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Related papers: Primary Inflation

200 papers

We discuss early cosmology in theories where the fundamental Planck mass is close to the TeV scale. In such theories the standard model fields are localized to a (3+1)-dimensional wall with n new transverse sub-millimeter sized spatial…

High Energy Physics - Phenomenology · Physics 2009-10-31 Nima Arkani-Hamed , Savas Dimopoulos , Nemanja Kaloper , John March-Russell

We show how a radiation dominated universe subject to space-time quantization may give rise to inflation as the radiation temperature exceeds the Planck temperature. We consider dispersion relations with a maximal momentum (i.e. a mimimum…

High Energy Physics - Theory · Physics 2009-11-07 Stephon Alexander , Robert Brandenberger , Joao Magueijo

A novel scalar field free approach to cosmic inflation is presented. The inflationary Universe and the radiation dominated Universe are shown, within the framework of unified brane cosmology, to be two different phases governed by one and…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Aharon Davidson , Ilya Gurwich

We review conceptual aspects of inflationary scenarios able to produce primordial black holes, by amplifying the size of curvature fluctuations to the level required for triggering black hole formation. We identify general mechanisms to do…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-10 Ogan Özsoy , Gianmassimo Tasinato

The inflationary scenario for the brane world driven by the bulk inflaton is proposed. The quantum fluctuations of the inflaton is calculated and compared to those of the conventional 4-dimensional inflationary scenario. It is shown that…

High Energy Physics - Theory · Physics 2009-10-31 Shinpei Kobayashi , Kazuya Koyama , Jiro Soda

We investigate the initiation of cosmic inflation, in full numerical relativity, from pre-inflationary scenarios with large tensor and vector fluctuations in the metric. These settings are characterized by having large values in the Weyl…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-04 Cristian Joana

The basic workings of inflationary models are summarized, along with the arguments that strongly suggest that our universe is the product of inflation. I describe the quantum origin of density perturbations, giving a heuristic derivation of…

Astrophysics · Physics 2007-05-23 Alan H. Guth

This article discusses density perturbations in inflationary models, offering a pedagogical description of how these perturbations are generated by quantum fluctuations in the early universe. A key feature of inflation is that that rapid…

High Energy Physics - Theory · Physics 2014-01-15 Alan H. Guth

I study a model which describes the birth of the universe using a global topological phase transition with a complex manifold where the time, $\tau$, is considered as a complex variable. Before the big bang $\tau$ is a purely imaginary…

General Relativity and Quantum Cosmology · Physics 2017-05-24 Mauricio Bellini

We discuss how initial conditions for cosmological evolution can be defined in Loop Quantum Cosmology with massive scalar field and how the presence of the bounce influences the probability of inflation in this theory, compared with General…

General Relativity and Quantum Cosmology · Physics 2019-02-15 Suzana Bedić , Gregory Vereshchagin

Motivated by brane cosmology we solve the Einstein equations with a time dependent cosmological constant. Assuming that at an early epoch the vacuum energy scales as $1/logt $, we show that the universe passes from a fast growing phase…

General Relativity and Quantum Cosmology · Physics 2014-11-17 E. Papantonopoulos , I. Pappa

We study initial conditions for inflation in scenarios where the inflaton potential has a plateau shape. Such models are those most favored by Planck data and can be obtained in a large number of model classes. As a representative example,…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-29 Tommi Tenkanen , Eemeli Tomberg

I present a brief review of astro-ph/0406099, which argues that there is a limit on the number of efolds of inflation which are observable in a universe which undergoes an eternally accelerated expansion in the future. Such an acceleration…

High Energy Physics - Theory · Physics 2007-05-23 Matthew Kleban

We propose a method to extract predictions from quantum cosmology for inflation that can be confronted with observations. Employing the tunneling boundary condition in quantum geometrodynamics, we derive a probability distribution for the…

General Relativity and Quantum Cosmology · Physics 2015-07-21 Gianluca Calcagni , Claus Kiefer , Christian F. Steinwachs

We consider the brane gas picture of the early universe. At later stages, when there are no winding modes and the background is free to expand, we show that a moving 3-brane, which we identify with our universe, can inflate even though it…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. F. Parry , D. A. Steer

We consider the description of cosmological dynamics from the onset of inflation by a perfect fluid whose parameters must be consistent with the strength of the enhanced quantum loop effects that can arise during inflation. The source of…

General Relativity and Quantum Cosmology · Physics 2010-04-14 N. C. Tsamis , R. P. Woodard

It has recently been suggested that Planck scale physics may effect the evolution of cosmological fluctuations in the early stages of cosmological inflation in a non-trivial way, leading to an excited state for modes whose wavelength is…

High Energy Physics - Theory · Physics 2009-11-10 Robert H. Brandenberger , Jerome Martin

A scenario with two subsequent periods of inflationary expansion in the very early universe is examined. The model is based on a potential motivated by symmetries being found in field theory at high energy. For various parameter sets of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 Simon Schettler , Jurgen Schaffner-Bielich

It is commonly believed that our Universe has experienced two different stages of accelerated expansion. The early stage is known as inflation and the current acceleration is driven by dark energy. Observing inflation and dark energy…

Astrophysics · Physics 2009-11-11 Jun-Qing Xia , Gong-Bo Zhao , Bo Feng , Xinmin Zhang

Cosmological models with inflation and those with bounce have their own strengths and weaknesses. Here we construct a model in which a phase of bounce is followed by a viable inflationary phase. This incorporates several advantages of both…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-02 Manjeet Kaur , Debottam Nandi , Debajyoti Choudhury , T. R. Seshadri