Today, I saw my profile page on stackexchange community showing that 'You have not participated in any tags'. I don't know why my tags and the tag badges have been removed from my profile pages on the entire community. Will these tags and tag-badges be re-awarded? Could someone explain me the rea...

Across the network, users are reporting cases where tag badges are re-awarded: Re-earned all my tag badges at once (Role-playing Games) Tag badges "re-awarded"? (Mathematics) Why were all tag badges unawarded and then awarded again? (Spanish Language) Tag badges got refreshed just for me? (Arqad...

Top [tag]s doesn't show anything for some users https://dba.stackexchange.com/users/171/jcolebrand?tab=profile This is true on several users pages on [dba.se] but the reason for it to show on some pages and not others is unclear. Thoughts?

Which parts of the Axler’s book on linear algebra are prerequisites for further topics, mainly analysis(vector,complex and fourier), measure theory, differential equations and topology, in undergrad/beginning grad pure math curriculum? Meaning the active knowledge one should have on linear algebr...

On page 18 of this paper, the author states that there is a duality (correspondence?) between semilattices (i.e., abelian semigroups of idempotents) and totally disconnected locally compact Hausdorff spaces. Given a semilattice $E$, consider the space of characters $$\widehat{E} := \{\chi : E \to...

I've got a problem related to $(p,q)$-shuffles that comes from the Eilenberg-Zilber map $\nabla$ when I tried to show that this map is associative in the sense that $\nabla(\nabla\otimes 1)=\nabla(1\otimes \nabla)$. On one side, I have for $(p,q)$-shuffles $(\mu,\nu)$ and $(p+q,r)$-shuffles $(\...

In general, $0$ is prime ideal in ring $R$ if and only if $R$ is integral domain. But in number theory, I heard 'prime ideal which is not $0$' is often called just 'prime ideal'. So,for example, the statement 'every prime ideal is maximal in PID' is considered as false in general context, but in ...