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Surjectivity of the Gelfand map in the general setting

Establish surjectivity of the Gelfand map I_F: A → C(Max(A), F) for every topological field F and every F-algebra A in the category A_F defined by properties (Gelfand, compact spectrum of each element, and the pm-ring property that every prime ideal lies in a unique maximal ideal), thereby upgrading the adjunction between compact F-Tychonoff spaces and A_F to a duality.

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Background

The paper constructs a dual adjunction between the category of compact F-Tychonoff spaces and the category A_F of F-algebras that satisfy key structural properties (Gelfand, compact spectra, pm-ring). In special cases—disconnected complete fields (generalizing Van der Put) and complete fields satisfying Stone–Weierstrass—the authors prove that the Gelfand map is surjective, yielding a duality.

Beyond these special cases, the adjunction’s upgrade to a full duality hinges entirely on the surjectivity of the Gelfand map I_F. The authors note that this surjectivity remains unresolved in the general setting, making it the primary barrier to a complete, field-agnostic duality.

References

Notice that the only thing separating the (dual) adjunction from the duality is the Gelfand map. The surjectivity of I_F, in the general case, is an open problem.

Totally Disconnected (non-metric) Gelfand Duality (2508.11188 - Rodríguez et al., 15 Aug 2025) in Section 3 (General Gelfand Adjunction), final paragraphs