Nonrelativistic Dark-energy Fluid in a Baby Universe
نویسندگان
چکیده
We show that the dynamical realization of the acceleration-enlarged Galilean symmetry leads to nonrelativistic massless particles whose energy may be negative. We present a fluid mechanical generalisation of this observation and use it to contruct a nonrelativistic twodimensional fluid model which possesses solutions with a negative energy density. Considering this model as describing dark energy in a baby universe (two space dimensions) we show that its negative energy density leads to a repulsive gravitational interaction of the fluid with any test body.
منابع مشابه
General relativistic, nonstandard model for the dark sector of the Universe
We present a general relativistic version of the self-gravitating fluid model for the dark sector of the Universe (darkon fluid) introduced in Stichel and Zakrzewski (Phys Rev D 80:083513, 2009) and extended and reviewed in Stichel and Zakrzewski (Entropy 15:559, 2013). This model contains no free parameters in its Lagrangian. The resulting energy-momentum tensor is dustlike with a nontrivial e...
متن کامل0 v 2 2 6 A ug 2 00 3 Cosmological constraints on a dark matter – dark energy interaction
It is generally assumed that the two dark components of the energy density of the universe, a smooth component called dark energy and a fluid of nonrelativistic weakly interacting particles called dark matter, are independent of each other and interact only through gravity. In this paper, we consider a class of models in which the dark matter and dark energy interact directly. The dark matter p...
متن کامل0 v 1 1 8 Ju l 2 00 3 Cosmological constraints on a dark matter – dark energy interaction
It is generally assumed that the two dark components of the energy density of the universe, a smooth component called dark energy and a fluid of nonrelativistic weakly interacting particles called dark matter, are independent of each other and interact only through gravity. In this paper, we consider a class of models in which the dark matter and dark energy interact directly. The dark matter p...
متن کاملFormation of Large Structures in the Acceleration Universe with a Hybrid Expansion Law
In the current paper, we have studied the effect of dark energy on for-mation where dark energy exists in the background. For this purpose, we used both WMAP9 and Planck data to study how the radius changes with redshift in these mod-els. We used different data sets to fix the cosmological parameters to obtain a solution for a spherical region under collapse. The mechanism of structure formation f...
متن کاملOn the Degeneracy Inherent in Observational Determination of the Dark Energy Equation of State
Using a specific model for the expansion rate of the Universe as a function of scale factor, it is demonstrated that the equation of state of the dark energy cannot be determined uniquely from observations at redshifts z ∼ a few unless the fraction of the mass density of the Universe in nonrelativistic particles, ΩM , somehow can be found independently. A phenomenological model is employed to d...
متن کامل