/mg/ - Mathematics General Origami Edition

[Anonymous No.11788501]

Previously:>>11784117

[Anonymous No.11788503]

Is there graph theory involved in origami?

[Anonymous No.11788571]

Are the MAA book recommendations worth caring about?

[Anonymous No.11788718]

>>11788571
Yes, but probably not for your purposes. The BLL list is not saying "these books are really good, you should read them" they're saying "all academic libraries need to have a copy of these".

Also the MAA reviews themselves are generally not the best quality (Michael Berg has written a fucking bazillion reviews about books he's barely skimmed through because 80% of the review is always just some bizarre half-relevant boomer rant about BACK WEN I WUZ A GRAD STUDENT and then he makes a few entirely vague praises of the book).

[Anonymous No.11788736]

>>11788571
There is only one list worth caring about.

[Anonymous No.11788975]

>Be me, stuck in a school filled with algebrists and algebraic geometers,
>Ask the grad student advisor if there are any classes to broaden my mathematical background
>"I think someone's teaching an algebraic topology course in the spring"
>Fuck
>Turns out there's a graph theory course, normally not into discrete cs shit, but fuck it, I'll take it.
>Semester starts out easy enough, define a graph, learn about the matrix-tree theorem, no problem
>Actually start to enjoy learning about graph theory now, markov chains on graphs are pretty fuckin nice
>One day he introduces something called chip-firing on graphs
>Feels weird, but fuck it, probably building up to something cool
>"Well class, we defined chip firing so that we can study properties of divisor on graphs"
>I must've heard him wrong, cause there's no way he said divisors on graphs
>Suddenly he starts defining divisors and torsors on graphs
>"You see class, chip-firing allows us to prove the Riemann-Roch theorem for graphs"
>Ex-fucking-scues me?
>"We can also define Jacobians and theta functions on graphs as well."
>no
>"This will allow us to talk about the Abel-Jacobi map"
>No
>"Using this we can develop the classical Brill-Noether in the contexts of graphs"
>NO
>The zoom session starts glitching out, the teacher rapidly loses his hair and glasses materialize onto his face
>Hom functors and derived categories burst from my key board preventing me from exiting out.
>The ghost of Atiyah's credibility stops me from swallowing my tongue, while Fesenko watches and pretends he's doing something
>mfw the zoom session title changes
>mfw I was in a stealth algebraic geometry course this who time

[Anonymous No.11788992]

>>11788975
I want this turned into a horror movie.

[Anonymous No.11788998]

>>11788975
should have taken algebraic topology man

[Anonymous No.11789018]

>>11788975
lmao good post

[Anonymous No.11789182]

>>11788571
>open up the homological algebra category
>it recommends Hilton, Rotman, Maclane's Homology and Bourbaki
How do you plan on using a list that gives five books for each subject as recommendations? You'll eenie meenie one of the options?

[Anonymous No.11789300]

why did nobody tell me the cantor diagonal set is nonempty because the empty set must have a preimage dangit

[Anonymous No.11789358]

>>11788503
>origami
God damn /po/tards, shitting up every board!

[Anonymous No.11789361]

>>11789358
A pity that they will inevitably shit up this thread with discussion whether black or white origami paper is better...

[Anonymous No.11789364]

Are there any other joke videos like this one? Most math humor sucks ass but this is alright:
https://youtu.be/aewo8otGAAQ

[Anonymous No.11789378]

>>11788501
I know I've asked this question before and got the answer. However, I've forgotten it and am revisiting the project which requires the knowledge.

Given a system of m linear equations in n variables, with m < n, and given some point p not contained in the hyperspace defined by these equations, how can I calculate the point q in the hyperspace that is nearest to the point p?

Can someone please point me in the right direction?

[Anonymous No.11789381]

>>11789378
P.S. If I remember right, I know it requires calculation of the normal to the hyperspace, and then parameterizing this with respect to the point p. But I can't seem to find good information online about calculating this normal for general n and m.

Please help.

[Anonymous No.11789385]

>>11789381
what you're looking for is called the projection onto the subspace

[Anonymous No.11789388]

>>11789385
Thank you! Just to clarify, I am projecting the point onto the subspace defined by the equations? Or I'm projecting the equations onto the subspace defined by the point? Or is this distinction arbitrary?

[Anonymous No.11789398]

>>11789388
you are projecting the point (technically the vector) onto the subspace defined by the equations
projecting onto the subspace "defined by the point" would just give you some multiple of that vector, since a 1D subspace is just a line

[Anonymous No.11789401]

>>11789398
Beautiful, thank you

[Anonymous No.11789432]

>>11789364
https://www.youtube.com/watch?v=Q1IcXuK0FwE

[Anonymous No.11789441]

>>11789432
>>11789364
Sorry, wrong video, this one
https://www.youtube.com/watch?v=n12bfWTw9Hk

[Anonymous No.11789464]

>>11789182
>You'll eenie meenie one of the options?
Yes.

[Anonymous No.11789476]

>asking /mg/ about textbooks, instead of asking your advisor or professor or whoever
ngmi

[Anonymous No.11789492]

>>11788718
I understand. The reviews are my concern really. They do recommend books to students, make a point about stuff like self learning.
But then the reviewer has some random qualifications and it makes me doubt the whole thing.
>>11789182
I mean it's a start

[Anonymous No.11789508]

>>11789385
>>11789398
I hate to ask for more info, but everything online seems to discuss the orthogonal projection onto subspaces defined by points or other things. I can't seem to find the info about subspaces defined by a system of linear equations. Any resources I can look at?

[Anonymous No.11789524]

>>11789508
>but everything online seems to discuss the orthogonal projection onto subspaces defined by points or other things. I can't seem to find the info about subspaces defined by a system of linear equations.
they are the same thing
the "subspace defined by a system" is the subspace spanned by the solution vectors

[Anonymous No.11789535]

>>11789508
look up Moore-Penrose pseudoinverse. Ax = b, apply the pseudoinverse A* to both sides, get x = A*b. thusly defined x is not always a solution, but it's always at least the best approximation, i.e. the orthogonal projection you're looking for.
or you can solve the system to get a particular basis of the subspace. then there's an algorithm for computing the orthogonal projection onto a subspace spanned by set of vectors.

[Anonymous No.11789552]

Why do people actually ask for book recommendations?
I've always picked random shit, and I think the only times when I dropped a book and went to read something else was with Rudin's Functional Analysis, Daniel Bump's Lie Groups and Gelfand-Manin's Homological Algebra.

[Anonymous No.11789641]

Can I get an example of an Abelian group such that [math]x^2\neq1,\forall x\in G[/math]?

[Anonymous No.11789644]

>>11789324
>It uses the shitty mathJax, right?
You can use either
>If you are using AHK scripts you are RETARDED.
AHK is not optimal of course but its still better and faster than manually typing stuff and easier to setup than other methods. I would argue that you are probably the retarded one if you take so much time writing math on the computer.
>So you are just rereading/looking at the same set of cars over and over? That's extremely inefficient
Why did you start to seethe so much in this post and how is that answer you came up in your head do you not see that rereading and looking over and over at the same script is not efficient?
>I know what it covers and what theorems are in there, I don't need more.
Its not an answer to my statement but how do you actually know that you know that stuff? You have to go back to that big script, test yourself on your knowledge, and then look through it all and correct your mistakes, that's a lot of mental effort (and I'm not even including other stuff that also add to that effort) especially if you want to be thorough with it, while with Anki you will do that mental effort over time in a way more efficient manner since the algorithm will take care of what and when to show, you will see stuff that you had an easy time with at bigger and bigger intervals and stuff that you had a harder time with will be shown more often.

[Anonymous No.11789723]

Can someone give me a good reference of global/relative [math]\text{Spec}[/math]? That is [math]\text{Spec}(\mathcal F)[/math] for a quasicoherent algebra. I'm so lost lads...

[Anonymous No.11789747]

>>11789641
Z/3Z

[Anonymous No.11789773]

>>11789747
Much obliged.

[Anonymous No.11789780]

>>11789773
If you want something to do over the weekend, try to find an abelian group of even order with this property.

[Anonymous No.11789790]

>>11789780
rude

[Anonymous No.11789795]

>>11789780
Does that property hold for all congruence classes Z/mZ where m is odd or m = 3 a special case?

[Anonymous No.11789806]

>>11789795
he's trolling you. Look up Cauchy's theorem

[Anonymous No.11789808]

>>11789790
No u

>>11789795
For all odd, m=3 is the minimal case. Let's take for example m=9. If x^2=2x=0, then 2x is divisible by 9, and so it must be 18y for some y, and then it's already 0.

[Anonymous No.11789817]

>>11789641
Lagrange's theorem + Cauchy's theorem should solve this problem completely

[Anonymous No.11789907]

>>11788975
hello, basis department?

[Anonymous No.11789913]

>>11788975

[Anonymous No.11789996]

>>11789552
People who hoard books then never read them
People genuinely looking for a good first look
People who have shit books assigned to them and don't know better
People who want good self teaching books
>>11789476
Not an available option in some cases

[Anonymous No.11790184]

>>11789996
>People who hoard books then never read them
How do I stop doing this, /math/?

[Anonymous No.11790208]

What are the optimal colours for reading?

[Anonymous No.11790212]

>>11790208
Black on white.

[Anonymous No.11790213]

>>11790208
The colours of your lips and eyes, my love

[Anonymous No.11790241]

>>11789644
>You can use either
What the fuck does that mean?
What is "either".

>and easier to setup than other methods
Lol.

>I would argue that you are probably the retarded one if you take so much time writing math on the computer.
What do you mean? I do think I am reasonably fast.
Even if you were twice as fast as I am it would still be many hours.

>and looking over and over at the same script is not efficient?
But you are also looking at the same cards again and again. Anki isn't magic, you still have to learn.
What the fuck is your argument even?
I am seething because you fail to make a point which doesn't clearly appt to my method just as well...

>but how do you actually know that you know that stuff?

> Don't look at theorem. Do I know what it says y/n?
> Don't look at proof. Do I know how it works y/n?
> Don't look at definition. Do I know what it says and what some intuition behind it is y/n?

>and then look through it all
No. Why would I do that?

>you will see stuff that you had an easy time with at bigger and bigger intervals
Just like I don't read through a definition I know by heart 5 times in a row...
Fucking wow.
Not learning things you already know is trivially easy to do.

You can do the basic Anki algorithm completely in your head.

[Anonymous No.11790246]

>>11790208
White foreground black background.
Unless you are on a fucking computer screen which you should avoid at all cost...

[Anonymous No.11790258]

>>11790246
I feel white/black has too much contrast for my eyes. Some things I cant use something other than a computer. I can't read papers/online textbooks physical

[Anonymous No.11790277]

>>11790258
>I can't read papers/online textbooks physical
the most zoomer sentence ever put to text

[Anonymous No.11790279]

>>11790258
>I can't read papers/online textbooks physical
Man invented "printers" to solve this issue.

>I feel white/black has too much contrast for my eyes
Probably true on a computer screen. You might look at a couple of programming color schemes to get a few recommendations what people who professionally stare at computer screens use.

Also, as I mentioned in the other thread, your black arrows are probably a bug in your pdf viewer you should try a different want. Alternatively, my guess for the reason is that the anti-aliasing is fucking something up, fiddling around with that might work.

[Anonymous No.11790300]

It is well-known that every finite group is a subgroup of a symmetric group. However, is there anything known about the smallest symmetric group that a group G is a subgroup of?
Are there some interesting results in this direction?

[Anonymous No.11790339]

>>11790300
What is the highest order of any of the elements in your group? Find that, embed accordingly. You will notice that this is minimal because any smaller symmetric group would lack elements of that order.

[Anonymous No.11790385]

>>11790300
It seems like what you're asking is very hard outside of "nice" groups.
I've never seen this asked other than the classical "you can embed Q8 into S8 but not S7" question everybody does at some point so I googled around a bit and the stackexchange answers mostly just link to papers, so it's incompletely solved in general. This one has a nice summary of results though, including the abelian case, which is solved and has a pretty answer: https://math.stackexchange.com/questions/3362305/how-we-can-find-the-symmetric-group-with-least-n-whose-subgroup-of-it-is-isomo
and you can find lots more if you search around for stuff like "minimal permutation representation"

>>11790339
retard

[Anonymous No.11790394]

>>11790385
I know. It's obviously wrong.

[Anonymous No.11790419]

>>11790184
Read one instead of planning to read. The latter is just jacking off really

[Anonymous No.11790441]

>>11790279
I dont wanna dish out on a printer for the odd paper here and there, and dont have access to university stuff since its all shut down, and im not going to print a 500+ page online book. Also can't rent every book i want to reference from the library, especially if i just want a quick peak from libgen.

>your black arrows are probably a bug in your pdf viewer you should try a different want
i fixed the problem actually. There was an option exclusively for recolouring lines or not weirdly enough.

> few recommendations what people who professionally stare at computer screens use
will do, thanks

[Anonymous No.11790447]

>>11788503
Of course, first thing that comes to mind is maekawa's theorem which let's you determine if a given crease pattern is flat-foldable. I'm sure there's more though, an origami crease pattern is effectively just a graph.

[Anonymous No.11790488]

>>11790441
>and dont have access to university stuff since its all shut down
Right now, sure. But this isn't true in general.
Especially in the case of papers it is just so much better to just print them.
Books obviously are bigger, but usually I just need a couple of sections, so I just print those.
I also leech of the nice laser printer my dad has, so that makes the whole thing a bit easier in my case...

>There was an option exclusively for recolouring lines or not weirdly enough.
Quite weird, but if it works it works...

[Anonymous No.11790507]

Since you guys are so good at math, what is 9 + 10?

[Anonymous No.11790509]

>>11790507
about tree fiddy

[Anonymous No.11790562]

>>11790507
A unique solution exists in the real numbers.
Any other questions?

[Anonymous No.11790563]

>>11790507
a lot!

[Anonymous No.11790579]

>>11790562
Yes professor. I've managed to prove a lower bound (its at least 9) and an upper bound (21) for this equation, may i have permission to use the uni super computer to search for an exact solution?

[Anonymous No.11790581]

>>11790507
9 mod 10

[Anonymous No.11790587]

>>11790507
10 + 9, since addition is commutative.

[Anonymous No.11790588]

>>11790579
We should start by doing some research about more efficient algorithms to compute these "addition type" problems.
We should talk to numerical analysis experts in this department.

[Anonymous No.11790589]

>>11790339
>>11790563
>>11790587

[Anonymous No.11790658]

>>11790588
This is the algorithm I have created. I reckon it should only take about six hours of computation to find the solution to 9 + 10

[Anonymous No.11790660]

>>11790658
Great work!
But maybe we can parallelize this, else even a super computer will be no use...

[Anonymous No.11790681]

>>11790588
Don't bother, the halting problem is provably turing reducible to epsilon-approximation algorithms for this computation task. It's highly undecidable and it seems likely that a concrete answer would imply a positive answer to the continuum hypothesis.

[Anonymous No.11790724]

>>11790589
I am beyond criticism. I am above law.

[Anonymous No.11790735]

>>11789723
bump

[Anonymous No.11790739]

What would happen if I jumped straight into riemannian geometry without knowing the prerequisites?

[Anonymous No.11790747]

>>11790739
It would be extremely painful.

[Anonymous No.11790750]

>>11790739
you would be LARP’ing

[Anonymous No.11790761]

>>11790739
nothing, you would just waste time

[Anonymous No.11790765]

>>11790739
What do you mean by "Riemannian geometry?"
What do you mean by "prerequisites?"
Do you know what a manifold is?

[Anonymous No.11790772]

>>11790739
You could look at it the same way I look at some fancy algebraic text and think "wow this is some next level typesetting", although the "wow" would be replaced by "blergh" and you would most likely feel horribly stupid for wasting your time like that.

[Anonymous No.11790794]

>>11790739
The devil is gonna rise up from the ground and kill you for trying to learn a subject without knowing the prerequisites.

[Anonymous No.11790822]

>>11790739
You will read the text but understand nothing.
It's literally pointless.

[Anonymous No.11790847]

Is trying to grasp Lie theory as an undergrad a fruitless attempt?

[Anonymous No.11790848]

Is it possible to master algebraic topology in 1 year and a half if I'm just starting abstract algebra now?

[Anonymous No.11790851]

>>11790847
No.

[Anonymous No.11790853]

Does /mg/ smoke?

[Anonymous No.11790860]

>>11790853
7 a day generally

[Anonymous No.11790872]

>>11790860
7 is quite a lot. Do you find that it helps you with doing maths?
I really like smoking, it clears my mind and gives a really pleasant feeling but I'm afraid of its health benefits so what I do is I smoke for 3 months about 1-2 cigs a day and then break it for 3 months. Repeat.

[Anonymous No.11790881]

>>11790872
>Do you find that it helps you with doing maths?
No man it's just escapism, drop that shit asap, my grandad died because of it

[Anonymous No.11790892]

>>11790847
Just focus on concrete examples to start with, namely matrix groups and their commutators. If you have no examples under your belt then churning through the abstractions is going to be very painful and not informative.

[Anonymous No.11790906]

>>11790853
No.

[Anonymous No.11790907]

>>11790881
>drop that shit asap
I haven't smoked in over 3 months now. I would like to start smoking again because it feels very good and keeps my brain alert but I don't want to ruin my lungs because I've been jogging for the past month with high intensity and it requires healthy lungs. Smoking makes running much harder. The hypothesis is that jogging is better than smoking for your brain.

[Anonymous No.11790913]

>>11790853
I only drink and drunk post.

[Anonymous No.11790943]

>>11790907
Nothing is "good" for the brain, you won't develop a higher IQ because you're jogging or smoking, stop deluding yourself, you were born with an IQ number and during childhood that number might have gone up or remained the same depending on which education your parents gave you. There's no changing it now, just deal with it and move on, all that's left now is to play the game with the cards you've been dealt with.

Also, pills, food, games or whatever is trending these days will not make you magically better at math, the ONLY thing that will make you better at math is, SURPRISEEEE, studying math!

[Anonymous No.11790944]

>>11790853
I don't smoke mostly because of the smell. The feeling you get from smoking is very nice but if you smoke on a daily basis you and everything you own smells like shit and turns yellow

[Anonymous No.11790946]

bros... i don't feel like anything...

[Anonymous No.11790952]

>>11790944
I actually like the smell of smoke and cigarettes when smoking or when going by others who smoke, but the residue on my fingers does smell awful.
When you're drunk though, the smell is the best smell in the world.

[Anonymous No.11790976]

People should honestly stop associating Steins;Gate with /sci/ and /mg/, it's problematic, why? Because it's no different than the bullshit sprout by Neil DeGrasse or Numberphile, it's pseudo-science at its finest, normie-bait without any real meaning or deepness into it, they just throw out concepts they've learned in a 15 minute video without any mathematical formula, threw some waifus in it and made a nonsensical story. It's especially funny when people post Kurisu solving math problems here when she's a bloody "neuroscientist" (which gets called to give a lecture on time travel in a university for some reason kek), just proof that those people have no idea of the harm they're doing when they associate such garbage with /sci/ and /mg/.

[Anonymous No.11790979]

>>11790976
Why do we hate Numerphile, again?

[Anonymous No.11790980]

>>11790976
it's okay when Japan does it

[Anonymous No.11790985]

>>11790979
normal people like it so you're not allowed to

[Anonymous No.11790988]

>>11790976
>those people have no idea of the harm they're doing when they associate such garbage with /sci/ and /mg/
I didn't know we were important.

[Anonymous No.11790989]

>>11790976
In the show Kurisu is a polymath who also studies physics. It's zany sci-fi but the story is coherent and they even make use of 2channel.

[Anonymous No.11791005]

>>11790988
>I didn't know we were important.
I just don't want the community I choose to post in become a laughing stock in other math-based communities like physicsforum or mathstack exchange.
>>11790989
No matter how intelligent she is, in this day and age you can't specialize yourself in two different areas of knowledge. The story is not coherent, I noticed some plotholes, but I do concede that the characters are well made. It's just that, pseudo-science should never be beloved or accepted on /sci/, that's all.

[Anonymous No.11791011]

>>11791005
>caring this hard what other people think
It's an anime imageboard turned science forum. It could not matter less what the «public perception» of this place is. (Protip: no one even knows it exists.) Come back when you're not underage.

[Anonymous No.11791018]

>>11791005
Assuming you are seriously taking the social standing associated to these forums so seriously, maybe you should leave this site and never come back. Bye bye.

[Anonymous No.11791020]

>>11791011
>no one even knows it exists.
There's an anon from here who was cited in a proof.

[Anonymous No.11791031]

If G is all reals under addition and H is all positive reals under multiplication, is exp(x) the only isomorphism between them?

[Anonymous No.11791033]

>>11791011
>>11791018
Yeah, let /mg/ become a laughing stock to everyone else in the math community, nothing wrong with that...
>>11791020
Not the best example since it took years until anyone found his post, but /mg/ and /sci/ are frequented by high level mathematicians and physicists, like Misha, it's not just "le useless anime imageboard" like some people here want to paint it as.

[Anonymous No.11791044]

>>11791031
No.

[Anonymous No.11791046]

>>11791033
It's nou useless, you're just scum. It doesn't matter if some faggot like you comes along and spews a bunch of trash. No ones cares. No one sits around debating the merits of /sci/ or stackexchange or wikipedia. They get what they need, post what they want, and move on.

[Anonymous No.11791048]

>>11791005

Scrawny highschooler:

> It's just that, pseudo-science should never be beloved or accepted on /sci/, that's all.

Genius scholar who is fucking ripped:

> The industrial revolution and its consequences have been a disaster for the human race.

[Anonymous No.11791051]

>>11791048
you have to go back

[Anonymous No.11791055]

>>11791031
a^x for any a>1 is OK.

>>11791033
>nothing wrong with that
Hey we agree! How cool is that?

[Anonymous No.11791061]

There's nothing wrong with animeposters.

[Anonymous No.11791063]

>>11791061
but there is with being a tranny retard, which describes most of them in this thread

[Anonymous No.11791064]

>>11791061
There's a lot wrong with me.

[Anonymous No.11791075]

>>11791063
That's what you have to put up with if you're gonna do math. It's still not as bad as CS. I hear Google is just flush with them.

[Anonymous No.11791085]

>>11791075
>if you're going to do math
>he thinks I would ever waste my brain on fake and gay abstractions like pure math
kek

[Anonymous No.11791087]

>>11791046
>>11791055
How am I scum? You realize your insults mean nothing to me if you're just throwing them out in the air without even justifying them, right? Just makes you look pathetic. You hold far too simplistic views on how a community should work, why do you think /sci/ has attracted world famous scientists and mathematicians until now? Why do you think someone here managed to solve a 20 year old problem in combinatorics? Those people are attracted by the reputation that /sci/ has among other communities, keep associating /sci/ with pseudo-science garbage like Steins;Gate and Numberphile and you will soon see the community that once had high level discussions attract people that are only interested in fantasy shit.
https://www.reddit.com/r/math/comments/1rkc0r/found_this_on_4chan_what_do_you_think/
Are you really ok with being humiliated like that by fucking reddit? If so, then you're the scum here.

[Anonymous No.11791096]

>>11791087
r/math is unironically pretty good, though.

[Anonymous No.11791101]

>>11791087
>why do you think /sci/ has attracted world famous scientists and mathematicians until now?

They're a bunch of spergs who jerk it to traps on /b/.

>Why do you think someone here managed to solve a 20 year old problem in combinatorics?

Autism, skill, whatever.

>Are you really ok with being humiliated like that by fucking reddit?

Go back. I don't have any interest in Reddit.

[Anonymous No.11791104]

>>11791096
Name one world famous mathematician posting there.
Name one unsolved problem solved by them.

Their reputation is far below /sci/'s, although it might change soon since brainlets here keep pushing pseudo-science shit.

[Anonymous No.11791105]

>>11791087
>reddit post from 6 years ago with 0 upvotes
Truly humiliating, there really is no recovery from this, I believe it is time to shut down 4channel forever.

[Anonymous No.11791106]

>>11791087
I wish you could point one single insult I threw at you. Obviously, you can't.
>why do you think /sci/ has attracted world famous scientists and mathematicians until now?
Couldn't care the less.
>Are you really ok with being humiliated like that by fucking reddit?
I'm OK with being targeted by foul words if I don't see them myself. It tells something about where you should probably go to if you are so sensitive: Reddit. Bye bye, anon.

[Anonymous No.11791110]

>>11790587
What anime is this from?

[Anonymous No.11791111]

I post anime and I'm not a tranny.

[Anonymous No.11791113]

I honestly can't tell if this guy is serious or not.

[Anonymous No.11791115]

>>11791110
https://myanimelist.net/anime/32607/Giarlish_Number

[Anonymous No.11791117]

>>11791111
Nice quads, I'm a tranny and I don't post anime.

[Anonymous No.11791118]

>>11791111
You just contradicted yourself.

[Anonymous No.11791124]

>>11791115
>6.91
Must be pretty bad if MAL of all places rated it so low.

[Anonymous No.11791130]

>>11791115
Thank you very much anon.

[Anonymous No.11791131]

>>11789641
No such group exists, since [math]1^2=1[/math]

[Anonymous No.11791133]

>>11791106
Well, if you want me out so much, just ban me, bitch, I know you're a mod, I'm not scared of you, I'll just come back, so go on, ban me, you fucking jerk

[Anonymous No.11791140]

>>11790208
>>11790882

[Anonymous No.11791145]

>>11791124
I don't know why it's so low. I liked it.

>>11791130
You're most welcome.

>>11791133
Quite rude.

[Anonymous No.11791148]

>>11790848
master? no
Learn the basics? YES

>>11790853
no

[Anonymous No.11791154]

>>11791124
i'm not really a gigantic fan either, i'd say it was nothing special but alright
it just happens that i found a batch of reaction images from that anime

[Anonymous No.11791170]

>>11791148
>master? no
>Learn the basics? YES
Is it possible to do 8 courses in one semester? I'm average and failed some classes, so I need to do that if I want to graduate in one year, what do you think?
Also consider that classes will probably be online this semester.

[Anonymous No.11791175]

>>11791170
>Is it possible to do 8 courses in one semester?
Yes
>I'm average
no

[Anonymous No.11791194]

>>11791170
Depends on you. Some people can do that, but if you've already failed some, unless you go full military regiment and hunker down, you're playing with fire. If you decide to do it, spread out the types of courses if possible, i.e. don't take 4 proof classes at the same time, take like odes/pdes or graph theory or something with them. Good luck!

[Anonymous No.11791196]

>>11791175
Well, fuck you then, I'm gonna do it whether you like it or not

[Anonymous No.11791203]

>>11791196
Why bother asking then?

[Anonymous No.11791208]

>>11791203
so he can do it out of spite

[Anonymous No.11791210]

>>11791194
>tfw you'll never study math sitting on the floor in a comfy japanese room with your japanese mates
You're right, I'll do analysis, algebra, multivariable calculus, ode, statistics, numerical analysis and mechanics next semester then, what do you think?

[Anonymous No.11791214]

>>11791170
>Is it possible to do 8 courses in one semester? I'm average and failed some classes
I did that with 5 or 6 and I think my GPA ended up being like 2.3/5 after that. I don't recommend it, but it's possible.

[Anonymous No.11791217]

Is combinatorics an interesting subject? Thinking about taking it next semester.

[Anonymous No.11791219]

>>11791217
If you are a CS fag yes, everything gay and ugly is interesting.

[Anonymous No.11791224]

>>11791217
Don't listen to that other poster, a lot of beautiful math from different branches meets in combinatorics.

[Anonymous No.11791228]

>>11791210
Not sure what you mean by mechanics, quantum, classical? (or not physics?) Odes and num. anal. should be pretty easy (stats too if it's just an intro), that's about as good as a spread as you can get.

>>11791217
Yes, but the problems can become very dumb/unintuitive with just little tweaks. I've heard some people say that it's 50% a math course and 50% a language one.

[Anonymous No.11791246]

>>11791228
>Not sure what you mean by mechanics, quantum, classical? (or not physics?)
Classical
>Odes and num. anal. should be pretty easy (stats too if it's just an intro), that's about as good as a spread as you can get.
I see, I'll do it then, thanks.

[Anonymous No.11791257]

Is there a combinatorics savant in history like ramunajan was to sums?

[Anonymous No.11791261]

>>11790507
10.999999....

[Anonymous No.11791267]

>>11791087

lmao.

>>11791257

ramanujan

[Anonymous No.11791271]

>>11791257
Erdős, obviously.

[Anonymous No.11791273]

>>11791257
Terence Tao

[Anonymous No.11791281]

>>11791257
Quite a bit of the stuff Ramanujan did was (at least partially) combinatorics. He proved a lot of partition identities.

It's hard to describe people "like Ramanujan" because there aren't that many mathematicians who are famous for pulling ridiculous theorems out of their asses in any field. Erdos was certainly a combinatorial savant but he was just incredibly clever and technically skilled. His stuff doesn't look like it came from the moon.

[Anonymous No.11791296]

>>11791257
MacMahon
Szemeredi

[Anonymous No.11791306]

>>11791224
and nothing beautiful will ever come from combinatorics or discrete math

[Anonymous No.11791315]

I did math for the whole waking time today. Had a break for eating and 30 min excercise.
It felt great. I went over 3 hours my regular fall asleep time. Probably gonna continue that for the next day, no uni assignments until end of next week. That feels NICE. I dont remember being that hopefull bros.

[Anonymous No.11791322]

>>11791281

That's what it takes to shake any field in modern math, you have to be completely obsessed with a concept, be creative AND have the raw brainpower to tie it all together. The bar is getting so high soon only 3 people on earth and supercomputers will be able to contribute to math.

[Anonymous No.11791334]

>>11791322
>supercomputers
Heh, you've been watching too much "science" on youtube, kiddo.

[Anonymous No.11791344]

>>11791322
>The bar is getting so high soon only 3 people on earth and supercomputers will be able to contribute to math.
Maths is best when approached as a hobby and contributions as a side product of doing stuff you like. Computers shut down when you press the power button, but hobbyists remain until they have been killed.

[Anonymous No.11791360]

>>11791344
>Maths is best when approached as a hobby
Exactly, thanks. That's why foundations is the best area, it's fun, it's highly complex and it mix philosophy into math, the other areas are just glorified puzzle games.

[Anonymous No.11791371]

>>11791334

Why? if you can't prove anything with logic the only other way to further math would be using brute force with "supercomputers" aka just a way to say a lot of processing power

[Anonymous No.11791402]

I can't be the only who autistically copies textbook in notebooks with my own formatting, completing the proofs, and adding comments in the margin and in pencil ("can find more examples of this theorem in book x")

been doing it since ~2 years now and completely completed a good dozen of them

[Anonymous No.11791411]

>>11791360
You're welcome. I'll let you play with the foundations, I want my glorified puzzles.

[Anonymous No.11791455]

>>11791371
It will take centuries until computers reach that level, also you're not taking into account the artistic aspect of math, just the logical ones. Sure, in the far distant future computers will be able to prove all sorts of theorems, but they won't be able to discover new areas all by themselves or create new definitions and axioms.

[Anonymous No.11791458]

>>11791411
Wow, rude, no need to be offended man.

[Anonymous No.11791479]

>>11791458
Literally no idea what you are talking about, other than the wow. I am dazzling and I know it.

[Anonymous No.11791491]

>>11791402
based but bluepilled
>>11791360
low iq and redditpilled

[Anonymous No.11791505]

>>11791491
what would be based AND redpilled then

[Anonymous No.11791523]

>>11791479
You were clearly offended by my statement, so much so that you felt the need to use my description in an ironic way. Let's just agree to disagree bro, no need for hard feelings here.

[Anonymous No.11791538]

This is probably a low IQ question, but are there any groups where the binary operator is subtraction?

[Anonymous No.11791546]

>>11791523
Did I now? Did you know Bourbaki isn't a person?

>>11791538
No. a-(b-c)=a-b+c while (a-b)-c=a-b-c, and so it's not associative.

[Anonymous No.11791550]

>>11791538
I think that would be your original group, except that now x is -x and so on. But >>11791546 posted an anime face which means his statement is a lot more correct.

[Anonymous No.11791555]

>>11791096
/r/math is more toxic than /sci/ IMO.

[Anonymous No.11791566]

>>11791550
Well, there is the case where the group is just a bunch of copies of [math]\mathbb{Z}/2\mathbb{Z}[/math], as then + and - coincide.

[Anonymous No.11791567]

>>11791546
>Did you know Bourbaki isn't a person?
Glad you still remember the lecture I gave you.

[Anonymous No.11791574]

>>11791566
Yeah, I didn't consider associativity. Funnily, the question anon asked is in fact true for multiplication/division and I assume for a non-commutative group law.

[Anonymous No.11791576]

>>11791538
(0,-)

[Anonymous No.11791593]

>>11791567
Your feeble provocation attempts are too recognizable.

>>11791574
You sure? a/(b/c) = (ac)/b & (a/b)/c = a/(bc), or am I misinterpreting your post?

>>11791576
Is >>11791566 with 0 copies.

Anyhow, nighty night~

[Anonymous No.11791644]

>>11791566
Pretty sure that's the only case.
[math]a^2=e[/math], is implied by "subtraction" for every [math]a[/math].
Then, [math]e=(ab)^2=(ab)ab=(ab)b^{-1} a^{-1} =(ab)ba[/math] implies you have an abelian group where every element has order two.
So it's a [math]Z_2[/math] vector space.

[Anonymous No.11791646]

so guys, did you make any progress on IUT yet?

[Anonymous No.11791648]

>>11791593
Night, anon.

[Anonymous No.11791652]

>>11791644
Let me redact that commutativity proof.
[math]ab=(ab)^{-1}=b^{-1}a^{-1}=ba[/math]

[Anonymous No.11791665]

>>11791652
>[math]ab=(ab)^{-1}=b^{-1}a^{-1}=ba[/math]
Don't you hate when that happens?

[Anonymous No.11791670]

What would happen if I tried learning real analysis without knowing calculus?

[Anonymous No.11791676]

>try a method
>it was circular reasoning

[Anonymous No.11791677]

>>11791665
Yes.
>>11791670
See >>11790794

[Anonymous No.11791679]

>>11791670
>What would happen if I tried learning how to pilot a helicopter without knowing anything about a helicopter

[Anonymous No.11791683]

You have ten (10) seconds to name a non-abelian Lie group.

[Anonymous No.11791736]

>>11791670
Real Analysis is essentially Calculus from a proof based perspective. So you should be fine if your IQ>120.

[Anonymous No.11791740]

>>11791683
the complexes

[Anonymous No.11791817]

>>11791683
rotation

[Anonymous No.11791859]

>>11788975
Good post anon fuck algebraic geometers.

[Anonymous No.11791952]

Is there a specific term for the resulting matrix by taking a complex matrix and taking its transpose, then take each entry's conjugate?

[Anonymous No.11791978]

>>11791952
[math] A [/math]

[Anonymous No.11792026]

>>11791952
It's called lots of things. Simply calling it the conjugate transpose is what I've heard the most but you also see Hermitian transpose, Hermitian conjugate, Hermitian adjoint or just adjoint popping around in various contexts. Adjoint tends to be more in functional analysis where you're talking about more general operators than matrices.

[Anonymous No.11792050]

OK guys tell me how far are we from solving the Collatz conjecture? It seems so enticing, like a whole field of math just waiting to happen. You can change up the rules however you want, and different rule-sets give different cycles. It's just given a function from the naturals to the naturals, how does the sequence look? You number theorists better be working on this.

[Anonymous No.11792051]

>>11792026
Thanks.
It's something I see a lot, but it just dawned on me that I didn't know any sort of formal name for it.

[Anonymous No.11792056]

>>11792050
>OK guys tell me how far are we from solving the Collatz conjecture?
idk
>You number theorists better be working on this
y e s I a m (not really number theory tho it's more dynamical systems technically)

[Anonymous No.11792058]

Redpill me on the langpill

[Anonymous No.11792063]

>>11792058
I'm only familiar with his book on elliptic functions. What I can tell you that is it was a very dense book and pretty challenging to read. Not sure if all of his stuff is like that.

[Anonymous No.11792101]

>>11792063
I'm familiar with his algebra book and found it dense as fuck as well, not for a beginner at all.

[Anonymous No.11792126]

>>11792101

>not for a beginner at all

but undergraduates are beginners

[Anonymous No.11792187]

>>11788501
What are the differences and respective pros and cons bewtween taking an application as binary relation or as ordered triple (Domain, Codomain, Binary relation)

[Anonymous No.11792213]

>>11792058
read to achieve PhD in the inverse function theorem

[Anonymous No.11792273]

>>11792058
>>11792063
Lang was a diehard Bourbakist. All his stuff is written exactly the same way.
His algebra book has been, and still is, extremely commonly used in the first year of grad school for decades for a few reasons. When it first released in the 60s, there was just literally nothing comparable to it in coverage. You had to use it. Plus in pre-Internet days it was the best reference text bar none.
Nowadays there are many competing multi-purpose fatass algebra bibles (e.g. Aluffi, Rotman, Dummit/Foote) but as far as I know, all of the alternatives suffer from having kind of blah, too-easy problems. Say what you will about Lang's exposition, but the problem sets are excellent. Much like Rudin, it sticks around because of good problems and because standardization is nice.

I also unironically think his real and functional/complex analysis textbooks are excellent, although they're still in the same formalist style.
Most graduate analysis textbooks are written by analysts who are in love with analysis. Lang was a pretentious elitist algebraist, so his analysis books are "here's all the stuff a non-analyst might ever need and nothing else in one convenient yellow box". That's not an easy thing to find elsewhere.

[Anonymous No.11792286]

>>11792273
>specialized grad text is written by specialists
>you shouldn't learn the thing from those who are actually adept at using it
Why would you do this? Why would I read a book on algebra from someone who isn't an algebraist?

[Anonymous No.11792298]

>>11792286
Why would you think you need a specialist to teach you basic shit that everybody knows? Did you picket your linear algebra I class until they brought in a representation theorist to teach it?

You'd do it for the reason I posted; they're very accurately targeted to the analysis needs of people who aren't going to become analysts.

[Anonymous No.11792316]

>>11792273
>Bourbaki
Not a person.

[Anonymous No.11792328]

>>11792316
>Not a person.
That's a little insulting.
https://en.wikipedia.org/wiki/Charles-Denis_Bourbaki

[Anonymous No.11792542]

>>11791402
yes.

[Anonymous No.11792549]

>>11792298
I only take classes/read textbooks from people that are experts in the sub-field they're teaching or have a significant amount of training with that topic. I would never let someone who doesn't have some degree of mastery in technical field in math or science teach me even the most basic concepts unless I had personal experience with them prior to being taught. Anyone who would accept anything less is a cuck.

[Anonymous No.11792550]

What conjectures will advance technology once proven?

[Anonymous No.11792565]

>>11792550
Goldbach and Riemann

[Anonymous No.11792568]

>>11788501
I want to study math, but I also with to be employed. All math B.Sc end up being software engineers. If I'm going to be coding, I might as well take CS instead of math.

What kind of jobs can I find with a B.Sc in mathematics from a respectable university? What does /mg/ think of applied mathematics?
im canadian, if that matters at all

[Anonymous No.11792573]

>>11792568
>i'm canadian if that matters at all
It matters a great deal actually >>>/lgbt/

[Anonymous No.11792590]

>>11792568
Actuary, cryptologist, data scientist.

[Anonymous No.11792592]

>>11792573
i am now reflecting on the fact that i am asking 4chan advice

do people on this forum even study mathematics, or is it all just larping? there was a thread that asked people to prove: 1 = 0.9999999999... after more than 100 replies, no one could answer it. isn't this something you would mention in analysis 1? a first semester class for math majors?

[Anonymous No.11792605]

>>11792568
StatsCan hires fucktons of math majors each year. Very cushy government desk job. Other businesses hire statisticians too, although more and more nowadays they're called "data scientists" which is just a fancy term for a statistician who read a Python book
CSIS hires mathematicians for cryptography, although I don't know how many people without graduate degrees they take. Security screening is, as you can probably imagine, a gigantic pain in the dick and takes forever.
All major banks take mathematicians, but you will be locked out of the sexy quant jobs without at least a Master's.
You can teach. High school math teacher is really a decent job if you have the temperament for it.
Actuarial work is a very common choice if soul-crushing tedium in exchange for a comfy desk job with a nice salary sounds like a good trade to you. Also actuarial work is highly localized, you're essentially stuck in Toronto in Canada.

I won't pretend to be able to tell you anything about applied math jobs, since applied math is for fags.

[Anonymous No.11792606]

>>11792592
you need to go back >>>/r/eddit

[Anonymous No.11792609]

>>11792606

[Anonymous No.11792612]

>>11792609
>nu-chan fag memes
You won't ever be welcome here

[Anonymous No.11792623]

>>11792612
Well, I'm here to stay.

[Anonymous No.11792683]

A mighty fine morning, /mg/

>>11791644
It generalises to [math]\sum_{j \in \mathscr{J}} \mathbb{Z}/2\mathbb{Z}[/math], for any index set [math]\mathscr{J}[/math] (empty set gives you the trivial group), where the operation is defined coordinate-wise. As you mentioned, there are no other non-trivial examples. In general, the answer is still "no" when one is trying to get a subtraction group like >>11791538. Ironically, I was using the fact that there are no exterior algebras over [math]\mathbb{F}_2[/math] just a couple of hours earlier, and then I forgot the whole thing. A good reminder of why my posts should be discarded as rubbish.

[Anonymous No.11792721]

>>11792286
For the same reason some physicists cope with "Mathematical (((Methods)))" or things like that. Saves time and present things in a way that is familiar to them so they can benefit from it the most.

With an infinite amount of time, I would to read the whole Springer Collection again and again until I have a perfect retention of every single book, knowing what each author likes and why they present things that way. But a lifetime wouldn't be enough for that.

[Anonymous No.11792722]

>>11792683
What kinda fucked up time does this canadian cunt wake up at
Maybe the real reason you're potatoing isn't because you're over 24, but rather because you go to sleep before the real productive late night hours.

[Anonymous No.11792729]

>>11792722
>What kinda fucked up time does this canadian cunt wake up at
Way too late, to be honest. I would have wanted to wake up at maybe 7 or 8 o'clock, but it was 9. I didn't know I was Canadian.
>because you go to sleep before the real productive late night hours
Nay, I got sleep at maybe 2 o'clock. The "productive late night hours" are pretty much ruined by the fact that I am somewhat drunk 4-5 nights a week.

[Anonymous No.11792735]

Good morning math general!
>>11792729
>I am somewhat drunk 4-5 nights a week.
please take care of yourself...

[Anonymous No.11792741]

>>11792592
>do people on this forum even study mathematics, or is it all just larping?
I would guess that a few dozen people here are studying for a Bsc one or two dozen for a Masters and maybe a couple of people are PhD students.

>after more than 100 replies, no one could answer it.
Because that is literally just people trolling each other.

>isn't this something you would mention in analysis 1? a first semester class for math majors?
Sure. But these people are trolling. Obviously it is *literally* just the definition of real numbers.

[Anonymous No.11792749]

>>11792735
Morning & have a nice day + remember to stay hydrated if it's hot there! Planning to have a productive day or a free one?
>please take care of yourself...
Trying to. I reached some sort of katharsis and it feels like I'm regaining some motivation, so maybe I can drop a night or two.

[Anonymous No.11792954]

How to pronounce Lebesgue?

[Anonymous No.11792960]

>>11792954
Le-Beg

[Anonymous No.11792966]

>>11792954
Le Beg

[Anonymous No.11793015]

>>11792954
lil beck

[Anonymous No.11793023]

bros... I don't do maths... but I love all of you...

[Anonymous No.11793030]

>>11792954
Leh Bes Guh Eh

Fuck the Frogs and their disgusting language.

[Anonymous No.11793112]

>>11792954
It's Lebesque

[Anonymous No.11793167]

>>11793112
It's Lebesgue (better to remain silent and be thought a fool than to speak and to remove all doubt.)
https://en.wikipedia.org/wiki/Henri_Lebesgue
https://en.wikipedia.org/wiki/Morvan_Lebesque
>>11792954
le-BEG (stress last syllabe)

[Anonymous No.11793212]

>>11793167
All syllables are equally stressed in French.

[Anonymous No.11793223]

The concept of Entropy is such an eye opener for understanding probability distributions.

Like, Uniform(a, b) is the distribution with maximum entropy when you consider distributions with support [a, b]

And the Normal(μ, σ^2) is the distribution with maximum entropy when you consider distributions that have a mean and a variance equal to μ and σ^2.

So, that's why Normal is so ubiquitous. It's the distribution that assumes the "least". in the same sense that Uniform does.

https://en.wikipedia.org/wiki/Maximum_entropy_probability_distribution

Thanks for reading my blog.

[Anonymous No.11793224]

Nash's theorem for (finite) general-sum games states that each such game admits a Nash equilibrium. The proof I'm familiar with goes through Brouwer's FPT, which of course is non-constructive.

Given an arbitrary game, can one prove the existence of a Nash equilibrium constructively? I'm asking because there are bi-matrix game solvers abundant online, so it seems like there's a feasible algorithm for the problem; I know that for the special case of zero games, solving the game simply reduces to LP, which of course is computationally solvable. But is the problem of finding a Nash equilibrium in a general-sum [math]n[/math] player game even decidable?

[Anonymous No.11793232]

>>11792954
Leh-bes-ghe, obviously.
What, do you think french is some meme like english, where they add letters that don't represent any sounds?
>>11792960
This but the g isn't a hard g, it's a gh thingy. Not sure if english has the phonem.

[Anonymous No.11793240]

>>11793223
To add on to your blog, you may also consider where it came from in the first place, ie physics.

In statistical physics, maximum entropy is the natural state of things. And the natural state of things is the most isotropic and symmetric possible.
Without any external constraint, this means uniform distribution. ("microcannonical" distribution)
With an external constraint of temperature, this means normal distribution with the [math]\mu[/math] being the temperature and [math]\sigma[/math] being the uncertainty on the temperature.

IIRC, Boltzmann derived all that from symmetrical and geometrical considerations, intuitively using the idea that Nature is inherently isotropic, without using any fancy tools from functional analysis, topology, or measure theory to build the formalism.
This was actually one of the main criticisms of the theory at the time. It relied mostly on intuitions and "dude trust me" because the mathematical tools to prove it didn't exist yet.

[Anonymous No.11793268]

>>11793232
>This but the g isn't a hard g, it's a gh thingy. Not sure if english has the phonem.

Never read anything that retarded. Instead of boasting about the length of your mathematical dick, you should rather learn the IPA.

FYI, it's /lə'bɛg/.

[Anonymous No.11793281]

So there's the conic sections for quadratic equations of two variables. Of course there's also similar shapes by considering quadratic equations of three variables. Are these too "sections" of something? If so, what? Also, does this generalize to higher dimensions?

[Anonymous No.11793291]

>It's hard to know where to start with “baby Rudin.” There is probably no more well known, respected, loved, hated, and feared text in all of mathematical academia. Steven G. Krantz claims it’s one of the books that made him a mathematician; “It was easy to say, and often true, that anyone who could survive a year of Rudin was a real mathematician.” Vladimir Arnold, one of the champions of the “organic” approach to mathematics, reportedly called the book (in comparison to the lectures of Vladimir Zorich) “Bourbakian propaganda, stripping and sterilizing analysis of any soul or meaning beyond the symbols.”

>“Bourbakian propaganda, stripping and sterilizing analysis of any soul or meaning beyond the symbols.”

Who was in the right?

[Anonymous No.11793304]

>>11793291
My 2 cents is
I am currently reading it. I started out programming so I am inclined for symbolic manipulation. The approach is not too unlike a programming manual. It is dense, but readable. The point-set approach pretty much ensures it's self-contained and followable.
It lacks geometric or otherwise sensory intuition, which one has to fill in oneself.
I am inclined for the first, as long as one keeps in mind it is kind of 'legalese', pretty much pure technique, mostly distilled of substance. Great training, but not at all the whole story.
I'm reading it along Visual Complex Analysis. Provides the meat for those bones

[Anonymous No.11793307]

Is there a better feeling than seeing that blank page between the end of a chapter and the start of a new one?

Also, death to "This page intentionally left blank". I hate that, it makes no sense. It should say: "This page otherwise left intentionally left blank".

[Anonymous No.11793315]

>>11793291
Symbol pushing should always be criticized, even when it's logically "complete". Intuition should lead rigor, they both enhance each other, like how good songs in a musical enhance the plot, and a good plot lays the foundations for having meaningful songs.

[Anonymous No.11793317]

>>11793307
>"This page otherwise left intentionally left blank".
FUCK
I meant, of course,
"This page otherwise left intentionally blank".

[Anonymous No.11793321]

>>11793281
They are sections of more complicated surfaces.
There's also the broader family of polynomials of maximum degree m in n variables.

[Anonymous No.11793322]

Guys, what happens if I try to study vertex operator algebras without being homosexual?

[Anonymous No.11793359]

>>11793281
They are also conic sections, but with higher dimensional cones

[Anonymous No.11793365]

>>11792954
French speaker here, you do not have our "e" sound, so it is impronounceable to you, but it is something like Leh Beg

[Anonymous No.11793373]

>>11792954
lee bes kway

[Anonymous No.11793383]

>>11792549
Do you realize how much of a power gap there is between whatever class you have freshman year of college and what mathematicians actually do ? Do you really believe that the area of expertise really matters when it comes to that basic, foundational knowledge ?
That's like saying that a physics BS would be less qualified to teach multiplication to grade schoolers than a math BS.

[Anonymous No.11793385]

>>11793373
And his friends Everest Gaylaws, Growthedick and La Garage.

[Anonymous No.11793388]

>>11793307
Holy shit, that's the most beautiful girl I've ever seen, do you know who she is?

[Anonymous No.11793393]

>>11793388
she died of lung cancer in 2016

>>11793307
>This page intentionally not left blank, but then again, there's also intentionally nothing to see here.

>>11793322
you become

This thread wasn't very rich.

[Anonymous No.11793427]

>>11793388
>>11793307

Die fuckers

[Anonymous No.11793547]

What's the most palatable way to prove for a normie that [math]9\sum\limits_{n=1}^\infty\frac{1}{10^n}=1[/math]?

[Anonymous No.11793558]

>>11793547
Their difference for the sum up to n is 10^-n.
By DEFINITION of you have a sequence which stats arbitrarily close to a real number the limit of that sequence is the same real number.

0.999... is BY DEFINITION just another symbol for 1.

[Anonymous No.11793560]

>>11793547
0.9.... "is the closest thing to 1 that is inferior or equal to 1."
Suppose that 0.9... is not 1.

Then "0.0...1" exists and it's not null. But this means there's something smaller than it. Then there's something higher than 0.9... that isn't 1. Contradiction.

It's not rigorous but the idea is there.

[Anonymous No.11793571]

>>11793547
x = 0.99999999999...
10x = 9.99999999999...
substract to get 9x = 9

[Anonymous No.11793588]

>>11793547

>infinite series

[Anonymous No.11793591]

>>11793571
That's wrong, you can't work with infinite sums like they're finite, rookie mistake.

[Anonymous No.11793594]

>>11793591
This is for an intuitive picture. Rigorously 0.9.. = 1 by definition.

[Anonymous No.11793602]

>>11793588

[Anonymous No.11793609]

>>11793547
For normies just go with [math]3*\frac{1}{3}[/math]. The 0.999... arguments here are not populated by normies.

[Anonymous No.11793611]

H-hewwo OwO... I'm wooking fow a goooood book about C*-algebras! :3
Couwd any of you boys hewp me by weccomending one to me?? UwU
I'm already reading Pedersen btw but it kinda sucks

[Anonymous No.11793612]

>>11793591
you can if they converge absolutely

[Anonymous No.11793619]

>>11793609

the real answer is that this division is impossible in base 10 but humanity is too cowardly to say it

[Anonymous No.11793623]

Is maths up to and including PDEs sufficient enough to start looking into calculus of variations and Euler-Lagrange problems?

[Anonymous No.11793625]

>>11793611
You're writing like that because you want me to recommend Takesaki, aren't you?
>>11793623
Naturally.

[Anonymous No.11793630]

>>11788501
What's the convergence radius for the Euler product for zeta?

[Anonymous No.11793684]

Is there even a point to finite fields or is it just algebraic masturbation

[Anonymous No.11793688]

>>11793315
Well said

[Anonymous No.11793693]

>>11793684
They show up in a lot of places, yes>>11793684

[Anonymous No.11793694]

>>11793684
Both.

[Anonymous No.11793699]

>>11793684
finite fields are really basic stuff

[Anonymous No.11793720]

>>11793684
Well apart from Z2 being a model of Boolean logic, I mean they are just the arithmetic mod p^n. I know some Galois field stuff is relevant to RAID optimal hard drive backups and of course they pop up in cryptography.

[Anonymous No.11793730]

>>11793720
Please refrain from posting my wife here.

[Anonymous No.11793735]

>>11793720
A lot of theorems which work nicely for the orthogonal group fail or are much more complicated for F3, F2, it's frustrating

[Anonymous No.11793739]

>>11793730
Does she give good head?

>>11793730
It's even worse for F1

[Anonymous No.11793741]

>>11793730
Zettai urusanei! Stay away from my wife's son!

[Anonymous No.11793798]

>>11793684
If you are interested in the cohomology of a finite group, you can decompose that into primary components (one for each prime diving the order of the group). Taking coefficients in a field of characteristic p kills all components other than the p-primary one. In a similar way, you can localise/complete a space with respect to a prime and consider homotopy, homology or cohomology with coefficients in a field of a prime characteristic to either get p-local information about the space or trivial structures, depending on your characteristic. They have their use.

[Anonymous No.11793821]

What are some good math-related youtube channels? (Please no Numberphile, Tibees, Minutephysics and 3Blue1Brown).

[Anonymous No.11793846]

>>11793821
Ben Eater

[Anonymous No.11793850]

>>11793821
Nikolaj-K.

[Anonymous No.11793851]

>>11793821
Michael Penn

[Anonymous No.11793857]

>>11793821
Norman J. Wildberger

[Anonymous No.11793862]

Why do we hate 3Blue1Brown, again?

[Anonymous No.11793868]

>>11793821
Please do not make us a laughing stock of Reddit by posting Kurisu. It s because of you that the Fields medalists don't mention us in their speeches. An answer to your question is my home videos, also Harpreet Bedi https://www.youtube.com/channel/UCErLELnXehsJ7ycW4OJgfQQ, and https://www.youtube.com/user/MathDoctorBob for the little ones.

[Anonymous No.11793870]

>>11793868
Doctor Bob is based.

[Anonymous No.11793872]

>>11793862
I don't hate it, it's just that it's a middle term between popmath and serious math, they're not interested in doing anything highly complex, but they also strive to be better than popshit, meh, it's not for me.

[Anonymous No.11793880]

>>11793870
Indeed, and he actually looks pretty good now that he has glasses.

[Anonymous No.11793881]

Holy shit, so this is what a math girl is like

https://youtu.be/i_huFgSUBRg

Awesome

[Anonymous No.11793894]

>>11793881
That's a tranny, anon.

[Anonymous No.11793898]

>>11793894
Is that our anime tranny? (s)He is in the UK

[Anonymous No.11793902]

>>11793821
Journey to the Microcosmos is not math but is still good
Two minute papers is not math but it is still good
Mathologer is ok
Flammable Maths is mediocre content with a fun presentation
David Metzier is mediocre content with ok presentation
Dr Peyam is good to ok depending on the video
Mathologer is good to ok depending on the video
Michael Penn is good to mediocre depending on the video
Veritasium is good to mediocre depending on the video
Vsauce is mediocre
Mind your Decisions is good content with horrible presentation

[Anonymous No.11793910]

>>11793315
>>11793291
This

[Anonymous No.11793913]

What do you guys think of an anime/games/math site/youtube channel? Would you watch it? I might create one in that style.

[Anonymous No.11793918]

>>11793902
What a terrible selection. Some of these channels are good but there's nothing past the first semester of undergrad

[Anonymous No.11793920]

>>11793913
Mathematics is inherently anime.

[Anonymous No.11793926]

>>11793913
Pick one topic and stick with it unless you're prepared to do a lot of work on your videos

[Anonymous No.11793927]

>>11793894
That's definitely not a tranny. You're just unfamiliar with the british physiognomy.

[Anonymous No.11793930]

>>11793927
This is 100% tranny.

[Anonymous No.11793938]

>>11793913
I would watch kurisu step on me and call me a worthless failure while she lectures me about how algebraic geometry is useless and forces me to suck her toes.

[Anonymous No.11793951]

>>11793913
What would the actual content be like. This description makes me say "no", but a more detailed one could change my mind.

[Anonymous No.11793965]

>>11793913
I second the question. I'd watch it, even if I don't know what that would look like.

Also, is the AMS a political party now or what?

[Anonymous No.11793968]

>>11793965
>now

[Anonymous No.11793970]

>>11793913
You could do math in video games: computer graphics, ai algorithms, c how a tas works etc.
You could just do a series of math-heavy puzzle solutions for every puzzle game: Professor Layton, The Witness, Baldur's Gate etc

[Anonymous No.11793973]

>>11793920
A*e^x + B*e^(2x) + 1/2*e^-x + 9/13*sin(3x) + 7/13*cos(3x)

[Anonymous No.11793984]

>>11793970
>applied "maths"

[Anonymous No.11793987]

>>11793970
>The Witness
You misspelled The Talos Principle.

[Anonymous No.11793999]

>>11793984
This picture is backwards.

[Anonymous No.11794000]

I'm trying to compute the [math]\check{\text{C}}[/math]ech cohomology of [math]\mathbb P^1[/math] and of the affine line with the double origin over a field [math]K[/math] 'by hand', by using the cover [math]\mathfrak U[/math] by two affine lines, where [math]\text{Spec}(K[t])[/math] is glued to another copy of itself on the open subset [math]\text{Spec}(K[t,t^{-1}])[/math] via the morphisms [math]t\mapsto t^{-1}[/math], respectively [math]t\mapsto t[/math].

The projective line has [math]\check{\text{C}}[/math]ech complex
[eqn]0\to K[t]\times K[t]\xrightarrow{d^0} K[t,t^{-1}]\xrightarrow{d^1} 0[/eqn] with [math]d^0(p(t),q(t))=q(t^{-1})-p(t)[/math]. We have that [math]\ker d^0 = K[/math], since only the subset [math](k,k)[/math] maps to [math]0[/math] for [math]k\in K[/math]. Also, we have that [math]\text{im} \;d^0=K[t,t^{-1}][/math] clearly, ie [math]d^0[/math] is surjective. In particular, [math]H^0(\mathfrak U, \mathbb P^1)=K[/math] and [math]H^1(\mathfrak U, \mathbb P^1)=0[/math], and the rest are zero.

The affine line [math]\tilde{\mathbb A}^1[/math] has the same complex but instead [math]d^0(p(t),q(t))=q(t)-p(t)[/math]. This gives us that [math]\ker d^0 = K[t][/math] and [math]\text{im}\; d^0=K[t][/math]. Therefore [math]H^0(\mathfrak U, \tilde{\mathbb A}^1)=K[t][/math] and [math]H^1(\mathfrak U,\tilde{\mathbb A}^1)=K[t,t^{-1}]/K[t][/math].

My problem lies in interpreting the last quotient. I want to think that this quotient is [math]K[t^{-1}]_+[/math], ie, the ideal consisting of all degree [math]\geq 1[/math] polynomials in [math]t^{-1}[/math]. I think this because the set of constant polynomials is within the image of [math]d^0[/math], but I could be wrong.

Is the previous correct?

[Anonymous No.11794005]

>>11793987
Such a great game. Witness is good too though. I'd say Talos is just a bit better than the witness.

[Anonymous No.11794013]

>>11794000
>[/math]
>[math]

[Anonymous No.11794016]

>>11793926
Care to expand? I was thinking of doing something similar to https://rainheaven.neocities.org/ which is focused on tech/otaku culture.
>>11793951
>What would the actual content be like.
I'm still thinking about it, but maybe make in-depth reviews of japanese games mostly and animes (similar to Matthewmatosis and Joseph Anderson's reviews), the math part maybe at first solve advanced competition problems like the Putnam (although there are probably a lot of other channels doing that) or discuss about advanced areas that I'm into like homotopy, cohomology etc. I would appreciate if you guys have any ideas in mind.
>>11793970
That might be a nice idea for a video or two.

[Anonymous No.11794019]

>>11794013
? I'm pretty sure it all rendered correctly, at least from my screen

[Anonymous No.11794030]

>>11794005
Yeah, it really surprised me (namely because it cam from the devs of Serious Sam), but it ended up being in my top 5 vidya of the 10s.

[Anonymous No.11794034]

>>11793965
>Also, is the AMS a political party now or what?
Yes, American Mathematical Socialists

[Anonymous No.11794040]

>>11793821
I found CHALK recently. It's okay, but I haven't watched much.
Through the looking glass is more physics I guess but it's alright.

[Anonymous No.11794044]

>>11793902
>Flammable Maths is mediocre content with a fun presentation
He's such a fag but I like him sometimes
He's grating most of the time, /b/ tier humor but with math

[Anonymous No.11794057]

>>11794044
I honestly don't know how he has such a following. His humor is Pewdiepie tier, yet his content is graduate level math.

[Anonymous No.11794070]

>>11794013
lel

>>11794057
>yet his content is graduate level math
Show me 1 (one) graduate level video of Flammable Maths.

>His humor is Pewdiepie tier
What do you want to say with this? That we would have even more viewers if he lowered the bar on his math content?

[Anonymous No.11794074]

>>11794000
Seems correct to me, assuming your complexes are correct. The nasty part is to notice is that the degree 0 stuff is already in K[t], and so you get that _+ there.

>>11794016
>I would appreciate if you guys have any ideas in mind
Nope, sorry.

[Anonymous No.11794084]

>>11794044
>graduate level math
It's really the humour videos, integrals, undergrad problems and the few hard exams thing
>>11794070
Hello Flammy

[Anonymous No.11794086]

>>11794070
https://www.youtube.com/watch?v=jHN-nnFbCcI

[Anonymous No.11794088]

>>11794084
>TFW you realize Flammy browses /mg/

[Anonymous No.11794187]

>>11794086
I skimmed his thesis, which is on fractional variant of the zeta functions, so that seems close to him. That said, that's still rather straight forward symbol manipulation - I thought Graduate means post-Bachelor

[Anonymous No.11794192]

>>11794070
>That we would have even more viewers if he lowered the bar
nice freudian slip there faggot
stop shilling yourself on /sci/

[Anonymous No.11794197]

>>11794192
>stop shilling yourself on /sci/
No.

[Anonymous No.11794205]

[math]\displaystyle\prod_{n=1}^{\infty} \frac{4n^2}{4^2-1}=\frac{\pi}{2}[/math]

[Anonymous No.11794207]

>>11794205
epic fail

[Anonymous No.11794216]

>>11794207
LaTeX is gay.

[Anonymous No.11794218]

>>11794205
>>11794216
[/math]\displaystyle\prod_{n=1}^{\infty} \frac{4n^2}{4^2-1}=\frac{\pi}{2}[math]

fixed that for u

[Anonymous No.11794220]

Yukiko or Rise? Which is the most mathematically logical choice?

[Anonymous No.11794227]

>>11794220
Chiaki

[Anonymous No.11794233]

>>11794220
probably provably undecidable

[Anonymous No.11794286]

>>11794220
Rise is used goods.
Like a ravaged watermelon down there

[Anonymous No.11794298]

>>11794286
>Like a ravaged watermelon down there
You say that like it's a bad thing.

[Anonymous No.11794301]

Which schools should be my top choices for post-doc? I'm in algebra. I am also a weeb so Kyoto seems kind of tempting but I know very little Japanese (yet).

[Anonymous No.11794313]

>>11794301
Could you possibly give us less detail please?

[Anonymous No.11794314]

>>11794301

[Anonymous No.11794316]

>>11794286
>Rise is used goods.
She's most likely a virgin in the game.

[Anonymous No.11794321]

Outside of finance/economics, what are some frequent applications of stochasic calculus?

[Anonymous No.11794322]

>>11794316
>Idol
>Virgin
LMAO dis guy

[Anonymous No.11794323]

>>11794301
>Kyoto seems kind of tempting but I know very little Japanese (yet).
How do you plan on being accepted on Kyoto U then? You think they'll simply just let you in one of the top Universities of the country because you're american? Guess what, no one in the world cares about that fact.

[Anonymous No.11794327]

>>11794322
You realize idols can't date anyone otherwise they'll lose a huge part of their fans, right? You seem clueless about some aspects of japanese culture.

[Anonymous No.11794330]

>>11794323
>You think they'll simply just let you in one of the top Universities of the country because you're american?

[Anonymous No.11794332]

>>11794327
You realize idols have all their holes ravaged by producers from their early teens, right? You seem clueless about some aspects of japanese culture.

[Anonymous No.11794339]

>>11793881
anons if you are so smart why is this tranny studying at cambrige and you are not

[Anonymous No.11794344]

>>11794314
holy fucking based

[Anonymous No.11794345]

>>11794323
I'll give Mochizuki a firm handshake.

[Anonymous No.11794347]

>>11794332
>You realize idols have all their holes ravaged by producers from their early teens, right?
You seem to naively believe japanese culture is the same as american shitty culture, thinks like that aren't normalized nor accepted in the japanese pop industry like it is in the US, stop projecting the failures of your country into Japan.

[Anonymous No.11794355]

>>11794313
If I post my real name, will you go through my research papers and give some recommendations?

[Anonymous No.11794356]

>>11794347
>This absolute level of denial
All just to protect his tattered onahole of a waifu, Rise.

[Anonymous No.11794362]

>>11793611
Kadison-Ringrose

[Anonymous No.11794367]

>>11794323
>walk up to Mochizuki
>"you completely annihilated Scholze, yamato damashi once again BTFOs the western pig dog"
>get a postdoc position

[Anonymous No.11794370]

https://www.youtube.com/watch?v=J8LxORztUWY
JUST IMAGINE caring about that completely fabricated shithole that is jpop and kpop for a single second of your life and having some kind of pride because of it

[Anonymous No.11794371]

thank god this shitpost thread is soon over

[Anonymous No.11794382]

>>11794301
I can''t say for sure, but I would assume specialisation, supervisor and networking are more important than the school (excluding some obvious elite places). I could be very very very wrong, though.

[Anonymous No.11794396]

>>11794370
>t. has never listened to J-pop

[Anonymous No.11794418]

>>11794371
agreed im actually disgusted by that stupid fucking weeb thinking jpop industry is some kind of perfect thing and is much better than shitty western pop industry

[Anonymous No.11794443]

>>11794418
City pop is pure kino, brainlet.
https://www.youtube.com/watch?v=7ijMDQgvW0o

[Anonymous No.11794456]

>>11794443

is this what music sounds like in the 2020s?

[Anonymous No.11794461]

>>11794456
Music died with Brahms, everything after that is just noise.

[Anonymous No.11794478]

>>11794443
>post about current situation in jpop
>responds to it with a music clip from 40 years and how is it "kino" and acts like it is a valid answer
sorry to break it to you bud but you are the one thats a brainlet and extremely big one too

[Anonymous No.11794486]

>>11794478
>He thinks his opinion holds any value at all to me
Oh, how very sad of a person you must be

[Anonymous No.11794495]

>>11794486
>how very sad of a person you must be

[Anonymous No.11794497]

>NO GUYS IM NOT RETARDED I WAS JUST PRETENDING AND AKSHTUALLY IM A CHAD AND YOU ARE A STINKY VIRGIN
yep you showed me dude

[Anonymous No.11794504]

if sex is commutative, doesn't it mean that getting pegged is still straight sex?

[Anonymous No.11794510]

>>11794504
Is sex associative?

[Anonymous No.11794511]

>>11794504
No, commutativity simply says that MW = WM; woman-on-top is still straight sex.
You're asking for [math]MW = W^{-1}M[/math] , which is false.

[Anonymous No.11794550]

>>11794510

Only if the expression has a single gender. Because a girl fucking a straight couple is based but a man fucking a straigh couple is cuckholdry

[Anonymous No.11794595]

>>11794550
Unironically nothing wrong with cuckoldry.

[Anonymous No.11794758]

>>11794595
Will this be the first mg thread to reach 400 posts?

[Anonymous No.11794789]

>>11794758
No but Rise's cunny was the first to reach 400 dicks by the age 15

[Anonymous No.11794982]

>>11794789
Why are you being rude to that mans wife?

[Anonymous No.11795009]

>Mobiüs strip
>Klein bottle
>Gabriel's horn

[Anonymous No.11795024]

>>11795009
>>Mobiüs strip
>o
>ü
Do that again and I will bathe in your blood.

[Anonymous No.11795034]

>>11795024
Bathe in THIS
*unzips*

[Anonymous No.11795035]

>>11794088
His humour is so unlike /mg/ though
He's just a /b/tard that turned out somewhat successful

[Anonymous No.11795048]

>>11795034
I'm sorry, anon. My eyesight has gone worse with age. Was there something I was supposed to see?

[Anonymous No.11795060]

>>11795048
Kek
Based

[Anonymous No.11795250]

>>11795048
You wouldn’t say that to my face irl animeposting twink.

[Anonymous No.11795262]

>>11795250
You sure?

[Anonymous No.11795272]

>>11795262
Yeschad.jpg

[Anonymous No.11795283]

>>11795272
I've seen a few phalli in my life. Why do you think yours would be special?

[Anonymous No.11795292]

>>11795283
[math]f(x)=x^x[/math]

[Anonymous No.11795310]

>>11795292
Suppose I gave you my email, would you send me proof of such a claim?

[Anonymous No.11795319]

>>11795310
No that would be gay haha

[Anonymous No.11795322]

>>11795319
So you were lying about the growth.

[Anonymous No.11795331]

>>11795322
You are so desperate for dick you are trying to bait a stranger into sending you a pic of his?

[Anonymous No.11795337]

>>11795331
Partly that, partly for pure entertainment.

[Anonymous No.11795346]

>>11795337
Ok post your email then and back those big words up.

[Anonymous No.11795361]

>>11795346
[e-mail] it's a 10minutemail

[Anonymous No.11795388]

>>11795361
Sent.

[Anonymous No.11795407]

>>11795388
And received, sadly it is quite small and I can't see it. Also, they aren't doing the day light saving thing with their time, I see.

[Anonymous No.11795408]

>>11795361
No response huh? Talks a big game and nothing to back it up. Sad!

[Anonymous No.11795417]

>>11794758
400 reached!

[Anonymous No.11795419]

>>11795417
[math]400![/math] is a really big number.

[Anonymous No.11795424]

>>11795419
Unlike the genital of a certain poster.

[Anonymous No.11795524]

30 posts of consecutive samefagging is really fucking sad, I hope you move on

[Teacup !obkpuSWh5M No.11795526]

>>11795524
(You)

[Anonymous No.11795535]

>>11795035
/mg/ humour is literal twelve year old Yukari humour and shitty one liners, tho, it's not really much different from /b/.

[Anonymous No.11795560]

>>11795535
So, Flammy is basically /ourguy/?

[Anonymous No.11795575]

>>11795535
The general mood around these parts is very different from what he portrays in his videos though.

Also page 9

[Anonymous No.11795595]

Can we get a new thread?

[Anonymous No.11795662]

>>11795595
It’s already up

[Anonymous No.11795664]

>>11795424
Beggars can’t be choosers you ungrateful twink.

[Anonymous No.11795670]

>>11793821
epic math time

[Anonymous No.11795715]

>>11794314
That's obviously a scam, but...

[Anonymous No.11795865]

new thread

>>11794633