Mathematics - 2014-12-23 (page 9 of 10)

@N3buchadnezzar Hehe. My music teacher had a mug that said "Kiss my organ". With a picture of an organ. Too bad I have a halo and I still don't get it ;)

N3buchadnezzar

@TedShifrin Yeah, that is the correct way to vote. However I do not think everyone thinks ythe way you do. To me it seems people just gloss over the candidates and think "oh he has such points, he must be so great".

Jasper Loy

I think ultimately, my enemy did not do anything to seriously hurt me, so I should forgive and forget.

Alizter

10:08 PM

You've been around for 7 months and you have flagged 5 things. Nope.

N3buchadnezzar

@Alizter Playing in a Catholic church will get rid of that halo pretty quickly. I hear they play loads of organs there

Ted Shifrin

I don't spend my life flagging ...

Alizter

@N3buchadnezzar I think it is protestant

you know being England and all

Alexander Gruber

@TedShifrin does that mean I don't ever have to be an administrator?

Jasper Loy

I have 104 helpful flags, lol.

Alizter

10:08 PM

I don't really know

skullpatrol

OMG There is $\Huge 37$ people in here :O

Mike Miller

I guess it's time to go watch a movie and then learn the Hodge theorem, @Ted

Alizter

I am just helping the community so I can continue to use the pipe organ

Jasper Loy

@skullpatrol 37 is a special number to me.

Ted Shifrin

It's rare that one has to be, @Alex ... Usually the ones who want to be are power-hungry and therefore terrible.

skullpatrol

10:09 PM

prime?

Alizter

I finally watched Frozen the other day

Ted Shifrin

@Mike: This may be of interest to you, although you'll tell me it's trivial :P

Alizter

Let it go

Jasper Loy

@skullpatrol It's the number of strokes in my Chinese name, which I shall keep a secret.

Ted Shifrin

Way to go, @Alizter :)

Alexander Gruber

10:10 PM

@TedShifrin What if I'm power-hungrily pursuing the ability to be non-terrible? Like Batman?

Ted Shifrin

@Kaj: I gave Mark and Dan my favorite physics problem ...

Mike Miller

That was on my qual @Ted

Alexander Gruber

The Dean the University Needs, not the one it Wants

Alizter

I also watched the Mockingjay

Ted Shifrin

Oh, very cool, @Mike :)

Alizter

10:10 PM

no idea

what that was about

quid

@AlexanderGruber then you become a mod!

Ted Shifrin

I first learned it reading one of my favorite math papers ever.

N3buchadnezzar

@AlexanderGruber Deanied

Alexander Gruber

@quid ahhhh you got me

Alizter

Interstellar made the most sense

Ted Shifrin

10:10 PM

I smite you, @Alex :P

Mike Miller

Which means it's super trivial @Ted

skullpatrol

Hi @snailboat

Alexander Gruber

@N3buchadnezzar Your diploma has been placed in Timed Suspension.

Ted Shifrin

What, my learning it in Griffiths's paper, or your having it on a qual, @Mike?

Huy

@Alizter: Did you watch the other two parts of the Hunger Games too?

Kaj Hansen

10:11 PM

@TedShifrin, which one is that? Object falling off the side of a sphere, or the ladder sliding down a wall, or figuring out which direction the bicycle is travelling, or why one of the axes of rotation of a rectangular prism is unstable?

Alizter

@TedShifrin When my photoshop skills improve can I make you shoot lightning from your hands?

N3buchadnezzar

@AlexanderGruber ? :p

Alizter

@Huy I missed catching fire

Mike Miller

Anything on my quals must have been trivial, @Ted, or else I wouldn't have passed

Alizter

oops

quid

10:11 PM

How can one change the size of hats?

Ted Shifrin

The first two, coupled, @Kaj :P Are you poking fun at me? GRR.

Shaddup @Mike

Huy

@Alizter: Why would you watch Mockingjay then?

Mike Miller

I haven't watched any of the hunger games. Will I enjoy the last one?

Alexander Gruber

ohhh mod joke that may have been a bit esoteric

Huy

@MikeMiller: The first two ones are enjoyable.

Kaj Hansen

10:12 PM

Nope! I just know there are lots of problems you enjoy @Ted

Alizter

@Huy Because cinema -> Social activity

Khallil Benyattou

Dec 15 at 11:25, by Khallil Benyattou

Jasper Loy

@ali How is your cold now?

Alizter

@JasperLoy Much better thanks :)

Ted Shifrin

There were some very angry/insulting people in my class, @Kaj, not that I'm surprised.

Alizter

10:12 PM

I feel young again

wait

Mike Miller

@Huy Yes, but I'm not watching those. I'm being called upon to watch the new one.

Jasper Loy

@Alizter No problem, just pay me 100 dollars, lol.

Ted Shifrin

BTW, @Kaj, you never told me how analysis turned out. I take it I shouldn't ask?

Huy

@Alizter: I was invited to watch Catching Fire but I hadn't seen the first one yet. So I watched it at home and then could proceed to going to the cinema.

Mike Miller

Compared to me and Ted, @Alizter, you were never old.

Huy

10:13 PM

@MikeMiller: See my previous message.

Jasper Loy

@MikeMiller I feel really old in this room.

Ted Shifrin

@Mike, you're barely older than Balarka. Why do you keep aligning yourself with my decrepitude?

Mike Miller

@Huy Yes, but I only learned I'm going about five minutes ago.

Ted Shifrin

glares @Jasper

Huy

@MikeMiller: And when? Tonight?

Mike Miller

10:13 PM

@Ted Because it brings a smile to my face.

Alizter

@Huy My friend explained it to me so now I can't be asked to watch it. I get the general gist. Reminds me of avatar.

Kaj Hansen

It wasn't terrible @TedShifrin. Not optimal, but not terrible. And are you referring to your probability students?

Anonymous

@skullpatrol Hi :-) Don't mind me, I just joined because of that flag earlier.

Ted Shifrin

Yes, @Kaj, and I'm glad it wasn't terrible.

Huy

@Alizter: Sorry, I haven't watched Avatar.

Jasper Loy

10:14 PM

@TedShifrin At my age, I already should be an assistant prof. It's sad the way things turned out.

Mike Miller

No, I'm probably leaving within 15 minutes @Huy

Alizter

@MikeMiller I can't wait for my Lie in two days

Ted Shifrin

I concur completely, @Jasper.

Kaj Hansen

Lots of emails after grades were posted @Ted ?

skullpatrol

@snailboat Ok, nice to see you here :-)

Huy

10:14 PM

@MikeMiller: I don't understand. Why are you saying "no" if you're leaving within 15 minutes?

quid

@KhallilBenyattou thanks! I am not sure why I failed to figure that out myself.

Ted Shifrin

One, from a student I told probably shouldn't think about math grad school, applied or not. This person was not pleased and questioned grades. Also trounced me on evals, for sure. Not that I blame that person for getting revenge.

Mike Miller

@Huy I took tonight to mean "later tonight" instead of "immediately".

Alizter

Oh. I forgot to think about @Ted's problem

Ted Shifrin

You always forget about me, @Alizter.

Alizter

10:15 PM

I'll do it on christmas.

Huy

@MikeMiller: SPOILER: Dumbledore dies.

Mike Miller

Grades are still not up for my students. I'm going to start a riot.

That's fine, @Huy. He's entitled to.

Ted Shifrin

I'm sure the students already have, @Mike.

Alizter

@MikeMiller Make the test easier :P

Khallil Benyattou

Not a problem, @quid. It took me ages as well! ^_^

Jasper Loy

10:15 PM

@TedShifrin I think I was too kind on my evaluation of certain instructors in my undergrad days.

Kaj Hansen

@TedShifrin, can you ever tell who wrote your evals based on writing style?

Ted Shifrin

Enjoy your Christmas, @Alizter, seriously.

Mike Miller

@Alizter Grades are all in the system, but for some reason not finalized. That's why I'm confused.

Huy

@MikeMiller: I think I'd find it rather hard to enjoy the Mockingjay movie not having watched the first two. But maybe you'll like it and then the first two will become even better. Kind of what happened with me watching HIMYM and Friends afterwards.

Mike Miller

I guess maybe the professor is determining the curve?

Ted Shifrin

10:16 PM

Generally, @Jasper, I've found that students are more appreciative of me as time passes, not less.

Alizter

@TedShifrin I will. I am looking forward to new things to learn.

Ted Shifrin

Sometimes, @Kaj, but not when it's just straight 1's across the numerics.

Mike Miller

@Alizter Don't be like me, spend some time with fa-mi-ly.

Ted Shifrin

@Mike: Does UCLA not have a deadline for submitting grades? Ours was yesterday at 5 PM.

Jasper Loy

@TedShifrin I have never taken a lecture from you, so I don't know how you teach. But sometimes, you are a little grumpy in this chat. =)

Mike Miller

10:17 PM

It's the 29th, @Ted. Which is absolutely stupid.

Ted Shifrin

@Jasper: Some people in this chat make me grumpy.

Alexander Gruber

@JasperLoy I try to leave as much constructive criticism as possible even when I like the prof. (I usually preface doing so with that sentence, too.)

Ted Shifrin

And, @Jasper, being here is not my job.

Alizter

@MikeMiller I can play lego star wars with my sister all day then read lies all night

Mike Miller

I can lie to you during the day too, if you want

Jasper Loy

10:17 PM

@TedShifrin It will be your full time retirement job, lol.

Ted Shifrin

Wow @Mike for the 29th. The students are going nuts.

Alexander Gruber

I always appreciate hearing how I come off from the students. I never really know if I'm right or they're sucking up until the assessment.

Mike Miller

For instance: I am actually Ted's alt account.

Jasper Loy

@Alizter How old is your sis?

N3buchadnezzar

@TedShifrin Sorry =(

Alizter

10:18 PM

@TedShifrin Not to mention the pay here is terrible.

Ted Shifrin

No, @Jasper, it will not. I will become a full-time alcoholic. :D

Alizter

@JasperLoy 9

Mike Miller

@Ted I'm sure they are, but it's worse for me!

Jasper Loy

@AlexanderGruber By the way, did you ask for analysis book recommendation? You can try Folland, Rudin or Royden, the standard three.

Ted Shifrin

No, @Mike, in the light of day, it's not worse for you.

Mike Miller

10:19 PM

Shh.

Alexander Gruber

@JasperLoy I heard about folland and royden from Ted, haven't tried yet. Rudin is what I've got and wish I didn't

Jasper Loy

@Alizter It's nice to have a sibling to care for and to care for you, I have none.

Ted Shifrin

I don't think Rudin has been a standard ever, @Jasper. I named Folland and Royden. The new standard is Stein/Shakarchi.

Alizter

Apparently back lights on E-readers are damaging to the eyes

N3buchadnezzar

@AlexanderGruber Have you tried McDonalds?

Alexander Gruber

10:19 PM

@N3buchadnezzar No how is it?

Jasper Loy

@AlexanderGruber What's wrong with Rudin?

Mike Miller

Really, @Ted? They're wordier than even Lee or Hatcher.

Alizter

I prefer Politins books

N3buchadnezzar

@AlexanderGruber I like it. It is much less terse than rudin. Some say it is a bit wordy, but I reallt liked it.

Ted Shifrin

Lee is very wordy. Hatcher is not. You're nuts.

Jasper Loy

10:20 PM

@TedShifrin I see. the Stein books are very exotic. They omit some stuff but has other stuff.

teadawg1337

I don't recall this room being this active since I registered here...

Mike Miller

I like how wordy Hatcher is. I have heard many complaints that he doesn't shut the hell up.

Alexander Gruber

@JasperLoy I just really dislike what he decides to make theorems and what he chooses to make exercises, and the examples he chooses

Jasper Loy

@teadawg1337 Maybe it's Xmas.

Alizter

@teadawg1337 dances it's christmas

Alexander Gruber

10:20 PM

I don't like his dense writing style either

And I don't like his proofs

Or the typeface

Ted Shifrin

Well, @Jasper, that's true of most books. I used Stein/Shakarchi for complex analysis the last time and was dismayed that the multivalued nature of log was only emphasized in the last third of the book. So I vowed never to use the book again, but it was a vacuous vow.

Jasper Loy

@AlexanderGruber I see. I will be studying his 3 textbooks.

Alexander Gruber

Also I hate analysis that probably has something to do with it

N3buchadnezzar

@AlexanderGruber McDonald

Ted Shifrin

@Alex, I tend to agree with you. It's way too slick, all the time.

Alizter

10:21 PM

@TedShifrin That Lie algebra book you showed me needs somebody to typeface it nicely

Ted Shifrin

Lie algebra book, @Alizter? You mean Matrix Groups? It is old style. Done way before LaTeX.

Mike Miller

@Alizter There's quite a lot of incredible mathematics in books so old that someone had their secretary manually write in their $\mathscr U$'s.

Alexander Gruber

@TedShifrin The level of detail he puts in his proofs is really uncomfortable for me.

Jorge Fernández

@AlexanderGruber something weird happened

Ted Shifrin

You mean lack thereof, @Alex?

N3buchadnezzar

10:22 PM

@AlexanderGruber Too short?

Mike Miller

I have a book across the table from me that's so old and so many people have read that it's barely still alive.

Jasper Loy

@AlexanderGruber If you get Royden, make sure it is the latest edition, cowritten with Fitzpatrick.

Ted Shifrin

Older than me, @Mike?

Alizter

It's still better than tabbing in word

N3buchadnezzar

@MikeMiller The bible?

Mike Miller

10:22 PM

Not quite, @Ted

Alexander Gruber

I feel like he should either include much more, i.e. as rigorous as you'd expect of a student's proof, or he should just go full on Serre and include only the main idea in near-Haiku format.

Ted Shifrin

LOL

N3buchadnezzar

@AlexanderGruber Rudin is great as a reference.

Mike Miller

I did once hold a book older than you. It was a copy of some lecture notes from 1911 - written entirely by hand.

Ted Shifrin

Interestingly, @Alex, many students find that my books are too telegraphic, but I think they're far from it. They're just not calculus-book hand-holding style from cover to cover.

Alizter

10:23 PM

@MikeMiller Everybody had neat handwriting in those days right?

Ted Shifrin

By a monk, @Mike?

Mike Miller

I needed it for my number theory project at Penn State and George Andrews let me borrow it. To keep it safe, I carried it around in a shoebox (rather than my backpack).

Alexander Gruber

@TedShifrin It just depends on where the detail is omitted

Ted Shifrin

Ah, good ol' George Andrews. He once invited me to come give a lecture, and I was busy and turned him down. That was dumb.

Mike Miller

He's an impossibly pleasant human being.

Ted Shifrin

10:24 PM

I support you to whatever extent I can in this vagueness, @Alex.

Jorge Fernández

@AlexanderGruber she changed her name to Drew Cyrus

Ted Shifrin

No argument, @Mike, although I think I've only met him once.

Mike Miller

Do you know (of?) John Roe?

Jorge Fernández

Do you think it was just a feud to get a quick answer?

Ted Shifrin

Noe @Mike

Jorge Fernández

10:24 PM

reuse*

Mike Miller

Ah, shame. He's a noncommutative geometry bloke; taught the topology course there.

Ted Shifrin

bloke? So you're both Southern and Brit?

Jorge Fernández

It seems like it may be more effective than bounties

Mike Miller

Learned about fundamental groups, Fredholm Operators, Toeplitz operators, and a baby version of the index theorem.

Ted Shifrin

yes, I remember your telling me about the course when you were in it

I know his name, but I've never met him or read his work.

Alexander Gruber

10:25 PM

@TedShifrin I think it's kind of like giving Hints on MSE. If somebody presents only the main idea of the proof, the crucial step, and nothing else, I'm ok with that. It's low detail but it puts the spotlight on the part that matters. I just don't like it when somebody includes a ton of detail on peripheral stuff and then glosses over the central point of the proof

Mike Miller

I don't think I was 100% happy with it at the time, but post ipso facto I'm very glad took it.

Alexander Gruber

which is 90% of what Rudin does... it feels really lazy to me, like he's not omitting detail for pedagogy, but for laziness.

Ted Shifrin

Well, @Alex, that's one thing I've tried to teach my students — both undergrad and grad — by grading homeworks. Many have started out belaboring the obvious and leaving out what was hard. I nailed them for it.

Jasper Loy

Can someone here tell me what integral geometry is?

Studentmath

Hah. Hilbert's cube is homeomorphic to a subspace of $l_2$?

Ted Shifrin

10:26 PM

I don't think that's quite fair to lob at Rudin, though. @Alex ...

Alexander Gruber

@TedShifrin Good, that is good practice

Ted Shifrin

Yes, @Jasper, that was my thesis. What do you want to know?

Alexander Gruber

@TedShifrin No? I don't know, maybe that is just my perception of him.

Jasper Loy

@TedShifrin Well, to summarise what the topic is about in one sentence, because I can't find a good description online?

Alexander Gruber

@JorgeFernández You're a victim to the sirens :(

Ted Shifrin

10:27 PM

Classically it was called geometric probability. Crofton's formula was the ur-Theorem in the subject. We're basically trying to discern geometric invariants of an object by averaging those of various slices and projections.

Jorge Fernández

hahaha

Ted Shifrin

Sorry, that was 3 sentences.

Jasper Loy

I see. OK.

Mike Miller

Just make it a run-on.

Ted Shifrin

@Jasper: The Gauss-Bonnet Theorem, in some sense, is another prototypical integral geometry theorem. So is Fary-Milnor. I'll be happy to answer further questions.

Huy

10:30 PM

@TedShifrin: I started with the first pages of GR today.

I'm very proud of my achievement.

Ted Shifrin

GR? @Huy

oh ... duh

I was thinking GT

Huy

:D

GT is for high school. I have an exam on GR soon.

Ted Shifrin

I told someone about the Foucault pendulum in terms of parallel transport and covariant derivative yesterday @Huy.

Huy

Cool. I'll ask you about it soon, maybe

Mike Miller

Tell me about it, @Ted

Chris's sis

10:32 PM

@N3buchadnezzar I look at this $$\lim_{x\to0}_{x>0} (\log(\sin(x))+e^{1/x})$$ and know the answer instantly without using Taylor series. How I did it?

Ted Shifrin

@Mike: Do you know about the Foucault pendulum?

Mike Miller

Yes.

Studentmath

If I have shown that Hilbert's cube is embeddable in $l_2$, is it suffficient to show that any set of sequences that act like Hilbert's cube in $l_2$ is nowhere dense there, in order to prove that Hilbert's cube is homeomorphic to a nowhere dense subset of $l_2$?

Chris's sis

@TedShifrin ^^^

Jasper Loy

@HipsterMathematician I am sorry!

Ted Shifrin

10:34 PM

So, think about carrying the pendulum around a latitude circle with the earth fixed (rather than rotating). A simple calculation will show that the swing vector field of the pendulum is essentially parallel (i.e., its derivative is almost all normal to the earth at that point). So walking the pendulum once around the latitude circle is parallel transporting a vector along that path (=holonomy).

Whoa, @Studentmath ... You've gone from 0 to 1000 very quickly in topology.

Mike Miller

Interesting, @Ted

Studentmath

@Ted did I? I am doing product spaces now..

Mike Miller

Did someone flag HipsterMathematician's comment? Because it's funny.

Ted Shifrin

I have no idea to what Hipster refers.

Mike Miller

I guess someone did.

I don't know what they refer to either.

Anonymous

10:36 PM

Yes, someone did

Mike Miller

Well, I'll be sure to punch @Jasper in the face now that HipsterMath can't. :)

Jasper Loy

I did not flag her, of course.

Mike Miller

I know.

Ted Shifrin

@Chris'ssis: I figure that something that is instantaneous for you will take me hours, so I won't try to do it in an instant.

Bungo

Did everybody see this delightful answer which provides a simple-looking integral that happens to equal exactly 22/7 minus pi? math.stackexchange.com/a/1078935/169852

Jez

10:37 PM

i thought it was a valid flag, it breaches the "be nice" policy, something i've been banned for a bunch of times

Jasper Loy

@HipsterMathematician I am sorry you got suspended. Of course, I did not flag you.

@Jez No, no, Hipster and I are good friends.

Jez

well, this is why the flagging system here is dumb. there's a lack of context.

Ted Shifrin

@Studentmath: I don't know what you mean by "any set of sequences that act like Hilbert's cube in $\ell_2$".

Jasper Loy

Can a moderator unban Hipster @snailboat?

Jez

people from all rooms get notified when it should just be regulars

Mike Miller

10:38 PM

@Jez Context matters on such things. If I called Ted a smelly jerk that nobody likes, he would probably smack me, and we would both be on our merry way.

Jez

i agree, i've criticized the flagging system a lot

halirutan

I guess flags are a pretty good way to get more people in the room.. I should remember that. When I'm bored next time and no one is there to talk, just flag something that was obviously not meant to be serious :-)

Ted Shifrin

You'll recall that Alec accosted me for being rude to Mike or Pedro totally out of context.

Mike Miller

How're you, @halirutan?

Ted Shifrin

LOL @halirutan. Not a way to win friends.

Alexander Gruber

10:39 PM

@JasperLoy why?

Anonymous

@JasperLoy Sure, okay.

Jez

@halirutan yeah that's another thing; false flags dont really get punished

halirutan

@MikeMiller Good. Thanks. Hope you are well too.

Mike Miller

Doing great!

Jasper Loy

@AlexanderGruber Oh, well, I don't think Hipster was being nasty to me. Just joking around.

Anonymous

10:40 PM

I did since it seemed like no one involved was offended

halirutan

I had hoped some real fight is going on here when I was pinged for the flags.

Alexander Gruber

@snailboat No problem, I was just wondering. Hadn't been following the conversation

Undo the Snowman

@snailboat agreed. I would have done the same thing if you hadn't beaten me to handling it :)

Jasper Loy

OK @HipsterMathematician you have been unbanned.

HipsterMathematician

I wasn't joking around @JasperLoy

Ted Shifrin

10:41 PM

Oy.

Mike Miller

Oh, HipsterMath wasn't joking. Let's ban her again, quick!

Jasper Loy

@HipsterMathematician OK. I am sorry. I won't ask you again that question.

HipsterMathematician

I appreciate.

When Marília stack exchange is created you can ask that

Jasper Loy

Anyway, the question I asked was 'When are you getting married?' That's all. For those curious.

Studentmath

@Ted well, I showed that Hilbert's cube is homeomorphic to $[0,1/n]^N$, which is a subspace of $l_2$. Now the points there are sequences $x_n$ so that $0\le x_n \le 1/n$ for every $n\in N$.

Now I am wondereing, if I show the set of these esequences is nowhere desne in $l_2$, that would suffice to show homeomorphism between Hilbert's cube and a now-where dense subset of $l_2$, right?

halirutan

10:43 PM

@JasperLoy Thank you. I was just searching when you mentioned @HipsterMathematician's name but found nothing.

Alexander Gruber

@HipsterMathematician 查雳? :-)

Jasper Loy

@AlexanderGruber Yes.

Alexander Gruber

Ahhh, it's a good day.

HipsterMathematician

Yeah grubs

Jasper Loy

There are so many users in this chat now.

Alizter

10:46 PM

@JasperLoy it must be for you

Jasper Loy

@Alizter For me? Are they here to hope that I will start studying calculus next Thu? =)

Alizter

Is that the first?

Jasper Loy

Yes, I intend to start studying on the first.

Don Larynx

@Jasp: Are you a freshman?

Alizter

No where near

Jasper Loy

10:48 PM

@DonLarynx No, I finished undergrad ten years ago. Planning to take GRE hopefully not too far from now.

Mariano is the only mod left from 2011.

Jorge Fernández

when do we see the results of the election?

Ted Shifrin

@Studentmath: I wasn't ignoring you. I was preparing rice pilaf in the kitchen. Let me read.

Jasper Loy

@JorgeFernández It's out already.

Jorge Fernández

where?

Jasper Loy

@JorgeFernández Meta.

Studentmath

10:54 PM

@Ted didn't think you did :P But I kinda figured out what I said is actually true. I think so, at least

Ted Shifrin

So, let's see, @Studentmath. To show a set $A\subset X$ is nowhere dense, given any $x\in X-A$, we must find a neighborhood with no element of $A$ in it.

Jorge Fernández

Oh, the three I voted for!

Ted Shifrin

Yes, tautologically, what you asked is true, @Studentmath.

Jasper Loy

@JorgeFernández Yes, I also voted for them. Too bad Thomas withdrew.

Don Larynx

I voted for two out of the three @Jorge, but originally voted for all three.

Studentmath

10:57 PM

In this case I know the set is closed, so it's enough to show its interior is empty

Jasper Loy