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Related papers: Multiscale spacetimes from first principles

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We provide a self-contained exposition of the well-known multifractal formalism for self-similar measures satisfying the strong separation condition. At the heart of our method lies a pair of quasiconvex optimization problems which encode…

Dynamical Systems · Mathematics 2024-03-01 Alex Rutar

The space-time geometry is considered to be a physical geometry, i.e. a geometry described completely by the world function. All geometrical concepts and geometric objects are taken from the proper Euclidean geometry. They are expressed via…

General Physics · Physics 2007-05-23 Yuri A. Rylov

We review recent developments in the understanding of the fractal properties of quantum spacetime of 2d gravity coupled to c>0 conformal matter. In particular we discuss bounds put by numerical simulations using dynamical triangulations on…

High Energy Physics - Lattice · Physics 2009-10-30 J. Ambjorn , K. N. Anagnostopoulos , G. Thorleifsson

A simple multifractal coarsening model is suggested that can explain the observed dynamical behavior of the fractal dimension in a wide range of coarsening fractal systems. It is assumed that the minority phase (an ensemble of droplets) at…

Disordered Systems and Neural Networks · Physics 2009-10-31 Avner Peleg , Baruch Meerson

We clarify the relation between noncommutative spacetimes and multifractional geometries, two quantum-gravity-related approaches where the fundamental description of spacetime is not given by a classical smooth geometry. Despite their…

High Energy Physics - Theory · Physics 2017-02-06 Gianluca Calcagni , Michele Ronco

We construct the differential geometry of smooth manifolds equipped with an algebraic curvature map acting as an area measure. Area metric geometry provides a spacetime structure suitable for the discussion of gauge theories and strings,…

High Energy Physics - Theory · Physics 2009-11-11 Frederic P. Schuller , Mattias N. R. Wohlfarth

It has been recently claimed [arXiv:1102.3434] that quantum gravity models where the number of dimensions reduces at the ultraviolet exhibit a potentially observable cutoff in the primordial gravitational wave spectrum, and that this is a…

General Relativity and Quantum Cosmology · Physics 2011-10-18 Thomas P. Sotiriou , Matt Visser , Silke Weinfurtner

In this work, we explicitly construct the vacuum solution of Einstein's equations with prescribed multipole moments. By observing the behavior of the multipole spacetime metric at small distances, we conjecture that for a sufficiently large…

General Relativity and Quantum Cosmology · Physics 2024-06-24 Shammi Tahura , Hassan Khalvati , Huan Yang

In this paper we provide new methodology for inference of the geometric features of a multivariate density in deconvolution. Our approach is based on multiscale tests to detect significant directional derivatives of the unknown density at…

Methodology · Statistics 2016-11-21 Konstantin Eckle , Nicolai Bissantz , Holger Dette

In this article we study two related models of quantum geometry: generic random trees and two-dimensional causal triangulations. The Hausdorff and spectral dimensions that arise in these models are calculated and their relationship with the…

High Energy Physics - Theory · Physics 2022-11-29 Bergfinnur Durhuus , Thordur Jonsson , John Wheater

Higher dimensional solutions are obtained for a homogeneous, spatially isotropic cosmological model in Wesson theory of gravitation. Some cosmological parameter are also calculated for this model.

General Relativity and Quantum Cosmology · Physics 2007-05-23 G. S. Khadekar , Shilpa Samdurkar

Two-dimensional quantum gravity, defined either via scaling limits of random discrete surfaces or via Liouville quantum gravity, is known to possess a geometry that is genuinely fractal with a Hausdorff dimension equal to 4. Coupling…

General Relativity and Quantum Cosmology · Physics 2020-02-05 Jerome Barkley , Timothy Budd

We introduce the notion of scale to generalize and compare different invariants of metric spaces and their measures. Several versions of scales are introduced such as Hausdorff, packing, box, local and quantization. They moreover are…

Dynamical Systems · Mathematics 2025-02-11 Mathieu Helfter

Topography is the expression of both internal and external processes of a planetary body. Thus hypsometry (the study of topography) is a way to decipher the dynamic of a planet. For that purpose, the statistics of height and slopes may be…

Earth and Planetary Astrophysics · Physics 2018-10-10 François Landais , Frédéric Schmidt , Shaun Lovejoy

At present we have only the very successful but phenomenological Einstein geometrical modelling of the spacetime phenomenon. This geometrical model provides a `container' for other theories, in particular the quantum field theories. Here we…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Reginald T. Cahill , Christopher M. Klinger

Attention is focused on antisymmetrized versions of quantum spaces that are of particular importance in physics, i.e. two-dimensional quantum plane, q-deformed Euclidean space in three or four dimensions as well as q-deformed Minkowski…

High Energy Physics - Theory · Physics 2014-11-18 Dzo Mikulovic , Alexander Schmidt , Hartmut Wachter

We introduce a multifield dark energy model with a nonflat field-space metric, in which one field is dynamical while the others have constant spatial gradients. The model is predictive at the background level, leading to an early dark…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-04 Juan P. Beltrán Almeida , Alejandro Guarnizo , Thiago S. Pereira , César A. Valenzuela-Toledo

A class of simplified measures is constructed to capture the key features of generic spatio-temporally chaotic systems. A combined analytical and numerical investigation allows us to extablish the scaling beahviour of the fractal dimension…

chao-dyn · Physics 2009-10-31 Antonio Politi , Annette Witt

We consider systems of multiple Brownian particles in one dimension that repel mutually via a logarithmic potential on the real line, more specifically the Dyson model. These systems are characterized by a parameter that controls the…

Probability · Mathematics 2023-02-22 Nicole Hufnagel , Sergio Andraus

In this paper we propose methods for inference of the geometric features of a multivariate density. Our approach uses multiscale tests for the monotonicity of the density at arbitrary points in arbitrary directions. In particular, a…

Statistics Theory · Mathematics 2016-04-18 Konstantin Eckle , Nicolai Bissantz , Holger Dette , Katharina Proksch , Sabrina Einecke
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