Related papers: Extra dimensions, preferred frames and ether-drift…
We investigate some interesting solutions in the DSR theories. These solutions have important features in optics and mechanics. We use these similarities for a better understanding of these theories. We know that, the vacuum in the DSR has…
High-energy end of the cosmic-ray spectrum has provided us to check a validity of the Lorentz Invariance and the Relativity principle, through the observation of the so-called GZK cut-off. It is claimed in this report that the comoving…
We discuss the quantum-bouncer experiment involving ultracold neutrons in a braneworld scenario. Extra-dimensional theories typically predict the strengthening of gravitational interactions over short distances. In this paper, we…
We propose, in a heuristic way, a relativistic modified gravity model as an alternative to particle dark matter at galactic scales. The model is based on a postulated preferred time foliation described by a dynamical scalar field called the…
Graviton production due to collapsing extra dimensions is studied. The momenta lying in the extra dimensions are taken into account. A $D$-dimensional background is matched to an effectively four-dimensional standard radiation dominated…
The topology of extra dimensions can break global Lorentz invariance,singling out a globally preferred frame even in flat spacetime. Through experiments that probe global topology, an observer can determine her state of motion with respect…
Does relativistic gravity provide arguments against the existence of a preferred frame? Our answer is negative. We define a viable theory of gravity with preferred frame. In this theory, the EEP holds exactly, and the Einstein equations of…
According to several authors, gravity might be a long-wavelength phenomenon emerging in some 'hydrodynamic limit' from the same physical, flat-space vacuum viewed as a form of superfluid medium. In this framework, light might propagate in…
Basic foundational aspects of both quantum theory and relativity might induce to represent the physical vacuum as an underlying highly turbulent fluid. By explicit numerical simulations, we show that a form of statistically isotropic and…
We study the physics of a single discrete gravitational extra dimension using the effective field theory for massive gravitons. We first consider a minimal discretization with 4D gravitons on the sites and nearest neighbor hopping terms. At…
We consider the twin paradox of special relativity in a universe with a compact spatial dimension. Such topology allows two twin observers to remain inertial yet meet periodically. The paradox is resolved by considering the relationship of…
After an overview of various citations relevant in the context of photon propagation, the relativistic Doppler effect and the addition theorem of velocities are first derived taking into account momentum and energy conservation. Clocks and…
The condensation of elementary quanta and their macroscopic occupation of the same quantum state, say k=0 in some reference frame Sigma, is the essential ingredient of the degenerate vacuum of present-day elementary particle physics. This…
A new approach in the Newtonian space and time, based upon the assumption that inertial mass is the quantitative measure of the matter. It has been shown that in case of a special physical system, a supposed matter transfer may reproduce…
Models that involve extra dimensions have introduced completely new ways of looking up on old problems in theoretical physics. The aim of the present notes is to provide a brief introduction to the many uses that extra dimensions have found…
We summarize a recent work on the title subject, skipping the detailed calculations but introducing the basic points with enough detail. The theory considered is formulated in a preferred reference frame in a four-dimensional spacetime…
We discuss possible observational manifestations of static, spherically symmetric solutions of a class of multidimensional theories of gravity, which includes the low energy limits of supergravities and superstring theories as special…
Recently proposed theories based on the cosmic presence of a vectorial field are compared and contrasted. In particular the so called Einstein aether theory is discussed in parallel with a recent proposal of a strained space-time theory…
The possibility that spacetime is extended beyond the familiar 3+1-dimensions has intrigued physicists for a century. Indeed, the consequences of a dimensionally richer spacetime would be profound. Recently, new theories with higher…
We consider cosmology in the Einstein-aether theory (the generally covariant theory of gravitation coupled to a dynamical timelike Lorentz-violating vector field) with a linear aether-Lagrangian. The 3+1 spacetime splitting approach is used…