Exploring hybrid scalar factor and ekpyrotic bouncing cosmology in f(Q,R) Gravity

IF 1.6 3区物理与天体物理 Q3 PHYSICS, FLUIDS & PLASMAS

High Energy Density Physics Pub Date : 2025-03-28 DOI:10.1016/j.hedp.2025.101188

Aimen Rauf , Bander Almutairi , A.S. Khan

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引用次数: 0

Abstract

In this study, we delve into the evolution of the Hubble parameter, focusing on its sign reversal in the early universe and its stability within

f (Q, R)

gravity. Methods are employed to investigate the universe’s behavior concerning hybrid scale factor scenarios, including the sub-relativistic, radiation, ultra-relativistic, dust, and stiff fluid universes, concerning the equation of state (EoS) parameters. This research builds on previous ones by providing a more in-depth investigation of the bouncing scenarios inside the

f (Q, R)

gravity framework, reconstructing gravitational Lagrangians established for certain parameter values. Once rebuilt, these Lagrangians allow the examination of energy conditions required for a realistic bouncing model and give analytical answers to the ekpyrotic (Ekkart) bounce model. The function of exotic matter, renowned for its high negative pressure, is the key factor promoting the universe’s acceleration expansion. An analysis of

f (Q, R)

gravity theories, particularly focusing on bouncing scenarios, distinguishes this work from earlier studies on alternative gravity theories and their cosmological implications. This research offers a detailed investigation of bouncing models along with a detailed examination of the energy conditions present in

f (Q, R)

gravity.

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来源期刊

High Energy Density Physics PHYSICS, FLUIDS & PLASMAS-

CiteScore

4.20

自引率

6.20%

发文量

审稿时长

6-12 weeks

期刊介绍： High Energy Density Physics is an international journal covering original experimental and related theoretical work studying the physics of matter and radiation under extreme conditions. ''High energy density'' is understood to be an energy density exceeding about 1011 J/m3. The editors and the publisher are committed to provide this fast-growing community with a dedicated high quality channel to distribute their original findings. Papers suitable for publication in this journal cover topics in both the warm and hot dense matter regimes, such as laboratory studies relevant to non-LTE kinetics at extreme conditions, planetary interiors, astrophysical phenomena, inertial fusion and includes studies of, for example, material properties and both stable and unstable hydrodynamics. Developments in associated theoretical areas, for example the modelling of strongly coupled, partially degenerate and relativistic plasmas, are also covered.