Abstract The cosmological dynamics are rigorously investigated through the systematic application of autonomous system analysis to gravitational field equations in non-metricity gravity. procedure analyze late-time cosmic acceleration higher-order gravity is demonstrated by exploring non-hyperbolic critical points with center manifold theory. stability properties these also evaluated based on eigenvalues and phase portraits. It explicitly shown that stable node can be realized. each model...

In recent years, the modified theory of gravity known as $f(Q)$ has drawn interest a potential alternative to general relativity. According this theory, gravitational force is determined by function so-called ``non-metricity" tensor $Q$, which expresses how far particle space-time from metric geometry. contrast relativity, describes field using curvature tensor, builds non-metricity tensor. For class theories, dynamical system analysis background and perturbation equations been carried out...

Modified gravity theories have received increased attention lately to understand the late time acceleration of universe. This viewpoint essentially modifies geometric components Among numerous extension Einstein's theory gravity, which include higher order curvature invariant, and specifically class $f(R)$ theories, several acknowledgments. In our current work we try universe by modifying geometry space using dynamical system analysis. The use this technique allows behavior under...

The higher-curvature gravity with boundary terms i.e the $f(Q)$ theories, grounded on non-metricity as a fundamental geometric quantity, exhibit remarkable efficacy in portraying late-time universe phenomena. aim is to delineate constraints two prevalent models within this framework, namely Log-square-root model and Hyperbolic tangent-power model, by employing framework of Big Bang Nucleosynthesis (BBN). approach involves elucidating deviations induced freeze-out temperature ($T_{f}$)...

Abstract: The authors considered the bulk viscous fluid in f ( R , T ) gravity within framework of Kaluza–Klein space time. coefficient ξ expressed as <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mrow> <m:mi>ξ</m:mi> <m:mo>=</m:mo> <m:msub> <m:mn>0</m:mn> </m:msub> <m:mo>+</m:mo> <m:mn>1</m:mn> <m:mfrac> <m:mover accent="true"> <m:mi>a</m:mi> <m:mo>˙</m:mo> </m:mover> </m:mfrac> <m:mn>2</m:mn> <m:mo>¨</m:mo> <m:mo>,</m:mo> </m:mrow> </m:math> $\xi = {\xi _0} + _1}{{\dot a} \over...

The late time accelerated expansion of the universe can be realized using scalar fields with given self-interacting potentials. Here, we consider a straightforward approach where three cosmic fluid mixture is assumed. fluids are standard matter perfect fluid, dark matter, and field role energy. A dynamical system analysis developed in this context. central played by equation state [Formula: see text] which determines acceleration phase models. Determining domination particular at certain...

In this work we try to understand the late time acceleration of universe by assuming some modification in geometry space and using dynamical system analysis. This technique allows behavior without analytically solving field equations. We study phase stability properties critical points which could be compared with observational results. consider an asymptotic two particular models $f(R) = R - \mu R_{c} \frac{(R/R_c)^{2n}}{(R/R_c)^{2n} + 1}$ \left[ 1 (1 R^2/R_{c}^2)^{-n} \right]$ $n,\mu, R_c...

Cosmological dynamics are investigated in detail through systematic procedures by using the autonomous system analyses of gravitational field equations $ f(Q) gravity. The explicit late-time cosmic evolutions demonstrated for fundamental three types models under presence non-relativistic matter (i.e., dark and baryons) as well radiation. stability cosmological solutions is also explored examining non-hyperbolic critical points based on center manifold theory. It shown that acceleration...

Abstract The higher-curvature gravity with boundary terms i.e the f ( Q ) theories, grounded on non-metricity as a fundamental geometric quantity, exhibit remarkable efficacy in portraying late-time universe phenomena. aim is to delineate constraints two prevalent models within this framework, namely Log-square-root model and Hyperbolic tangent-power model, by employing framework of Big Bang Nucleosynthesis (BBN). approach involves elucidating deviations induced freeze-out temperature...

We explore an autonomous system analysis of dark energy models with interactions between and cold matter in a general systematic approach to cosmological fluids. investigate two types such as local non-local ones. In particular, form interaction is directly proportional only the density, while density well Hubble parameter. As consequence, it explicitly demonstrated that both cases there exist stability points terms parameters. This work aims at obtaining acceleration using without modifying...