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Khaled Saaidi

Khaled Saaidi

Academic rank: Professor
ORCID:
Education: PhD.
ScopusId: 4567832
Faculty: Faculty of Science
Address: Department of Physics, Faculty of Science, University of Kurdistan, Pasdaran Street, Sanandaj, Kurdistan, Iran. 2th Address: Science and Technology Park of Kurdistan, Buo Ali Boolvar, Ghane Square, Baharan Town , Sanandaj, Kurdistan, Iran.
Phone: 08733776900

Research

Title
Anisotropic inflation in Brans–Dicke gravity
Type
JournalPaper
Keywords
Brans-Dicke Gravity; Anisotropic inflation
Year
2017
Journal NUCLEAR PHYSICS B
DOI
Researchers Mehraneh Tirandari ، Khaled Saaidi

Abstract

We study anisotropic inflation in the Brans–Dicke gravity in the presence of an abelian gauge field where the gauge field is non-minimally coupled to the inflaton. We show that the degree of anisotropy, under slow-roll approximations, is proportional to slow-roll parameter of the theory. As a demonstration, we consider the displaced quadratic potential for the inflation. We do the numerical calculation of the model to investigate the behavior of anisotropy by changing the parameter in the Brans–Dicke model. We find out that, the solution is an attractor in the phase space, and anisotropy grows with the number of e-folds. Anisotropy depends on the Brans–Dicke parameter, ω, initial values of the scalar field and constant parameter of the coupling function of the scalar field and the abelian gauge field, c. If we consider upper bound on the number of e-folds from CMB i.e. 60e-folds, by increasing ωand c, anisotropy do not have time to exit the horizon and it is suppressed.