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Related papers: Joining Spacetimes on Fractal Hypersurfaces

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We present a toy model for extending the Friedmann equations of relativistic cosmology using fractional derivatives. We do this by replacing the integer derivatives, in a few well-known cosmological results with fractional derivatives…

General Relativity and Quantum Cosmology · Physics 2021-01-25 E. Barrientos , S. Mendoza , P. Padilla

We consider cosmological models based on the spectral action formulation of (modified) gravity. We analyze the coupled effects, in this model, of the presence of nontrivial cosmic topology and of fractality in the large scale structure of…

General Relativity and Quantum Cosmology · Physics 2022-08-31 Pedro Guicardi , Matilde Marcolli

In this paper the generalisation of previous author's formulation of fractional continuum mechanics to the case of anisotropic non-locality is presented. The considerations include the review of competitive formulations available in…

Mathematical Physics · Physics 2023-08-03 Wojciech Sumelka

An abstract mathematical concept of fractal organization of certain complex objects received significant attention in astrophysics during last decades. The concept evolved into a broad field including multi-fractality and intermittency,…

Solar and Stellar Astrophysics · Physics 2013-05-24 Valentina I. Abramenko

The change of the effective dimension of spacetime with the probed scale is a universal phenomenon shared by independent models of quantum gravity. Using tools of probability theory and multifractal geometry, we show how dimensional flow is…

High Energy Physics - Theory · Physics 2012-08-16 Gianluca Calcagni

A new formalism is presented for finding equilibrium distribution functions for axisymmetric systems. The formalism, obtainded by using the concept of fractional derivatives, generalizes the methods of Fricke (1952), Kalnajs (1972) and…

Astrophysics · Physics 2009-06-14 Juan F. Pedraza , Javier Ramos-Caro , Guillermo A. Gonzalez

Generalized symmetries (also known as categorical symmetries) is a newly developing technique for studying quantum field theories. It has given us new insights into the structure of QFT and many new powerful tools that can be applied to the…

High Energy Physics - Phenomenology · Physics 2023-06-06 T. Daniel Brennan , Sungwoo Hong

A formalism and its numerical implementation is presented which allows to calculate quantities determining the spacetime structure in the large directly. This is achieved by conformal techniques by which future null infinity ($\Scri{}^+$)…

General Relativity and Quantum Cosmology · Physics 2010-11-01 Peter Huebner

We show that universal functions play an important role in the observation of the fractal structure of space--time in the numerical simulation of quantum gravity.

High Energy Physics - Theory · Physics 2007-05-23 Yoshiyuki Watabiki

The Israel junction conditions of a thin shell in the context of Einstein-Cartan gravity are revisited. It is shown that with a choice of the torsion discontinuity taken to be orthogonal to the hypersurface and consistent with the…

General Relativity and Quantum Cosmology · Physics 2020-07-15 S. Khakshournia , R. Mansouri

A mathematical method for constructing fractal curves and surfaces, termed the $p\lambda n$ fractal decomposition, is presented. It allows any function to be split into a finite set of fractal discontinuous functions whose sum is equal…

Statistical Mechanics · Physics 2015-12-15 Vladimir Garcia-Morales

Algebras of generalized functions offer possibilities beyond the purely distributional approach in modelling singular quantities in non-smooth differential geometry. This article presents an introductory survey of recent developments in…

Functional Analysis · Mathematics 2007-05-23 Michael Kunzinger

We initiate an investigation into whether fractional calculus, with its intrinsic long-tailed memory and nonlocal features, can provide a viable model for gravitational-wave memory effects. We consider two toy constructions: ($i$) a…

General Relativity and Quantum Cosmology · Physics 2026-04-01 Sercan Kaya , Bayram Tekin

We introduce a general notion of fractional (noninteger) derivative for functions defined on arbitrary time scales. The basic tools for the time-scale fractional calculus (fractional differentiation and fractional integration) are then…

Classical Analysis and ODEs · Mathematics 2014-12-05 Nadia Benkhettou , Artur M. C. Brito da Cruz , Delfim F. M. Torres

Deformations of spacelike hypersurfaces in space-time play an important role in discussions of general covariance and slicing independence in gravitational theories. In a canonical formulation, they provide the geometrical meaning of gauge…

General Relativity and Quantum Cosmology · Physics 2025-07-22 Martin Bojowald , Erick I. Duque , Aiden Shah

In this paper, we extend the principles of Nambu mechanics by incorporating fractal calculus. This extension introduces Hamiltonian and Lagrangian mechanics that incorporate fractal derivatives. By doing so, we broaden the scope of our…

General Mathematics · Mathematics 2024-03-19 Alireza Khalili Golmankhaneh , Cemil Tunç , Davron Aslonqulovich Juraev

We describe a novel fluctuating-surface current formulation of radiative heat transfer between bodies of arbitrary shape that exploits efficient and sophisticated techniques from the surface-integral-equation formulation of classical…

Materials Science · Physics 2015-06-15 Alejandro W. Rodriguez , M. T. Homer Reid , Steven G. Johnson

Hyperspaces form a powerful tool in some branches of mathematics: lots of fractal and other geometric objects can be viewed as fixed points of some functions in suitable hyperspaces - as well as interesting classes of formal languages in…

General Topology · Mathematics 2014-10-15 René Bartsch

We study the most general cosmological model with real scalar field which is minimally coupled to gravity. Our calculations are based on Friedmann-Lemaitre-Robertson-Walker (FLRW) background metric. Field equations consist of three…

General Relativity and Quantum Cosmology · Physics 2023-03-22 Medine Ildes , Metin Arik

This paper presents a comprehensive analysis of junction conditions for gluing different $f(R)$ gravitational theories across a non-null hypersurface. Using the variational approach, we systematically derive the junction conditions for both…

General Relativity and Quantum Cosmology · Physics 2026-01-27 Amin Aalipour , Nima Khosravi