I recently answered a question Open Sets Boundary question and I later discovered my answer was incorrect(I edited in a proof that it was incorrect into the answer). Is it best to just leave it as it is now or delete the answer since it doesn't answer the question(though now it does suggest a solution method).
Edit it to be correct. First of all, you don't want to attract those downvoters, but much more importantly, you know the correct answer. So why not make it correct to make that answer helpful to the community?
If you know it is wrong, but if you don't have the correct proof, please either:
- Delete it
- State, in big, bold letters at the top that it is incorrect
I have one thing to add: please, if someone has since added a new, correct answer that obviates any novelty that would result from correction of your answer, please delete your answer. It's effectively like adding a copycat answer at that point.
I would like to add the perspective that as long as you are transparent and make it very clear that you are now aware of a mistake in the answer, that even a failed attempt can be beneficial to those reading the question - too often it is the case in mathematics that we only present polished, perfected proofs, and omit the failed attempts and near misses.
In such situations, I think it is not always the best option to delete the incorrect answer, but to instead edit it to explain why your reasoning is flawed, even if you are not sure how to correct the failed attempt. As others have mentioned, it should be extremely apparent that you are aware of a mistake and you have made every effort to inform the reader that the attempt is mistaken.