2024 : 5 : 29

Jafar Sadeghi

Academic rank: Professor
ORCID:
Education: PhD.
ScopusId:
Faculty: Science
Address:
Phone: 9111125092

Research

Title
Further refining swampland dS conjecture in mimetic f(G) gravity
Type
JournalPaper
Keywords
Mimetic f(G) gravity; further refining swampland dS conjecture
Year
2023
Journal INTERNATIONAL JOURNAL OF MODERN PHYSICS D
DOI
Researchers saeed noori gashti ، Jafar Sadeghi ، m.r. Alipour

Abstract

Mimetic gravity analysis has been studied as a theory in various types of general relativity extensions, such as mimetic f(R) gravity, mimetic f(R, T) gravity, mimetic f(R, G) gravity, etc. in the literature. This paper presents a set of equations arising from mimetic conditions and studies cosmic inflation with a combination of mimetic f(G) gravity and swampland dS conjectures. We analyze and evaluate these results. Therefore, we first thoroughly introduce the mimetic f(G) gravity and calculate some cosmological parameters such as the scalar spectral index, the tensor-to-scalar ratio, and the slow-roll parameters. Also, we investigate the potential according to the mimetic f(G) gravity. Then we will challenge the swampland dS conjectures with this condition. By expressing the coefficient of swampland dS conjectures viz C1 and C2 in terms of ns and r, we plot some figures and determine the allowable range for each of these cosmological parameters and these coefficients, and finally, compare these results with observable data such as Planck and BICEP2/Keck array data. We show C1 and C2 are not O(1), so the refining swampland dS conjecture is not satisfied for this inflationary model. Then we examine it with further refining swampland dS conjecture, which has a series of free parameters such as a, b > 0, q > 2 and a + b = 1. By adjusting these parameters, the compatibility of the mentioned conjecture with the inflationary model can be discussed. We determine the further refining swampland dS conjecture is satisfied. when a < 1 1.00489 = 0.99513, we can always find a, b and q whose value is larger than 2, viz for q = 2.4, we find 0.99185 ≤ a < 1, which we can choose a = 0.99235 according to the condition a < 0.99513. Also we know b = 1−a, so we will have 1−0.99235 = 0.00765 > 0.