Spectral Structure of Physical Propagation: Modes, structural selection, and organization of dynamics
Jonatan P. camargo
Abstract
We present a structural formulation of physical propagation in which dynamics are described by a unitary operator $\hat W=f(\hat H)$, associated with a self-adjoint structural operator $\hat H$, and by its bilocal representation $W(x,y)$. Time evolution is formulated as the iterative application of this operator, without assuming differential equations as a fundamental starting point. It is shown that the spectral decomposition of $\hat H$ induces a complete organization of the evolution into independent eigenmodes, each governed by a spectral factor $f(\lambda_n)$. From this structure, it is demonstrated that the bilocal propagation kernel is entirely reconstructed from the spectrum and the eigenvector basis of the structural operator. In the regime of translational homogeneity, it is proven that the propagation operator is diagonalizable in a basis compatible with translations, resulting in the absence of mixing between spectral modes. Outside this regime, it is shown that the support of the kernel $W(x,y)$ completely determines the connectivity of propagation, while its off-diagonal structure encodes relations between distinct nodal states. Additionally, it is established that quantities defined as functions of the structural operator can be evaluated directly in the spectral basis, providing an intrinsic characterization of the dynamics in terms of the spectrum of $\hat H$. The results obtained do not constitute a complete physical theory nor do they establish a direct identification between the operator's spectrum and specific empirical observables. The objective of this work is to make explicit the structural level at which propagation is organized by unitary operators and by their spectral decomposition, providing a coherent basis for further developments.