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Related papers: Refocusing of Light Rays in Space-Time

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In present work we examine the implications on both, space-time measures and causal structure, of a generalization of the local causality postulate by asserting its validity to all motion regimes, the subluminal and superluminal ones. The…

General Relativity and Quantum Cosmology · Physics 2016-08-11 Benjamín Calvo-Mozo

In recent years it has been recognized that the hyperbolic numbers (an extension of complex numbers, defined as z=x+h*y with h*h=1 and x,y real numbers) can be associated to space-time geometry as stated by the Lorentz transformations of…

Mathematical Physics · Physics 2009-11-11 Francesco Catoni , Roberto Cannata , Vincenzo Catoni , Paolo Zampetti

This paper is a further development of the approach to weak cosmic censorship proposed by the authors in Ref. 5. We state and prove a modified version of that work's main result under significantly relaxed assumptions on the asymptotic…

General Relativity and Quantum Cosmology · Physics 2009-11-11 W. Rudnicki , R. J. Budzynski , W. Kondracki

To clarify some aspects of the application of Special Relativity, spacetime is sliced into null geodesic hypersurfaces as an alternative to the hypersurfaces of simultaneity normally adopted. Events at particle locations on the hypersurface…

General Physics · Physics 2007-05-23 Alasdair Macleod

We develop the spacetime approach to gravitational lensing by spherically symmetric perturbations of flat, cosmological constant-dominated Friedman-Robertson-Walker metrics. The geodesics of the spacetime are expressed as integral…

General Relativity and Quantum Cosmology · Physics 2025-08-19 Thomas P. Kling , Sophia MacQueen Pooler

A fundamental spacetime scale in the universe leads to noncommutative spacetime and thence to a modified energy - momentum dispersion relation or equivalently to a modification of Lorentz symmetry as shown by the author and others. This…

General Physics · Physics 2009-01-27 Burra G. Sidharth

The statement of the title is proved. It implies that under physically reasonable conditions, spacetimes which are free from singularities are necessarily stably causal and hence admit a time function. Read as a singularity theorem it…

General Relativity and Quantum Cosmology · Physics 2009-05-12 E. Minguzzi

In a recent work I showed that the family of smooth steep time functions can be used to recover the order, the topology and the (Lorentz-Finsler) distance of spacetime. In this work I present the main ideas entering the proof of the…

Differential Geometry · Mathematics 2018-02-26 E. Minguzzi

A calculus based on pointer-mark coincidences is proposed to define, in a mathematically rigorous way, measurements of space and time intervals. The connection between such measurements in different inertial frames according to the Galilean…

General Physics · Physics 2011-10-26 J. H. Field

It is rarely emphasized in modern physics textbooks that our definitions of space and time have to reflect their complete interdependence. Our intuitive methods of always picturing one-dimensional space as a sum of unit-length rods and of…

General Physics · Physics 2008-07-03 Ibrahim M. Al Abdulmohsin

The causal spacetimes admitting a covariantly constant null vector provide a connection between relativistic and non-relativistic physics. We explore this relationship in several directions. We start proving a formula which relates the…

General Relativity and Quantum Cosmology · Physics 2012-11-13 E. Minguzzi

A reflexive relation on a set can be a starting point in defining the causal structure of a spacetime in General Relativity and other relativistic theories of gravity. If we identify this relation as the relation between lightlike separated…

General Relativity and Quantum Cosmology · Physics 2016-06-07 Ovidiu Cristinel Stoica

We present a concise new definition of Finsler spacetimes that generalize Lorentzian metric manifolds and provide consistent backgrounds for physics. Extending standard mathematical constructions known from Finsler spaces we show that…

General Relativity and Quantum Cosmology · Physics 2011-08-29 Christian Pfeifer , Mattias N. R. Wohlfarth

First, we extend the special relativity into the superluminal case and put forward a superluminal theory of kinematics, in which we show that the temporal coordinate need exchanging with one of the spatial coordinates in a superluminal…

General Physics · Physics 2009-07-22 Z. C. Tu , Z. Y. Wan

The hypothesis that the Lorentz transformations may be modified at Planck scale energies is further explored. We present a general formalism for theories which preserve the relativity of inertial frames with a non-linear action of the…

General Relativity and Quantum Cosmology · Physics 2011-05-05 Joao Magueijo , Lee Smolin

An analysis of the Lorentz transformation shows that the unchangeability of the space-time coordinates of the inertial systems under consideration and the possibility of a direct projection of those coordinates onto another are the…

General Physics · Physics 2007-05-23 Ernst Karl Kunst

The two closely related Lorentz-invariant partial orders of space-time are distinguished with respect to the existence of antichain cutsets and the possibility of grading. World lines of particles with or without mass are the maximal chains…

Mathematical Physics · Physics 2018-02-27 Stephan Foldes

In this work we revisit the notion of the (future) causal completion of a globally hyperbolic spacetime and endow it with the structure of a Lorentzian pre-length space. We further carry out this construction for a certain class of…

General Relativity and Quantum Cosmology · Physics 2022-09-28 L. Ake Hau , Saul Burgos , Didier A. Solis

We present a deductive theory of space-time which is realistic, objective, and relational. It is realistic because it assumes the existence of physical things endowed with concrete properties. It is objective because it can be formulated…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Santiago E. Perez Bergliaffa , Gustavo E. Romero , Hector Vucetich

It is shown that the problem of a possible violation of the Lorentz transformations at Lorentz factors $\gamma >5\times 10^{10} ,$ indicated by the situation which has developed in the physics of ultra-high energy cosmic rays (the absence…

General Relativity and Quantum Cosmology · Physics 2015-06-25 G. Yu. Bogoslovsky , H. F. Goenner