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Mismached functions in page 133 theorem 4.2.3

Open wgbusch opened this issue 3 years ago • 1 comments

I think there is a typo in page 133, theorem 4.2.3.

"Proof. Suppose that (g, eta, epsilon) is a quasi-inverse for f ."

In the definition of qinv, the first coordinate corresponds to an homotopy between fg and Id. In the theorem it is called eta. But in the definition of ishae (page 132), eta is taken to be an homotopy between gf and Id. I think that this mismatch would be fixed simply by changing the first sentence of the proof to be "suppose that (g, epsilon, eta) is a quasi-inverse...", to match the definitions of eta and epsilon

Untitled .

wgbusch avatar Aug 05 '21 00:08 wgbusch

Hmm, you seem to be right. Would you like to submit a pull request?

I think there is a similar mismatch between Definition 4.3.1 and equation (2.4.10).

mikeshulman avatar Aug 09 '21 17:08 mikeshulman