相关论文: Dynamics of Tachyonic Dark Matter

A Friedmann-Robertson-Walker cosmological model dominated by tachyonic -- faster-than-light -- dark matter can exhibit features similar to those of a standard dark energy/dark matter or $Lambda$CDM model. It can undergo expansion which…

A cosmology is considered driven by a stress-energy tensor consisting of a perfect fluid, an inhomogeneous pressure term (which we call a ``tachyonic dust'' for reasons which will become apparent) and a cosmological constant. The…

Recent attempts to explain the dark matter and energy content of the universe have involved some radical extensions of standard physics, including quintessence, phantom energy, additional space dimensions and variations in the speed of…

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…

This work expands previous efforts, within the classical theories of Special and General Relativity, to include tachyons (faster-than-light particles) along with ordinary (slower-than-light) particles at any energy. The objective here is to…

Here, non-minimally coupled tachyon to gravity is considered as a source of "dark energy". It is demonstrated that with expansion of the universe, tachyon dark energy decays to "dark matter" providing a solution to "cosmic coincidence…

This paper presents an investigation of cosmological dynamics of tachyon fluid coupled to varyingmass dark matter particles in the background of spatially flat FLRW universe. The mechanism of varying mass particles scenario assumes the mass…

It is suggested that charged tachyons of extremely large mass M could not only contribute to the dark matter needed to fit astrophysical observations, but could also provide an explanation for gamma ray bursts and ultra high energy cosmic…

We consider the motion of tachyons (faster-than-light particles) in the framework of General Relativity. An important feature is the large contribution of low energy tachyons to the energy-momentum tensor. We also calculate the…

In this work we investigate the background dynamics when dark energy is coupled to dark matter with a suitable interaction in the universe described by Einstein-Aether gravity. Dark energy in the form of Modified Chaplygin gas is…

Axions and axion-like particles are ubiquitous in extensions of the Standard Model and offer a unifying framework for addressing open problems in cosmology. Depending on their mass and interactions, axions can act as dark matter, drive…

We consider the prospects for dark matter/energy unification in k-essence type theories. General mappings are established between the k-essence scalar field, the hydrodynamic and braneworld descriptions. We develop an extension of the…

This paper reports improvements and new results for a well developed theory of tachyons (faster-than-light particles) and follows the suggestion that neutrinos - especially the low energy neutrinos in the Cosmic Neutrino Background - may be…

A new cosmological theory is proposed in the theoretical framework of modified gravity theories which is based on a tachyonic field non-minimally coupled with a specific topological invariant constructed with third order contractions of the…

An open or hyperbolic Friedmann-Robertson-Walker spacetime dominated by tachyonic dark matter can exhibit an ``inflected'' expansion -- initially decelerating, later accelerating -- similar but not identical to that of now-standard…

The present work is an example of the application of the dynamical system analysis in the context of cosmology. Here cosmic evolution is considered in the background of homogeneous and isotropic flat Friedmann-Lema\^{i}tre-Robertson-Walker…

Quintessence theories for cosmic acceleration imbue dark energy with a non-trivial dynamics that offers hope in distinguishing the physical origin of the component. We review quintessence models with an emphasis on this dynamics and discuss…

Dark matter substructure has the potential to discriminate between broad classes of dark matter models. With this in mind, we construct novel solutions to the equations of motion governing condensate dark matter candidates, namely axion…

Velocity-dependent interactions in a fundamental-string dominated universe lead quite naturally, with reasonable assumptions on initial conditions, to an accelerating expanding universe without assuming the existence of a cosmological…

It is demonstrated that dark energy, driven by tachyons having non-minimal coupling with curvature and self-interacting inverse cubic potential, decays to cold dark matter in the late universe. It is found that this penomenon yields a…