Gravitational Redshift Induces Quantum Interference

Quantum field theory in curved spacetime is used to show that gravitational redshift induces a unitary transformation on the quantum state of propagating photons. It is found that the transformation is a mode-mixing operation, and a protocol that exploits gravity to induce a Hong–Ou–Mandel-like interference effect on the state of two photons is devised. It is discussed how the results of this work can provide a demonstration of quantum field theory in curved spacetime.     

Precession of Orbiting Gyroscope in Higher-Order Gravitational Field Caused by Rotating Body

The metric for a spinning massive object with any shape and composition is found by the use of linearized higher-order theory of gravitation. The geodesic and the Lense–Thirring precessions for an orbiting gyroscope in a general weak higher-order gravitational field are considered. The influences of the additional Yukawa forces included in the linearized higher-order gravitation on the precessions are investigated.     

The Surface Gravitational Redshift of a Proto Neutron Star

The influence of the δ and Ф mesons on the surface gravitational redshift of a proto neutron star is investigated within the framework of relativistic mean field theory for the baryon octet： {n, p, A, ∑-, ∑0 ,∑＋, , 0} system. It is found that, compared with those without considering the contribution of σ and Ф mesons, the surface gravitational redshift decreases, corresponding to the maximum value of the mass decreasing from 0.2220 to 0.1937, about 12.7%. It is also found that the appearance of σ and Ф mesons makes the surface gravitational redshift as a function of M/R decrease too, with M and R being the mass and radius of the proto neutron star.     

Quantum Hydrodynamics,Rotating Superfluid and Gravitational Anomaly

Journal of Experimental and Theoretical Physics - We present a consistent scheme of quantization of chiral flows (flows with extensive vorticity) in ideal hydrodynamics in two dimensions. Chiral...     

Gravitational Instability of a Rotating Viscous Finitely Conducting Plasma

The gravitational instability of infinite homogeneous plasma has been studied to include simultaneously the effects of rotations, Hall currents, viscosity, finite electrical conductivity and the finite Larmor radius (FLR). Both the longitudinal, and transverse modes of wave propagation have been studied. It is found that the gravitational instability is determined by Jeans' criterion even in the presence of effects of rotation, Hall currents, FLR, viscosity and finite conductivity whether included separately or jointly.     

Gravitational Instability of a Rotating Viscous Thermally Conducting Plasma

This paper deals with the gravitational instability of an infinite homogeneous viscous rotating plasma of finite electrical conductivity in the combined presence of effects of Hall currents, finite Larmor radius (FLR) and thermal conductivity. The ambient magnetic field is assumed to be uniform and acting along the vertical direction. Both longitudinal and transverse modes of wave propagation have been studied. It is shown that Jean's criterion determines the gravitational instability even in the presence of the effects of thermal conductivity, viscosity, finite electrical conductivity, FLR, rotation and Hall currents. Further it is found that while FLR, viscosity and rotation have a stabilizing influence, both the thermal and the electrical conductivities have a destabilizing influence on the gravitational instability of a plasma.     

Constraining the Surface Gravitational Redshift of Proto Neutron Stars with New Nucleon Coupling Constants

A new set of nucleon coupling constants (CZ11) is obtained for the relativistic mean field (RMF) theory based on the recent experimental information on the symmetry energy derived from the data from NSCL/MSU. The surface gravitational redshift of a proto neutron star (PNS) is examined within the RMF framework for the baryon octet system by using this set of parameters. It is found that the surface gravitational redshift for CZ11 is smaller than that for GL97. For the CZ11 parameter set, the surface gravitational redshift of a PNS at T=15 MeV is smaller than that at T=0 MeV. It is also found that the surface gravitational redshift corresponding to M _max/R for the CZ11 parameter set is smaller by about 10 percent than that for GL97, with M _max being the maximum mass and R being the corresponding radius.     

Suspended Particles and the Gravitational Instability of Rotating Magnetised Medium

The effect of uniform rotation on the self gravitational instability of an infinite homogeneous magnetised gas particle medium in the presence of suspended particles is investigated. The equations of the problem are linearized and the general dispersion relation for such system is obtained. The rotation is assumed along two different directions and separate dispersion relation for each case is obtained. The dispersion relation for propagation parallel and perpendicular to the uniform magnetic field along with rotation is derived. The effect of suspended particles on the different modes of propagation is investigated. It is found that in presence of suspended particles, magnetic field, rotation and viscosity, Jeans' criterion determines the condition of gravitational instability of gas-particle medium.     

Cosmological Redshift. An Information Mechanics Perspective

A photon's observed wavelength tells anastronomical detector about the amount of positioninformation obtained by observing that photon. Thisamount of position information may depend on time in away which, to first order over distances smallcompared to the size of the universe, might account forthe cosmological redshift.     

An Approximated Solution of the Einstein Equations for a Rotating Body with Negligible Mass

The paper considers the problem of finding the metric of space time around a rotating, weakly gravitating body. Both external and internal metric tensors are consistently found, together with an appropriate source tensor. All tensors are calculated at the lowest meaningful approximation in a power series. The two physical parameters entering the equations (the mass and the angular momentum per unit mass) are assumed to be such that the mass effects are negligible with respect to the rotation effects. A non zero Riemann tensor is obtained. The order of magnitude of the physical effects is discussed.     

The Gravitational Instability of a Finitely Conducting Rotating Plasma Through a Porous Medium

The magneto-gravitational instability of an infinite homogeneous, finitely conducting, viscous rotating plasma through porous medium is investigated in view of its relevance to certain stellar atmospheres. The dispersion relation has been obtained from the relevant linearized perturbation equations of the problem and it has been discussed in the case of rotation parallel and perpendicular to the direction of magnetic field separately. The longitudinal and transverse modes of wave propagation are discussed in each case of rotation. It is found that the combined effect of viscosity, finite conductivity, rotation and the medium porosity does not essentially change the Jeans' criterion of gravitational instability. It is also shown that for the propagation transverse to the direction of magnetic field. the finite conductivity destabilizes the wave number band which is stable in the limit of infinite conductivity when the medium is considered inviscid.     

Effects of the Interaction of a Rotating Ideal Liquid with a Vortical Gravitational Field

Russian Physics Journal - Stationary configurations of self-gravitating, rotating liquids with barotropic equation of state are considered within the framework of GTR. It is shown that such a...     

Gravitational field from photons

The gravitational field created by a single photon is determined by taking into account the relativistic mass of the photon as source of gravitational interaction. In addition, the total force (due to the above field) over an accelerated particle is calculated in the light of the general theory of relativity. Some aspects related to the photon as an ultrarelativistic particle are discussed.     

Rotating Electrically Charged Ideal Liquid with Magnetic and Vortex Gravitational Fields in General Relativity

Russian Physics Journal - Stationary configuration of a rotating electrically charged ideal fluid with self-gravitation is considered within the framework of general relativity. Barotropic equation...     

Gravitational waves from an axi-symmetric source in the Nonsymmetric Gravitational Theory

We examine gravitational waves in an isolated axi-symmetric reflexion symmetric system in the framework of the Nonsymmetric Gravitational Theory (ngt). The vacuum field equations are analyzed and the exact solution for the field variables in the metric tensor are found in the form of expansions in powers of a radial coordinate. We find that when the system radiates, the mass decreases monotonically and the energy flux associated with waves is positive.