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We show that vector theories on cosmological scales are excellent candidates for dark energy. We consider two different examples, both are theories with no dimensional parameters nor potential terms, with natural initial conditions in the early [...]texto impreso
Beltrán Jiménez, José ; Cruz Dombriz, Álvaro de la ; Dunsby, Peter K. S. ; Sáez Gómez, Diego | IOP publishing ltd | 2014-05-21One possible explanation for the present observed acceleration of the Universe is the breakdown of homogeneity and isotropy due to the formation of non-linear structures. How inhomogeneities affect the averaged cosmological expansion rate and le[...]texto impreso
We discuss an extended version of electromagnetism in which the usual gauge fixing term is promoted into a physical contribution that introduces a new scalar state in the theory. This new state can be generated from vacuum quantum fluctuations d[...]texto impreso
In this work we show that the presence of a vector field on cosmological scales could explain the present phase of accelerated expansion of the Universe. The proposed theory contains no dimensional parameters nor potential terms and does not req[...]texto impreso
It has been recently shown that the presence of a vector field over cosmological scales could explain the observed accelerated expansion of the Universe without introducing either new scales or unnatural initial conditions in the early Universe,[...]texto impreso
We show that the presence of a temporal electromagnetic field on cosmological scales generates an effective cosmological constant which can account for the accelerated expansion of the universe. Primordial electromagnetic quantum fluctuations pr[...]texto impreso
We present a detailed study of the cosmological evolution in general vector-tensor theories of gravity without potential terms. We consider the evolution of the vector field throughout the expansion history of the Universe and carry out a classi[...]texto impreso
In this work we consider an extended electromagnetic theory in which the scalar state which is usually eliminated by means of the Lorenz condition is allowed to propagate. This state has been shown to generate a small cosmological constant in th[...]texto impreso
We study the consequences of a homogeneous dark energy fluid having a nonvanishing velocity with respect to the matter and radiation large-scale rest frames. We consider homogeneous anisotropic cosmological models with four fluids (baryons, radi[...]texto impreso
We consider an extended electromagnetic theory in which the scalar state which is usually eliminated be means of the Lorenz condition is allowed to propagate. On super-Hubble scales, such a state is given by the temporal component of the electro[...]texto impreso
We consider a general class of vector-tensor theories of gravity and show that solutions with accelerated expansion and a future type III singularity are a common feature in these models. We also show that there are only six vector tensor theori[...]texto impreso
In this work we consider the most general electromagnetic theory in curved space-time leading to linear second order differential equations, including non-minimal couplings to the space time curvature. We assume the presence of a temporal electr[...]texto impreso
Is there an absolute cosmic electric potential? The recent discovery of the accelerated expansion of the universe could be indicating that this is certainly the case. In this essay we show that the consistency of the covariant and gauge-invarian[...]texto impreso
Large-scale matter bulk flows with respect to the cosmic microwave background have very recently been detected on scales less than or similar to 100h(-1) Mpc and less than or similar to 300h(-1) Mpc by using two different techniques showing an e[...]texto impreso
López Maroto, Antonio ; Beltrán Jiménez, José ; Gottloeber, Stefan ; Yepes Alonso, Gustavo ; Knebe, Alexander ; Carlesi, Edoardo | Wiley-Blackwell | 2012-07We present the results of a series of cosmological N-body simulations of a vector dark energy (VDE) model, performed using a suitably modified version of the publicly available gadget-2 code. The set-ups of our simulations were calibrated pursui[...]
