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Related papers: Deformed spaces and loop cosmology

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We investigate the cosmology of a recently proposed deformation of Einstein gravity, emerging from quantum gravity heuristics. The theory is constructed to have de Sitter space as a vacuum solution, and thus to be relevant to the…

The classical $r$-matrix for $N=1$ superPoincar{\'e} algebra, given by Lukierski, Nowicki and Sobczyk is used to describe the graded Poisson structure on the $N=1$ Poincar{\'e} supergroup. The standard correspondence principle between the…

High Energy Physics - Theory · Physics 2019-08-15 P. Kosi{ń}ski , J. Lukierski , P. Ma{ś}lanka , J. Sobczyk

We investigate a particular type of classical nonsingular bouncing cosmology, which results from general relativity if we allow for degenerate metrics. The simplest model has a matter content with a constant equation-of-state parameter and…

General Relativity and Quantum Cosmology · Physics 2019-10-23 F. R. Klinkhamer , Z. L. Wang

Starting from deformed quantum Heisenberg Lie algebras some realizations are given in terms of the usual creation and annihilation operators of the standard harmonic oscillator. Then the associated algebra eigenstates are computed and give…

Mathematical Physics · Physics 2007-05-23 Nibaldo Alvarez-Moraga

A differential calculus, differential geometry and the E-R Gravity theory are studied on noncommutative spaces. Noncommutativity is formulated in the star product formalism. The basis for the gravity theory is the infinitesimal algebra of…

High Energy Physics - Theory · Physics 2008-12-19 Julius Wess

The quantum duality principle is used to obtain explicitly the Poisson analogue of the kappa-(A)dS quantum algebra in (3+1) dimensions as the corresponding Poisson-Lie structure on the dual solvable Lie group. The construction is fully…

High Energy Physics - Theory · Physics 2017-01-19 Angel Ballesteros , Francisco J. Herranz , Fabio Musso , Pedro Naranjo

We study the most elementary aspects of harmonic analysis on a homogeneous space of a deformation of the two-dimensional Euclidean group, admitting generalizations to dimensions three and four, whose quantum parameter has the physical…

q-alg · Mathematics 2008-02-03 F. Bonechi , R. Giachetti , M. A. del Olmo , E. Sorace , M. Tarlini

We review shortly present status of quantum deformations of Poincar\'{e} and conformal supersymmetries. After recalling the $\kappa$-deformation of $\hbox{D=4}$ Poincar\'{e} supersymmetries we describe the corresponding star product…

High Energy Physics - Theory · Physics 2007-05-23 P. Kosinski , J. Lukierski , P. Maslanka

We apply Lie algebra deformation theory to the problem of identifying the stable form of the quantum relativistic kinematical algebra. As a warm up, given Galileo's conception of spacetime as input, some modest computer code we wrote zeroes…

High Energy Physics - Theory · Physics 2009-11-10 C. Chryssomalakos , E. Okon

We propose a Hamiltonian formalism for a generalized Friedmann-Roberson-Walker cosmology model in the presence of both a variable equation of state (EOS) parameter $w(a)$ and a variable cosmological constant $\Lambda(a)$, where $a$ is the…

High Energy Physics - Theory · Physics 2008-11-26 Jie Ren , Xin-He Meng , Liu Zhao

Considering space--time to be non-commutative, we study the evolution of the universe employing the approach of Newtonian cosmology. Generalizing the conservation of energy and the first law of thermodynamics to $\kappa$-deformed…

General Relativity and Quantum Cosmology · Physics 2023-07-31 E. Harikumar , Harsha Sreekumar , Suman Kumar Panja

In this letter a new formula for light deflection is derived using only physically observable concepts. The general result is specialized to cosmological perturbation theory and expressed in terms of gauge--invariant perturbation variables.…

Astrophysics · Physics 2009-10-22 Ruth Durrer

Braneworld cosmology for a domain wall embedded in the charged (Anti)-de Sitter-Schwarzschildblack hole of the five--dimensional Einstein-Gauss-Bonnet-Maxwell theory is considered. The effective Friedmann equation for the brane is derived…

High Energy Physics - Theory · Physics 2009-11-07 James E. Lidsey , Shin'ichi Nojiri , Sergei D. Odintsov

Within the framework of loop quantum cosmology, there exists a semi-classical regime where spacetime may be approximated in terms of a continuous manifold, but where the standard Friedmann equations of classical Einstein gravity receive…

General Relativity and Quantum Cosmology · Physics 2009-11-10 James E. Lidsey

Considering quantum cosmological minisuperspace models with positive potential, we present evidence that (i) despite common belief there are perspectives for defining a unique, naturally preferred decomposition of the space H of wave…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Franz Embacher

We quantize spherically symmetric vacuum gravity without gauge fixing the diffeomorphism constraint. Through a rescaling, we make the algebra of Hamiltonian constraints Abelian and therefore the constraint algebra is a true Lie algebra.…

General Relativity and Quantum Cosmology · Physics 2013-12-18 Rodolfo Gambini , Jorge Pullin

In the framework of loop quantum gravity, we define a new Hilbert space of states which are solutions of a large number of components of the diffeomorphism constraint. On this Hilbert space, using the methods of Thiemann, we obtain a family…

General Relativity and Quantum Cosmology · Physics 2015-03-05 Jerzy Lewandowski , Hanno Sahlmann

Considering as usual that the underlying geometry of our universe is well described by the spatially flat Friedmann-Lemaitre-Robertson-Walker line element, we review how the background of holonomy corrected Loop Quantum Cosmology (LQC)…

General Relativity and Quantum Cosmology · Physics 2019-05-01 Jaume de Haro , Llibert Aresté Saló , Supriya Pan

The noncommutativity of the space-time had important implications for the very early Universe, when its size was of the order of the Planck length. An important implication of this effect is the deformation of the standard dispersion…

General Relativity and Quantum Cosmology · Physics 2018-10-09 Yunxin Ye , Tiberiu Harko , Shi-Dong Liang

We point out that aspects of quantum mechanics can be derived from the holographic principle, using only a perturbative limit of classical general relativity. In flat space, the covariant entropy bound reduces to the Bekenstein bound. The…

High Energy Physics - Theory · Physics 2014-11-18 Raphael Bousso
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