English
Related papers

Related papers: Deformed spaces and loop cosmology

200 papers

We consider $\kappa$-deformed relativistic quantum phase space and possible implementations of the Lorentz algebra. There are two ways of performing such implementations. One is a simple extension where the Poincar\'e algebra is unaltered,…

High Energy Physics - Theory · Physics 2019-06-26 D. Meljanac , S. Meljanac , S. Mignemi , R. Štrajn

A fully consistent linear perturbation theory for cosmology is derived in the presence of quantum corrections as they are suggested by properties of inverse volume operators in loop quantum gravity. The underlying constraints present a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald , Golam Mortuza Hossain , Mikhail Kagan , S. Shankaranarayanan

Braneworld scenarios are motivated by string/M-theory and can be characterized by the way in which they modify the conventional Friedmann equations of Einstein gravity. An alternative approach to quantum gravity, however, is the loop…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Edmund J. Copeland , James E. Lidsey , Shuntaro Mizuno

A non-singular bouncing cosmology is generically obtained in loop quantum cosmology due to non-perturbative quantum gravity effects. A similar picture can be achieved in standard general relativity in the presence of a scalar field with a…

General Relativity and Quantum Cosmology · Physics 2014-03-17 Yi-Fu Cai , Edward Wilson-Ewing

Two fundamental issues about the relation between the deformed Heisenberg-Weyl algebra in noncommutative space and the undeformed one in commutative space are elucidated. First the un-equivalency theorem between two algebras is proved: the…

High Energy Physics - Theory · Physics 2009-11-11 Jian-Zu Zhang

We propose new noncommutative models of quantum phase spaces, containing a pair of $\kappa$-deformed Poincar\'e algebras, with two independent double ($\kappa,\tilde{\kappa}$)-deformations in space-time and four-momenta sectors. The first…

High Energy Physics - Theory · Physics 2025-05-21 Jerzy Lukierski , Stjepan Meljanac , Salvatore Mignemi , Anna Pachoł , Mariusz Woronowicz

A general formalism is developed that allows the construction of field theory on quantum spaces which are deformations of ordinary spacetime. The symmetry group of spacetime is replaced by a quantum group. This formalism is demonstrated for…

High Energy Physics - Theory · Physics 2009-11-10 Marija Dimitrijevic , Larisa Jonke , Lutz Moeller , Efrossini Tsouchnika , Julius Wess , Michael Wohlgenannt

A model for a flat isotropic universe with a negative cosmological constant $\Lambda$ and a massless scalar field as sole matter content is studied within the framework of Loop Quantum Cosmology. By application of the methods introduced for…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Eloisa Bentivegna , Tomasz Pawlowski

The notion of $q$-grading on the enveloping algebra generated by products of q-deformed Heisenberg algebras is introduced for $q$ complex number in the unit disc. Within this formulation, we consider the extension of the notion of…

Mathematical Physics · Physics 2014-11-20 Joseph Ben Geloun , Mahouton Norbert Hounkonnou

Generators of the super-Poincar\'e algebra in the non-(anti)commutative superspace are represented using appropriate higher-derivative operators defined in this quantum superspace. Also discussed are the analogous representations of the…

High Energy Physics - Theory · Physics 2009-01-07 Rabin Banerjee , Choonkyu Lee , Sanjay Siwach

A geometric theory of brane-worlds with large or non-compact extra dimensions is presented. It is shown that coordinate gauge independent perturbations of the brane-world correspond to the Einstein-Hilbert dynamics derived from the…

High Energy Physics - Theory · Physics 2007-05-23 M. D. Maia , E. M. Monte

We study the representations of the three-dimensional Euclidean Snyder-de Sitter algebra. This algebra generates the symmetries of a model admitting two fundamental scales (Planck mass and cosmological constant) and is invariant under the…

High Energy Physics - Theory · Physics 2016-02-24 S. Mignemi , R. Strajn

An extensively tacit understandings of equivalency between the deformed Heisenberg-Weyl algebra in noncommutative space and the undeformed Heisenberg-Weyl algebra in commutative space is elucidated. Equivalency conditions between two…

Quantum Physics · Physics 2007-05-23 Jian-Zu Zhang

Spectrum and eigenfunctions in the momentum representation for 1D Coulomb potential with deformed Heisenberg algebra leading to minimal length are found exactly. It is shown that correction due to the deformation is proportional to square…

Quantum Physics · Physics 2009-11-11 T. V. Fityo , I. O. Vakarchuk , V. M. Tkachuk

We propose a new Doubly Special Relativity theory based on the generalization of the $\kappa$-deformation of the Poincar\'e algebra acting along one of the null directions. We recall the quantum Hopf structure of such deformed Poincar\'e…

High Energy Physics - Theory · Physics 2009-11-10 A. Blaut , M. Daszkiewicz , J. Kowalski-Glikman

A discussion is given of the quantisation of a physical system with finite degrees of freedom subject to a Hamiltonian constraint by treating time as a constrained classical variable interacting with an unconstrained quantum state. This…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Charles Wang

In this paper we study the quantisation of scalar field theory in $\kappa$-deformed space-time. Using a quantisation scheme that use only field equations, we derive the quantisation rules for deformed scalar theory, starting from the…

High Energy Physics - Theory · Physics 2019-09-23 E. Harikumar , Vishnu Rajagopal

A quantum Schwarzschild spacetime and a quantum Schwarzschild-de Sitter spacetime with cosmological constant $\Lambda$ are constructed within the framework of a noncommutative Riemannian geometry developed in an earlier publication. The…

High Energy Physics - Theory · Physics 2009-04-17 Ding Wang , R. B. Zhang , Xiao Zhang

We present a review on basic aspects of quantum cosmology in the presence of cut-off physics. We first analyze how the Wheeler-DeWitt equation in a pure metric approach describes the quantum Universe, showing how the singularity is not…

General Relativity and Quantum Cosmology · Physics 2021-09-20 Gabriele Barca , Eleonora Giovannetti , Giovanni Montani

The space-time symmetry of noncommutative quantum field theories with a deformed quantization is described by the twisted Poincar\'e algebra, while that of standard commutative quantum field theories is described by the Poincar\'e algebra.…

High Energy Physics - Theory · Physics 2008-11-26 Yasumi Abe