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Related papers: Looking at spacetime atoms from within the Lorentz…

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Given a Lorentzian spacetime $(M, g)$ and a non-vanishing timelike vector field $u(\lambda)$ with level surfaces $\Sigma$, one can construct on $M$ a Euclidean metric $g_E^{ab} = g^{ab} + 2 u^a u^b$. Motivated by this, we consider a class…

General Relativity and Quantum Cosmology · Physics 2018-01-16 Dawood Kothawala

We show that the metric (line element) is the first geometrical object to be associated to a discrete (quantum) structure of the spacetime without necessity of black hole-entropy-area arguments, in sharp contrast with other attempts in the…

High Energy Physics - Theory · Physics 2014-06-16 Diego Julio Cirilo-Lombardo , Thiago Prudencio

Recently, Horava formulated a renormalizable theory of quantum gravity that reduces to general relativity at large distances but violates Lorentz invariance at small distances. The absolute time involved in this theory allows to define an…

High Energy Physics - Theory · Physics 2014-11-18 H. Nikolic

The history of the particle concept is briefly reviewed, with particular emphasis on the `foliation dependence' of many particle creation models, and the possible connection between our notion of particle and our notion of simultaneity. It…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Carl E. Dolby

We discuss the hints for the disappearance of continuum space and time at microscopic scale. These include arguments for a discrete nature of them or for a fundamental non-locality, in a quantum theory of gravity. We discuss how these ideas…

History and Philosophy of Physics · Physics 2013-02-13 Daniele Oriti

If $a$ is a quantum effect and $\rho$ is a state, we define the $\rho$-entropy $S_a(\rho )$ which gives the amount of uncertainty that a measurement of $a$ provides about $\rho$. The smaller $S_a(\rho )$ is, the more information a…

Quantum Physics · Physics 2022-11-22 Stan Gudder

We consider a model of Quantum Gravity phenomenology, based on the idea that space-time may have some unknown granular structure that respects the Lorentz symmetry. The proposal involves non-trivial couplings of curvature to matter fields…

General Relativity and Quantum Cosmology · Physics 2008-01-21 Y. Bonder

All gauge theories need ``something fixed'' even as ``something changes.'' Underlying the implementation of these ideas all major physical theories make indispensable use of an elaborately designed spacetime model as the ``something…

General Relativity and Quantum Cosmology · Physics 2011-04-15 Carl H. Brans

In two recent papers by the author, a new approach was suggested for quantising space-time, or space. This involved developing a procedure for quantising a system whose configuration space--or history-theory analogue--is the set of objects,…

General Relativity and Quantum Cosmology · Physics 2007-05-23 C. J. Isham

We introduce a notion of Lorentzian metric space which drops the boundedness condition from our previous work and argue that the properties defining our spaces are minimal. In fact, they are defined by three conditions given by (a) the…

Metric Geometry · Mathematics 2025-05-13 A. Bykov , E. Minguzzi , S. Suhr

I present an analysis of the physical assumptions needed to obtain the metric structure of space-time. For this purpose I combine the axiomatic approach pioneered by Robb with ideas drawn from works on Weyl's "Raumproblem". The concept of a…

General Relativity and Quantum Cosmology · Physics 2010-09-29 Jochen Rau

The quantum mechanics description of a physical object stretched in space and stable in time from the relativistic space-time properties point of view, introduced in special theory of relativity, is considered and analysed. The mathematical…

Quantum Physics · Physics 2007-05-23 Andrey V. Novikov-Borodin

We develop the first steps towards an analysis of geometry on the quantum spacetime proposed in [1]. The homogeneous elements of the universal differential algebra are naturally identified with operators living in tensor powers of Quantum…

High Energy Physics - Theory · Physics 2015-03-17 Dorothea Bahns , Sergio Doplicher , Klaus Fredenhagen , Gherardo Piacitelli

Various astrophysical and cosmological observations today serve as an indirect evidence of the existence of dark matter in the universe. In the present work, we propose a class of spacetimes that show some important characteristics relevant…

General Relativity and Quantum Cosmology · Physics 2022-12-07 Ashok B. Joshi , Divya Tahelyani , Dipanjan Dey , Pankaj S. Joshi

A structured collection of thought provoking conclusions about space and time is given. Using only the Compton wavelength lambda = hbar / m c and the Schwarzschild radius r_s = 2 G m / c^2, it is argued that neither the continuity of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Christoph Schiller

The quantization of a single particle without spin in an appropriate curved space-time is considered. The Hamilton formalism on reduced space for a particle in a curved space-time is constructed and the main aspects of quantization scheme…

General Relativity and Quantum Cosmology · Physics 2007-05-23 D. A. Kalinin

This paper outlines a possibility for spacetime dynamics and structure, without postulating a metric ab initio. In this model, the closer an object is to a mass or energy source, the more paths through spacetime might be available to the…

High Energy Physics - Theory · Physics 2007-05-23 M. Dance

The appearance of linear spaces, describing physical quantities by vectors and tensors, is ubiquitous in all of physics, from classical mechanics to the modern notion of local Lorentz invariance. However, as natural as this seems to the…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Markus P. Mueller , Sylvain Carrozza , Philipp A Hoehn

We propose possible properties of quantum gravity in de Sitter space, and find that they relate the value of the cosmological constant to parameters of the Standard Model. In de Sitter space we suggest (i) that the most sharply defined…

High Energy Physics - Theory · Physics 2023-06-07 Mark P. Hertzberg , Abraham Loeb

This work interprets the quantum terms in a Lagrangian, and consequently of the wave equation and momentum tensor, in terms of a modified spacetime metric. Part I interprets the quantum terms in the Lagrangian of a Klein Gordon field as…

General Relativity and Quantum Cosmology · Physics 2022-08-24 Richard James Petti