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Related papers: Scale-dependent homogeneity measures for causal dy…

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We probe the angular scale of homogeneity in the local Universe using blue galaxies from the SDSS survey as a cosmological tracer. Through the scaled counts in spherical caps, $ \mathcal{N}(<\theta) $, and the fractal correlation dimension,…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-10 F. Avila , C. P. Novaes , A. Bernui , E. de Carvalho , J. P. Nogueira-Cavalcante

Motivated by the search for new observables in nonperturbative quantum gravity, we consider Causal Dynamical Triangulations (CDT) in 2+1 dimensions with the spatial topology of a torus. This system is of particular interest, because one can…

High Energy Physics - Theory · Physics 2013-07-11 T. G. Budd , R. Loll

If an effect measure is more homogeneous than others, then its value is more likely to be stable across different subgroups or subpopulations. Therefore, it is of great importance to find a more homogeneous effect measure that allows for…

Statistics Theory · Mathematics 2015-11-10 Peng Ding , Tyler J. VanderWeele

We explore the phenomenological implications of generalizing measures to a multidimensional multiverse. We consider a simple model in which the vacua are nucleated from a $D$-dimensional parent spacetime through dynamical compactification…

High Energy Physics - Theory · Physics 2015-04-29 Hyeyoun Chung

The physical origin of spacetime discreteness remains a central open problem in quantum gravity, with most existing approaches relying on specific microscopic structures or model-dependent assumptions. In this letter, spacetime discreteness…

General Relativity and Quantum Cosmology · Physics 2026-05-26 Weihu Ma , Yu-Gang Ma

The scaling of the spatio-temporal response of coarsening systems is studied through simulations of the 2D and 3D Ising model with Glauber dynamics. The scaling functions agree with the prediction of local scale invariance, extending…

Statistical Mechanics · Physics 2016-08-31 Malte Henkel , Michel Pleimling

We investigate the impact of spatial topology in 3+1 dimensional causal dynamical triangulations (CDT) by performing numerical simulations with toroidal spatial topology instead of the previously used spherical topology. In the case of…

High Energy Physics - Theory · Physics 2016-08-17 Jan Ambjorn , Zbigniew Drogosz , Jakub Gizbert-Studnicki , Andrzej Goerlich , Jerzy Jurkiewicz , Daniel Nemeth

We show that the uncertainty in distance and time measurements found by the heuristic combination of quantum mechanics and general relativity is reproduced in a purely classical and flat multi-fractal spacetime whose geometry changes with…

High Energy Physics - Theory · Physics 2017-09-22 Gianluca Calcagni , Michele Ronco

We discuss some perturbative techniques suitable for the gauge-invariant treatment of the scalar and tensor inhomogeneities of an anisotropic and homogeneous background geometry whose spatial section naturally decomposes into the direct…

High Energy Physics - Theory · Physics 2009-10-30 Massimo Giovannini

We introduce a statistical quantity, known as the $K$ function, related to the integral of the two--point correlation function. It gives us straightforward information about the scale where clustering dominates and the scale at which…

We report measurements of conditional Eulerian and Lagrangian structure functions in order to assess the effects of non-universal properties of the large scales on the small scales in turbulence. We study a 1m $\times$ 1m $\times$ 1.5m flow…

Fluid Dynamics · Physics 2015-05-13 Daniel B. Blum , Surendra Kunwar , James Johnson , Greg A. Voth

We discuss the effect of curvature and matter inhomogeneities on the averaged scalar curvature of the present-day Universe. Motivated by studies of averaged inhomogeneous cosmologies, we contemplate on the question whether it is sensible to…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Thomas Buchert , Mauro Carfora

We evaluate the spectral dimension in causal set quantum gravity by simulating random walks on causal sets. In contrast to other approaches to quantum gravity, we find an increasing spectral dimension at small scales. This observation can…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Astrid Eichhorn , Sebastian Mizera

We address measurement-based generation of quantum coherence in continuous variable systems. We consider Gaussian measurements performed on Gaussian states and focus on two scenarios. In the first one, we assume an initially correlated…

Quantum Physics · Physics 2017-08-14 Francesco Albarelli , Marco G. Genoni , Matteo G. A. Paris

We demonstrate that testing for self-similarity in scale-free simulations provides an excellent tool to quantify the resolution at small scales of cosmological N-body simulations. Analysing two-point correlation functions measured in…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-22 Michael Joyce , Lehman Garrison , Daniel Eisenstein

In the last years there has been a growing interest in the understanding a vast variety of scale invariant and critical phenomena occurring in nature. Experiments and observations indeed suggest that many physical systems develop…

Astrophysics · Physics 2019-08-17 L. Pietronero , F. Sylos Labini , M. Montuori

Several new geometric quantile-based measures for multivariate dispersion, skewness, kurtosis, and spherical asymmetry are defined. These measures differ from existing measures, which use volumes and are easy to calculate. Some theoretical…

Statistics Theory · Mathematics 2024-12-30 Ha-Young Shin , Hee-Seok Oh

The degrees of quantum coherence of cosmological perturbations of different spins are computed in the large-scale limit and compared with the standard results holding for a single mode of the electromagnetic field in an optical cavity. The…

General Relativity and Quantum Cosmology · Physics 2017-11-09 Massimo Giovannini

We review a recently discovered continuum limit for the one-matrix model which describes "causal" two-dimensional quantum gravity. The behaviour of the quantum geometry in this limit is different from the quantum geometry of Euclidean…

High Energy Physics - Theory · Physics 2009-02-05 J. Ambjorn , R. Loll , Y. Watabiki , W. Westra , S. Zohren

We use the scaled counts in spherical caps $\mathcal{N}(<\theta)$ and the fractal correlation dimension $ \mathcal{D}_{2}(\theta) $ procedures to search for a transition scale to homogeneity in the local universe as given by the ALFALFA…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-27 F. Avila , C. P. Novaes , A. Bernui , E. de Carvalho