Barrow HDE model for Statefinder diagnostic in non-flat FRW universe

The objective of the present paper is to investigate an almost-pseudo-Ricci symmetric FRW spacetime with a constant Ricci scalar in a dynamic cosmological term Λ(t) and equation of state (EoS) ω(t) scenario. Several cosmological parameters are calculated in this setting and thoroughly studied, which shows that the model satisfies the late-time accelerating expansion of the universe. We also examine all of the energy conditions to check our model’s self-stability.

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Thermodynamics of the Apparent Horizon in FRW Universe with Massive Gravity

Communications in Theoretical Physics ◽

10.1088/0253-6102/60/1/05 ◽

2013 ◽

Vol 60 (1) ◽

pp. 28-36 ◽

Cited By ~ 2

Author(s):

Hui Li ◽

Yi Zhang

Keyword(s):

Apparent Horizon ◽

Massive Gravity ◽

Frw Universe

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Dynamical system analysis of interacting variable modified Chaplygin gas model in FRW universe

The European Physical Journal Plus ◽

10.1140/epjp/i2012-12030-2 ◽

2012 ◽

Vol 127 (3) ◽

Cited By ~ 6

Author(s):

J. Bhadra ◽

U. Debnath

Keyword(s):

Dynamical System ◽

System Analysis ◽

Chaplygin Gas ◽

Modified Chaplygin Gas ◽

Frw Universe ◽

Variable Modified Chaplygin Gas

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An effective cosmological constant from an entropic formulation of gravity

International Journal of Modern Physics D ◽

10.1142/s0218271820500649 ◽

2020 ◽

Vol 29 (09) ◽

pp. 2050064

Author(s):

I. Díaz-Saldaña ◽

J. C. López-Domínguez ◽

M. Sabido

Keyword(s):

Cosmological Constant ◽

Apparent Horizon ◽

Friedmann Equation ◽

Scale Factor ◽

Late Time ◽

Frw Universe ◽

Equation Solving ◽

Effective Cosmological Constant ◽

Time Regime ◽

Modified Entropy

In this work, we study a Friedmann–Robertson–Walker (FRW) universe derived from a modified entropy–area relationship. By applying the first law of thermodynamics to the so-called apparent horizon and a modified entropy–area relationship, we obtain a modified Friedmann equation. Solving this model for a perfect fluid with vanishing cosmological constant, we find that for early times, the scale factor is the same as that of an FRW universe. In the late-time regime, although the cosmological constant is zero, the asymptotic behavior of the scale factor is exponential, and therefore, we can identify an effective cosmological constant. The origin of the effective cosmological constant can be traced to the modifications of the entropy–area relation.

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On the varying speed of light in a brane-induced FRW universe

Journal of High Energy Physics ◽

10.1088/1126-6708/2000/11/017 ◽

2000 ◽

Vol 2000 (11) ◽

pp. 017-017 ◽

Cited By ~ 28

Author(s):

Stephon H.S Alexander

Keyword(s):

Speed Of Light ◽

Frw Universe

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RADION POTENTIAL AND BRANE DYNAMICS

Modern Physics Letters A ◽

10.1142/s0217732301004911 ◽

2001 ◽

Vol 16 (24) ◽

pp. 1583-1595 ◽

Cited By ~ 8

Author(s):

L. MERSINI

Keyword(s):

Inflation Rate ◽

Vacuum Energy ◽

Density Perturbation ◽

Scalar Fields ◽

Fine Tuning ◽

Late Time ◽

Frw Universe ◽

Strong Suppression ◽

Dynamic Setting ◽

The Universe

We examine the cosmology of Randall–Sundrum model in a dynamic setting where scalar fields are present in the bulk as well as the branes. This generates a mechanism similar to that of Goldberger–Wise for radion stabilization and the recovery of late-time cosmology features on the branes. Due to the induced radion dynamics, the inflating branes roll towards the minimum of the radion potential, thereby exiting inflation and reheating the universe. In the slow roll part of the potential, the TeV branes have maximum inflation rate and energy as their coupling to the radion and bulk modes have minimum suppression. Hence, when rolling down the steep end of the potential towards the stable point, the radion field (which appears as the inflaton of the effective 4-D theory in the branes) decays very fast and reheats the universe. This process results in a decrease of the brane's canonical vacuum energy, Λ4. However, at the minimum of the potential Λ4 is small but not necessarily zero and the fine-tuning issue remains. Density perturbation constraints introduce an upper bound on Λ4. Due to the large radion mass and strong suppression to the bulk modes, moduli problems and bulk reheating do not occur. The reheat temperature and a sufficient number of e-folding constraints for the brane-universe are also satisfied. The model therefore recovers the radiation dominated FRW universe.

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