Work

A Direct Polynomial Approach to Spectral Decomposition

Year: 2026
Type: preprint
Abstract: We give a direct construction of the spectral projectors of a complex square matrix, based on explicit interpolation polynomials previously introduced. This yields a spectral resolution $A=\sum_{i=1}^r(λ_iP_i+N_i)$ from which the Primary Decomposition Theorem, the Cayley--Hamilton theorem, criteria for diagonalizability, and the spectral theorem for normal matrices are proved by short formal arguments. A weaker form of the construction, extends to any perfect fields via a Galois invariance argument and produces the Jordan--Chevalley decomposition.
Language: English
Open Access status: green
OpenAlex ID: W7170178514
Cites: 1
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Related to: 10