# Tag Info

### Requests for reopen and undelete votes for closed and deleted questions

[RE-OPENED and later CLOSED again] The question How the idea of adjoint matrix has been designed? isn't great, but isn't awful, and these two answers have been posted (and upvoted) on G+ rather than ...
Accepted

### Why was my question deleted?

Cross-posting is generally frowned upon, the post was flagged as a cross-post, and with no answer it is my general approach to simply delete the cross-post. However, in this case the post had gone ...
• 36.6k

### Reviving questions from the PROMYS application?

This is a genuinely tricky question. I incline toward agreeing with the policy that while we can try to keep problems off the site while applications are open, we can't be expected to play whack-a-...
• 42.4k

### Requests for reopen and undelete votes for closed and deleted questions

[RE-OPENED] I believe the post Can you write $\mathbb R^2$ as a disjoint union of two totally disconnected sets? has been closed (or put "on hold") erroneously, as a duplicate of Can you explicitly ...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] The question Has Perelman's proof been accepted or are there still unresolved issues? has been closed as of this writing. At first glance, this question seems to be of the genre, "Is ...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] The OP of this question Connected sum is well-defined for surfaces, proof? requests reconsideration to reopen. It was closed as a duplicate, but OP says that what is asked for was not ...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] I'd like to suggest reopening Covering systems. As I wrote in a comment, Why is this closed? Covering systems are a recognized area of research in Number Theory. It's known that in an ...

### Requests for reopen and undelete votes for closed and deleted questions

The question A question on $p$-approximation property from 2014 has been automatically deleted owing to lack of upvotes. While I can't immediately tell if it is a good question, it seems a perfectly ...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] Parameterizing rotations of a cube was asked and answered, but I don't see a reason for closing it.

### Requests for reopen and undelete votes for closed and deleted questions

[UNDELETED] This is an undelete request for an answer on meta: namely, quid's answer to my question Some proposals for modifications of the process of closing/reopening questions . The answer was ...

### Requests for reopen and undelete votes for closed and deleted questions

[RE-OPENED] I think that the question How does a mathematician choose on which problem to work? was too broad in its original formulation (beginning: "How does mathematical research work?") and so I ...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] I'd like to nominate this question. It originally got closed due to a typo, which has been fixed. It's certainly not "unclear what you are asking" any more (the original reason for closing)...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] The question Center of a monoid ring asks two questions, one of which can be found in standard texts and the other which is essentially an open question but which appears to be a harmless ...
Accepted

### Interesting question deleted by author — how to reach out to author to ask to undelete?

Thanks to @Emil Jeřábek for finding the author of the question, whom I have now e-mailed. (ETA: it's back now!) Thanks also to @Martin Sleziak for his answer in comments to the meta-question of "...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] This question was heavily downvoted and closed: When a compact topological manifold with boundary is a ball? Color me ignorant, perhaps, but I wondered if it were as trivial as the ...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] The question Lexicographic order on increasing $k$-tuples by a first-time poster was closed as "unclear what you're asking". I have rewritten it so that (I think) it is now clear. It is ...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] "Find a TSP tour passing through at least one node in each set of nodes" was initially unclear, but the author has now clarified it into a real question (and I corrected the English): Is ...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] The question Identify one group of linear transformations was closed as "unclear what you're asking". Afterwards it has been edited and clarified. I don't see what is still "unclear" in ...

### Requests for reopen and undelete votes for closed and deleted questions

[UNDELETED] [REOPENED] [CLOSED] I would suggest to undelete/reopen https://mathoverflow.net/q/328312, as a courtesy and sign of respect, and then hopefully one of our experts can answer it. I know, ...

### Requests for reopen and undelete votes for closed and deleted questions

Status: [REOPENED] Thank you! Request to reopen How to obtain the rational solution of a linear system efficiently?. In light of recent discussions about being more welcoming to good faith questions ...

### Requests for reopen and undelete votes for closed and deleted questions

https://mathoverflow.net/questions/379145/geometric-combinatorial-problem-in-the-euclidean-space This question was deleted by nobody less than @ToddTrimble just 10 days ago after having 9 upvotes and ...

### Undelete request, Question 290941

The question has now been undeleted (revisions/timeline).

### Requests for reopen and undelete votes for closed and deleted questions

[Undeleted; Reopened] If normal with respect to prime base then normal for all bases was closed as not being research math. I nominated it for reopening, after leaving a comment establishing its ...

### Requests for reopen and undelete votes for closed and deleted questions

[UNDELETED] I propose that this question should be undeleted: Reduced ring with all non-prime ideals finitely generated It was deleted by the OP despite having a substantial answer by Keith Kearnes. ...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] Why did Bourbaki ignore the theory of categories? only survived 25 hours in 2013, collecting 5 answers; it has been closed ever since. The reason given (“not constructive”, “will likely ...

### Requests for reopen and undelete votes for closed and deleted questions

[UNDELETED] I propose to undelete my question: Something like mathoverflow in other sciences It was asked in the early days of MO and has some useful links and information. I Have no idea why some ...

### Requests for reopen and undelete votes for closed and deleted questions

A chess question of W.T. Tutte has been closed for at least 5 years. The only argument given for its closure at the time was that a moderator saw it as a question of chess strategy. I think the first ...

### Requests for reopen and undelete votes for closed and deleted questions

[REOPENED] I asked in a separate thread about the closing of the question a question on 0-1 valued stochastic process, located at a question on 0-1 valued stochastic process, and it was suggested ...
[UNDELETED] The question Does there exist some $C$ independent of $n$ and $f$ such that $\|f''\|_p \geq Cn^2 \| f \|_p$, where $1 \leq p\leq \infty$? seemed decent enough and had a good ...