Spectral Theory of Almost Periodic Banach--Malcev Algebras and Applications to Moufang Dynamics
Marwa Ennaceur
TL;DR
This work extends Bohr’s almost periodicity to non‑associative Banach–Malcev algebras by using the relative compactness of adjoint orbits, yielding the spectral constraint $\sigma(ad(x))\subset i\mathbb{R}$ and a continuous functional calculus. It develops a rigorous framework for almost periodic Malcev algebras, introduces the intrinsic non‑associative defect $S(x,y)$, and analyzes how this defect governs non‑Lie corrections in dynamics via structural actions, with a concrete octonionic example on $S^7$. The paper then constructs a dynamical picture on Moufang loops, proves spectral properties for the Malcev Laplacian, and provides explicit results for octonionic dynamics, including strictly periodic flows on $S^7$ and finite‑dimensional eigenspace representations. The results establish a mathematically solid foundation for almost periodicity beyond Lie theory, enabling spectral analysis and dynamical studies on Malcev manifolds, with potential but speculative connections to non‑associative gauge models. Overall, the work broadens harmonic analysis and spectral geometry into the non‑associative realm, notably through the canonical octonionic example and its Malcev Laplacian spectrum.
Abstract
We introduce almost periodic Banach--Malcev algebras as a non-associative extension of Bohr's classical theory. Our framework is based on the relative compactness of adjoint orbits $\{e^{t\,\mathrm{ad}(x)}(y)\}$, which yields the spectral characterization $σ(\mathrm{ad}(x)) \subseteq i\mathbb{R}$, uniform boundedness of orbit closures in the strong operator topology, and a continuous functional calculus for almost periodic derivations. Compact Malcev algebras -- most notably the imaginary octonions $\mathrm{Im}(\mathbb{O})$ -- provide canonical finite-dimensional examples, and their associated Moufang loops carry strictly periodic flows. We also analyze structural actions on eigenspaces of the Malcev Laplacian as a concrete case study, where the bounded defect operator $S(x,y) \in \mathcal{B}(M)$ quantifies the non-associative correction. While speculative links to non-associative gauge theory are noted, they lie beyond the established mathematical scope. The recent convergence control of the BCH series for special Banach--Malcev algebras \cite{Athmouni2025} provides analytic justification for the local Moufang structure used throughout.
