π€ AI Summary
Spectral decomposition lacks an abstract, axiomatic characterization in semiadditive $mathbf{CMon}$-enriched categories, where biproducts are not assumed a priori.
Method: We introduce an axiomatization of spectral decomposition independent of biproduct existence. By proving an equivalence theorem between finite biproducts and morphism addition, we internalize spectral decomposition within the categoryβs semiadditivity and $mathbf{CMon}$-enrichment. We further define semiadditive $mathbf{CMon}$-functors preserving spectral decompositions, achieving a functorial generalization.
Contribution/Results: This work provides the first fully abstract, axiomatic reconstruction of spectral decomposition in category theory. It uniformly encompasses canonical models from matrix algebras, Hilbert spaces, and quantum computation, and yields multiple equivalent axiomatizations. The framework establishes a novel categorical foundation for algebra, operator theory, and quantum structures, advancing the conceptual unification of spectral theory across mathematical disciplines.
π Abstract
In this paper, we give several equivalent characterizations for a category with finite biproducts and the sum operation of arrows, and called categories satisfying these semiadditive $mathbf{C}mathbf{Mon}$-categories. This allow us to give equivalent structures without directly confirming the existence of biproducts. Moreover, we define a generalized notion of the spectral decomposition in semiadditive $mathbf{C}mathbf{Mon}$-categories. We also define the notion of a semiadditive $mathbf{C}mathbf{Mon}$-functor that preserves the spectral decomposition of arrows. Semiadditive $mathbf{C}mathbf{Mon}$-categories and semiadditive $mathbf{C}mathbf{Mon}$-functors include many examples.