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4:06 PM
In psychology research literature, the term child prodigy is defined as person under the age of ten who produces meaningful output in some domain to the level of an adult expert performer. Child prodigies are rare, and in some domains, there are no child prodigies at all. Prodigiousness in childhood does not always predict adult eminence. The persons listed here have come to the haphazard attention of history or current news and probably do not represent the typical experience of a child prodigy. == Mathematics and science == === Mathematics === ==== Born 1600–1699 ==== Juan Caramuel ...
Interesting read.
Norbert Wiener (1894–1964) began graduate studies at age 14 at Harvard and was awarded PhD at 18 for a dissertation on mathematical logic
@JasperLoy this means to be a genius ^^^
Carl Friedrich Gauss (1777–1855) made his first ground-breaking mathematical discoveries while still a teenager. Also at the age of 3 watched his father add up his accounts and corrected him
 
William James Sidis (1898–1944) set a record in 1909 by becoming the youngest person to enroll at Harvard College, at the age of 11 years. He entered Harvard at age eleven and, as an adult, was claimed to be conversant in over forty languages and dialects.
Charles Fefferman (born April 18, 1949) Entered college at age eleven, later becoming the youngest full professor in the United States. He has won many major awards in mathematics, including the Fields medal.
He received his B.S. from University of Maryland in mathematics, which is part of the University of Maryland College of Computer, Mathematical, and Natural Sciences at age 17. Then received his PhD in mathematics at 20 from Princeton University under Elias Stein, Fefferman achieved a full professorship at the University of Chicago at the age of 22. This made him the youngest full professor ever appointed in the United States.
I think it's enugh to have a picture of how a genius should look like. @JasperLoy
 
Hi @Krijn
 
4:21 PM
Hey @Balarka
I saw your mention but I thought you must have mistyped someone else
 
No, I meant to ping you. Weren't you an arithmetic geometer?
 
@user1618033 Sidis also holds the record for highest IQ, although that is a controversial subject of course. He ended up as a shoe maker or something, didn't he?
I took a course on Algebraic Geometry, that hardly qualifies, does it?
 
I think it does, but IDK. Soham's asking about the analog of branched covers for maps between affine schemes.
 
@BalarkaSen Much easier than the covering argument.
 
@Krijn It seems a very controversial figure, some thinking that around him there were made many exaggerations. I also saw a documentary in the past that mentioned him, it was about the smartest people that ever lived on earth.
 
4:24 PM
But you looked it up. Does not qualify as being easier.
 
@BalarkaSen I still do not understand the post in that thread
This is a much easier variant
 
Anyway, I'm gonna cook. I'll be back here tonight I think
 
You filled in the details, but that hardly qualifies as original. I prefer the covering argument in any case.
 
According to the discussion on that thread, you need a graph theory argument to construct the chain of Lipschitz neighborhoods
 
Yes.
 
4:26 PM
that's hardly trivial
 
I didn't say it was. Just that geometrically very apparent.
I have used this kind of argument before in covering space theory, say.
 
apparent to you, I still don't get it. Something with shrinking balls, but that's hardly nice
 
You cover your compact set by balls over which $f$ becomes Lipschitz. That can be done.
 
you have to pick all of them to be the same size
 
Sure, why not.
 
4:28 PM
that's nontrivial too
 
No.
 
how does the argument go?
 
I am not going to do it for you.
 
ok, I guess I'll be left to wonder
 
If you want, sure.
 
4:30 PM
I like this argument far more, I'm not going to save the geometric proof
 
That's fine.
@0celo7 Ok, this is the Lebesgue number lemma.
 
@BalarkaSen Ah, right.
I don't have that at my disposal.
 
The Lipschitz open sets cannot be arbitrary small inside your compact set, is the point.
@0celo7 Fair enough. This argument is much less ad-hoc however: it's worth working it out. But if you don't want to, sure.
 
@BalarkaSen By "me" I mean "it hasn't been talked about in class"
 
Yes, I get you.
Not particularly an analysis fact, Lebesgue.
 
4:34 PM
anyone here with some knowledge of analysis? :p
 
@N3buchadnezzar I don't know much analysis, but you should post it.
 
@BalarkaSen Trying to understand the abstract of a paper
Just for a start, is the torus $\mathbb{T}$ defined as $\mathbb{C}/(\mathbb{Z} + \tau \mathbb{Z})$?
 
I think $\Bbb T$ means the one dimensional torus in the first snippet, aka, the circle.
 
Right, that makes sense
And in the first snippet, what do they mean by the orthogonal projection
 
If you have a closed subspace of a Hilbert space, you can always orthogonally project to that subspace with respect to the inner product on the space you have.
It just means "perpendicular projection" in the standard sense. If $W$ is a Hilbert space, $V$ a closed subspace, there is a canonical decomposition $W \cong V \oplus V^\perp$, just as in the finite dimensional case. Then you project to the first factor.
 
4:45 PM
Right, since it is closed and bounded.
 
Um, what is bounded?
Linear subspaces aren't bounded.
 
Well we are working on the circle?
 
We are working on the space of $L^2$-functions on the circle.
 
damn, @Balarka is turning into a baby analyst ... how ironic :P
 
I got you =)
 
4:47 PM
@TedShifrin Feel free to take over, I dunno much about analysis.
 
@TedShifrin I need a pat on my back =( I understand very very little. Hopefully time and hard work helps.
 
I don't know much about nothin'.
hi N3
 
@TedShifrin I disagree. Hi, by the way.
I fell a little ill today. After a long time.
 
I never learned much operator theory at all.
Damn, Balarka. Stop that!
 
4:49 PM
I havent learned any operator theory :p
 
I don't know what operator theory even is.
 
Study of linear operators on Hilbert and Banach spaces :P
Note that they're not all continuous.
 
Ah. I agree.
 
I've also never played with Dirichlet series ... too much like number theory :D
 
But Dirichlet series is what is hot these days / what all the cool kids do.
 
4:51 PM
Depends on which oven you're in.
 
lol
I like that one
 
Oh oh ... then I know it's bad.
 
Read a few German papers, unsure if they would like it as much.
 
@TedShifrin Nice fact: take a holomorphic function $f$ which grows at most like $\exp(c|z|^\rho)$. Then $\sum_{k \geq 1} 1/|z_k|^s$ is finite for all $s > \rho$, where $z_i$ are the zeroes of $f$ (assume none of them are zero).
Makes me think of Dirichlet series.
Maybe one can come up with smart holomorphic function whose zeroes appear at the points where the Dirichlet characters are zero. That $L(1, \chi)$ is finite is a big problem in number theory, I think.
 
4:56 PM
You can probably see that from the Weierstrass product formula ... I've taught some stuff like that ... but long ago.
 
Yeah.
It's actually a consequence of the Jensen's formula.
 
I've heard about him
 
an iq record beater ends as a cobbler ?
its hard to believe such kind of things happen in the us, i thought it is a third world particularity
 
5:14 PM
good evening
 
@Alessandro evening
 
@TedShifrin hey
 
 
2 hours later…
7:41 PM
hi @BalarkaSen
 
@Adeek Hey.
 
r9m
@N3buchadnezzar Hi :) How are you?
 
Meh :p
 
7:59 PM
@r9m hav u thought about some numerical getaround ?
assign a number to each arrow , that may help
 
r9m
8:18 PM
@Agawa001 no constructive ideas along that line so far :(
I was also wondering if this problem is more suited for a different SE .. say for the one for puzzles?
 
@r9m me too, but time is the only referee
yes puzzling
reduplicate it
 
r9m
I will ,, :)
 
@r9m did u try to press on the dot when u mistook it for the comma ',' it happens to me too
.. # ,,
 
r9m
@Agawa001 ya :P .. it often does
 
lol wierd, people must remap the french-keyboard (azerty)
 
user227867
8:56 PM
@Agawa001 You misspelled weird.
 
@JasperLoy can u please be less nitpicky , i dont have that far sight and im lil bit dyslexic
 
r9m
9:09 PM
@robjohn @DanielFischer any ideas here? :-)
 
user227867
@TedShifrin Maybe also more general topological vector spaces. =)
 
user227867
@N3buchadnezzar The font looks terrible. No meat, no pudding, lol.
 
@JasperLoy The content is even worse
 
user227867
@N3buchadnezzar I cannot judge the content. I am only a banana.
 
user227867
9:53 PM
@user1618033 I am beginning to see now how evil this person is, the one who scolded me today. I remember all the things he did over the years to me and the users of this site. Wow, just wow...
 
@JasperLoy You're so awesome. Why would one want to harm you in this way? I have no idea who and what did to you.
 
user227867
@user1618033 It's just stupid things, never mind. I think I should just ignore him from now and not waste my energy.
 
@JasperLoy Avoid as much as you can the negative energy.
 
user227867
@user1618033 Yes, you are right. Was the latex file you were trying to fix your book?
 
@JasperLoy yeah! :-) I had some crazy problems in there but finally things worked nicely.
The solution provided worked perfectly.
 
user227867
10:04 PM
@user1618033 Yay! =)
 
@JasperLoy It's a huge file. There is also a large part in another file that is related to some of my published stuff.
This part I add to at the end.
 
user227867
@user1618033 These are Chris's notebooks, just like Ramanujan's notebooks =P
 
@JasperLoy :-)))
@JasperLoy It sounds cool!
 
user227867
OK
 
@JasperLoy What do you usually do on Sunday?
 
user227867
10:12 PM
@user1618033 Every day for me is the same. I sort out my thoughts, watch movies, walk, sing, read the internet. But hopefully in 2017 I will be well and then I will study math full time.
 
@JasperLoy Well, I think you do well, even better than me. I usually only work like a mad one.
 
user227867
@user1618033 No, one cannot do well when he is mentally ill, like me. I can't even go to work and earn a living.
 
@JasperLoy Well, I don't perceive you ill at all. But I consider your words.
Hope you get well then.
 
user227867
@user1618033 Hehe. Again, I hope you will be able to become a professional mathematician.
 
@JasperLoy I can only say that time has revealed great suprises to me. If this continues like that, who knows what will be next. :-)
I'm out to take some sleep.
 
r9m
10:23 PM
@user1618033 @JasperLoy if you like puzzley stuff you can check this out in your free time :-) I'm pretty much stumped ..
 
@Jasper: Of course, I was not intending that my answer be complete. Frechet spaces show up importantly, as well.
 
@r9m hav u seen skill around ?
 
r9m
@Agawa001 what is that?
 
skill patrol
 
r9m
ah .. well I haven't visited the chat in a week or so .. but I think I saw him last week or b4 that perhaps
 
10:39 PM
@Ted Heyo
@TedShifrin So I did try what you said---pushing on through the book at a higher rate with less depth.
It's pretty terrifying :D
 
r9m
10:57 PM
@DanielFischer Awesome answer!!!! :D :D Million thanks!!
I was literally screaming while I was reading $s_1$ .. magnificent!!
 
@Danu: You paged me to tell me you're terrified? :)
 
@TedShifrin Pretty much.
 
hi @r9m
 
Also to ask how screwed I am if I'm struggling with the algebra at page 20 already.
 
What kind of algebra?
 
11:02 PM
Commutative
 
Be more specific.
But, honestly, I do not know the book, so I can't comment. It's not supposed to be an algebraic geometry book.
 
For instance, the discussion of the Nullstellensatz.
"From commutative algebra, one knows that $\sqrt I$ is the intersection of all prime ideals $\mathfrak p$ containing $I$"
"the induced ring homomorphism is a finite integral ring extension"
$\text{wat}^\text{wat}$
 
OK, this is standard commutative algebra. But it is not what I think of as being in an analytic geometry course.
 
I don't know any commutative algebra beyond definitions
I figured out today that a non-trivial ideal cannot contain any units (I did not know that, though it's not hard to prove), to give you an example of the "depth" of my knowledge :P
 
Oops. That's day 1 of ring theory.
You definitely will need to fill in "undergraduate" algebra at some point, for sure. And probably take a graduate algebra course.
 
11:07 PM
I know basic stuff about groups and vector spaces, I think. But not really anything about rings.
 
He says he assumes basics on one complex variable and manifolds. Doesn't mention commutative algebra.
 
I just know some definitions, like I said. Plus the really easy things are not too bad to figure out on the spot.
@TedShifrin Well, then he's lying :P
 
I found a copy of the book on-line (without much effort), so I'm looking.
 
He just references Atiyah & McDonald
Page 19-20 is where it starts getting a bit yikes for me
 
So he does Weierstrass preparation. So do Griffiths/Harris. This is important for local structure of analytic varieties. But you can take stuff for granted.
I vote that you refer to this stuff as needed later, and go on to section 2 of chapter 1, for sure.
 
11:10 PM
Hehe
 
You will need to apply these results, but you obviously aren't going to fill in a year of algebra now, so don't stress over that.
 
Sweep sweep sweep under da rug
 
@Danu I recall you reading Vinberg...
 
I wanted to take algebraic geometry 1 (it covers a lot of basic commutative algebra, or at least did so last year) but it clashes :\
 
Well, eventually, if you want to do a Ph.D. in math, you'll need to learn more stuff. But I've taught a lot of complex geometry to people without using this particular material in any depth.
 
11:11 PM
@0celo7 Not all of it
 
Oh, clashes (conflicts) with what?
 
@TedShifrin How much algebra does, say, a geometric analyst need
 
But you need more background in rings and modules at a lower level, probably, before you take commutative algebra.
 
The course that my supervisor is teaching (Math. Gauge Theory 2/Seiberg-Witten Theory)
 
Depends on what she's working on, 0celo. I can't answer such vague general questions.
Oh, that sucks, @Danu. Any chance they could reschedule one of them?
 
11:12 PM
@TedShifrin I've got a vague recollection of the beginnings of Vinberg's chapter on rings so I think I can cope with starting at the level of Atiyah & MacDonald
 
@TedShifrin curvature flow
 
Anyhow, I stand by my advice. Be prepared to use the results, but keep moving.
 
@TedShifrin I emailed both professors, both said nope.jpg. One told me "algebraic geometry is not important for people in your program anyways" lol.
They give zero fucks
 
Oh great, @Danu. That's like how our star algebraic geometer once told his Ph.D. students that my graduate differential geometry class was wasting their time (he didn't like my assigning homework).
 
I think the main reason the one didn't want to move it is because he "did it like this for the past 10 years"
@TedShifrin Oh, great.
 
11:14 PM
They stayed in anyhow, by their choice, @Danu. Probably cuz I was a horrible teacher :)
 
Algebraic geometers are peculiar (the guy I'm referencing is also our department's star algebraic geometer, Dr. Morel)
 
Same thing happened with a number theory Ph.D. student years ago.
0celo, commutative algebra shows up all over mathematics in some form. But it is not a key ingredient in curvature flow.
Lots of PDE analysis material is, and sometimes commutative algebra shows up there, actually.
My adviser, Chern, once told me that one cannot hope to learn all of mathematics beforehand. That one should start doing research as soon as possible and then learn what's needed as one goes along.
I don't say I agree with that 100% completely, but he was a star mathematician of the 20th century, so one should probably listen to him.
Anyhow, @Danu, I always learned math by going back and forth. It's very hard to learn everything in depth in a linear fashion.
 
@TedShifrin Physicist's spirit :P
 
And some things one doesn't learn in depth. There's just too much math to know.
 
@TedShifrin Yeah, I'm also fine with skipping over algebra for now.
I'm just afraid I'll never have time to catch up :P
 
11:17 PM
Complex geometry has its own bits of (linear, multilinear) algebra to worry about.
 
That's the next section!
 
@Danu: Don't be afraid. Just keep learning and working and you'll be amazed to look back in a few years.
Yes, I know it is.
And keeping track of powers of $i$ is a pain in the ass. Lots of books get it wrong in places. :P
 
Yay :P
 
However, Huybrechts does something that bugs me dearly. He uses $i$ as an index when he also has $i =\sqrt{-1}$ flying around everywhere. I always avoided doing that.
Seriously: $x^i+iy^i =$ ... Ugh.
 
I typeset my imaginary unit as $\mathrm i$
 
11:19 PM
@TedShifrin He says "confusion does not arise" :P
@0celo7 Yuck
 
I only bold vectors.
And that only in low-level texts.
 
@TedShifrin Nothing is bolded?
 
I have trouble writing bold on the blackboard.
 
r9m
@TedShifrin Hello Professor!! :)
 
$\mathrm i$ is not $\mathbf i$
 
11:21 PM
If I'd ever deviate from $i$, the only other reasonable option would be $\imath$ imo.
 
Oh, roman, not bold roman. Hmm, well there are also the LaTeXites who insist that we need to write $\text{d}x$ in differential forms and integrals. I don't do that.
 
@Danu I take it you dislike $\mathrm e$ too?
 
The curlyness is essential
@TedShifrin You don't?
 
r9m
what does $\iota$ do I wonder .. aha works!
 
$\iota$ is used for involutions, @Danu. Scrap that.
 
11:22 PM
@0celo7 We talked about that and yes, it's terrible
 
@TedShifrin I agree with the upright there too.
 
@r9m Inclusions
@TedShifrin It's not $\iota$, though. $\imath$ is curly.
 
Well, I don't do any of this. ... @Danu: Get back to studying (or sleeping). Enough of this nonsense.
 
@TedShifrin hehe
 
wait
$\iota$ and $\imath$ are the same
 
11:22 PM
Math is hard enough without creating notational difficulties.
 
@0celo7 No. Look at the curls.
 
r9m
@Danu I see .. I am clearly missing context here .. sorry .. hehe :)
 
They don't look curly to me, @Danu.
 
@TedShifrin Do you happen to play chess?
 
11:23 PM
@Danu they look the same to me...
 
@0celo7 lolwat
Dafuq
 
I am terrible at chess, Danu. I stick to bridge (although I played that horribly the other day).
 
let's open up TeX
 
Internet, how does it work.
@0celo7 Oh, they're different, trust me.
@TedShifrin That's a shame. I love chess.
 
11:24 PM
To me, chess was too much like math work.
 
@Danu Yeah.
I knew that.
 
OK ... one of those is \iota and one of those is \i, right?
 
@TedShifrin But it's not though!
 
MathJax confused me
 
@TedShifrin No, \imath.
 
11:24 PM
oh, ok.
 
(which is why it's an obvious alternative for $i$)
 
Anyhow, a reader shouldn't need a magnifying glass to know what's going on. I complained about something like this in the typesetting of a book I reviewed for SIAM a few months ago.
 
@TedShifrin Good point. So errybody should stick to $i$.
 
exactly, so just use $\mathrm i$ and move on
 
And $k$ for labels, or $j$
 
11:25 PM
I'm moving on. Night, @Danu. Bye, others.
 
bye
 
@TedShifrin Byebye!
 
@r9m just back. I see Daniel has already answered.
@r9m I just spent an inordinate amount of time transcribing an old answer from sci.math into $\LaTeX$ to post here.
 
r9m
11:46 PM
@robjohn (+1) Holy :o That's one long answer .. will take me a lot of time to read (y)
wow! I had no idea there's an algorithm for that .. (well there should be intuitively speaking ,, but never saw a well written out one like that!!)
@robjohn in the mean time I've been working on series manipulation proofs of Euler sums (especially those of weight $6$ .. with no or very less luck for higher weights though :( .. )
 
@r9m is that similar to the ones that were done a couple of years ago?
 
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