AngelTC

Last night I saw mubi had a double feature of Ripstein's Castle of purity and Lanthimos dogtooth so I decided to watch them back to back. Before this I was not aware of Dogtooth ( but I had seen and enjoyed The Lobster ) but I had seen bits and pieces of Castle of Purity.

I am not terribly interested in getting in an argument about whether there was unattributed inspiration or whether Lanthimos owed anything to Ripstein, I have made up my mind about this but arguing either way feels like getting in a pointless debate of which there seems to be a few online already.

What I'm interested in talking about is in comparing the movies for what they tried to achieve and what did they manage to a

I was reading some paper today that were discussing in passing some really hard classification problems that seem/are to be impossible to achieve and that even when reducing to some more specific cases there are situations where there seem to be no hope for us to fully understand the subject with our current knoweldge and technologies.

So I got curious, historically is there a subject that people from 50, 70, 100, 200 years ago thought to be just impossible but where mathematicians eventually managed to make a remarkable dent?

Im particularly interested in reading the opinion of those at that time, although I imagine the way people thought about math 200 years ago was a bit different, but

I would be interested in learning about the experiences of non english native speakers when it comes with learning math.

Did you know english before/independently of studying math?

Have you been in a situation where language has been a barrier, even if small, to communicate with people?

What about resources like videos, textbooks, notes, etc? Would you have preferred if they were in your mother language?

Do you think a large(r) math community in your language would be benefitial to* you?

I understand the irony of posting this in english.

I was reading this thread on MathOverflow and I got curious about what would the responses be here ( also the MO people are very strict about their rules so.. ).

So, after over a year how has the pandemic affected you in how you study, practice or research mathematics?

While Im sure there's a lot of people who might consider the last homotopical shift in algebraic geometry to be part of the original categorical shift of Grothendieck in the 60s, I think that the fact that there is at the very least a cultural divide in mathematicians who work at the level of schemes and those who have seen a need to expand into the higher categorical realms is a good argument to say there's been two. There are of course also people who work with honest algebraic varieties, perhaps just with the compromise of using modern language but mostly caring about the more classical problems and techniques.

So, what is it with algebraic geometry? Are there other branches of math that

So I got a little bit curious about which other online math sites this community frequents and in which capacity, what are your impression about them and how do they feel to you?

Id prefer it if we could avoid talking bout this sub as I believe that would take away from most of the conversation that Id like to read about.

Do you frequent MO, Math. SE, AOPS, r/learnmath? FB groups, are you on math twitter? Public or private Discord servers, IRC, telegram? Mailing lists? Do you pigeon post with your friends to keep up with the latest on your research?

My favorite exercise to give to students when I teach linear algebra is to calculate the Jordan canonical form of the differentiation operator on the space of degree (at most) n polynomials, but a few years back some students came to me to ask me to please mix it up a little as the examples involving this operator were a bit complicated for them but the ones that werent about this operator were too easy for them ( I was just doing random matrices that I knew werent too hard, or simple stuff corresponding to transformations in space ).

So, to be precise, my question is about linear transformations between spaces that are interesting, by this I mean Im looking for transformation that show up