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We consider the effective evolution of a phenomenological model from FLRW supersymmetric quantum cosmology with a scalar field. The scalar field acts as a clock and inflaton. We examine a family of simple superpotentials that produce an…

General Relativity and Quantum Cosmology · Physics 2022-08-17 N. E. Martínez-Pérez , C. Ramírez , V. M. Vázquez Báez

Usual inflation is realized with a slow rolling scalar field minimally coupled to gravity. In contrast, we consider dynamics of a scalar with a flat effective potential, conformally coupled to gravity. Surprisingly, it contains an attractor…

High Energy Physics - Theory · Physics 2008-11-26 Lev Kofman , Shinji Mukohyama

Models of cosmic inflation posit an early phase of accelerated expansion of the universe, driven by the dynamics of one or more scalar fields in curved spacetime. Though detailed assumptions about fields and couplings vary across models,…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-09 Alan H. Guth , David I. Kaiser , Yasunori Nomura

We present the first computation of the cosmological perturbations generated during inflation up to second order in deviations from the homogeneous background solution. Our results, which fully account for the inflaton self-interactions as…

Astrophysics · Physics 2010-04-05 V. Acquaviva , N. Bartolo , S. Matarrese , A. Riotto

In this work we use the Loop Quantum Cosmology modified scalar-tensor reconstruction techniques in order to investigate how bouncing and inflationary cosmologies can be realized. With regard to the inflationary cosmologies, we shall be…

General Relativity and Quantum Cosmology · Physics 2018-04-18 K. Kleidis , V. K. Oikonomou

Observational tests during the next decade may determine if the evolution of the Universe can be understood from fundamental physical principles, or if special initial conditions, coincidences, and new, untestable physical laws must be…

Astrophysics · Physics 2016-08-30 Paul J. Steinhardt

The standard model of cosmology assumes a homogeneous and isotropic universe that undergoes a period of exponential expansion very early on, named inflation. This stretches quantum fluctuations from the onset of inflation to cosmological…

General Relativity and Quantum Cosmology · Physics 2024-10-22 Rita B. Neves

Eternal inflation arising from a potential landscape predicts that our universe is one realization of many possible cosmological histories. One way to access different cosmological histories is via the nucleation of bubble universes from a…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-13 Matthew C. Johnson , Wei Lin

We show that inflationary cosmology may be used to test the statistical predictions of quantum theory at very short distances and at very early times. Hidden-variables theories, such as the pilot-wave theory of de Broglie and Bohm, allow…

High Energy Physics - Theory · Physics 2014-11-18 Antony Valentini

Since inflationary perturbations must generically couple to all degrees of freedom present in the early Universe, it is more realistic to view these fluctuations as an open quantum system interacting with an environment. Then, on very…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-10 Jerome Martin , Vincent Vennin

This thesis investigates cosmological particle production within Quantum Field Theory in Curved Spacetimes, both as a dark matter mechanism and through analog simulations using Bose-Einstein condensates. While a full theory of Quantum…

General Relativity and Quantum Cosmology · Physics 2026-02-12 Álvaro Parra-López

The Wheeler--DeWitt equation for a flat and compact Friedmann--Lema\^{i}tre--Robertson--Walker cosmology at the pre-inflation epoch is studied in the contexts of the standard and fractional quantum cosmology. Working within the…

General Relativity and Quantum Cosmology · Physics 2023-04-17 S. M. M. Rasouli , E. W. Oliveira Costa , P. V. Moniz , S. Jalalzadeh

We study the evolution of quantum fluctuations of gravity around an inflationary solution in renormalizable quantum gravity, in which the initial scalar-fluctuation dominance is shown by the background-free nature expressed by a special…

High Energy Physics - Theory · Physics 2024-01-19 Ken-ji Hamada

We study the effect of quantum decoherence on the inflationary cosmological perturbations. This process might imprint specific observational signatures revealing the quantum nature of the inflationary mechanism being related to the…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-03 Aoumeur Daddi Hammou , Nicola Bartolo

We explore the possibility of describing our universe with a singularity--free, closed, spatially homogeneous and isotropic cosmological model, using only general relativity and a suitable equation of state which produces an inflationary…

Astrophysics · Physics 2010-11-01 S. S. Bayin , F. I. Cooperstock , V. Faraoni

The aim of this paper is to provide a more precise description of the paradigm of corpuscular slow-roll inflation, which was previously introduced by Casadio et al. in [1]. Specifically, we start by expanding the Starobinsky theory on a…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Andrea Giugno , Andrea Giusti

We clarify the way in which cosmological perturbations of quantum origin, produced during inflation, assume classical properties. Two features play an important role in this process: First, the dynamics of fluctuations which are presently…

General Relativity and Quantum Cosmology · Physics 2016-10-26 C. Kiefer , D. Polarski

We show how the quantum-to-classical transition of the cosmological fluctuations produced during an inflationary stage can be described using the consistent histories approach. We identify the corresponding histories in the limit of…

General Relativity and Quantum Cosmology · Physics 2009-05-20 David Polarski

We discuss a new scenario for early cosmology, when inflationary de Sitter phase dynamically emergent. This genuine quantum effect occurs as a result of dynamics of the topologically nontrivial sectors in a (conjectured) strongly coupled…

High Energy Physics - Phenomenology · Physics 2014-08-13 Ariel R. Zhitnitsky

Observations of the cosmic microwave sky are revealing the primordial non-uniformities from which all structure in the Universe grew. The only known physical mechanism for generating the inhomogeneities we see involves the amplification of…

Astrophysics · Physics 2009-10-31 Neil Turok