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Related papers: Cosmology as a Crossed Product

200 papers

In the context of loop quantum cosmology, we consider an inflationary era driven by a canonical scalar field and occurring in the semiclassical regime, where spacetime is a continuum but quantum gravitational effects are important. The…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Gianluca Calcagni , Marina Cortes

We describe inflation in terms of a time dependent quantum density matrix with time playing the role of a stochastic variable. Using a quasi-de Sitter model we compute the corresponding quantum Fisher information function as the second…

High Energy Physics - Theory · Physics 2020-09-16 Cesar Gomez , Raul Jimenez

This thesis is centered on three main subjects within the theory of inflation and cosmological perturbations: loop corrections to the power spectrum of curvature fluctuations generated during inflation; evolution of cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-13 Emanuela Dimastrogiovanni

The space of inflationary models is vast, containing wide varieties of mechanisms, symmetries, and spectra of particles. Consequently, the space of observational signatures is similarly complex. Hence, it is natural to look for boundaries…

High Energy Physics - Theory · Physics 2020-10-29 Daniel Green , Enrico Pajer

Inflationary cosmology attempts to provide a natural explanation for the flatness and homogeneity of the observable universe. In the context of reversible (unitary) evolution, this goal is difficult to satisfy, as Liouville's theorem…

High Energy Physics - Theory · Physics 2010-07-09 Sean M. Carroll , Heywood Tam

In this work we investigate the behavior of three-dimensional (3D) cosmological models. The simulation of inflationary and dark-energy-dominated eras are among the possible results in these 3D formulations; taking as starting point the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 M. H. Christmann , F. P. Devecchi , G. M. Kremer , C. M. Zanetti

Infinite entanglement fluctuations appear when a quantum field theory on a causally complete domain of space-time is a type $III$ factor. In the weak gravity limit $G_N=0$ this factor can be transformed into a crossed product type $II$…

High Energy Physics - Theory · Physics 2023-03-01 C. Gomez

We consider cosmological inflation generated by a scalar field slowly rolling off from a de Sitter maximum of its potential. The models belong to the class of hilltop models and represent the most general model of this kind in which the…

General Relativity and Quantum Cosmology · Physics 2016-09-05 Mariano Cadoni , Edgardo Franzin , Salvatore Mignemi

In the standard inflationary paradigm the inhomogeneities observed in the CMB arise from quantum fluctuations of an initially homogeneous and isotropic vacuum state. This picture suffers from two well-known weaknesses. First, it assumes…

General Relativity and Quantum Cosmology · Physics 2026-01-21 Gabriel R. Bengochea , Gabriel Leon , Alejandro Perez

We revisit pure quantum cosmology in three dimensions. The Wheeler-DeWitt equation can be solved perturbatively and the dynamics reduces to a particle on moduli space. Its time evolution is equivalent to the $T\overline{T}$ deformation.…

High Energy Physics - Theory · Physics 2024-05-21 Victor Godet

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

Inflationary scenarios motivated by high-energy physics generically contain a plethora of degrees of freedom beyond the primordial curvature perturbation. The latter interacts in a simple way with what we name "inflationary flavor…

High Energy Physics - Theory · Physics 2023-01-23 Lucas Pinol , Shuntaro Aoki , Sébastien Renaux-Petel , Masahide Yamaguchi

We calculate the power spectrum of vacuum fluctuations of a generic scalar field in a quantum cosmological setting that is manifestly singularity-free. The power spectrum is given in terms of the usual scale invariant spectrum plus scale…

Astrophysics · Physics 2007-05-23 S. Hofmann , O. Winkler

This pedagogical review aims at presenting the fundamental aspects of the theory of inflationary cosmological perturbations of quantum-mechanical origin. The analogy with the well-known Schwinger effect is discussed in detail and a…

High Energy Physics - Theory · Physics 2008-11-26 Jerome Martin

We wish to demonstrate how the presence of a dynamic cosmological parameter, plus a model of the universe as a quantum computer can be combined to give us a picture of early universe inflationary physics which is quite non linear, with a…

Mathematical Physics · Physics 2011-11-10 A. W. Beckwith

We introduce a fully-frame covariant formalism for inflation by taking into account conformal transformations in addition to field reparametrizations. We begin by providing a brief overview of frame problems in the history of science before…

High Energy Physics - Theory · Physics 2018-01-23 Sotirios Karamitsos , Apostolos Pilaftsis

The next decade will feature an abundance of novel cosmological data, while many fundamental questions about inflation remain. Given this, there is ample need for maximally efficient calculations, especially in non-standard scenarios for…

General Relativity and Quantum Cosmology · Physics 2023-05-10 Panagiotis Christeas , Logan Thomas

In this article we review the theory of cosmological inflation with a particular focus on the beautiful connection it provides between the physics of the very small and observations of the very large. We explain how quantum mechanical…

Astrophysics · Physics 2010-04-30 Daniel Baumann , Hiranya V. Peiris

Inflation, a period of exponential expansion in the early Universe, is considered an important part of the standard $\Lambda$CDM cosmological model, and plays a crucial role in explaining a wide range of current observations. The standard…

General Relativity and Quantum Cosmology · Physics 2023-12-08 Maria Pia Piccirilli , Gabriel Leon

We introduce a frame-covariant formalism for inflation of scalar-curvature theories by adopting a differential geometric approach which treats the scalar fields as coordinates living on a field-space manifold. This ensures that our…

High Energy Physics - Phenomenology · Physics 2018-01-09 Sotirios Karamitsos , Apostolos Pilaftsis