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Related papers: Comment on Inflation and Alternative Cosmology

200 papers

We compare two holographic arguments that impose especially strong bounds on the amount of inflation. One comes from the de Sitter Equilibrium cosmology and the other from the work of Banks and Fischler. We find that simple versions of…

General Relativity and Quantum Cosmology · Physics 2015-03-05 Daniel Phillips , Andrew Scacco , Andreas Albrecht

I review two cosmological paradigms which are alternative to the current inflationary scenario. The first alternative is the "matter bounce", a non-singular bouncing cosmology with a matter-dominated phase of contraction. The second is an…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Robert H. Brandenberger

These notes present a brief introduction to Hot Big Bang cosmology and Cosmic Inflation, together with a selection of some recent attempts to embed inflation into string theory. They provide a partial description of lectures presented in…

High Energy Physics - Theory · Physics 2011-02-09 C. P. Burgess

On the one hand, inflation is an extremely convincing scenario: it solves most cosmological paradoxes and generates fluctuations that became the seeds for the growth of structures. It, however, suffers from a "naturalness" problem:…

General Relativity and Quantum Cosmology · Physics 2011-08-04 Aurelien Barrau

The basic workings of inflationary models are summarized, along with the arguments that strongly suggest that our universe is the product of inflation. The mechanisms that lead to eternal inflation in both new and chaotic models are…

Astrophysics · Physics 2009-10-31 Alan H. Guth

Fundamental theories of quantum gravity such as supergravity include a four form field strength which contributes to the cosmological constant. The inclusion of such a field into our theory of open inflation (hep-th/9802030) allows an…

High Energy Physics - Theory · Physics 2009-10-31 Neil Turok , S. W. Hawking

Anthropic principle can help us to understand many properties of our world. However, for a long time this principle seemed too metaphysical and many scientists were ashamed to use it in their research. I describe here a justification of the…

High Energy Physics - Theory · Physics 2007-05-23 Andrei Linde

Recent progress in the preheating phenomena for inflationary cosmology is reviewed. We first discuss estimates of the preheating time scale and particle production at the early stages of parametric amplification within the Mathieu and Lam'e…

Astrophysics · Physics 2008-02-03 D. Boyanovsky , H. J. de Vega , R. Holman , J. F. J. Salgado

The early stages of the universe evolution are discussed according to the hot big bang model and the grand unified theories. The shortcomings of big bang are summarized and their resolution by inflationary cosmology is sketched.…

High Energy Physics - Phenomenology · Physics 2008-11-26 George Lazarides

Cosmic Inflation provides an attractive framework for understanding the early universe and the cosmic microwave background. It can readily involve energies close to the scale at which Quantum Gravity effects become important. General…

High Energy Physics - Theory · Physics 2015-04-22 Anton de la Fuente , Prashant Saraswat , Raman Sundrum

Inflationary models of the early universe provide a natural mechanism for the formation of large scale structure. This success brings to forefront the question of naturalness: Does a sufficiently long slow roll inflation occur generically…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Abhay Ashtekar , David Sloan

Power spectra always play an important role in the theory of inflation. In particular, the ability to reproduce the galaxy matter power spectrum and the CMB temperature angular power spectrum coefficients to high accuracy is often…

General Relativity and Quantum Cosmology · Physics 2019-11-01 Herbert W. Hamber , Lu Heng Sunny Yu

In the first part of this paper, we outline the construction of an inflationary cosmology in the framework where inflation is described by a universally evolving scalar field, with the Lagrangian ${\cal L}_\phi=-{1/2}(\partial\phi)^2…

Astrophysics · Physics 2009-12-15 Ishwaree P. Neupane , Christoph Scherer

We consider the inflation produced by two coupled fluids in the flat Friedmann-Robertson-Walker universe. Different cosmological models for describing inflation by use of an inhomogeneous equation of state for the fluid are investigated.…

General Relativity and Quantum Cosmology · Physics 2016-05-12 I. Brevik , A. V. Timoshkin

Alexei Starobinsky is one of the main authors of inflationary cosmology. Here I will discuss the Starobinsky model and its generalizations, including the theory of $\alpha$-attractors. I will then describe the current status of these models…

High Energy Physics - Theory · Physics 2025-11-14 Andrei Linde

We present a simplified review of inflationary cosmology across various modified gravity theories. These include models based on curvature, torsion, and non-metricity. We explore how scalar fields interact with different geometric…

General Relativity and Quantum Cosmology · Physics 2025-12-16 Davood Momeni

Classic inflation, the theory described in textbooks, is based on the idea that, beginning from typical initial conditions and assuming a simple inflaton potential with a minimum of fine-tuning, inflation can create exponentially large…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-18 Anna Ijjas , Paul J. Steinhardt , Abraham Loeb

Reply to the comment by L. Kofman, A. Linde and A.A. Starobinsky (hep-ph/9608341) to our article ``Analytic and Numerical Study of Preheating Dynamics'' (hep-ph/9608205).

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Boyanovsky , H. J. de Vega , R. Holman

According to the most popular scenario, the early Universe should have experienced an accelerated expansion phase, called Cosmological Inflation, after which the standard Big Bang Cosmology would have taken place giving rise to the…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-03 Alessandro Di Marco , Gianfranco Pradisi , Giancarlo de Gasperis , Paolo Cabella

This paper considers Einstein-Brans-Dicke action being coupled with a Higgs sector. It is shown that classically graceful exit from inflation is not possible in principle, rejecting the claim of La and Steinhardt. Further, wormhole…

High Energy Physics - Theory · Physics 2017-07-26 Abhik Kumar Sanyal , Bijan Modak