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Related papers: The generalized Chaplygin-Jacobi gas

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The generalized Chaplygin gas (GCG) model allows for an unified description of the cosmologically recent accelerated expansion of the Universe and of the evolution of energy density perturbations. This dark energy - dark matter unification…

Astrophysics · Physics 2007-05-23 O. Bertolami

In this paper we discuss the inflationary universe in the context of a Chaplygin gas equation of state within the framework of the effective theory of loop quantum cosmology. Under the slow-roll approximation, we calculate the primordial…

General Relativity and Quantum Cosmology · Physics 2009-08-20 Xin Zhang , Jingfei Zhang , Jinglei Cui , Li Zhang

In this work, we discuss the de Sitter swampland conjectures in the context of the generalized Chaplygin-inspired inflationary model. We demonstrate that these conjectures can be satisfied, but only in the region of the parameter space far…

General Relativity and Quantum Cosmology · Physics 2024-10-08 Orfeu Bertolami , Robertus Potting , Paulo M. Sá

Nonminimal coupling of the inflaton field to the Ricci curvature of spacetime is generally unavoidable, and the paradigm of inflation should be generalized by including the corresponding term in the Lagrangian of the inflationary theory.…

High Energy Physics - Theory · Physics 2014-11-18 Valerio Faraoni

We have developed an action formulation for the Generalized Chaplygin Gas (GCG). The most general form for the nonrelativistic GCG action is derived consistent with the equation of state. We have also discussed a relativistic formulation…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Rabin Banerjee , Subir Ghosh , Shailesh Kulkarni

In this paper, we examine the possible realization of a new family of inflation called "shaft inflation" by assuming the modified Chaplygin gas model and tachyon scalar field. We also consider the special form of dissipative coefficient as…

General Relativity and Quantum Cosmology · Physics 2017-03-08 Abdul Jawad , Amara Ilyas , Shamaila Rani

It has been shown that sub-Planckian models of inflation require initial homogeneity on super-Hubble scales under certain commonly held assumptions. Here I remark on the possible implications of this result for inflationary cosmology.

Astrophysics · Physics 2009-10-31 Tanmay Vachaspati

The generalized Chaplygin gas model represents an attempt to unify dark matter and dark energy. It is characterized by a fluid with an equation of state $p = - A/\rho^\alpha$. It can be obtained from a generalization of the DBI action for a…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 J. C. Fabris , T. C. C. Guio , M. Hamani Daouda , O. F. Piattella

Warm inflationary universe models in the context of generalized chaplygin gas, modified chaplygin gas, generalized cosmic chaplygin gas are being studied. The dissipative coefficient of the form $\Gamma\propto T$, weak and strong…

General Relativity and Quantum Cosmology · Physics 2016-10-27 Abdul Jawad , Sadaf Butt , Shamaila Rani

We clarify thermodynamics of the Chaplygin gas by introducing the integrability condition. All thermal quantities are derived as functions of either volume or temperature. Importantly, we find a new general equation of state, describing the…

General Relativity and Quantum Cosmology · Physics 2011-09-12 Yun Soo Myung

Brane inflationary universe model in the context of a Chaplygin gas equation of state is studied. General conditions for this model to be realizable are discussed. In the high-energy limit and by using a chaotic potential we describe in…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ramon Herrera

We derive a general criterion that defines all single-field models leading to Starobinsky-like inflation and to universal predictions for the spectral index and tensor-to-scalar ratio, which are in agreement with Planck data. Out of all the…

High Energy Physics - Phenomenology · Physics 2015-06-18 Gian F. Giudice , Hyun Min Lee

The generalized Chaplygin gas (GCG) model allows for an unified description of the recent accelerated expansion of the Universe and the evolution of energy density perturbations. This dark energy - dark matter unification is achieved…

General Relativity and Quantum Cosmology · Physics 2014-11-17 M. C. Bento , O. Bertolami , A. A. Sen

We provide an explicit calculation of the evolution of the cosmic entanglement entropy in the early universe before the matter dominant era. This is made possible by invoking the generalized Chaplygin gas (GCG) model, which has the…

General Relativity and Quantum Cosmology · Physics 2011-12-08 Pisin Chen , Yuezhen Niu

In this paper we study a quintessence cosmological model in which the dark energy component is considered to be the Generalized Chaplygin Gas and the curvature of the three-geometry is taken into account. Two parameters characterize this…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Sergio del Campo , José Villanueva

We consider a type of k-inflation under the Hamilton-Jacobi approach. We calculate various observables such as the scalar power spectrum, the tensor-to-scalar ratio, the scalar spectra index for the case where the Hubble parameter is a…

General Relativity and Quantum Cosmology · Physics 2024-06-27 Rong-Jia Yang , Ming Liu

We explore two saddle point inflationary scenarios in the context of higher order corrections related to different generalisations of general relativity. Firstly, we deal with Jordan frame Starobinsky potential, for which we identify a…

High Energy Physics - Theory · Physics 2016-02-17 Michal Artymowski , Zygmunt Lalak , Marek Lewicki

The generalized Chaplygin gas provides an interesting candidate for the present accelerated expansion of the universe. We explore a geometrical explanation for the generalized Chaplygin gas within the context of brane world theories where…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Heydari-Fard , H. R. Sepangi

Inflationary cosmology has made significant strides in understanding the physics driving the rapid expansion of the early universe. However, many inflation models with diverse potential shapes present analysis, comparison, and…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-25 Somnath Das , P K Suresh

We consider scalar field inflation in the Palatini formulation of general relativity. The covariant derivative of the metric is then non-zero. From the effective theory point of view it should couple to other fields. We write down the most…

General Relativity and Quantum Cosmology · Physics 2022-05-04 Syksy Rasanen