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We propose a model for cosmic inflation which is based on an effective description of strongly interacting, nonsupersymmetric matter within the framework of dynamical abelian projection and centerization. The underlying gauge symmetry is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ralf Hofmann , Mathias Th. Keil

Cosmic inflation is arguably the most favoured paradigm of the very early Universe. It postulates an early phase of fast, nearly exponential, and accelerated expansion. Inflationary models are capable of explaining the overall flatness and…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-08 Cristian Joana

The inflationary scenarios suggested by the duality properties of string cosmology in the Brans-Dicke (or String) frame are shown to correspond to accelerated contraction (deflation) when Weyl-transformed to the Einstein frame. We point out…

High Energy Physics - Theory · Physics 2009-10-22 M Gasperini , G Veneziano

We show that the entropy of cosmological perturbations originating as quantum vacuum fluctuations in the very early universe, including the contribution of the leading nonlinear interactions, can be viewed as momentum space entanglement…

High Energy Physics - Theory · Physics 2020-11-12 Suddhasattwa Brahma , Omar Alaryani , Robert Brandenberger

The vacuum inflation with a boundary condition specified at a short-distance scale in a generally primeval non-flat Universe, and implications of the correspondingly modified primordial power spectrum via the WMAP data are investigated. We…

Astrophysics · Physics 2009-09-28 Jie Ren , Hong-Guang Zhang , Xin-He Meng

We propose a model for cosmic inflation which is based on an effective description of strongly interacting, nonsupersymmetric matter within the framework of dynamical Abelian projection and centerization. The underlying gauge symmetry is…

High Energy Physics - Phenomenology · Physics 2009-11-07 Ralf Hofmann , Mathias Th. Keil

We study how the initial inhomogeneities of the spatial curvature affect the onset of inflation in the closed universe. We consider a cosmological model which contains a radiation and a cosmological constant. In order to treat the…

General Relativity and Quantum Cosmology · Physics 2011-07-19 O. Iguchi , H. Ishihara , J. Soda

We investigate the nucleation of circular cosmic strings in models of generalized inflationary universes with an accelerating scale factor. We consider toy cosmological models of a smooth inflationary exit and transition into a flat…

High Energy Physics - Theory · Physics 2011-05-23 Minos Axenides , Arne L. Larsen

We study the implications of the recently proposed Trans-Planckian Censorship Conjecture (TCC) for early universe cosmology and in particular inflationary cosmology. The TCC leads to the conclusion that if we want inflationary cosmology to…

High Energy Physics - Theory · Physics 2020-05-06 Alek Bedroya , Robert Brandenberger , Marilena Loverde , Cumrun Vafa

It is conjectured that inflation, taking account of quantum gravity, leads to a discrete spectrum of cosmological perturbations, instead of the continuous Gaussian spectrum predicted by standard field theory in an unquantized background.…

Astrophysics · Physics 2009-11-10 Craig J. Hogan

If the cosmological inflationary scenario took place in the cosmic landscape in string theory, the inflaton, the scalar mode responsible for inflation, would have meandered in a complicated multi-dimensional potential. We show that this…

High Energy Physics - Theory · Physics 2010-01-21 S. -H. Henry Tye , Jiajun Xu

Topologically protected sheet-like surfaces, called domain walls, form when the potential of a field has a discrete symmetry that is spontaneously broken. Since this condition is commonplace in field theory, it is plausible that many of…

High Energy Physics - Phenomenology · Physics 2018-12-07 Cyrus Faroughy

Overall, brane inflation is compatible with the recent analysis of the WMAP data. Here we explore the constraints of WMAP and 2dFGRS data on the various brane inflationary scenarios. Brane inflation naturally ends with the production of…

High Energy Physics - Theory · Physics 2014-11-18 Levon Pogosian , S. -H. Henry Tye , Ira Wasserman , Mark Wyman

When cosmic strings are formed during inflation, they regrow to reach a scaling regime, leaving distinct imprints on the stochastic gravitational wave background (SGWB). Such signatures, associated with specific primordial features, can be…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-18 Mainak Baidya , Anish Ghoshal , David F. Mota

String gas cosmology is a string theory-based approach to early universe cosmology which is based on making use of robust features of string theory such as the existence of new states and new symmetries. A first goal of string gas cosmology…

High Energy Physics - Theory · Physics 2008-08-07 Robert H. Brandenberger

We compute the power spectrum of curvature perturbations in stochastic inflation. This combines the distribution of first crossing times through the end-of-inflation surface, which has been previously studied, with the distribution of the…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-27 Kenta Ando , Vincent Vennin

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

Inflationary string cosmology backgrounds can amplify perturbations in a more efficient way than conventional inflationary backgrounds, because the perturbation amplitude may grow - instead of being constant - outside the horizon. If not…

High Energy Physics - Theory · Physics 2007-05-23 M. Gasperini

A period of rapidly accelerating expansion is expected in the early Universe implemented by a scalar field slowly rolling down along an asymptotically flat potential preferred by the current data. In this paper, we point out that this…

General Relativity and Quantum Cosmology · Physics 2022-09-01 Rong-Gen Cai , Yu-Shi Hao , Shao-Jiang Wang

Pre--big bang models of inflation based on string cosmology produce a stochastic gravitational wave background whose spectrum grows with decreasing wavelength, and which may be detectable using interferometers such as LIGO. We point out…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Edmund J Copeland , Andrew R Liddle , James E Lidsey , David Wands