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The fact that in Minkowski space, space and time are both quantized does not have to be introduced as a new postulate in physics, but can actually be derived by combining certain features of General Relativity and Quantum Mechanics. This is…

General Relativity and Quantum Cosmology · Physics 2007-05-23 G. 't Hooft

As the velocity of a rocket in a circular orbit near a black hole increases, the outwardly directed rocket thrust must increase to keep the rocket in its orbit. This feature might appear paradoxical from a Newtonian viewpoint, but we show…

General Relativity and Quantum Cosmology · Physics 2010-11-11 Rickard Jonsson

In this work we study the spectral dimensionality of spacetime around a radiating Schwarzschild black hole using a recently introduced formalism of quantum gravity, where the alterations of the gravitational field produced by the radiation…

General Relativity and Quantum Cosmology · Physics 2025-05-07 Mauricio Bellini , Juan Ignacio Musmarra , Pablo Alejandro Sanchez , Alan Sebastian Morales

The case of asymptotic Minkowskian space-times is considered. A special class of asymptotic rectilinear coordinates at the spatial infinity, related to a specific system of free falling observers, is chosen. This choice is applied in…

General Relativity and Quantum Cosmology · Physics 2013-05-17 Ramon Lapiedra , Juan Antonio Morales-Lladosa

We review model independent arguments showing that massless particles interacting with gravity in a Minkowski background space can have at most spin two. These arguments include a classic theorem due to Weinberg, as well as a more recent…

High Energy Physics - Theory · Physics 2012-10-09 M. Porrati

The Einstein theories of space-time and gravity as well the stander cosmology are reconstructed thoroughly in this paper based on flat reference frame. The rational parts of the Einstein theories are reserved while the irrational parts…

General Physics · Physics 2007-05-23 Mei Xiaochun

An accelerating Rindler frame in Minkowski spacetime acting for a finite time interval is used to carry a box of particles or waves between two relativistic inertial frames. The finite spatial extent of the box allows treatment of the…

Classical Physics · Physics 2026-01-19 Timothy H Boyer

We prove a globally hyperbolic spacetime with locally Lipschitz continuous metric and timelike distributional Ricci curvature bounded from below obeys the timelike measure contraction property. The remarkable class of examples of spacetimes…

Differential Geometry · Mathematics 2026-03-26 Mathias Braun , Marta Sálamo Candal

The conventional discussion of apparent distortions of space and time in Special Relativity (the Lorentz-Fitzgerald Contraction and Time Dilatation) is extended by considering observations of : (i) moving objects of limited lifetime in…

Popular Physics · Physics 2009-10-01 J. H. Field

In the rod and hole paradox as described by Rindler (1961 Am. J. Phys. 29 365-6), a rigid rod moves at high speed over a table towards a hole of the same size. Observations from the inertial frames of the rod and slot are widely different.…

Classical Physics · Physics 2008-09-11 Chandru Iyer , G. M. Prabhu

In this paper I argue for a reassessment of special relativity. The fundamental theory of relativity applicable in this Universe has to be consistent with the existence of the massive Universe, and with the effects of its gravitational…

General Relativity and Quantum Cosmology · Physics 2007-05-23 C. S. Unnikrishnan

In this paper, we aim to resolve two fundamental issues in the dynamics of relativity: (i) Under what condition, the time-column space integrals of a Lorentz four-tensor constitute a Lorentz four-vector, and (ii) under what condition, the…

General Physics · Physics 2020-12-04 Changbiao Wang

In deformed or doubly special relativity (DSR) the action of the lorentz group on momentum eigenstates is deformed to preserve a maximal momenta or minimal length, supposed equal to the Planck length. The classical and quantum dynamics of a…

General Relativity and Quantum Cosmology · Physics 2015-05-18 Lee Smolin

It was shown by Tsallis and Cirto that thermodynamical entropy of a gravitational system such as black hole must be generalized to the non-additive entropy, which is given by $S_h=\gamma A^{\beta}$, where $A$ is the horizon area and $\beta$…

General Relativity and Quantum Cosmology · Physics 2018-09-26 Ahmad Sheykhi

This paper investigates the motion of a rotating test body in the Schwarzschild space-time. After reduction, this problem reduces to an analysis of a three-degree-of-freedom. Hamiltonian system whose desired trajectories lie on the…

Dynamical Systems · Mathematics 2026-02-12 Ivan Bizyaev

We consider a two-time (characterized by distinct speeds of causality) and three-space-dimensional Minkowski space and derive relativistic coordinate and velocity transformation formulas and expressions for a new effective speed limit.…

General Physics · Physics 2023-11-16 Sajjad Zahir

The Ehrenfest paradox for a rotating ring is examined and a kinematic resolution, within the framework of the special theory of relativity, is presented. Two different ways by which a ring can be brought from rest to rotational motion,…

General Relativity and Quantum Cosmology · Physics 2024-01-25 Jitendra Kumar

Standard treatments of general relativity accept the gravitational slowing of clocks as a primary phenomenon, requiring no further analysis as to cause. Rejecting this attitude, I argue that one or more of the fundamental "constants"…

General Relativity and Quantum Cosmology · Physics 2007-05-23 John E. Heighway

This paper reviews the history and origin of the Abraham-Minkowski controversy and points out that it is a continuation of the controversy over the speed of light in medium. Upon considering an aircraft flying at a constant speed along the…

Optics · Physics 2021-04-05 Guoxu Feng , Jun Huang

Superluminal particles are not excluded by particle physics. The apparent Lorentz invariance of the laws of physics does not imply that space-time is indeed minkowskian. Matter made of solutions of Lorentz-invariant equations would feel a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Luis Gonzalez-Mestres