Abstract:
Attention is drawn to the fact that the well-known expression for the red-shift of spectral lines due to a gravitational field may be derived with no recourse to the theory of general relativity. This raises grave doubts over the inclusion of the measurement of this gravitational red-shift in the list of crucial tests of the theory of general relativity.

Abstract:
Einstein relativity theory shows its high capability of promoting itself to solve the long stand physical problems. The so-called generalized special relativity (GSR) was derived later, using the beautiful Einstein relation between field and space-time curvature. In this work we re-derive (GSR) expression of time by incorporating the field effect in it, and by using mirror clock and Lorentz transformations. This expression reduces to that of (GSR) the previous conventional one, besides reducing to special relativistic expression. It also shows that the speed of light is constant inside the field and is equal to C. This means that the observed decrease of light in matter and field is attributed to the strong interaction of photons with particles and mediates which causes successive absorption and reemission processes that lead to time delay. This absorption process makes some particles appear to move faster than light within the field or medium. This new expression, unlike that of GSR, can describe time and coordinate relativistic expressions for strong as well as weak fields at constant acceleration.

Abstract:
The k-calculus was advocated by Hermann Bondi as a means of explaining special relativity using only GCSE level mathematics and ideas. We review the central derivations, using proofs which are only a little more elegant than those in Bondi's books, and extend his development to include the scalar product and the mass shell condition. As used by Bondi, k is the Doppler red shift, and we extend the k calculus to include the gravitational red shift and give a derivation of Newton's law of gravity using only 'A' level calculus and basic quantum mechanics.

Abstract:
The standard theory of relativity is based on the hypothesis of locality. The locality principle assumes that an object is affected only by its immediate surroundings and not by variables in the past. It follows that in standard relativity theory even wave properties are measured instantaneously. This contradicts the Bohr-Rosenfeld principle, according to which fields cannot be determined instantaneously. Nonlocal special relativity resolves the problem by taking past history into account. The current status of nonlocal electrodynamics is discussed and a new consequence of nonlocality, namely, a certain additional amplitude shift due to nonlocality in the spin-rotation coupling is presented.

Abstract:
The k-calculus was advanced by Hermann Bondi as a means of explaining special relativity using only simple algebra (Bondi H.: Relativity and Common Sense, London, Heinemann, 1964). As used by Bondi, k is Doppler shift. This paper extends the k-calculus to include gravitational red shift and to develop techniques for an introductory treatment of general relativity in which the emphasis is on mathematical deduction from physical measurement procedure. Using ideas of geometric optics, geodesic motion is understood from the refraction of the wave function due curvature. The k-calculus gives a very simple derivation of Schwarzschild, showing that the geometry is equivalent to the existence of a fundamental minimum time, proportional to rest mass, between the interactions of elementary particles. The Newtonian approximation is seen from direct application of red shift to the wave function. Finally differential geometry is introduced, showing that the k-calculus gives an equivalent treatment of general relativity up to and including the general form of Einstein's field equation.

Abstract:
The kinematical successes of general relativity are legendary: the perihelion precession, the gravitational red-shift, the bending of light. However, at the level of dynamics, relativity is faced with insurmountable difficulties. It has failed to define the energy, momentum, and stress of the gravitational field. Moreover, it offers no expression of energy-momentum transfer to or from the gravitational field. These are symptoms of a far graver malady: general relativity violates the principle of energy conservation.

Abstract:
A new satellite based test of Special and General Relativity is proposed. For the Michelson-Morley experiment we expect an improvement of at least three orders of magnitude, and for the Kennedy-Thorndike experiment an improvement of more than one order of magnitude. Furthermore, an improvement by two orders of the test of the universality of the gravitational red shift by comparison of an atomic clock with an optical clock is projected. The tests are based on ultrastable optical cavities, an atomic clock and a comb generator.

Abstract:
We show the compatibility of the theory of special relativity with the absolute reference frame with a longitudinal Doppler shift. Using two absolute velocities vA and vS, the relative velocity u is derived. Thereafter the Doppler frequency is derived using the relative velocity u. We also show the method for detecting the absolute reference frame. The representation of the theory of special relativity using the absolute reference frame appears more intuitive than an orthodox interpretation.

Abstract:
In this research-paper, many of the general-relativity-tests such as bending of light near a star and gravitational red/blue shift are explained without general-relativity & even without Newtonian-approach. The authors first raise questions on the validity of both, the Newtonian and the relativistic approach; and then propose a novel alternative-explanation. The new alternative explanation is based on refraction-phenomenon of optics. Estimation of results with new approach are in agreement with known values. Though physics is different, but it is argued that general-relativity based gravitational-bending and refraction based bending have more in common than is generally realized. Also discussed are black-hole and gravitational-lensing in the new perspective of refraction. The new refraction-based theory makes a few new predictions and also suggests a few tests.

Abstract:
The
author will show that neither the Schwarzschild metric nor the metric
introduced in 1916 by Schwarzschild describes the data produced by the time
delay experiment by Shapiro et al.
The author will describe the physical metric that will explain the time delay
experiment data correctly as a solution to Einstein Equation of General
Relativity. Other tests of General Relativity, the bending of light, the
advancement of perihelia, gravitational red shift and gravitational lensing are
satisfied by both the Schwarzschild metric and author’s physical metric.