Given a circle, we want to divide it into $n$ connected equally sized pieces. In such a way that the total length of the cutting is minimal. What can we say about the solution for each $n$. Are they unique (up to some symmetry). Do all cuttings arise from the intersection of three straight segmen...

(I'm looking for an example or two to prove the point, not a list.) Has it ever been the case that a change in the C++ standard (e.g. from 98 to 11, 11 to 14 etc.) changed the behavior of existing, well-formed, defined-behavior user code - silently? i.e. with no warning or errors when compiling w...

I'm refereeing a paper and it looks pretty good. I'm about ready to recommend it for publication. However, its main result depends crucially on some other results that are in preprints on the arxiv. Is it the referee's responsibility to verify those results too? Or should I just alert the edit...

I am currently reading Kervaire-Milnor's paper "Groups of Homotopy Spheres I", Annals of Mathematics, and I am trying to prove (or disprove) the following result. The more elementary the proof, the better. If two smooth manifolds are homeomorphic, then their stable tangent bundles (i.e. the Whit...

My domain registrar is Cloudflare and my site is hosted through A2 Hosting. My problem is that my email worked fine when A2 Hosting was my domain registrar and web host. Now, neither Thunderbird or Outlook can connect to my server. My current DNS records for email are: CNAME mail ...

I am a PhD student from India working on representations of quantum groups. I want to organize a workshop on Hopf Algebra and Quantum groups but there are only 2 or 3 specialists in India currently working on it. So I googled some professors outside India who are currently working on this field. ...

Upgraded to 20.04 today. And somehow not the document viewer is not able to open .svg files. It keeps giving this error. Previously when I was using 18.04 everything was working fine. No such errors I encountered. XML parse error: error code=201 (3) in (null):606:15: Namespace prefix xlink for hr...

I recently had a sonar rule (https://rules.sonarsource.com/java/RSPEC-4784) bring to my attention some performance issues which could be used as a denial of service against a java regex implementation. Indeed the following java test shows how slow the wrong regex can be import org.junit.Test;...

So I like to compress the videos I take to save space in my hard drive. The compressed videos are generated in a separate folder. So then I delete the original larger videos and then move the compressed ones from the destination folder to the original one. So, of course, generating the compressed...

Let $G$ be a compact connected Lie group and $T\subset G$ a maximal torus. Let $V$ be a representation of $G$ and $U=\{v\in V: tv=v\textrm{ for all }t\in T\}$. For any $g\in N(T)$ we have for all $t\in T$ and $v\in U$ that $g^{-1}tgv=v \Rightarrow t(gv)=gv$. This shows that for all $v\in U$ we ha...

I want to dual boot windows 10 and ubuntu but I can't see the option to install alongside windows 10 during ubuntu installation. Yet ubuntu installer recognizes windows 10. My pc has 4 partitions. Please help

I created an EC2 instance on AWS, and I was assigned a default "security group". I understand that this acts as a virtual firewall for my server. I had trouble ssh-ing ino this EC2 instance, and it turned out that the issue was not setting the "Source" to 0.0.0.0/0 in the security group's "Inboun...