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We propose a new approach to the Cosmological Constant Problem which makes essential use of an extra dimension. A model is presented in which the Standard Model vacuum energy ``warps'' the higher-dimensional spacetime while preserving 4D…

High Energy Physics - Theory · Physics 2009-09-15 Nima Arkani-Hamed , Savas Dimopoulos , Nemanja Kaloper , Raman Sundrum

We develop a new concept of non-positive curvature for metric spaces, based on intersection patterns of closed balls. In contrast to the synthetic approaches of Alexandrov and Buesemann, our concept also applies to metric spaces that might…

Metric Geometry · Mathematics 2020-01-29 Parvaneh Joharinad , Jürgen Jost

The exact solution for dynamic of conform-flat space homogeneous since dynamic equation is given. Conform mode of space metric changing in Global time theory has negative energy density. Swap of energy to this mode from another ones lead to…

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

In this paper we study the viability of an entropic cosmological model. The effects of entropic gravity are derived from a modified entropy-area relationship with a volumetric entropy term. This model describes a late time limit cosmic…

General Relativity and Quantum Cosmology · Physics 2024-03-07 Javier Chagoya , I. Díaz-Saldaña , J. C. López-Domínguez , M. Sabido

The cosmographic approach, which only relies upon the homogeneity and isotropy of the Universe on large scales, has become an essential tool in dealing with an increasing number of theoretical possibilities for explaining the late-time…

General Relativity and Quantum Cosmology · Physics 2016-04-26 Alvaro de la Cruz-Dombriz

In this paper, an estimation of lower bound of topological entropy for coupled-expanding systems associated with transition matrices in compact Hausdorff spaces is given. Estimations of upper and lower bounds of topological entropy for…

Dynamical Systems · Mathematics 2015-06-04 Hua Shao , Yuming Shi , Hao Zhu

The quantum contributions to the gravitational action are relatively easy to calculate in the higher derivative sector of the theory. However, the applications to the post-inflationary cosmology and astrophysics require the corrections to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Julio C. Fabris , Paulo L. C. de Oliveira , Davi C. Rodrigues , Ilya L. Shapiro , A. M. Velasquez-Toribio

Multi-connected universe models with space identification scales smaller than the size of the observable universe produce topological images of cosmic sources. We generalise to locally hyperbolic spaces the crystallographic method, aimed to…

Astrophysics · Physics 2011-05-23 Jean-Philippe Uzan , Roland Lehoucq , Jean-Pierre Luminet

A non-linear gravitational model with a multidimensional geometry and quadratic scalar curvature is considered. For certain parameter ranges, the extra dimensions are stabilized if the internal spaces have negative curvature. As a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 U. Guenther , P. Moniz , A. Zhuk

We consider a general n dimensional manifold, which is a direct product manifold of $M^4 \times M^{n-4}$ representing our universe and extra spatial dimensions. From Einstein-Hilbert action of the manifold, we deduce effective 4 dimensional…

General Relativity and Quantum Cosmology · Physics 2014-05-01 Yong-Chang Huang , LiuJi Li

We investigate late time acceleration of the universe in higher dimensional cosmology. The content in the universe is assumed to exert pressure which is different in the normal and extra dimensions. Cosmologically viable solutions are found…

General Relativity and Quantum Cosmology · Physics 2011-09-29 Isha Pahwa , Debajyoti Choudhury , T. R. Seshadri

We propose a theory for coupling matter fields with discrete geometry on higher-order networks, i.e. cell complexes. The key idea of the approach is to associate to a higher-order network the quantum entropy of its metric. Specifically we…

Disordered Systems and Neural Networks · Physics 2024-09-12 Ginestra Bianconi

Effective 4-dimensional theories are investigated which were obtained under dimensional reduction of multidimensional cosmological models with a minimal coupled scalar field as matter source. Conditions for the internal space stabilization…

High Energy Physics - Phenomenology · Physics 2009-10-31 U. Guenther , A. Zhuk

Most of the calculations done to obtain the value of the cosmological constant use methods of quantum gravity, a theory that has not been established as yet, and a variety of results are usually obtained. The numerical value of the…

Astrophysics · Physics 2007-05-23 Moshe Carmeli

In this article, we construct explicit analytical exact solutions to the six and higher dimensional Einstein-Maxwell theory. In all solutions, a subspace of the metric is the Eguchi-Hanson space where the metric functions are completely…

General Relativity and Quantum Cosmology · Physics 2017-09-28 A. M. Ghezelbash , V. Kumar

We study a cosmological model in 1+D+d dimensions where D dimensions are associated with the usual Friedman-Robertson-Walker type metric with radio a(t) and d dimensions corresponds to an additional homogeneous space with radio b(t). We…

General Relativity and Quantum Cosmology · Physics 2011-04-20 E. A. Leon , J. A. Nieto , R. Nunez-Lopez , A. Lipovka

Many inverse problems in nuclear fusion and high-energy astrophysics research, such as the optimization of tokamak reactor geometries or the inference of black hole parameters from interferometric images, necessitate high-dimensional…

Machine Learning · Computer Science 2025-05-09 Jonathan Gorard , Ammar Hakim , Hong Qin , Kyle Parfrey , Shantenu Jha

In this paper we perform systematic investigation of all possible solutions with static compact extra dimensions and expanding three-dimensional subspace (``our Universe''). Unlike previous papers, we consider extra-dimensional subspace to…

General Relativity and Quantum Cosmology · Physics 2021-04-22 Dmitry Chirkov , Alex Giacomini , Sergey A. Pavluchenko , Alexey Toporensky

The tensions between the values of Hubble constant obtained from the early and the late Universe data pose a significant challenge to modern cosmology. Possible modifications of the flat homogeneous isotropic cosmological {\Lambda}CDM model…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-14 S. L. Parnovsky

One of the principal difficulties in stochastic homogenization is transferring quantitative ergodic information from the coefficients to the solutions, since the latter are nonlocal functions of the former. In this paper, we address this…

Analysis of PDEs · Mathematics 2017-06-07 Scott Armstrong , Tuomo Kuusi , Jean-Christophe Mourrat