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Related papers: Inflation from a Tachyon Fluid?

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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

Multiple axions form a landscape in the presence of various shift symmetry breaking terms. Eternal inflation populates the axion landscape, continuously creating new universes by bubble nucleation. Slow-roll inflation takes place after the…

High Energy Physics - Phenomenology · Physics 2015-04-14 Tetsutaro Higaki , Fuminobu Takahashi

We define a new inflationary scenario in which inflation starts naturally after the Big Bang when the energy density drops below some critical value. As a model, we use recently proposed symmetron field whose effective potential depends on…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-02 Ruifeng Dong , William H. Kinney , Dejan Stojkovic

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

The emergent model in the context of loop quantum cosmology with a tachyon scalar field is studied. We find that there is a center equilibrium point in the semiclassical region and a saddle point in the classical region. If the potential of…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-28 Puxun Wu , Shuang Nan Zhang , Hongwei Yu

An intermediate inflationary universe model in the context of a generalized Chaplygin gas is considered. For the matter we consider two different energy densities; a standard scalar field and a tachyon field, respectively. In general, we…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Ramon Herrera , Marco Olivares , Nelson Videla

Cosmic inflation provides a window to the highest energy densities accessible in nature, far beyond those achievable in any realistic terrestrial experiment. Theoretical insights into the inflationary era and its observational probes may…

The open inflation model recently proposed by Hawking and Turok is investigated in scalar-tensor gravity context. If the dilaton-like field has no potential, the instanton of our model is singular but has a finite action. The…

High Energy Physics - Theory · Physics 2016-08-25 Jae-weon Lee , Seoktae Koh , Chul H. Lee

In this paper, we study the dynamics of the Chern-Simons Inflation Model proposed by Alexander, Marciano and Spergel. According to this model, inflation begins when a fermion current interacts with a turbulent gauge field in a space larger…

General Relativity and Quantum Cosmology · Physics 2014-04-01 David Garrison

We perform a numerical investigation of the field evolution in the smooth hybrid inflationary model. We find that for almost all the examined initial values we do get an adequate amount of inflation. Our results show that the model is…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Lazarides , C. Panagiotakopoulos , N. D. Vlachos

We provide an explicit solution representing an anisotropic power law inflation within the framework of rolling tachyon model. This is generated by allowing a non-minimal coupling between the tachyon and the world-volume gauge field on…

High Energy Physics - Theory · Physics 2012-01-25 Samrat Bhowmick , Sudipta Mukherji

In the past decade, the importance of dissipation and fluctuation to inflationary dynamics has been realized and has led to a new picture of inflation called warm inflation. Although these phenomena are common to condensed matter systems,…

High Energy Physics - Phenomenology · Physics 2009-11-13 Arjun Berera

I generalize the inflationary flow equations of Hoffman and Turner to arbitrary order in slow roll. This makes it possible to study the predictions of slow roll inflation in the full observable parameter space of tensor/scalar ratio $r$,…

Astrophysics · Physics 2009-11-07 William H. Kinney

Inflation is the currently accepted paradigm for the beginnings of the Universe. To explain the observed almost scale invariant spectrum of density perturbations with only a slight spectral tilt, inflation must have been "slow roll", that…

High Energy Physics - Theory · Physics 2021-01-07 Hao Geng

We present a model of inflation where the inflaton is accommodated as a phantom field which exhibits an initial transient pole behavior and then decays into a quintessence field which is responsible for a radiation era. We must stress that…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Martin G. Richarte , Gilberto M. Kremer

Inflation in the early Universe is one of the most promising probes of gravity in the high-energy regime. However, observable scales give access to a limited window in the inflationary dynamics. In this essay, we argue that quantum…

High Energy Physics - Theory · Physics 2017-11-22 Robert J. Hardwick , Vincent Vennin , David Wands

Quintessential inflation is studied using a string modulus as the inflaton - quintessence field. The modulus begins its evolution at the steep part of its scalar potential, which is due to non-perturbative effects (e.g. gaugino…

High Energy Physics - Theory · Physics 2008-11-26 J. C. Bueno Sanchez , K. Dimopoulos

We study chaotic inflation driven by a real, massive, homogeneous minimally coupled scalar field in a flat Robertson-Walker spacetime. The semiclassical limit for gravity is considered, whereas the scalar field is treated quantum…

General Relativity and Quantum Cosmology · Physics 2008-11-26 F. Finelli , G. P. Vacca , G. Venturi

In this work we investigate the effect of a kind of scalar field, called chameleon, on the evolution of universe. We put this scalar field in the bulk. It is displayed that this scalar field gives us an exponential expansion in early time…

General Physics · Physics 2014-01-17 Khaled Saaidi , AbolHassan Mohammadi

Inflation is considered to be the best paradigm for describing the early universe. However, it is still unclear what is the nature of the field which drives inflation. In this talk, we discuss the possibility of spinor field driving…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-05 S. Shankaranarayanan