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Related papers: Uncosmology

200 papers

We argue that standard tools of holography can be used to describe fully non-perturbative microscopic models of cosmology in which a period of accelerated expansion may result from the positive potential energy of time-dependent scalar…

High Energy Physics - Theory · Physics 2022-03-23 Stefano Antonini , Petar Simidzija , Brian Swingle , Mark Van Raamsdonk

We consider cosmological consequences of a conformal invariant formulation of Einstein's General Relativity where instead of the scale factor of the spatial metrics in the action functional a massless scalar (dilaton) field occurs which…

General Relativity and Quantum Cosmology · Physics 2011-07-19 D. Behnke , D. Blaschke , V. N. Pervushin , D. Proskurin

Quantum cosmology in the presence of a fundamental minimal length is analyzed in the context of the flat isotropic and the Taub cosmological models. Such minimal scale comes out from a generalized uncertainty principle and the quantization…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Marco Valerio Battisti , Giovanni Montani

We show that the noncommutative Wess-Zumino model is renormalizable to all orders of perturbation theory. The noncommutative scalar potential by itself is non-renormalizable but the Yukawa terms demanded by supersymmetry improve the…

High Energy Physics - Theory · Physics 2009-10-31 H. O. Girotti , M. Gomes , V. O. Rivelles , A. J. da Silva

We study a possibility of anisotropic scale invariant cosmology. It is shown that within the conventional Einstein gravity, the violation of the null energy condition is necessary. We construct an example based on a ghost condensation model…

High Energy Physics - Theory · Physics 2011-03-04 Yu Nakayama

In this paper we place new constraints on a f(R) modified gravity model recently proposed by Hu and Sawicki. After checking that the Hu and Sawicki model produces a viable cosmology, i.e. a matter dominated epoch followed by a late-time…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-09 Matteo Martinelli , Alessandro Melchiorri , Luca Amendola

In this talk we would like to review recent results on non-singular cosmological models. It has been recently shown that among stiff perfect fluid inhomogeneous spacetimes the absence of singularities is more common than it was expected in…

General Relativity and Quantum Cosmology · Physics 2009-04-29 L. Fernández-Jambrina , L. M. González-Romero

A quantum theory of asymptotically flat space-times is presented using the solutions of the Null Surface Formulation (NSF) field equations in a perturbative scheme. Free-field commutation relations are given for the null free data of NSF at…

High Energy Physics - Theory · Physics 2025-06-30 Carlos N. Kozameh , Lautaro Zapata-Altuna

In this paper, we present the cosmological perturbation formalism for theories within the framework of affine gravity. These theories are distinguished by their connection, devoid of any metric. Our approach involves segregating…

General Relativity and Quantum Cosmology · Physics 2024-01-17 Oscar Castillo-Felisola , Radouane Gannouji , Manuel Morocho-López , Marcelo Rozas-Rojas

Primordial nucleosynthesis is considered a success story of the standard big bang (SBB) cosmology. The cosmological and elementary particle physics parameters are believed to be severely constrained by the requirement of correct abundances…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Daksh Lohiya , Annu Batra , Shobhit Mahajan , Amitabha Mukherjee

We explore phenomenological consequences of coupling a non-conformal scale-invariant theory to the standard model. We point out that, under certain circumstances, non-conformal scale-invariant theories have oscillating correlation functions…

High Energy Physics - Theory · Physics 2012-03-07 Jean-François Fortin , Benjamin Grinstein , Andreas Stergiou

It is known that some cosmological perturbations are conformal invariant. This facilitates the studies of perturbations within some gravitational theories alternative to general relativity, for example the scalar-tensor theory, because it…

General Relativity and Quantum Cosmology · Physics 2015-10-21 Mingzhe Li , Yicen Mou

The cosmological constant problem represents a profound conflict between quantum field theory and general relativity. Unimodular gravity offers a compelling starting point by de-gravitating the vacuum energy of the Standard Model, but this…

High Energy Physics - Phenomenology · Physics 2025-11-18 David E. Kaplan , Surjeet Rajendran

We provide a realisation of a singularity-free inflationary universe in the form of a simple cosmological model dominated at early times by a single minimally coupled scalar field with a physically based potential. The universe starts…

General Relativity and Quantum Cosmology · Physics 2008-11-26 George F. R. Ellis , Jeff Murugan , Christos G. Tsagas

We study curved isotropic cosmologies filled with two interacting fluids near their time singularities. We find that a number of these universes asymptote to flat limits in the sense that their asymptotic properties become indistinguishable…

General Relativity and Quantum Cosmology · Physics 2013-10-30 Spiros Cotsakis , Georgia Kittou

The problem of the physical nature and the cosmological constant genesis is discussed. This problem can't be solved in terms of the current quantum field theory which operates with Higgs and nonperturbative vacuum condensates and takes into…

Astrophysics · Physics 2007-05-23 Vladimir Burdyuzha , Olga Lalakulich , Yuri Ponomarev , Grigory Vereshkov

By means of a combined use of the type Ia supernovae and H(z) data tests, together with the study of the asymptotic properties in the equivalent phase space - through the use of the dynamical systems tools - we demonstrate that the bulk…

General Relativity and Quantum Cosmology · Physics 2013-08-30 Arturo Avelino , Ricardo Garcia-Salcedo , Tame Gonzalez , Ulises Nucamendi , Israel Quiros

A closed mathematical model of the statistical self-gravitating system of scalar charged particles for conformal invariant scalar interactions is constructed on the basis of relativistic kinetics and gravitation theory. Asymptotic…

General Relativity and Quantum Cosmology · Physics 2015-08-13 Yurii Ignat'ev

Non-Hermiticity gives rise to unique topological phases without Hermitian analogs. However, the effective field theory has yet to be established. Here, we develop a field-theoretical description of the intrinsic non-Hermitian topological…

Mesoscale and Nanoscale Physics · Physics 2021-06-01 Kohei Kawabata , Ken Shiozaki , Shinsei Ryu

Some remarkable examples of alternative cosmological theories are reviewed here, ranging from a compilation of variations on the Standard Model through the more distant quasi-steady-state cosmology, plasma cosmology, or universe models as a…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-17 Martin Lopez-Corredoira , Louis Marmet