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We consider two model field theories on a noncommutative plane that have smooth commutative limits. One is the single-component fermion theory with quartic interaction that vanishes identically in the commutative limit. The other is a…

High Energy Physics - Theory · Physics 2009-10-31 Dongsu Bak , Sung Ku Kim , Kwang-Sup Soh , Jae Hyung Yee

We propose and construct a two-parameter perturbative expansion around a Friedmann-Lema\^{i}tre-Robertson-Walker geometry that can be used to model high-order gravitational effects in the presence of non-linear structure. This framework…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-15 Sophia R. Goldberg , Timothy Clifton , Karim A. Malik

We show that the principle of least action is generally inconsistent with the usual Kaluza-Klein program, the higher dimensional Einstein-Hilbert action being unbounded from below. This inconsistency is also present in other theories with…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. P. Mbelek , M. Lachieze-Rey

In this paper we study gauge-invariant metric fluctuations from a Noncompact Kaluza-Klein (NKK) theory of gravity in a de Sitter expansion. We recover the well known result $\delta\rho/\rho \simeq 2\Phi$, obtained from the standard 4D…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Jose Edgar Madriz Aguilar , Mariano Anabitarte , Mauricio Bellini

The equations describing the Kaluza-Klein reduction of conformally flat spaces are investigated in arbitrary dimensions. Special classes of solution related to pseudo-Kahler and para-Kahler structures are constructed and classified…

Mathematical Physics · Physics 2009-08-05 Paolo Maraner , Jiannis K. Pachos

We analyze the consistency of the ADM approach to KK model; we prove that KK reduction commute with ADM splitting. This leads to a well defined Hamiltonian; we provide the outcome. The electromagnetic constraint is derived from a…

General Relativity and Quantum Cosmology · Physics 2010-11-11 Valentino Lacquaniti , Giovanni Montani

We examine quantum corrections of time delay arising in the gravitational field of a spinning oblate source. Low-energy quantum effects occurring in Kerr geometry are derived within a framework where general relativity is fully seen as an…

Over the last few years, it was realised that non-canonical scalar fields can lead to the accelerated expansion in the early universe. The primordial spectrum in these scenarios not only shows near scale-invariance consistent with CMB…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-05 Corrado Appignani , Roberto Casadio , S. Shankaranarayanan

The ``Kaluza-Klein-type'' geometric structure appropriate to study the central extension of the Galilei group and non-relativistic physics is reviewed.

Mathematical Physics · Physics 2007-05-23 P. A. Horvathy

Quantum field theories (QFT's) on noncommutative spacetimes are currently under intensive study. Usually such theories have world sheet noncommutativity. In the present work, instead, we study QFT's with commutative world sheet and…

High Energy Physics - Theory · Physics 2008-11-26 A. P. Balachandran , A. R. Queiroz , A. M. Marques , P. Teotonio-Sobrinho

A new framework for noncommutative complex geometry on quantum homogeneous spaces is introduced. The main ingredients used are covariant differential calculi and Takeuchi's categorical equivalence for faithfully flat quantum homogeneous…

Quantum Algebra · Mathematics 2015-11-06 Réamonn Ó Buachalla

A double perturbation idea is presented in framework of the quark-gluon plasma kinetic theory. A solvable set of equations from the 'double perturbation' is derived and the equations are showed to be gauge-independent. The formalism of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xiaoping Zheng , Jiarong Li

We consider a condition for a charge confinement and gravito-electromagnetic wave solutions in the Nonsymmetric Kaluza-Klein Theory.We consider also an influence of a cosmological constant on a static,spherically symmetric solution.We…

High Energy Physics - Theory · Physics 2015-08-03 M. W. Kalinowski

The effects of compact extra dimensions upon quantum stress tensor fluctuations are discussed. It is argued that as the compactification volume decrease, these fluctuations increase in magnitude. In principle, this would have the potential…

General Relativity and Quantum Cosmology · Physics 2009-11-10 J. Borgman , L. H. Ford

We propose a mechanism to explain the fluctuations of the ground state energy in quantum dots in the Coulomb blockade regime. Employing the random matrix theory we show that shape deformations may change the adjacent peak spacing…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Raul O. Vallejos , Caio H. Lewenkopf , Eduardo R. Mucciolo

Using the language of differential forms, the Kaluza-Klein theory in 4+1 dimensions is derived. This theory unifies electromagnetic and gravitational interactions in four dimensions when the extra space dimension is compactified. Without…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ingunn Kathrine Wehus , Finn Ravndal

In this article we elaborate on a recently proposed interpretation of DSR as an effective measurement theory in the presence of non-negligible (albeit small) quantum gravitational fluctuations. We provide several heuristic arguments to…

General Relativity and Quantum Cosmology · Physics 2009-11-11 R. Aloisio , A. Galante , A. Grillo , S. Liberati , E. Luzio , F. Mendez

We study a stochastic formalism for a nonperturbative treatment of the inflaton field in the framework of a noncompact Kaluza-Klein (KK) theory during an inflationary (de Sitter) expansion, without the slow-roll approximation.

General Relativity and Quantum Cosmology · Physics 2008-11-26 Jose Edgar Madriz Aguilar , Mauricio Bellini

We discuss the non--linear growth of the kurtosis of the smoothed peculiar velocity field (along an arbitrary direction), in an Einstein--de Sitter universe, induced by Gaussian primordial density fluctuations. Applying the perturbative…

Astrophysics · Physics 2008-11-26 Paolo Catelan , Lauro Moscardini

In this note we present additional arguments in favour of Kaluza and Klein picture of the world. We show that geniusly simple formula provided by Kaluza-Klein approach gives an excellent description for the mass spectrum of two-nucleon…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. A. Arkhipov