavity system in a mean field approximation) [PDF]

, 2015
En este trabajo, se obtiene una expresi\'on num\'erica para calcular el espectro de emisi\'on de un sistema microcavidad-punto cu\'antico usando una teor\'ia de campo medio en el formalismo de la matriz densidad. El sistema modelado es un micropilar semiconductor que contiene un \'unico punto cu\'antico en el interior de la microcavidad, este sistema ...
arxiv   +1 more source

Ángel Cerrato Álvarez: o compromiso e a galeguidade dun etnógrafo senlleiro

Boletín da Real Academia Galega
Nesta contribución estúdase a traxectoria e a obra dun etnógrafo e historiador, Ángel Cerrato Álvarez, de nacenza vallisoletana e de galeguidade entregada e comprometida.
Alexandre Rodríguez Guerra
semanticscholar   +1 more source

Resultados das terminacións -ANUM, -ANAM, -ANOS e -ANAS en galego

Estudos de Linguistica Galega
O obxectivo desta investigación consiste en describi-los resultados das terminacións -anum, -anam, ‑anos e -anas no concello de Castrelo do Val, na comarca verinesa, no conxunto do galego e no continuum dialectal galego-portugués.
A. S. Alonso Núñez
semanticscholar   +1 more source