Mathematics

@JonasTeuwen I don't know. But cotton pillows are not good. And I even tried the very expensive type that changes shape to fit your head. But I realized shape is not important at all.

Jonas Teuwen

@JasperLoy It holds too much moisture?

user19161

@JonasTeuwen You mean my head?

Jonas Teuwen

@JasperLoy The cotton pillow 8-)).

user19161

@JonasTeuwen No, it sinks too easily, while latex does not. It has to be high enough yet not hard.

Jonas Teuwen

7:43 PM

@JasperLoy Mm... I usually pass out in 2 minutes when I put my head on the bed 8-).

user19161

@JonasTeuwen That's good!

Gigili

I just explained a whole question by posting over a million comments on someone else's answer and something meh happened.

user19161

@Gigili You might as well post another answer.

Gigili

@JasperLoy Well, I posted but I think the OP didn't notice someone else other than the answerer was answering his questions or something weird like that.

user19161

@Gigili OK, then have a beer!

Jonas Teuwen

8:03 PM

@Gigili Relax!

user19161

@JonasTeuwen I have begun to parrot you by telling others to have a beer.

Jonas Teuwen

@JasperLoy It is a synonym for "relax". 8-).

user19161

@JonasTeuwen Though I must say, I really hate beer. I like red wine. :-)

Jonas Teuwen

@JasperLoy Then have some red wine... But maybe the beer there is just shit.

anon

Is there something I'm not getting here? The math written looks awfully familiar to me, in the context of the eigenvalue approach to RH, so I'm not sure what's up.

Ed Gorcenski

8:07 PM

I need many beers. So many beers.

anon

hands Ed a beer

Ed Gorcenski

takes beer That'll be a good start...

user19161

@anon He needs many beers.

Gigili

somanibeers?

He's not here right now. Sorry.

user19161

@EdGorcenski I give you many-1 beers. So now you have many beers altogether.

Jonas Teuwen

8:09 PM

@EdGorcenski Plenty of beers at my place, if you are ever in the neighbourhood...

user19161

@JonasTeuwen It's neighbourhood if you use BrE.

Ed Gorcenski

I suppose I am technically within a neighborhood of you, for sufficiently large $\epsilon$

Jonas Teuwen

@EdGorcenski Yea, up to you if you think the $\epsilon$ is worth it 8-).

Ed Gorcenski

So, on-topic question for once.

Jonas Teuwen

And if the many as in your request is satisfied the question is: will the metric be the same to return?

user19161

8:15 PM

Also, many could be an infinite cardinal, in which case many=many-1.

Ed Gorcenski

I am taking an intro analysis class this upcoming fall, and the instructor is using Rudin's book. I have taken an analysis class before, about 5 years ago, did OK, and don't remember a damn thing.

anon

subtraction of cardinals is well-defined?

user19161

@EdGorcenski Which Rudin book?

anon

I guess it is when one's infinite and the other ain't.

Ed Gorcenski

Principles of Analysis

user19161

8:16 PM

@anon Sorry, I may be just BSing.

user19161

@EdGorcenski So what's the problem?

Ed Gorcenski

The class I am taking has the following course description: "The basic topology of Euclidean spaces; continuity, and differentiation of functions of a single variable; Riemann-Stieltjes integration; and convergence of sequences and series."

Do you think that the course will be sufficiently self-contained, as in won't require a whole lot of pre-requisite knowledge, other than general proof strategy?

user19161

@EdGorcenski Yes I think so.

Ed Gorcenski

Alright. I've read that the Rudin book is not a good introductory book, and I am beyond the introductory level, but damn if I don't remember a single thing from the class

user19161

@EdGorcenski When people say something is good or bad, that is not well-defined and must be interpreted in context.

Jonas Teuwen

8:19 PM

@EdGorcenski Mm, will be hard but you will probably be okay. All depends on the amount you desire to spend on it.

user19161

@EdGorcenski If you know about proofs then Rudin is an excellent book.

Jonas Teuwen

The book is okay. Just need some motivation (most important).

user19161

The harder the better. After all, why are you taking math if you don't crave for intellectual stuff?

Ed Gorcenski

Very true. I am half expecting that the class will be too simple; I am also half expecting it will be too hard. I no longer know what to expect.

user19161

@EdGorcenski That's good. It's exciting that way...

Ed Gorcenski

8:21 PM

The university that I am taking the course at has very strange course numbering schemes; technically, the class is coded as a graduate level class. In practice, however, it is almost exclusively taken by undergraduates.

Jonas Teuwen

@EdGorcenski Stop expecting and do your work. Do it well too.

user19161

Work = Force times distance. One has to put in effort and has to move in the right direction too.

Ed Gorcenski

Oh, there will be plenty of work to be done soon enough.

user19161

8:51 PM

@jonas Don't sleep too late, see you!

Jonas Teuwen

@JasperLoy Bye!

Ed Gorcenski

Aw man, I just wrote a detailed answer to a question thinking it was new, but then realized it was just a bumped question that will just fade into history again =(

Old John

9:07 PM

@EdGorcenski All questions fade into history :) ... as do we ...

Old John

9:47 PM

@BillDubuque Thanks for the answer to the Q about congruences, I think I have found enough evidence in Disq.Arith. to convince me that I haven't totally mis-remembered :)

Chuck Fernández

where can i learn about p-adic numbers?

Is the study of p-adic numbers a part of a branch of mathematics?

like number theory, algebra or smthing?

Ed Gorcenski

Mostly intersects with number theory and algebra

Old John

@ChuckFernández Also intersects with analysis - I am currently reading a book on p-adic analysis

Chuck Fernández

if I wanted to buy a book that teaches me the basics of the area, what books should i be considering?

Old John

@ChuckFernández there are loads of books with a chapter or two on it - and there are some good online (free) lecture notes

Chuck Fernández

9:59 PM

i want to buy one so people who go in my room think im smart

Old John

@ChuckFernández That is a stupid reason for buying a book!

Chuck Fernández

Do yu know a good one?

Ed Gorcenski

That's a wonderful reason to buy a book!

anon

relevant

@ChuckFernández much cheaper to just buy a couple dry-erase boards.

Ed Gorcenski

I dunno, do you think lawyers ever actually read all those books in their offices?

anon

10:02 PM

certainly not. but there's a difference between read and use.

Chuck Fernández

the white boards make you look like you are obsessed with math. Books make you look cool and smart at the same time

anon

you aren't obsessed with math if a grad textbook is your casual reading?

Old John

I feel really pleased with myself - I "solved" some things about p-adic numbers while I was out hill-walking today :)

Chuck Fernández

I have topology without tears on paper

it takes up a lot of space

so which one of the books you mentioned can be obtained for free?

Old John

This is good: maths.gla.ac.uk/~ajb/dvi-ps/padicnotes.pdf

And I recently thought that the best account of p-adics from the point of view of explaining why they are useful in number theory is in this: amazon.co.uk/…

user19161

10:11 PM

@OldJohn Yes, that guy's notes are very good...

Chuck Fernández

This looks good

thanks

Old John

@JasperLoy Indeed

Chuck Fernández

Have any of you been to an IMO or national equivalent?

Old John

@ChuckFernández No, I entered once when I was at school (not very successfully), but I was at university with a guy who won (back in about 1970)

Chuck Fernández

gold medal?

was his name grigori perelman?

Old John

10:16 PM

@ChuckFernández No - this guy: en.wikipedia.org/wiki/Bernard_Silverman

Chuck Fernández

He made his own wikipedia page

imo-official.org/participant_r.aspx?id=10185 hes really good. He scored number 4

Jonas Teuwen

@ChuckFernández Seriously?

Chuck Fernández

nope srry it wasnt him

he id edit it however

did*

the person who wrote it was Nichola Beale

Nicholas*

Old John

@ChuckFernández He certainly picked stuff up a lot quicker than I did at Uni - but he was a good friend

Chuck Fernández

Japan got a very bad result in the 2012 IMO

Jonas Teuwen

10:23 PM

@OldJohn When is the last time you saw him?

@ChuckFernández NL did very well!

Chuck Fernández

@JonasTeuwen it was 53 of 100

I want to go the the IMO in 2013

Jonas Teuwen

@ChuckFernández What was? imo-official.org/country_individual_r.aspx?code=NLD

Old John

@JonasTeuwen Several years ago - I was in email and phone contact with him until about a year or so ago - he is now a chief scientific advisor to the UK government, and I don't think he has time to talk to little people like me anymore

Jonas Teuwen

@OldJohn Hmm, is he someone that wouldn't want to talk to "little people"?

Chuck Fernández

@JonasTeuwen oh i thought you mean new zealand

Jonas Teuwen

10:27 PM

@OldJohn The scientific advisor also needs friends :-).

Old John

@JonasTeuwen No - he is just so ridiculously busy, I think

Jonas Teuwen

Okay. Well, he will not be the scientific advisor forever.

Old John

@JonasTeuwen true!

Chuck Fernández

I have a lot of trouble with the geometry questions

any tips?

Old John

@ChuckFernández what sort of geometry?

Chuck Fernández

10:29 PM

can i give you an example question?

Old John

@ChuckFernández Fire away - we may or may not be able to help

Chuck Fernández

Let $ABC$ be an acute triangle let $BE$ and $CF$ be heights of the triangle ($E$ is on $AC$ and $F$ is on $AB$). two circles pass through F and A and are tangent to line $BC$ in points $P$ and $Q$ such that $B$ is between $C$ and $Q$. Prove Lines $PE$ and $QF$ intersect on the circuncircle of triangle $AEF$.

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$Mathematics$ Mathematics