Geometric–Inertial Cosmology: Part II — Linear Expansion as a Purely Kinematic Description

The Geometric–Inertial Cosmology series presents a coherent reinterpretation of cosmic evolution based on geometry, inertia, and kinematics. By treating energy as a globally conserved geometric quantity, expansion as an inertial process, and observational parameters as time-dependent kinematic descriptors, the series offers a minimalist framework in which cosmic expansion is described without physical acceleration or additional dynamical components. Within this perspective, apparent cosmological tensions arise from interpretative assumptions rather than from inconsistencies in observational data, highlighting the importance of conceptual clarity alongside empirical precision. This work is Part II of the Geometric–Inertial Cosmology series. Doi of Part I is: DOI 10.5281/zenodo.18108138