The generalization of Brouwer's fixed point theorem?

2011-03-28T04:05:56Z

Let $X$ be a contractible compact [edit: locally connected] topological space (Hausdorff and second countable). Let $f\colon X\to X$ be a continuous map. Then (I suppose) $f$ has a fixed point. Personally, I cannot think of a better generalization of Brouwer's fixed point theorem, but is it true?

Answer by Daniel Litt for The generalization of Brouwer's fixed point theorem?

2011-03-28T04:34:34Z

No. I believe the first counterexample is from:

Kinoshita, S. On Some Contractible Continua without Fixed Point Property. Fund. Math. 40 (1953), 96-98

which I unfortunately can't find online. Kinoshita's example is described on page 127 in this excellent article by Bing, however.

EDIT: The question has been revised to add the local connectivity condition; as stated, I think the question is open. If "contractible" is replaced with "acyclic" there are counterexamples dating back to Borsuk, referenced e.g. here; Borsuk's paper, which I can't find online, is:

K. Borsuk, Sur un continua acyclique qui se laisse transformer topologiquement en lui-meme sans points invariants, Fund. Math. 24 (1935), pp. 51-58.

This suggests that if the OP's conjecture is true, it is unlikely to be open to homological attacks.

The generalization of Brouwer's fixed point theorem? - MathOverflow

The generalization of Brouwer's fixed point theorem?

Answer by Daniel Litt for The generalization of Brouwer's fixed point theorem?