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A multidimensional cosmology with FRW type metric having 4-dimensional space-time and $d$-dimensional Ricci-flat internal space is considered with a higher dimensional cosmological constant. The classical cosmology in commutative and…

General Relativity and Quantum Cosmology · Physics 2013-04-25 K. Zeynali , F. Darabi , H. Motavalli

The prime number decomposition of a finite dimensional Hilbert space reflects itself in the representations that the space accommodates. The representations appear in conjugate pairs for factorization to two relative prime factors which can…

Quantum Physics · Physics 2009-11-13 M. Revzen , F. C. Khanna

Cosmography is a phenomenological and relatively model-independent approach to cosmology, where physical quantities are expanded as a Taylor series in the cosmological redshift, or in related variables. Here we apply this methodology to…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-08 C. J. A. P. Martins , F. P. S. A. Ferreira , P. V. Marto

In this letter we study the effects of a noncommutative in the phase space of an empty (4+1) Kaluza-Klein universe with cosmological constant. We analyze the effects of the noncommutative deformations on the cosmological constant. Finally…

High Energy Physics - Theory · Physics 2013-07-09 E. Mena , S. Pérez-Payán , M. Sabido

We examine the phase space of Ho\v{r}ava-Lifshitz cosmology for a wide range of self-interacting potentials for the scalar field under the detailed-balance condition and without imposing it, by means of the powerful method of $f$-devisers.…

General Relativity and Quantum Cosmology · Physics 2019-08-27 Genly Leon , Andronikos Paliathanasis

The effects of phase space deformations on Kalutza-Klein cosmology are studied. The deformation is introduced by modifying the symplectic structure of the minisuperspace variables. In the deformed model, we find an accelerating scale factor…

General Relativity and Quantum Cosmology · Physics 2016-03-30 M. Sabido , C. Yee-Romero

We perform a Hamiltonian reduction of spherically symmetric Einstein gravity with a thin dust shell of positive rest mass. Three spatial topologies are considered: Euclidean (R^3), Kruskal (S^2 x R), and the spatial topology of a…

General Relativity and Quantum Cosmology · Physics 2014-11-17 John L. Friedman , Jorma Louko , Stephen N. Winters-Hilt

Spatially homogeneous cosmological models with a positive cosmological constant are investigated, using dynamical systems methods. We focus on the future evolution of these models. In particular, we address the question whether there are…

General Relativity and Quantum Cosmology · Physics 2011-07-18 Martin Goliath , George F. R. Ellis

In three spacetime dimensions, general relativity drastically simplifies, becoming a ``topological'' theory with no propagating local degrees of freedom. Nevertheless, many of the difficult conceptual problems of quantizing gravity are…

General Relativity and Quantum Cosmology · Physics 2015-06-25 S. Carlip

We deduce the appearance of a polymeric phase in 4-dimensional simplicial quantum gravity by varying the values of the coupling constants and discuss the geometric structure of the phase in terms of ergodic moves. A similar result is true…

High Energy Physics - Lattice · Physics 2009-10-30 Davide Gabrielli

In this paper we perform a systematic classification of the regimes of cosmological dynamics in Einstein-Gauss-Bonnet gravity with generic values of the coupling constants. We consider a manifold which is a warped product of a four…

General Relativity and Quantum Cosmology · Physics 2014-12-17 Fabrizio Canfora , Alex Giacomini , Sergey A. Pavluchenko

We consider extra compact dimensions as the origin of a cosmological universal energy density in the regular dimensions, with only graviton fields propagating in the compact space dimensions. The quantum zero point energy originating from…

General Relativity and Quantum Cosmology · Physics 2015-09-03 Vikram Soni , Naresh Dadhich , Rathin Adhikari

Ashtekar and Samuel have shown that Bianchi cosmological models with compact spatial sections must be of Bianchi class A. Motivated by general results on the symmetry reduction of variational principles, we show how to extend the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 C. G. Torre

We assume that the points in volumes smaller than an elementary volume (which may have a Planck size) are indistinguishable in any physical experiment. This naturally leads to a picture of a discrete space with a finite number of degrees of…

High Energy Physics - Theory · Physics 2026-01-07 Ali H. Chamseddine , Viatcheslav Mukhanov

We present the basic formulation of Hamilton dynamics in complex phase space. We extend the Hamilton's function by including the imaginary part and find out the corresponding Hamilton's canonical equation of motion. Example of simple…

Classical Physics · Physics 2019-06-18 Muhammad Adnan Shahzad

The observable universe has undergone periods of expansion that are well approximated by de Sitter (dS) space. Still lacking is a quantum mechanical description of dS, both globally and when restricted to the static patch. We develop a…

High Energy Physics - Theory · Physics 2025-08-15 Vyshnav Mohan , Watse Sybesma

Multidimensional cosmological model with static internal spaces describing the evolution of an Einstein space of non-zero curvature and n internal spaces is considered. The action contains several dilatonic scalar fields and antisymmetric…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. A. Grebeniuk , V. D. Ivashchuk , V. N. Melnikov

We study some aspects of dynamical compactification scenario where stabilisation of extra dimensions occurs due to presence the Gauss-Bonnet term and non-zero spatial curvature. In the framework of the model under consideration there exists…

General Relativity and Quantum Cosmology · Physics 2021-05-12 Dmitry Chirkov , Sergey A. Pavluchenko

We present classical and quantum dynamics of a test particle in the compactified Milne space. Background spacetime includes one compact space dimension undergoing contraction to a point followed by expansion. Quantization consists in…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Przemyslaw Malkiewicz , Wlodzimierz Piechocki

Cosmography is a model-independent phenomenological approach to observational cosmology, relying on Taylor series expansions of physical quantities as a function of the cosmological redshift or other analogous variables. A recent work…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-27 C. J. A. P. Martins