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The cosmological model executing hybrid expansion law (HEL) of scale factor in Randall–Sundrum type II (RS) braneworld gravity with Gauss–Bonnet terms in the presence of bulk viscosity described by Eckart theory, Truncated Israel–Stewart (TIS) theory, Full Israel–Stewart (FIS) theory and nonlinear Israel–Stewart (nIS) theory is studied. In the hybrid expansion law, the scale factor of the universe is described by the product of power-law and exponential expansions. In the HEL model, the early inflation and its transition from deceleration phase to present accelerated phase of expansion can be explored. The constraints of hybrid expansion law model parameters are determined using the recent observational data. Thereafter, the estimated parameters are considered to explore the present value of deceleration parameter, jerk parameter and transition epoch from early deceleration to the present accelerating phase. [ABSTRACT FROM AUTHOR]

The illustration of cosmic acceleration is being presented in the framework of DGP braneworld and dynamical Chern–Simons modified gravity in the presence of casual Israel–Stewart formalism. In this way, we discuss the evolution parameter which leads to the accelerated expansion of the universe in the phantom as well as quintessence region for both gravities. The squared speed of sound ( v s 2) leads to the stable behavior of the current physical system in both gravities in the later epoch. Also, the entropy variation, as well as thermal equilibrium condition, remains valid in both frameworks at the present and later epoch. [ABSTRACT FROM AUTHOR]