Abstract. In this study, we investigate the cyclic evolution of the Universe within the framework of Brans-Dicke theory (BDT) by adopting a periodic varying deceleration parameter (PVDP). The proposed model consistently captures the complete cosmic cycle--birth, expansion, slowdown, contraction, and rebirth--thus realizing a bouncing or oscillatory cosmology. The dynamical behavior of fundamental kinematic quantities, including the Hubble parameter, scale factor, and directional expansion rates, substantiates this recurrent evolution. Furthermore, cosmological parameters derived from the modified field equations--such as energy density, pressure, the cosmological constant, and the equation of state (EoS) parameter-exhibit patterns that align with the cyclic nature of the Universe. To strengthen this analysis, higher-order cosmographic parameters (jerk, snap, and lerk) are also computed and examined with respect to cosmic time, providing refined insights into the model's dynamical consistency. The interplay between these parameters reinforces the oscillatory features of the Universe and demonstrates agreement with observationally motivated phases of cosmic evolution. Overall, our findings highlight that Brans-Dicke theory, supplemented by a PVDP, offers a compelling framework for exploring cyclic cosmology beyond the standard ΛCDM paradigm.

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