Accelerately Expanding Cosmologies in f(R,Φ,X) Theory

Authors : Erkan ERASLAN, Melis ULU DOĞRU

Pages : 331-336

Doi:10.19113/sdufenbed.1256169

View : 58 | Download : 42

Publication Date : 2023-08-25

Article Type : Research Paper

Abstract :In this study, beginning and today expansion of universe are viewed in finsert ignore into journalissuearticles values(R,Φ,X); gravity. Field equations and their solutions of Friedmann-Lemaître-Robertson-Walker cosmologies with perfect fluid are obtained by considering finsert ignore into journalissuearticles values(R,Φ,X);=f_0 R+f_1 X^q-Vinsert ignore into journalissuearticles values(Φ); model. Validity of both finsert ignore into journalissuearticles values(R,Φ,X); gravity and finsert ignore into journalissuearticles values(R,Φ,X);=f_0 R+f_1 X^q-Vinsert ignore into journalissuearticles values(Φ); model for non-static space-time geometries is discussed by making use of the obtained matter dynamics results such as pressure and energy density. It is seen that in all obtained solutions by taking into account early and late period expansion, f function is a constant. This indicates that finsert ignore into journalissuearticles values(R,Φ,X); function is a first-order dependent function of Ricci scalar. When finsert ignore into journalissuearticles values(R,Φ,X);=f_0 R+f_1 X^q-Vinsert ignore into journalissuearticles values(Φ); model is considered together, it is understood that the obtained solutions could be reduced to Λ-CDM model for finsert ignore into journalissuearticles values(R); gravity in limits of Φ→0 and X→0. The fact that the obtained results agree with expected situations supports. So, finsert ignore into journalissuearticles values(R,Φ,X); theory is a consistent theory of gravity.
Keywords : f R Φ X, Gravite, İdeal akışkan, Friedmann Lemaître Robertson Walker Uzay Zamanı