Related papers: Tachyonic dark matter
Following earlier studies that provided a consistent theory of kinematics for tachyons (faster-than-light particles) we here embark on a study of tachyon dynamics, both in classical physics and in the quantum theory. Examining a general…
In this paper a possibility of the accelerated expansion of the large scale universe with a varying polytropic fluid of a certain type is presented. About a special role of non-gravitational interactions between dark energy and dark matter,…
Recent results indicate the presence of a cosmological constant (or related dark energy) in the universe. It has been conjectured recently that the interaction parameters of physical theories may be dependant on the size parameter of the…
We use anisotropic fluid cosmology to describe the present, dark energy-dominated, universe. Similarly to what has been proposed for galactic dynamics, the anisotropic fluid gives an effective description of baryonic matter, dark energy and…
Recent measurements suggest our universe has a substantial dark energy component, which is usually interpreted in terms of a cosmological constant. Here we examine how much the form of this dark energy can be modified while still retaining…
Astrophysics gives evidence for the existence of Dark Matter and puts constraints on its nature. The Cold Dark Matter model has become "standard" cosmology combined with a cosmological constant. There are indications that "Cold" Dark Matter…
In the present report we make an attempt to give an answer to the question of modern cosmology about the nature of the dark matter and energy in our universe. On the basis of our quantum cosmological approach, proposed in 1997-2002, we show…
We study the effects of superfluid dark matter on the structure of a cosmic string wake, considering both the effects of regular and quantum pressure terms. We consider the total fluid to consist of a combination of baryons and dark matter.…
Dark matter is a fundamental constituent of the universe, which is needed to explain a wide variety of astrophysical and cosmological observations. Although the existence of dark matter was first postulated nearly a century ago and its…
The increasing quality of cosmological data has revealed some tensions that could be signalling the necessity of incorporating new physics into our cosmological model. One particularly intriguing possibility is the existence of elastic…
Here, creation of the universe is obtained only from gravity sector. The dynamical universe begins with two basic ingredients (i) vacuum energy, also called dark energy (as vacuum energy is not observed) and (ii) background radiation. These…
We show that Dark Matter consisting of bosons of mass of about 1eV or less has critical temperature exceeding the temperature of the universe at all times, and hence would have formed a Bose-Einstein condensate at very early epochs. We also…
We examine whether tachyon matter is a viable candidate for the cosmological dark matter. First, we demonstrate that in order for the density of tachyon matter to have an acceptable value today, the magnitude of the tachyon potential energy…
We push ahead the idea developed in [24], that some fraction of the dark matter and the dark energy can be explained as a relativistic effect. The inhomogeneity matter generates gravitational distortions, which are general relativistically…
A set of temporal singularities (transients) in the mass-energy density and pressure, bearing a specific mathematical structure which represents a new solution to the continuity equation (\ie~conservation of mass-energy) and satisfying the…
Introduction to the meaning of dark matter and a few historical gestures. What it is? By what the dark matter is formed? Experimental phenomenon evidences and relative explanation under the point of view of the physics of the elementary…
We discuss the coupling between dark energy and matter by considering a homogeneous tachyonic scalar field as a candidate for dark energy. We obtained the functional form of scale factor by assuming that the coupling strength depends…
The history of dark universe physics can be traced from processes in the very early universe to the modern dominance of dark matter and energy. Here, we review the possible nontrivial role of strong interactions in cosmological effects of…
Last year observations had a profound impact on our views on the amount and nature of dark matter in the universe. We give a brief review of the recent history of dark matter models beyond the pure cold dark matter universe. In view of the…
We investigate the possibility that the observed behavior of test particles outside galaxies, which is usually explained by assuming the presence of dark matter, is the result of the dynamical evolution of particles in higher dimensional…