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Related papers: Effective equations in quantum cosmology

200 papers

We consider a physically viable cosmological model that has a field dependent Gauss-Bonnet coupling in its effective action, in addition to a standard scalar field potential. The presence of such terms in the four dimensional effective…

High Energy Physics - Theory · Physics 2008-11-26 Ishwaree P Neupane , Benedict M N Carter

We develop a method to calculate generic time-dependent correlation functions for inhomogeneous quantum quenches in (1+1)-dimensional conformal field theory (CFT) induced by sudden Hamiltonian deformations that modulate the energy density…

Statistical Mechanics · Physics 2025-06-06 Xinyu Liu , Alexander McDonald , Tokiro Numasawa , Biao Lian , Shinsei Ryu

We incorporate the concept of dimensional reduction at high energies within the perturbative formulation of quantum field theory. In this new framework, space and momentum integrations are modified by a weighting function incorporating an…

High Energy Physics - Theory · Physics 2023-04-19 Alessio Maiezza , Juan Carlos Vasquez

An effective quantum field theory (QFT) with a manifest UV/IR connection, so as to be valid for arbitrarily large volumes, can successfully be applied to the cosmological dark energy problem as well as the cosmological constant (CC)…

General Relativity and Quantum Cosmology · Physics 2009-11-19 R. Horvat

An algorithm is used to generate new solutions of the scalar field equations in homogeneous and isotropic universes. Solutions can be found for pure scalar fields with various potentials in the absence and presence of spatial curvature and…

General Relativity and Quantum Cosmology · Physics 2016-11-23 John D. Barrow , Andronikos Paliathanasis

The anomaly-induced effective action is a useful tool for deriving the contributions coming from quantum effects of massless conformal fields. It is well-known that such corrections in the higher derivative vacuum sector of the…

High Energy Physics - Theory · Physics 2011-06-27 Ana M. Pelinson , Ilya L. Shapiro

We study solutions of the Wheeler-DeWitt equation corresponding to an S-modular invariant N=1 supergravity model and a closed homogeneous and isotropic Friedmann-Robertson-Walker spacetime. The issues of inflation and of the cosmological…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Orfeu Bertolami , Ricardo Schiappa

We study the quantum dynamics of a single mode/particle interacting inhomogeneously with a large number of particles and introduce an effective approach to find the accessible Hilbert space where the dynamics takes place. Two relevant…

Quantum Physics · Physics 2015-06-26 C. E. Lopez , H. Christ , J. C. Retamal , E. Solano

We discuss the computation of the quantum effective action of strongly interacting field theories using holographic duality, and its use to determine quasi-equilibrium parameters of first order phase transitions relevant for gravitational…

High Energy Physics - Theory · Physics 2022-03-31 Fëanor Reuben Ares , Oscar Henriksson , Mark Hindmarsh , Carlos Hoyos , Niko Jokela

In this contribution we summarize two recent applications of a correspondence between backreaction terms in averaged inhomogeneous cosmologies and an effective scalar field (the `morphon'). Backreaction terms that add to the standard…

General Relativity and Quantum Cosmology · Physics 2010-12-15 Thomas Buchert , Nathaniel Obadia , Xavier Roy

The cosmological constant problem can be understood as the failure of the decoupling principle behind effective field theory, so that some quantities in the low-energy theory are extremely sensitive to the high-energy properties. While this…

High Energy Physics - Theory · Physics 2015-12-01 Carlos Barceló , Raúl Carballo-Rubio , Luis J. Garay

Multidimensional cosmological models with $n~(n > 1)$ Einstein spaces are discussed classically and with respect to canonical quantization. These models are integrable in the case of Ricci flat internal spaces. For negative curvature of the…

General Relativity and Quantum Cosmology · Physics 2009-09-25 U. Bleyer , A. Zhuk

Combining the equivalence between cosmological particle creation and an effective viscous fluid pressure with the fact that the latter represents a dynamical degree of freedom within the second-order Israel-Stewart theory for imperfect…

Astrophysics · Physics 2009-10-31 Winfried Zimdahl

The Einstein-Klein-Gordon field equations are solved in a inhomogeneous shear-free universe containing a material fluid, a self-interacting scalar field, a variable cosmological term, and a heat flux. A quintessence-dominated scenario…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Luis P. Chimento , Alejandro S. Jakubi , Diego Pavon

We analyze cosmological perturbations to the linear order in the context of inflation with an arbitrary number of scalar fields. The fields take values on a non-trivial manifold with a positive-definite metric and are non-minimally coupled…

Astrophysics · Physics 2007-05-23 Joydev Lahiri , Gautam Bhattacharya

We consider the Abelian model of a complex scalar field coupled to a gauge field within the framework of General Relativity and search for cosmological solutions. For this purpose we assume a homogeneous, isotropic and uncharged Universe…

Astrophysics · Physics 2009-11-10 Daniele S. M. Alves , Gilberto M. Kremer

The nonequilibrium dynamics of quantum fields is studied in inflationary cosmology, with particular emphasis on applications to the problem of post-inflation reheating. The Schwinger-Keldysh closed-time-path (CTP) formalism is utilized…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Stephen A. Ramsey

This article lays out a complete framework for an effective theory of cosmological perturbations with corrections from canonical quantum gravity. Since several examples exist for quantum-gravity effects that change the structure of…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Aurelien Barrau , Martin Bojowald , Gianluca Calcagni , Julien Grain , Mikhail Kagan

We present a modular cosmology scenario where the difficulties encountered in conventional modular cosmology are solved in a self-consistent manner, with definite predictions to be tested by observation. Notably, the difficulty of the…

High Energy Physics - Phenomenology · Physics 2009-11-10 Kenji Kadota , Ewan D. Stewart

Holographic considerations may provide a glimpse of quantum gravity beyond what is currently accessible by other means. Here we apply holography to inflationary cosmology. We argue that the appropriate holographic bound on the total entropy…

High Energy Physics - Theory · Physics 2007-05-23 Andreas Albrecht , Nemanja Kaloper , Yong-Seon Song