Conjecture on the Schauder fixed point theorem and the degree of non-densifiability

Let CC be a nonempty closed, bounded, convex subset of a Banach space, let f:C→Cf:C\to C be continuous, and suppose that fnf^n is compact for some integer n≥1n\ge 1. Then ff has a fixed point; that is, there exists x∈Cx\in C such that f(x)=xf(x)=x.

References

Primary source

Archiv der Mathematik

Additional references

Progress summary

Refreshed
Claimed progress

A new paper proposes a connection between Schauder fixed points and non-densifiability, but its mathematical conclusions cannot yet be assessed.

The entry concerns a conjectural relationship between the Schauder fixed point theorem and a degree-like notion of non-densifiability. Gonzalo García is named as author, but the retrieved record gives no abstract or result details, so it does not show whether the conjecture was proved, disproved, or merely formulated.

Known results

For the broader Schauder conjecture, Cauty reported proofs in 2005 and 2010, but earlier arguments were challenged for gaps. A 2021 paper by Ennassik and Taoudi claimed an alternative proof, while a 2023 article reportedly identified an incorrect recent proof and supplied a counterexample to an intermediate lemma.

September 2026 paper

The newly published article formulates and investigates the proposed relationship, but the available record contains no theorem statement, proof, counterexample, or conclusion. Its contribution is therefore a claimed advance, not a verified resolution.

Current status (as of September 2026): The specific non-densifiability conjecture remains unverified; a new paper has been published, but whether it proves or refutes the conjecture is unknown.

Sources

Solutions 0

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