相关论文: Discrete Space Time and Dark Energy

We abandon the interpretation that time is a global parameter in quantum mechanics, replace it by a quantum dynamical variable playing the role of time. This operational re-interpretation of time provides a solution to the cosmological…

The gap between a microscopic theory for quantum spacetime and the semiclassical physics of blackholes is bridged by treating the blackhole spacetimes as highly excited states of a class of nonlocal field theories. All the blackhole…

It has recently been proposed that quantum gravity might lead to the decoherence of superpositions in energy, corresponding to a discretization of time at the Planck scale. At first sight the proposal seems amenable to experimental…

We discuss a novel explanation of the dark energy as a manifestation of macroscopic non-locality coming from quantum gravity, as proposed by Markopoulou. It has been previously suggested that in a transition from an early quantum geometric…

The observed dark energy in the universe might give particles inertial mass. We investigate one realization of this idea, that the dark energy field might be a decayed scalar component of a supermultiplet field in the early universe that…

In order to understand the nature of the accelerating expansion of the late-time universe, it is important to experimentally determine whether dark energy is a cosmological constant or dynamical in nature. If dark energy already exists…

Time crystals are a phase of matter, for which the discrete time symmetry of the driving Hamiltonian is spontaneously broken. The breaking of discrete time symmetry has been observed in several experiments in driven spin systems. Here, we…

The exact solution for dynamic of conform-flat space homogeneous since dynamic equation is given. Conform mode of space metric changing in Global time theory has negative energy density. Swap of energy to this mode from another ones lead to…

Within the framework of the modified geodetic brane gravity, conformed by the Regge-Teitelboim model and enhanced with a linear term in the extrinsic curvature of the brane, the possibility that under an FRW geometry this theory emulates…

Late-time cosmic acceleration is one of the most interesting unsolved puzzles in modern cosmology. The explanation most accepted nowadays, dark energy, raises questions about its own nature, e.g. what exactly is dark energy, and…

Models where Dark Matter and Dark Energy interact with each other have been proposed to solve the coincidence problem. We review the motivations underlying the need to introduce such interaction, its influence on the background dynamics and…

The discovery that we live in an accelerating universe changed drastically the paradigm of physics and introduced the concept of \textit{dark energy}. In this work, we present a brief historical description of the main events related to the…

In the event symmetric approach to quantum gravity it is assumed that the fundamental laws of physics must be invariant under exchange of any two space-time events. The fact that this symmetry if obviously not observed is attributed to the…

High precision cosmological observations in last decade suggest that about 70% of our universe's energy density is in so called "Dark Energy" (DE). Observations show that DE has negative effective pressure and therefore unlike conventional…

We consider late-time cosmology in a (phantom) scalar-tensor theory with an exponential potential, as a dark energy model with equation of state parameter close to -1 (a bit above or below this value). Scalar (and also other kinds of)…

Effective quantum cosmology is formulated with a realistic global internal time given by the electric vector potential. New possibilities for the quantum behavior of space-time are found, and the high-density regime is shown to be very…

Within the limits of the present cosmological observations in f(R,T) gravity theory, we have analyzed a spherically symmetric space-time in 5D setting. The field equations have been carefully studied considering reasonable cosmological…

We present here a brief review and discussion on recent developments in the theory of spacetime singularities. After mentioning some key motivations on the main ideas and concepts involved, we take the approach that the singularities will…

Phenomena currently attributed to Dark Matter (DM) and Dark Energy (DE) are merely a result of the interplay between gravitational energy density, caused by the contraction of space by matter, and space dilation, caused by the energy…

Dark energy (DE) is not necessarily uniform when other sources of gravity are present: interaction with matter leads to its variation in space and time. We study cosmological implications of this fact by analyzing cosmological models in…