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Related papers: DBI Galileon inflation in the light of Planck 2015

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We investigate intermediate inflation in the framework of a Galileon scalar field. To this aim, we first obtain the inflationary observables, including the scalar spectral index, the tensor-to-scalar ratio, the running of the scalar…

General Relativity and Quantum Cosmology · Physics 2018-09-03 Zeinab Teimoori , Kayoomars Karami

Picking out DBI scalar field as inflation, the slow-rolling inflationary scenario is studied by attributing an exponential time function to scale factor; known as intermediate inflation. The perturbation parameters of the model are…

General Relativity and Quantum Cosmology · Physics 2017-08-15 N. Nazavari , A. Mohammadi , Z. Ossoulian , Kh. Saaidi

In the previous work, a new kind of inflation model was proposed, which has the interesting property that its perturbation equation of motion gets a correction of k^4, due to the non-linearity of the kinetic term. Nonetheless, the…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-16 Jun Chen , Hou Wenjie , Defu Hou , Taotao Qiu

Very few explicit inflationary scenarios are known to generate a large bispectrum of orthogonal shape. Dirac-Born-Infeld Galileon inflation, in which an induced gravity term is added to the DBI action, is one such model. We formulate it in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Sebastien Renaux-Petel

We introduce a model of potential driven DBI Galileon inflation in background N=1,D=4 SUGRA. Starting from D4-$\bar{D4}$ brane-antibrane in the bulk N=2,D=5 SUGRA including quadratic Gauss-Bonnet corrections, we derive an effective N=1,D=4…

High Energy Physics - Theory · Physics 2015-03-20 Sayantan Choudhury , Supratik Pal

We propose a new class of inflation model, G-inflation, which has a Galileon-like nonlinear derivative interaction of the form $G(\phi, (\nabla\phi)^2)\Box\phi$ in the Lagrangian with the resultant equations of motion being of second order.…

High Energy Physics - Theory · Physics 2010-12-28 Tsutomu Kobayashi , Masahide Yamaguchi , Jun'ichi Yokoyama

We investigate the power-law, intermediate, and logamediate inflationary models in the framework of DBI non-canonical scalar field with constant sound speed. In the DBI setting, we first represent the power spectrum of both scalar density…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-20 Roonak Amani , Kazem Rezazadeh , Asrin Abdolmaleki , Kayoomars Karami

We study a particular Galileon inflation in the light of Planck2015 observational data in order to constraint the model parameter space. We study the spectrum of the primordial modes of the density perturbations by expanding the action up…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Kosar Asadi , Kourosh Nozari

A new modified string-inspired modular invariant supergravity model is proposed and is applied to realize the slow roll inflation in Einstein frame. Because inflation deals with Planck scale physics, the dilaton can be a strong candidate…

High Energy Physics - Phenomenology · Physics 2011-04-22 Mitsuo J. Hayashi , Yuta Koshimizu , Toyokazu Fukuoka , Kenji Takagi , Hikoya Kasari

We consider an intermediate Dirac-Born-Infeld (DBI) inflationary model in the presence of a minimal measurable length in the theory. We show that, the presence of a minimal measurable length modifies the definitions of the scalar and tensor…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-02 Narges Rashidi , Maryam Roushan , Kourosh Nozari

We study inflation with the Dirac-Born-Infeld (DBI) noncanonical scalar field in both the cold and warm scenarios. We consider the Anti-de Sitter warp factor $f(\phi)=f_{0}/\phi^{4}$ for the DBI inflation and check viability of the quartic…

General Relativity and Quantum Cosmology · Physics 2019-02-05 S. Rasouli , K. Rezazadeh , A. Abdolmaleki , K. Karami

We reconsider a recently proposed warm G-inflation scenario in which the Galileon scalar field concurrently dissipates its kinetic energy as the radiation fluid throughout inflation and the universe smoothly enters into a radiation…

General Relativity and Quantum Cosmology · Physics 2018-11-15 Maysam Motaharfar , Erfan Massaeli , Hamid Reza Sepangi

A new class of inflation models within the context of G-inflation is proposed, in which the standard model Higgs boson can act as an inflaton thanks to Galileon-like non-linear derivative interaction. The generated primordial density…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-05 Kohei Kamada , Tsutomu Kobayashi , Masahide Yamaguchi , Jun'ichi Yokoyama

We identify models of supersymmetric hybrid inflation in which the tensor-to-scalar ratio, a canonical measure of gravity waves produced during inflation, can be as large as 0.03 or so, which will be tested by the Planck satellite…

High Energy Physics - Phenomenology · Physics 2011-03-07 Qaisar Shafi , Joshua R. Wickman

In this work, we study an inflationary scenario in the presence of Generalized Chaplygin Gas (GCG). We show that in Einstein gravity, GCG is not a suitable candidate for inflation; but in a five dimensional brane world scenario, it can work…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-22 Bikash R Dinda , Sumit Kumar , Anjan A. Sen

We study mimetic gravity in the presence of a DBI-like term which is a non-canonical setup of the scalar field's derivatives. We consider two general cases with varying and constant sound speeds and construct the potentials for both the DBI…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-13 Kourosh Nozari , Narges Rashidi

An upper bound on the amplitude of the primordial gravitational wave spectrum generated during ultra-violet DBI inflation is derived. The bound is insensitive to the form of the inflaton potential and the warp factor of the compactified…

High Energy Physics - Theory · Physics 2008-11-26 James E. Lidsey , Ian Huston

We study inflation in the Brans-Dicke gravity as a special model of the scalar-tensor gravity. We obtain the inflationary observables containing the scalar spectral index, the tensor-to-scalar ratio, the running of the scalar spectral index…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-06 B. Tahmasebzadeh , K. Rezazadeh , K. Karami

We discuss a supersymmetric version of DBI (Dirac-Born-Infeld) inflation, which is a typical inflation model in string cosmology. The supersymmetric DBI action together with a superpotential always leads to correction terms associated with…

High Energy Physics - Theory · Physics 2015-06-05 Shin Sasaki , Masahide Yamaguchi , Daisuke Yokoyama

We discuss a mechanism of particle production during inflation that can result in a blue gravitational wave (GW) spectrum, compatible with the BICEP2 result and with the r < 0.11 limit on the tensor-to-scalar ratio at the Planck pivot…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Shinji Mukohyama , Ryo Namba , Marco Peloso , Gary Shiu
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