A Structure-Correlation Approach to Cosmological Expansion and the Hubble Tension

This is an updated and extended version of a phenomenological model of cosmological expansion. The model proposes that the Hubble parameter depends not only on local matter density fluctuations but also on their spatial correlations. A structure-correlation framework is introduced in which both local variance and non-local coupled fluctuations contribute to observable quantities. An illustrative numerical example demonstrates the emergence of a correlation between structure and expansion, consistent with the model predictions. The framework provides a testable mechanism linking large-scale structure and cosmological expansion, offering a possible perspective on the Hubble tension.