Mathematics - 2014-12-06 (page 2 of 6)

Tom Cruise

05:00

I think you are around 25 years old

Twink

why?

Tom Cruise

and in the USA

Twink

xD

Tom Cruise

and a student

Twink

you're very wrong

Tom Cruise

05:00

darn

Twink

English isn't even my native language :)

Tom Cruise

oh you must be French

Twink

nope :)

Tom Cruise

like Galois

Twink

French isn't my native language either

Tom Cruise

05:01

but you speak french

Twink

many people speak french

Tom Cruise

dude come on

you are 100% a graduate student

I have no doubt

Twink

you should

:)

Tom Cruise

you're asking about Hilbert spaces

therefore you are a graduate student

Twink

Hilbert spaces are in many books, I don't need to be a student

Tom Cruise

05:03

because who else would care about Hilbert spaces

Twink

me :)

Tom Cruise

so you hate math, but you do math for fun...

Twink

no, I just do it to torture myself

Tom Cruise

you're crazy

Twink

not for fun

yes I am :) there you go, now you got some right information about me :)

Tom Cruise

05:05

so what is your goal?

Twink

I already told you that

to torture myself

I'm masochistic

Tom Cruise

I dont believe that

you are probably a genius

Twink

Tom Cruise

you are a gay masochistic genius

Twink

I wish

I wish I was the third thing that you said

and I'm the first two

I'm a gay masochistic dumb :(

Tom Cruise

05:09

but you know about some graduate level math

Twink

if you analize my profile, there are only question but no answers about that level of math

what does that mean to you?

Tom Cruise

you are a beginning graduate student

Twink

nope

the answer is that I'm dumb

Tom Cruise

that doesnt explain anything

Twink

that's why I only ask but not answer

well that's enough talking about me

Tom Cruise

05:12

you are a student or are recently graduated from undergrad

Twink

now talk about you

Tom Cruise

I am working on open problems

in topology

Twink

are they hard?

Tom Cruise

yes very hard

other smart people have worked on them before

so I have to be smarter than them

or at least more clever

Twink

do you have good notes?

Tom Cruise

05:16

not really

Twink

what is your worst note?

Tom Cruise

when I scribble all over the page and write curse words all over it

in frustration

Twink

xD

Tom Cruise

I thought I had a good proof one time

and I was happy

then 2 hours later I thought of the flaw

and I was sad

this is the life of a mathematician

mostly failure

Twink

what a terrible life

Tom Cruise

05:21

:(

Twink

are you depressed?

Tom Cruise

not in general

but it is depressing when I cannot prove something

Twink

I guess so

Tom Cruise

but tonight I am rocking out

this is my thinking

Twink

are you going to party tonight?

Tom Cruise

05:24

our abstract logical faculties may be the only thing separating us from other animals

so it is worth dedicating our lives to mathematics

it may be the reason we exist

Twink

the reason we exist is the Bing Bang

Tom Cruise

but we have particular abilities that other animals lack

maybe we were put here to do math

Andrey Kaipov

The giant squid has the largest eyes in the world. Maybe it was put here as an oracle to see the future for us!

Tom Cruise

do you like wine?

Twink

because we evolved

we were monkeys before

I like red wine

Tom Cruise

05:28

but why did we evolve the way we did?

Twink

because of nature

Tom Cruise

why do we have the ability to do math?

I am drinking a Napa valley Cabernet

California

Twink

do you have friends?

Tom Cruise

not anymore

Twink

why

Tom Cruise

05:30

I used to

but now all I do is math

Twink

why?

Tom Cruise

because I am a graduate student

Twink

so?

you can be friends with your classmates

Tom Cruise

I will not get my PhD unless I prove something major

Twink

you're a PhD student?

Tom Cruise

05:31

yup

Twink

how old are you?

Tom Cruise

24

first grade?

Twink

first year xD

Tom Cruise

2nd year

Twink

why?

you're too young

Tom Cruise

05:33

yes but I had too much fun when I was an undergrad

Twink

did you enter directly to PhD?

Tom Cruise

now I am like a monk

Integrator

I'm $18$ and $\sqrt{2}$

Tom Cruise

@Integrator you are 19?

when I was 19 I was a trainwreck

Integrator

No $18+\sqrt2$

Twink

05:34

do you like lady gaga?

Tom Cruise

yes so you are 19

not really

Twink

why not

Integrator

$18+\sqrt2=19$ ??

Tom Cruise

$=19.14....$

19.41...

I like old music

Twink

I'm packing

Tom Cruise

05:36

where you going?

Twink

I'm traveling tomorrow :)

can't tell

Tom Cruise

lol

I went to Seattle recently

very nice

Twink

I love to travel

Andrey Kaipov

did you go to the fish market?

Tom Cruise

yes

Andrey Kaipov

05:38

did you pet that golden pig Rachel?

Tom Cruise

I think so

Andrey Kaipov

and then did you walk further (east?) to that russian bakery "Perogi Perogi"?

Twink

I won't forget my toothbrush this time

Tom Cruise

YES!!!

are you stalking me?

you have to brush your teeth

or girls won't like you

Andrey Kaipov

no but that's the route i took when i went to seattle lol

FreeMind

05:39

@robjohn Could you please implement the method you'd told me previously for that integral?

Andrey Kaipov

then i went to that totem pole thing

Tom Cruise

I remember that too

robjohn

@FreeMind which integral?

Tom Cruise

if you go north into British Columbia there are lots of totem poles

there was a hot girl in my class

FreeMind

@robjohn mathoverflow.net/questions/188827/…

Tom Cruise

05:40

and I didnt realize I had stuff in my teeth

Twink

I don't like girls

Tom Cruise

why not?

FreeMind

@robjohn This problem is seriously on my nerve! days and nights pass, I get nowhere!

@robjohn There is a complex integration method to find a closed form solution, but I have to approximate it and find $h(z)$ with fourier series!

Tom Cruise

@FreeMind thats why I dont do complex analysis

Twink

I can't tell you now, there are many people now

but I already told you..

Tom Cruise

05:42

ok because you are like Tom Cruise ;)

FreeMind

@TomCruise What do you mean? I do not remember you telling me about complex analysis!?

Twink

yes

Tom Cruise

@FreeMind cause I dont know much about it

its ok Twink, you are ok in my book

FreeMind

@TomCruise That damn complex exponential in the question is dancing on my nerve badly!

@TomCruise Even treating it as two real parts sucks!

Twink

which book?

FreeMind

05:45

I need the $h(z)$

@robjohn Any suggestion?

Twink

@TomCruise which book?

Tom Cruise

its a figure of speech

I just finished my bottle of wine

Twink

and what does it mean?

remember that English is not my native language

Tom Cruise

"you are ok in my book" means roughly "I like you"

Twink

you like me?

now I understand your user name

FreeMind

05:53

@robjohn What happened?! :|

Tom Cruise

I am Tom Cruise

@Twink what red wine do you like?

Twink

I don't know

I don't know their names

Tom Cruise

pinot noir?

cabernet sauvignon?

Twink

¬¬

I don't know their names

Tom Cruise

$\neg\neg$

Twink

05:55

I've just drunk it sometimes in some places

and I like it

Tom Cruise

you are a drunk?

a lot of mathematicians are drunks

FreeMind

@TomCruise Who says that?

Tom Cruise

because they cannot handle failing to prove what they want to prove

being a mathematician is mostly a life of failure

except for the very best mathematicians

Twink

lol I'm not a drunk

and I'm not a mathematician

Tom Cruise

you are a young student

FreeMind

05:59

@TomCruise You old? LoL!

Twink

I gotta go to bed

Tom Cruise

@FreeMind no I am 24

Twink

I need to rest for tomorrow

:D

Tom Cruise

ok brush your teeth

Twink

good night everyone

Tom Cruise

06:00

night night

when I go to the bar later what pickup line should I use?

I am a mathematician?

come with me if you want to live?

Omnomnomnom

"I wanna your antiderivative so I can get the area beneath your curves"

FreeMind

@TomCruise Who are you talking to? :D

Tom Cruise

@Omnomnomnom oh wow I will try that

Omnomnomnom

Ha! please don't

Tom Cruise

@FreeMind whoever is listening

LOLOL

FreeMind

06:04

Where do you live? TOM?

Tom Cruise

That is great

FreeMind

@TomCruise ?

Tom Cruise

I should tell that to my calculus students

Omnomnomnom

Or if you need to break up with someone, "I'm making a you-substitution"

"... and now you're dx"

Tom Cruise

LLOL

@FreeMind I live in USA

FreeMind

06:06

@TomCruise That's obvious, in what state!

Tom Cruise

california

duh

FreeMind

@TomCruise Oh

Tom Cruise

I drank too much wine

FreeMind

@TomCruise I bet you've never drunk :)

Tom Cruise

isnt it funny how your ability to do math disappears when you drink?

does this happen to everyone?

Omnomnomnom

06:10

Didn't your parents tell you?

You should never drink and derive

FreeMind

@Omnomnomnom Once I drank, derove badly :D

Tom Cruise

ok I heard that one before

yeah I drank and got a dui

thats pretty bad

yay

alright I am going downtown to find some girls

goodnight!

Omnomnomnom

Good luck

Tom Cruise

they need luck to resist my chiseled physique

and math skills

adios

Qix

06:50

I'm reading about i and complex numbers, and something crossed my mind.

Is i equivalent in any way to pi/2?

For context, I'm reading this explanation, which seems to be doing a good job thus far.

Gustavo Montano

Equivalent? I would say not.

Oh I see where HILY SHIT

3

That was a huge thunder strike! Apologies.

I see where you may be coming from. Multiplying a vector by $i$ will cause the vector to rotate by $\frac{\pi}{2}$ radians.

Qix

Huh. Math just became fun again.

And that's scary seeing as how I'm a software engineer.

Thinking of numbers as two-dimensional is something that will take me a few days to process...

Gustavo Montano

Oh that's interesting. I am a pure mathematician and have taken a HUGE interest in programming.

I feel there is a strong connection in terms of problem solving.

Qix

Oh of course.

You'd enjoy graphics programming and shaders. Learn your basics, and for your dessert toy around with this fun little thing.

Gustavo Montano

07:06

I've spent the last week learning HTML and CSS. I dislike it.

Qix

Something tells me you'd enjoy playing with it.

Gustavo Montano

I feel like there are a number of ways to do the same thing. And that's annoying. Especially with all the ways one can structure CSS/

Qix

@GustavoMontano Because HTML is a data markup language, and CSS is, well... also kinda the same thing.

Gustavo Montano

OH WOW!

This is very topological. (Topology is my favourite branch of mathematics).

This is amazing.

What language?

So it's a shader. Hmmm.

Qix

Yep; again, read up on the basics, learn about the shader pipeline, and GLSL (a language similar to C that is compiled and ran directly on graphics cards, implementing a graphics pipline, or 'program')

Gustavo Montano

07:09

Gosh, I don't know if I have the time.

Learning these things takes a lot of time.

Interesting none-the-less.

Qix

Basically, video games are basically

Game Logic -> 3D geometry (a bunch of *points* tied together using *indices*) -> OpenGL (or similar libraries) -> Your graphics card -> Vertex Shaders (which are programs you write that live and run on your graphics card in order to modify the given vertices must faster than your CPU can) -> *other graphics voodoo* -> Fragment Shaders (takes the "rendered" pixel data and changes colors given a number of things, such as where the vertex the pixel was rendered from is in 3D space, etc.) -> *more graphics voodoo* -> your monitor

Pretty fun stuff. :)

Gustavo Montano

Sounds very difficult@

Qix

It... is. Well, complex; difficulty is relative :)

For instance, I'm learning about FFT so I can implement it in OpenCL (basically a programming language that runs on your GPU -- again, for increased performance)

FreeMind

@robjohn You didn't reply?!

Qix

That rabbit-hole'd all the way down to imaginary numbers

Gustavo Montano

07:15

What? Really? Interesting.

Qix

Yeah

Committing to a challenge

So our friend UserX deemed himself to have no self control and had himself banned

Qix

@GustavoMontano Also, I wish I reflexed my interjections directly into words on my keyboard like you can...

Gustavo Montano

Hahahah! It is currently thunder storming in Sydney, Australia.

Committing to a challenge

It is currently gently raining in Brisbane, Australia

Gustavo Montano

07:18

The difference in speed of sound and light always gets me.

I see the flash....a few seconds later. BOOOOOOOM

Committing to a challenge

The storms last Thursday did series damage to my university campus, and I was there xD

Hail the size of fists

Balarka Sen

@Committingtoachallenge eh? UserX got himself banned from chat?

but how?

hell you guys filled the mathematics chat with nonsense

thinks he just came into the wrong room

@MJD: Euler in his later days went blind. I think he didn't know that he was really wearing his shirt on his head. — Asaf Karagila Nov 19 at 6:18

LOL!

Gustavo Montano

07:45

Hahah!

Mike Miller

Flag as spam

Balarka Sen

08:10

@MikeMiller I am not sure why that doesn't work. The fundamental group of the countable bouquet $\wedge S^1$ is $\Bbb Z \star \Bbb Z \star \Bbb Z \star \cdots$, not?

Balarka Sen

08:22

@MikeMiller I don't think it'd imply so. The circles in the boquet are not retractable to a point, but the circles in the earring are, as the earring is equipped with the subspace topology from R^2, a simply connected space.

Your argument that my solution is incorrect is flawed.

Huy

08:42

@Venus: $$\int_{-\infty}^\infty \cos(x^2) \, \mathrm dx = \lim_{a \to \infty} \int_0^a \cos(t) \cdot t^{-1/2} \, \mathrm dt= \pi^{-1/2} \lim_{a \to \infty} \int_0^a \cos(t) \int_{-\infty}^\infty e^{-tu^2} \, \mathrm du \, \mathrm dt= \pi^{-1/2} \lim_{a,b \to \infty} \int_0^a \cos(t) \int_{-b}^b e^{-tu^2}\, \mathrm du \, \mathrm dt.$$
Then apply Fubini's theorem.

Sven

09:01

Hi, given the recurrence relation $f(2n) = f(n) + f(n+1) + n$ and $f(2n+1) = f(n-1) + f(n) + 1$, how can I find the largest n for f(n) = x?

Venus

09:16

@Huy Very nice. Thanks. ^^

@Huy @Chris'ssis @robjohn @DanielFischer @Hippalectryon @BalarkaSen @Integrator @WillHunting I create an artistic answer without a single word. ^^

3

A: Is there other methods to evaluate $\displaystyle\int_1^{\infty}\frac{\{x\}-\frac{1}{2}}{x}\ \mathrm dx$?

\begin{align} \int_1^{\infty}\frac{\{x\}-\frac{1}{2}}{x}\ \mathrm dx &=\sum_{n=1}^\infty\int_n^{n+1}\frac{x-n-\frac{1}{2}}{x}\ \mathrm dx\\[9pt] &=\sum_{n=1}^\infty\left[1-\left(n+\frac{1}{2}\right)\ln\left(\frac{n+1}{n}\right)\right]\\[9pt] &=\sum_{n=1}^\infty\left[\ln e+\left(n+\frac{1}{2}\righ...

@r9m I won't leave a single word in the comment. So let's chat here. Honestly, I have evaluated that integral when I posted the problem in the cited link ^^

r9m

@Venus 'kay kay :) .. the proof by Hypergeometric (in your post) and The Artists proof in the OP are essentially similar imho :) ..

Venus

@r9m Indeed

I doubt that can be done without using Stirling

r9m

@Venus I see no way other than Stirling either (direct or indirect) .. :)

Venus

@r9m I could be wrong, so let us wait and see. :)

r9m

@Venus I wait too .. I wanna see all possible solutions to this Q :D

Venus

09:30

@r9m Actually the OP copies pastes his method from the book Inside Interesting Integrals

r9m

@Venus I see .. I haven't read the book that carefully ;) .. (y)

Venus

@r9m I read it coz it came from my bf ^^

@r9m @DanielFischer @KajHansen Is there a $\LaTeX$ code for a red-colored heart-shaped symbol?

I don't know is this a correct English or not : 'a red-colored heart-shaped '

r9m

@Venus AWESOME !!! :D ..

Huy

@Venus: tex.stackexchange.com/questions/139733/…

Venus

09:46

@Huy It doesn't work on mse

None of them work

Huy

@Venus: No, it doesn't. MSE doesn't allow arbitrary LaTeX code.

Venus

@Huy I want a code that works here

@Huy $\Large\color{red}{❤}$

3

It turns out so easy

Huy

@Venus: Are you sure that will work on every PC and every browser?

Venus

@Huy Dunno. How about the other? @WillHunting @r9m @KajHansen @DanielFischer

Kaj Hansen

The one you just did works

r9m

09:54

@Venus works for me ! (win 7, chrome Version 39.0.2171.71 m)

Swapnil Tripathi

Hello everyone!

Hey @Kaj

Kaj Hansen

Hey @SwapnilTripathi. Going to bed soon

Swapnil Tripathi

Haha! I just approved an edit which should have been rejected! -_-

r9m

@TomCruise haha ! =P

Kaj Hansen

Was it the bot? @SwapnilTripathi

Transcript for

$Mathematics$ Mathematics