Mathematics - 2017-06-11 (page 9 of 9)

Krijn

20:00

Well I'm bad at most topology soooo

Does that cut any cases?

Balarka Sen

algebraists are out

Daminark

Wait damn

No keep algebraists

Eric Silva

what is an algebraist

Daminark

@s.harp it's a space sloth lol

Eric Silva

is it some kind of food for analysts to eat?

cause I'm hungry

Krijn

20:01

@EricSilva A sadomasomathematician

Balarka Sen

@Eric a procult revolutionary group who writes vulgar things and passes it off as interesting math

Alessandro Codenotti

Hi chat, what's going on?

Daminark

Algebraists are analysts who made better choices somewhere early in the road

Eric Silva

@Daminark t r a s h

Balarka Sen

"The Vulgarization Functor"

Daminark

20:03

Or perhaps it's better to say analysts were algebraists who screwed up somewhere

Balarka Sen

One which transfers beautiful geometric object into infinitely vulgar $\infty$-stuff

I don't like analysts but I like them better than algebraists

Krijn

Lexicographically, algebra > analysis

Daminark

Draw a commuting diagram which resembles a picture of the object in question

Akiva Weinberger

Just gonna point out that we reached the 7 billionth person around late 2011/early 2012

and now we have 7.5 billion people

Daminark

Whoa

That's insane

Balarka Sen

20:05

In MSE?

Akiva Weinberger

I think people think the 7.5 billion mark was reached a few weeks ago

Daminark

@Balarka in irl

Akiva Weinberger

Obviously we don't know exactly when

Eric Silva

@Daminark there are people who arent on MSE?? what r they doing with their time???

productive things?

Alessandro Codenotti

@Daminark real life is boring

Krijn

20:05

They expect 8 billion by 2025

Astyx

@EricSilva Obviously a joke

Semiclassical

especially since the likelihood of someone being born or dying in the span of this conversation is pretty good

Balarka Sen

@Daminark You have a grammatical error

Daminark

@EricSilva I mean probably not being productive either

Astyx

I think every second one person dies and two are born

Daminark

20:06

Right I meant to say in real irl

Balarka Sen

what is productive?

Astyx

These figures might be outdated though

Semiclassical

I actually do have a math question I should try to figure out, but it's more Lambert-W stuff

Sha Vuklia

@Hippa yea I have to leave it for now, I'm sorry. I don't have time.

Semiclassical

specifically, more branch-structure / real-imaginary part madness.

Sha Vuklia

20:07

Balarka Sen

We'll die before 2100 anyway

Sha Vuklia

Guys, where do we use $\cos\omega t\sin\omega t$ in $\vec E_1\cdot\vec E_2$? I only see "like" terms, like $\cos\cos$ and $\sin\sin$.

Eric Silva

@Balarka i give us till friday tbh

Krijn

@BalarkaSen No i wont

Semiclassical

Won't those show up in the expansion of 9.9?

Schematically, you've got $(A_1\cos \omega t+B_1\sin \omega t)(A_2\cos \omega t+B_2\sin \omega t)$.

Balarka Sen

20:10

@Krijn one does not simply contradict stephen hawkings

Semiclassical

And that multiplies out to four terms, two of which are sin cos

Krijn

@BalarkaSen Yeah you do

He's a physicists

He doesn't know about this stuff

Semiclassical

(The point being that you won't end up with the $A_1 B_2$ or $A_2 B_1$ terms after time-averaging.)

Sha Vuklia

uhm okay let me see

ohhh

Semiclassical

:)

Sha Vuklia

20:11

right, I had completely forgotten that I can expand it

Faust7

anyone know the function that maps Q to the natural numbers off hand?

Sha Vuklia

right, sorry, that was quite a stupid question. but I've been studying since this morning, so that might explain it :P

Semiclassical

heh, it happens.

Balarka Sen

stephen hawking's face is slowly turning into butter as time evolves though. but at least he's alive and predicting our death

Semiclassical

ugh, I need to stop listening to this song. it's a very good/effective song, but it always leaves me in a down mood.

Balarka Sen

20:15

you should listen to the song we dug up yesterday or something

Semiclassical

which one was that?

Balarka Sen

it's infinitely catchy, so definitely going to remove song-cache from your head

here you go

Semiclassical

I should watch one of those bad lip reading videos.

Daminark

Look up "Tweeted Love"

Semiclassical

Though so far this song seems more like 90s memes.

Daminark

20:19

'tis funny

Faust7

How infinitely?

Krijn

@BalarkaSen I just tested my life expectancy online, and I will make it to 2096 :(

God dammit

Faust7

depend show old u r that might be rather impressive

Balarka Sen

you will become dead

Daminark

@Faust7 $\aleph_{31}$

Faust7

20:20

lol

Krijn

@BalarkaSen I am become Death, destroyer of worlds

Daminark

Rip in sad react

Faust7

can you integrate something thats nowhere continous?

Balarka Sen

nope

Daminark

Riemann integral requires continuity almost everywhere

Astyx

20:24

$\chi_{\Bbb Q}$, no ?

Eric Silva

#Lebesgueknewbest

Balarka Sen

Riemann integrable iff continuous almost everywhere in fact

Faust7

but there are other ways to integrate

Astyx

Lebesgue

Faust7

Lebesue

Eric Silva

20:25

for Lebesgue ur fine

Faust7

or w.e

Daminark

Lebesgue integral requires measureable which gets you a good deal more functions

Eric Silva

i have never in my life encountered a function which is not measurable

Alessandro Codenotti

Me and my classmates made one of those "who are you? I'm you but stronger" memes with Lebesgue and Riemann

s.harp

nobody was stronger than riemann

Astyx

20:26

Lebesgue integration theory is beautiful imo

Faust7

book?

s.harp

except tuberculosis

Balarka Sen

i dunno any of it :(

Eric Silva

@Daminark although sometimes when people say "integrable" they want the integral to be finite but idk how wide spread this is

I had a conversation with a professor over how sad it is that Riemann died so young

Astyx

@BalarkaSen You don't know Lebesgue ?

Eric Silva

20:27

the things that man saw...

s.harp

@EricSilva it is consistent with ZF that every function is measurable

Eric Silva

ya ik

Balarka Sen

only superfically, @Astyx

Astyx

Ah right, you probably know as much as me then :p

Faust7

i remeber a formula that we had to use a wierd integralfor

from a dif geo class

Daminark

20:28

Yeah our TA thought of integrable as finite integral. Though thanks to Marianna I'm even chill with functions that are valued on the extended reals

Eric Silva

cuz ur TA is one of the soug disciples probably

Faust7

anyone know of good book to explain it?

Eric Silva

there's this book by wilcox

Daminark

Yeah she is

Eric Silva

called fourier series and lebesgue integration or something

Alessandro Codenotti

20:28

Functions to the extended reals make a lot of measure theory theorems nicer

Eric Silva

it's a quick read

and nice

for more read like royden or something

Daminark

I used mostly Rudin, I think

Eric Silva

oh ya and rudin real and complex

although i didnt care as much for it

Alessandro Codenotti

@s.harp that got dark quickly

s.harp

its funny that most geometry colloqium talks at my universtiy start with "actually riemann was thinking about something similar to this when he did this and that"

Eric Silva

20:32

there are a few mathematicians who were thinking leaps ahead of their time

Riemann is one

s.harp

the guy died when he was 39 years old

Faust7

let$ f(x)=: x if x \ in mathbb {Q} f(x)=-x if x \in \mathbb {R\Q}$ how do i show that f(x) is continuous at 0 (assuming it is)

Eric Silva

Galois is another

Daminark

I mean I mostly just rolled with my professor's lectures

That plus TeX'd notes, which my friend would occasionally add on Rudin stuff when Marianna wasn't completely clear

Eric Silva

@Faust you can squeeze the limit

Faust7

20:33

oh

rhs and lhs both aproach 0 and is 0 at 0

thx

Daminark

Oh @EricSilva someone did find a book called Evans, which seems a bit more Marianna style

Eric Silva

L.C. Evans?

Daminark

Maybe

It's called measure theory and the fine properties of functions

Eric Silva

ya same dude, he's written a lot of things

Faust7

from that statement its hard to tell if thats a good thing or a bad thing

Daminark

20:39

Is he the one who did the PDE and variations book you talk about?

Eric Silva

yup

Daminark

I see

Eric Silva

and a book on weak convergence methods i took a couple whacks at back in winter

Daminark

Dank

Eric Silva

@Daminark are ur grades up

Daminark

20:42

I'll check

Eric Silva

mine aint

Daminark

Same

Hippalectryon

@ShaVuklia alright :-)

Daminark

Odd, did evals and my grades in a few classes have already been decided

Likely sent to the register

I mean they're just a mess, remember add-drop

I'm grateful for that delay because people posted memes about it being late, which then gave me time to hop into core bio

Eric Silva

oh i didnt know

i just had to drop this year

Daminark

20:47

Lel

I was aiming for a specific core bio section which closed 30 seconds after I got it

As it stands I'm registered in Nori's complex, that bio class, and Shotton's algebra

I'll have to pink slip into logic

And find what to replace complex with. It seems like Smart's section was slow by the standards of most complex professors, but even Nori is likely to be mostly subsumed by bootcamp

Astyx

Villani will probably be my deputy

Eric Silva

is deputy a government thing

Astyx

Yup

Equivalent of MP in the UK

I don't know about the US

Eric Silva

idk what mp stands for

Daminark

Congressman, I think?

Eric Silva

20:52

oh makes sense

Astyx

Member of parliament

Daminark

MP should be Minister of Parliament if I remember right

Eric Silva

what party did he run for

Daminark

Oh I see, lol that makes more sense

Astyx

Macron's

Faust7

20:53

u guy live in the old country?

Astyx

En Marche

Eric Silva

ohhhh weird

i wonder why he's doing political things

Astyx

I guess he's bored

Or he lacks attention

Daminark

Lel

Eric Silva

what is en marche's political leaning

is it like neolib

like our dem party

Astyx

20:57

Mmm I don't know what I'd compare it to

Daminark

I've heard it described as liberal/center

Eric Silva

smells like neoliberalism to me tbh

Daminark

Your statement smells like disapproval

Faust7

is the power set of a countably infinite set uncountably infinite?

s.harp

@faust7 the power set is always strictly larger than the orginal set

Daminark

21:00

Yeah, specifically $\aleph_1$

Faust7

that halfanswer my question

Daminark

It bijects to the reals

Faust7

i think your saying yes?

s.harp

@Daminark the reals do not necessarily have cardinality $\aleph_1$

Faust7

ok thx.

wait

Daminark

21:01

Oh lol I roll with generalized continuum hypothesis

Alessandro Codenotti

@s.harp dami has this bad habit of assuming (G)CH

Eric Silva

@Daminark there's good and bad, I don't disapprove necessarily, but I don't approve either (I'm a latin american, how could I be fully approving given the history of how neoliberal policies have affected latin america)

Faust7

no im good thanks.

Daminark

I see @EricSilva, makes sense. I haven't yet read up on it much but I've heard that the economic policies were merpy at best

@AlessandroCodenotti it's not a bad habit!

Alessandro Codenotti

that's debatable

Eric Silva

21:05

that's one of those things where there are super good arguments on either side

Daminark

It's a good and deliberate choice! Harumph

Eric Silva

that is whether or not assuming (G)CH is good or bad

Daminark

Lel

Eric Silva

idk anything about them though

jus that people are on either side

Daminark

If we get into that in logic at all I'll let you know

Though idt it gets too deeply into specifically stuff that you can add to ZFC

Eric Silva

21:08

ask smart

Daminark

It's probably more general model theory

Eric Silva

he's a closet logician

Daminark

Oh nice

Lol he's got tenure now, right? No need for the closet

Eric Silva

he very much does research in PDE

the "closet logician" comment is how he described himself to me at some point

he started in logic in grad school and switched later

Daminark

We do need more logicians, we've only got 2

Ah, makes sense

I've actually considered going the logic direction, we'll see how this goes

Eric Silva

21:13

we are young, we can explore

Astyx

yet

Daminark

This is true. Life of the auditor intensifies

s.harp

Eric Silva

that looks more like a gator to me

Astyx

A caiman

Eric Silva

21:16

it doesnt look that much like a caiman

at least not the caimans that lived around me growing up

Astyx

I have this great pun that only works in french, feel my frustration

Mmm all the caiman that lived around me growing up looked like that

Eric Silva

the caiman near me were kind of small and derpy i guess

Alessandro Codenotti

that's oglaf if anyone's wondering, a (very NSFW) webcomic

Astyx

derpy ?

Eric Silva

they kinda cartoonish and weird

oh you know what, the one in the comic looks like a black caiman

from the amazon basin, although unsure if that's actually a caiman or just called a caiman

but those basically looked the same as all the alligators that lived around me so idk

s.harp

21:21

crocodilian.com/cnhc/cbd-faq-q1.htm

Eric Silva

oh yeah, i forgot, the teeth that poke up are important

mathvc_

Could anyone help me to diagnose my solution to a question?

1

Q: Homology of two 2-genus with identified their boundaries

Compute the homology groups of the space $X$ that is the union of two similar 2-genus ($M_2$) such that their boundaries have identified via the identity map. Here is my solution which I am not sure. I have considered the pairs $(A\cup B, C\cup C)$ such that $C$ is the boundary of both them. So ...

Zee

@Daminark I won't allow you to become a logician

@s.harp Link for comic?

Daminark

21:37

Why not? :'(

Zee

@Daminark couse, your better off doing other things, even algebra is better than logic

Plus all the deep questions of logic are answered, all else is philosophy

Daminark

I mean that isn't quite true, there's work to be done in logic (especially mathematical logic). Plus I'm chill with philosophy.

Zee

I know your chill with philosophy that's why am concerned about you...

ok, let me try to explain this

You tend to seek the most abstract and sterile parts of math, which is not bad but

The people who blaze the trail , tend to work in more applied areas

For example, set theory was born out of work on the Fourier transform

Grothendieck work was born out of work on several complex variables

Daminark

[citation needed for set theory]

And I mean I don't really have the talent to be much of a trailblazer

I just want to think about dank stuff

Zee

You don't need talent to be a trailblazer, you need talent to learn dank stuff, trail Blaise's only need to be philosophically minded

Anyway here is your citation, it doesn't strictly support what I said but there is a great deal of overlap

en.m.wikipedia.org/wiki/…

Daminark

21:50

That's like, pretty false, you have to be creative to come up with new things

Zee

Creative is nothing but to have philosophical mindness

Fargle

Oooooooooh, this looks like a fun debate.

arctic tern

you and I have different definitions of fun

Semiclassical

Eh. I find debates about creativity pretty dull, for the simple reason that they generally don't create anything.

Fargle

everything I say in here should have an assumed sarcasm tag

Daminark

21:53

The "ooooooooooh" made it sound more genuine than you intended

Semiclassical

^

Fargle

I don't think I've been genuine since 2009.

Oh well, suum cuique.

Zee

This isn't a debate about philosophy or creativity, I just wanted to note that the most abstract parts of mathematics have their roots in more concrete areas

Fargle

Sure, but that doesn't devalue approaching pure mathematics from a pure perspective.

It just shows that there are multiple paths.

Zee

Am not taking about pure and applied mathematics

Am taking about mathematics and then fringe mathematics that tend to be highly abstract, like logic

Fargle

21:56

I'm not entirely convinced that that's a particularly useful or fine categorization, though.

Daminark

And I mean, that's what uncreative people do, if they can't create something they talk about creativity. But yeah I mean, people who create them often are inspired by something more concrete but the people who just follow need not be based similarly in more concrete things. It's there, just go for it

Zee

I agree

I suppose if all your interested in are technicalities then ignore my advice

Fargle

I would also note that surely there are also many examples of the abstract informing the concrete.

Daminark

I'm really likely to be more in the latter category, I want to be a person good at puzzles and coming up with new things and whatnot, I'd swap my currently self with someone who's good at that in an instant, but experience shows that I'm just not too good at it, so I've been pushing for stuff I can do better

Fargle

Though I grant I know much less about mathematics than the average user in the room.

Zee

22:01

Says the 20 years old guy

Fargle

I'll shut up now. :)

Zee

Bro your 20 , don't limit yourself

Daminark

Uh, I wouldn't be surprised if Fargle is also 20 so which of us did you mean @Zee?

Zee

You

Daminark

Ah, I mean I guess

Semiclassical

22:03

oh god now i'm remembering that i turn 30 on the 21st

aaaggghhh

Daminark

Lol our birthdays are close @Semi

Fargle

Before I do shut up, I'd just like to agree with Zee on this one, @Dami.

Zee

@Semiclassical 30 is old, but then again you got people discovering things in their 50s

Fargle

I have long considered myself, and have been considered by others, quite a gifted boi. Egotism notwithstanding.

Semiclassical

I'd freak out more on this but I'm actually in my late day yawn stage.

Fargle

22:04

Based on what I've seen, you're a faster learner and a more mathematical thinker than I am. Do not make the mistake of selling yourself short.

s.harp

sell yourself short you'll put in more effort to catch up its better

Zee

Lol

Fargle

Well, sure, there's a middle ground. Don't be me, humblebragging yourself up on online chats. >_>

Daminark

Lolol

Zee

I actually think hubris is very important to make big discoveries

The downside is if you aren't a genius you will sound like me and fragle

Daminark

22:08

Why do I keep seeing the word "Genus"? I'm not even totally sure what that means

But yeah I mean, I'm definitely trying to get shaped up Laci-style, Hungarian mathematicians seem to just click with me best

Fargle

My biggest problem is that I seem to lack some underlying mathematical creativity. You seem to have that in spades.

Haha, I mean, look at baby Weil chapter 2. You and Balarka are like "lol ez" and I just, ow, it hurts my head.

Daminark

I didn't quite say that, I just got one exercise because I was trying to go for a very impolite solution that actually was in the right step

Maybe that's how I should approach math

"Ooh try this, it's abuse... Wait hold on crap..."

Fargle

lel, well, maybe.

I wish there were a way to acquire that creativity. And maybe hard work could do it. But a life of things being easy doesn't exactly prepare someone for hard work.

Daminark

This is true. I've mostly made it because of pregaming so far

Zee

That's bullshit, mathematical creativity is nothing more than mathematical maturity , self honesty and balls

Daminark

22:17

Like, I knew what was going on in part of Rudin before taking analysis so the beginning was aight

Fargle

@Zee Maybe so. The problem is, acquiring mathematical maturity takes work, and I don't have the human maturity to be okay with work.

Daminark

I'll say that most of mathematical discovery isn't really creativity so much as, there's a methodical way of thinking about something but when it's explained, that doesn't appear

But some stuff is just black magic

Zee

fragle, then work on doing work

Fargle

@Zee Here's the paradox: how does someone without self-discipline learn self-discipline through self-discipline?

Daminark

Easier said than done. I'm also ridiculously lazy, and breaking the disposition requires not having it

s.harp

22:21

just do work

eventually it will stop annoying you

Fargle

But belly-aching is so much easier!

s.harp

once that point has been reached you "have discipline"

Zee

Then your problem is not mathematics but self discipline

Fargle

Agreed.

Zee

Short of paying somebody to force you, I would suggest developing a routine, surrounding yourself with hard working people ...etc

Fargle

22:30

That's fair. I'm going to devote some time to actually doing that.

Bye chat.

Daminark

One way to start is to find something that gets you carried away, work in a group, and have a specific goal. I'm hoping NT does that for me

Anyway, see you

Adeek

22:48

hi @arctictern

hi everyone

hi @BalarkaSen

TheGreatDuck

0

Q: If a parametric surface is continuous, is it reasonable to expect that an integer grid will also be continuous?

This is somewhat of a follow-up to a previous question which asked in a roundabout way about how to walk upon a parametric surface approximated by triangular faces. Now I want to know is whether or not my proposed construction of the model itself will actually work in the way I imagine. Suppos...

algorithms surfaces parametric

im not sure if this is true, but if it were than it gives rise to the data structure I need to build my surfaces...

Adeek

0

Q: Proof verification: Zariski topology is quasi-compact

I am solving the following problem from AM commutative algebra. I am solving commutative algebra in my spare time to get good grip in it. Prove that the Zariski topology is Quasi-compact. Here is my proof, I just want to make sure that I have everything correct. We want to prove that X is quas...

algebraic-geometry commutative-algebra

@arctictern if you find sometime in your hand

Balarka Sen

@Fargle When I mean ez I mean I can't really do it

but also don't want to [smug face]

I know a lot of math but I can't really do really tricky, original things. That's my main qualm with myself.

anything i come up with is just a patch up of things i have seen before :(

idonutunderstand

23:16

Well knowing which things to patch up should give you some pride no?

Balarka Sen

I don't know if it should but it doesn't. I feel like I'm stealing ideas.

or just saying things which everybody knows already

Fargle

23:43

Well there's a sense in which no idea is original.

Human intelligence seems to be some kind of patchwork of analogies.

But, of course, that's Hofstadter's idea and not mine (heh).

Daminark

23:59

Kek @Fargle

Transcript for

$Mathematics$ Mathematics