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Related papers: Viable Intermediate Inflation in the Mimetic DBI M…

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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

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

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

We consider the mimetic tachyon model in the Lagrange multiplier approach. We study both the linear and non-linear perturbations and find the perturbation and non-gaussianity parameters in this setup. By adopting two types of the scale…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-05 Narges Rashidi , Kourosh Nozari

In this paper, we study a curvaton model described by a Dirac-Born-Infeld-like action. We calculate the spectrum of curvature perturbation induced by DBI-curvaton and estimate its non-Gaussianity. We find that in the limit of low sound…

High Energy Physics - Phenomenology · Physics 2009-01-24 Sheng Li , Yi-Fu Cai , Yun-Song Piao

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

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

An analysis is given of inflation based on a supersymmetric Dirac-Born-Infeld (DBI) action in an axionic landscape. The DBI model we discuss involves a landscape of chiral superfields with one $U(1)$ shift symmetry which is broken by…

High Energy Physics - Phenomenology · Physics 2019-02-20 Pran Nath , Maksim Piskunov

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

The scalar-tensor Dirac-Born-Infeld (DBI) inflation scenario provides a simple mechanism to reduce the large values of the boost factor associated with single field models with DBI action, whilst still being able to drive 60 efolds of…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-04 Joel M. Weller , Carsten van de Bruck , David F. Mota

We study cosmological perturbations in general inflation models with multiple scalar fields and arbitrary kinetic terms, with special emphasis on the multi-field extension of Dirac-Born-Infeld (DBI) inflation. We compute the second-order…

High Energy Physics - Theory · Physics 2008-12-18 David Langlois , Sebastien Renaux-Petel , Daniele A. Steer , Takahiro Tanaka

We propose a warm inflationary model in the context of relativistic D-brane inflation in a warped throat, which has Dirac-Born-Infeld (DBI) kinetic term and is coupled to radiation through a dissipation term. The perturbation freezes at the…

High Energy Physics - Theory · Physics 2011-05-23 Yi-Fu Cai , James B. Dent , Damien A. Easson

We study the inflation in a model with a Gauss-Bonnet term which is non-minimally coupled to a DBI field. We study the spectrum of the primordial perturbations in detail. The non-Gaussianity of this model is considered and the amplitude of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Kourosh Nozari , Narges Rashidi

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 consider a model of two-field inflation, containing an ordinary scalar field and a DBI field. We work beyond the slow-roll approximation, but we assume a separable Hubble parameter. We then derive the form of potential in this framework…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-25 Kourosh Nozari , Kosar Asadi

In scalar-tensor theories the scalar fields generically couple nontrivially to gravity. We study the observable properties of inflationary models with non-minimally coupled inflaton and Dirac-Born-Infeld (DBI) kinetic term. Within the…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Damien A. Easson , Shinji Mukohyama , Brian A. Powell

In this work we consider a DBI Galileon (DBIG) inflationary model and constrain its parameter space with the Planck 2015 and BICEP2/Keck array and Planck (BKP) joint analysis data by means of a potential independent analysis. We focus our…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-01 K. Sravan Kumar , Juan C. Bueno Sanchez , Celia Escamilla-Rivera , Joao Marto , Paulo Vargas Moniz

We analyze the spectrum of density perturbations generated in models of the recently discovered "D-cceleration" mechanism of inflation. In this scenario, strong coupling quantum field theoretic effects sum to provide a DBI-like action for…

High Energy Physics - Theory · Physics 2009-11-10 Mohsen Alishahiha , Eva Silverstein , David Tong

We study the bispectrum of the primordial curvature perturbation on uniform-density hypersurfaces generated by a kind of the noncanonical warm inflation, wherein the inflation is provided by a noncanonical scalar inflaton field that is…

General Relativity and Quantum Cosmology · Physics 2015-04-09 Xiao-Min Zhang , Jian-Yang Zhu

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
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