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Related papers: Rolling Tachyon in Nonlocal Cosmology

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We propose a nonlocal scalar-tensor model of gravity with pseudodifferential operators inspired by the effective action of p-adic string and string field theory on flat spacetime. An infinite number of derivatives act both on the metric and…

High Energy Physics - Theory · Physics 2010-12-28 Gianluca Calcagni , Giuseppe Nardelli

The resolution of the problem of cosmological singularity in the framework of gauge theories of gravitation is discussed. Generalized cosmological Friedmann equations for homogeneous isotropic models filled by interacting scalar fields and…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Albert V. Minkevich

The classical trajectories for FLRW universe with varying speed of light are obtained for the cases in which the cosmological constant depends or not depend on the velocity of light. The theory is then quantized and the corresponding WDW…

General Relativity and Quantum Cosmology · Physics 2010-01-25 F. Shojai , S. Molladavoudi

Several extensions of General Relativity and high energy physics include scalar fields as extra degrees of freedom. In the search for predictions in the non-linear regime of cosmological evolution, the community makes use of numerical…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-04 Claudio Llinares , David Mota

A nonlinear Wightman field is taken to be a nonlinear map from a linear space of test functions to a linear space of Hilbert space operators, with inessential modifications to other axioms only to the extent dictated by the introduction of…

Mathematical Physics · Physics 2012-12-07 Peter Morgan

Double field theory (DFT) offers a manifest T-duality formulation for massless closed string field theory with both momentum and winding excitation. The gauge symmetry is defined by the generalized Lie derivative which is the extension of…

High Energy Physics - Theory · Physics 2015-06-19 Chen-Te Ma , Che-Min Shen

Brane cosmologies with static, five-dimensional and Z_2 symmetric bulks are analysed. A general solution generating mechanism is outlined. The qualatitive cosmological behaviour of all such solutions is determined. Conditions for avoiding…

High Energy Physics - Phenomenology · Physics 2009-11-07 Stephen C. Davis

In this first article of a series on alternative cosmological models we present an extended version of a cosmological model in Weyl-Cartan spacetime. The new model can be viewed as a generalization of a model developed earlier jointly with…

General Relativity and Quantum Cosmology · Physics 2009-04-03 Dirk Puetzfeld

We present a suite of cosmological N-body simulations describing the "Running Friedmann-Lema{\"i}tre-Robertson-Walker" (R-FLRW) cosmological model. This model is based on quantum field theory in a curved space-time and extends {\Lambda}CDM…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-25 Antonio Bibiano , Darren J. Croton

We consider the formulation of two dimensional QCD in terms of gauge invariant bilocal operators (string field) which satisfy a $W_\infty$ algebra. In analogy with our work on the $c=1$ string field theory we derive an action and associated…

High Energy Physics - Theory · Physics 2009-10-28 Avinash Dhar , Gautam Mandal , Spenta R. Wadia

We herein set forth intrinsically four-dimensional string solutions and analyze some of its properties. The solutions are constructed as gauged WZW models of the coset $SO(2,2)/SO(2)\times SO(1,1)$. We recover backgrounds having metric and…

High Energy Physics - Theory · Physics 2009-10-30 Leopoldo A. Pando Zayas

Space-time non-commutative theories are non-local in time. We develop the Hamiltonian formalism for non-local field theories in d space-time dimensions by considering auxiliary d+1 dimensional field theories which are local with respect to…

High Energy Physics - Theory · Physics 2008-11-26 Joaquim Gomis , Kiyoshi Kamimura , Josep Llosa

We discuss the formulation of cosmological topologically massive (simple) supergravity theory in three-dimensional Riemann-Cartan space-times. We use the language of exterior differential forms and the properties of Majorana spinors on…

General Relativity and Quantum Cosmology · Physics 2021-07-07 Tekin Dereli , Cem Yetişmişoğlu

Some aspects of two General Relativistic cosmological solutions, an exact $\Lambda$CDM-like cosmological solution $j=1$ ($j$ is cosmographic jerk parameter), and a specifically designed toy cosmological solution $j=1+3\varepsilon(q-1/2)$…

General Relativity and Quantum Cosmology · Physics 2026-02-09 Saikat Chakraborty , Piyabut Burikham

We discuss a new formula for the symplectic structure on the phase space of open string field theory. Revisiting the setup of Cho, Mazel, and Yin, we use the formula to compute the energy of rolling tachyon solutions on unstable D-branes.…

High Energy Physics - Theory · Physics 2026-02-10 Vinícius Bernardes , Theodore Erler , Atakan Hilmi Fırat

We study the cosmological implications of the one-loop terms in the string expansion. In particular, we find non-singular solutions which interpolate between a contracting universe and an expanding universe, and show that these solutions…

High Energy Physics - Theory · Physics 2009-10-30 Richard Easther , Kei-ichi Maeda

The semi classical cosmology approximation for a Friedman Robertson Walker geometry coupled to a field is considered. A power series of the field with coefficients that depend on the radius of the geometry is proposed, and the equations for…

General Relativity and Quantum Cosmology · Physics 2011-04-12 Jose L. Martinez-Morales

In this work a supersymmetric cosmological model is analyzed in which we consider a general superfield action of a homogeneous scalar field supermultiplet interacting with the scale factor in a supersymmetric FRW model. There appear…

General Relativity and Quantum Cosmology · Physics 2010-12-15 Celia Escamilla-Rivera , Octavio Obregon , L. Arturo Urena-Lopez

It is well known that string theories naturally compactify on anti-de Sitter spaces, and yet cosmological observations show no evidence of a negative cosmological constant in the early Universe's evolution. In this letter we present two…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-03 Tomislav Prokopec

We construct integrable chiral cosmological models with two scalar fields and potentials represented in terms of hyperbolic functions. Using the conformal transformation of the metric and the corresponding models with induced gravity terms,…

General Relativity and Quantum Cosmology · Physics 2024-11-18 Vsevolod R. Ivanov , Sergey Yu. Vernov
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