3:59 AM
BTW it is possible to use the usual tag syntax in chat, which makes tags clickable - [tag:tagname] or [meta-tag:tagname] .
So far there are no questions tagged . The tag was created back in February, here is link to the tag-excerpt.
> A relational structure is a set endowed with a family of relations. Occur in model theory (where these often referred as "structures" or even "models"). Also specifies to universal algebra, where each $n$-ary law can be viewed as a $(n+1)$-ary relation.

1 hour later…
5:24 AM
1

Take a $\mathcal C^2$ potential $V:\mathbb R^d\to \mathbb R$, and assume that it is bounded from below (say $\min V=0$ for simplicity, so that $V\geq 0$). Consider the autonomous gradient-flow $$\dot X_t=-\nabla V(X_t)$$ and let $\Phi(t,X_0)$ be the corresponding flow. It is well-known that if ...

6:17 AM
@MartinSleziak Sorry, indeed I meant and . I created the latter, added tag info, amended tag info for the previous one.

A new tag was created. This tag also has a tag-excerpt and a tag-info.
> An algebraic system is is a set endowed with a family of finitary relations and laws. Occurs as framework of model theory (where these often referred as "structures" or even "models"). Also specifies to universal algebra (when there is no relation). This is the same as a (finitary) relational structure with some of the $(n_i+1)$-ary relations being viewed as $n_i$-ary laws.
> This tag replaces . Algebraic systems at encyclopediaofmath.org.
6

Let $(X, {\mathrm{dist}})$ be a metric space. In the paper by Kramer, Shelah, Tent and Thomas , they define an algebraic system $A(X)$ as the set $X$ with countably many binary relations $R_\alpha$, for all positive rational $\alpha$: $(x,y)\in R_\alpha$ iff ${\mathrm{dist}}(x,y)<\alpha$. Is thi...

2

In mathematical music theory several ordered groups are considered. Some examples contain the frequency space or Tonnetzes. Other groups (commutative and non-commutative ones) are discussed by Dawid Lewin (Generalized Interval Systems and Transformations), Rudolf Wille (discussed also by Jan Thom...

I am not sure to which extent this tag is in danger of being misused. (For basically anything related to any system of some algebraic objects.) I expect that it might be used homework questions about systems of equations - but such questions get cleaned-up rather quickly.
I suppose that if somebody objects to the creation of the new tag, they will raise this on meta.

1 hour later…
7:31 AM
@MartinSleziak All four tags created in that question - , , , - are now gone.

2 hours later…
9:57 AM
@math if you make such edits could you do it completely (and in a single step)? namely putting "T(x)=2x mod 1" also in math mode, with "$\backslash$operatorname{mod}". Also it would be great if you can change your username to a more distinctive one. — YCor 52 mins ago
@MartinSleziak same remark :) — YCor 1 min ago
I think my username is quite distinctive.
@YCor I missed that mod isn't in math mode. In any case, T(x)=2x \pmod 1 is definitely better than using \operatorname{mod}. Just compare $T(x)=2x \pmod 1$ and $T(x)=2x (\operatorname{mod} 1)$.
I guess \bmod could be reasonable too, but \pmod is closed to what the OP wrote in the text version. 2x\bmod 1 $2x\bmod 1$.
To my defense, I saw that the question was bumped, so I looked whether there are other things to improve. I saw https (replaced http) and that a link to the book can be added. I did not notice the thing which you pointed out.
In any case, it would be nice to see some edits also from the MO folk. (Anybody can do the same - look whether there are some further improvements if they see that some post has been bumped.)

10:20 AM
@MartinSleziak oh great, I didn't know \pmod. No need for defense :) also of course you noticed that the username remark was addressed to the other user.
PS I erased both comments there, so there's no more recent comment on the concerned question

1 hour later…
11:22 AM
Sorry if I was unfriendly (or too defensive) in my reaction. I am kind of used to the fact that I have to defend my edits to the people from MathOverflow.
In fact, I decided to cut back on editing on MO since this post: Restriction on Number of edits. It seems that I usually manage to stay below 100 edits per month: data.stackexchange.com/mathoverflow/query/1228286/…

11:47 AM
A new tag was created. That does not sound as a reasonable name for a tag.
-3

Let $\alpha$ be a positive rational number and $\theta$ be a real number, I have tried to solve the following equation: $$(\cos {\theta})\alpha^{(1/\cos \theta)}+({1/\cos \theta})\alpha^{\cos \theta}=2 \alpha$$ in rational numbers regarding values of $\theta$, I have got only $\theta =0$ ? Are ...

The same tag was created once before - apparently by a mistake: mathoverflow.net/posts/127311/revisions

4 hours later…
3:49 PM
@MartinSleziak The question is deleted, I erased the tag.

3 hours later…
6:36 PM
A temporary comment in order to get the list of linked questions updated: Are research questions in MSC 97 (Mathematics education) allowed on MO?Martin Sleziak 1 min ago
Only now I noticed that this was a question on meta. So it won't appear in the list of linked questions.

5 hours later…
11:30 PM
0

The tag ft.factorization-theory was created in 2016 by a user who did almost the totality of the 23 questions with it. It is formatted as a top-level tag, while it isn't. Could it be changed to factorization-theory? This tag has empty tag info, seems to be concerned with the multiplicative monoi...