Nicholas P. Timms
Submitted: December 2025 : Publish: 16th April 2026
Abstract
The mapping of human brain development has traditionally relied on network neuroscience and graph theory, while the fundamental nature of vibrational states in disordered solids has remained the exclusive domain of condensed matter physics. This paper introduces a novel theoretical framework that synthesizes lifespan connectomics with the unified theory of phonon dynamics, proposing that the human brain operates as a physical material undergoing distinct topological phase transitions. By reframing the neural connectome through the lens of disordered media, we demonstrate that macroscopic structural and functional brain reorganizations mirror the thermodynamic shifts between highly integrated crystalline states and disordered glassy states. Specifically, we model the human lifespan as a trajectory across a phase diagram of non-Debye anomalies. Early neurodevelopment resembles a cooling liquid that progressively crystallizes into an optimal state of long-range order, maximal cognitive efficiency, and unhindered signal propagation—analogous to a Van Hove Singularity—peaking during early adulthood. Subsequent aging represents a fundamental glass transition characterized by the Boson Peak, wherein the breakdown of global neural integration and the rise of anatomical modularity produce a landscape of localized, damped vibrational modes. Ultimately, this unified theory redefines established neurodevelopmental milestones as rigorous physical phase transitions governed by continuum elasticity and disordered scattering. This paradigm suggests that age-related cognitive decline is fundamentally driven by the encroaching entropy of the neural glass transition, providing a purely physical grounding for the study of lifespan connectomics.
