#serious-discussion
1 messages · Page 151 of 1
idk, but I remember some keys are at different places
I usually type without looking, so it was really annoying
It's the German layout, for example there is z instead of y next to t
QWERTZ layout?
Yes
maybe that's why 
you’re in France, is that right?
don’t they use AZERTY over there?

I think having the A where the Q is would throw me for a loop lmao
just don't look at the keyboard when you type
I don’t look
That’s the issue
lmao
I would just start typing nonsense bc of diff layout

I think Megumi means still having QWERT
it literally takes 1 second to switch between two layouts
Just the labels being different
I want to be able to write \forall and \geq and \exists with my keyboard now 
it was an issue when we participated in a programming competition 2 months ago. One teammate only knows how to type in QWERTY, and another only knows how to type in AZERTY
and of course, we only had one computer

we ranked quite high at the end, by some miracles 
infinity is Compose+8+8 for me, \ge is Compose+>+= for me
I also have a latex layout keyboard, but those two I don't type using it because using the regular keyboard is more convenient
forall I type with \forall in my latex keyboard, exists with \exists
I don't have alt-codes, that's a windows thing
In my computer it's control-shift-u and then you can type in a code, but I never use it because memorizing unicode code points is dumb
What's a latex keyboard?
you know how you can switch between different language keyboards?
like english, spanish, german, arabic, etc
you can just install a latex one too
or at least I can, idk what OS you're using
I can on Android
this is what I use iirc
I think this is the one I use, I downloaded both the IPA and LaTeX keyboards from here https://github.com/moebiuscurve/ibus-table-others
indeed
thanks for this
woah that's cool
The way I write Σ or ∫ is not with my English keyboard
I literally just write せき and ∫ pops up immediately 
Same thing with Σ

\sum is a keyboard shortcut on my phone
привет
You're japanese?
No but I speak it
Did I stutter?
no maybe coz ur just written down things from ur comp or smt
D-did i s-stutter?
rocket catz
What’s you guys’ favorite number?
42
man brilliant already seems to suck
anybody know something similar but better?
tryna find stuff for my half siblings who are about to be knee deep in college
some next gen stuff, not a textbook
I’d say that reading textbooks is a mandatory skill in college
yeah it's a really ineffective skill I guess
compared to say going to see a tutor or office hours tas
definitely wouldn't call it mandatory. At least in the case of basic maths
e.g. calc, diffeq, la
The ability to read textbooks includes the ability to summarize paragraphs and develop a new perspective regarding the topic the book is talking about.
bro I'm talking about math
I should’ve said the ability to read and understand math textbooks
what are you talking about, history of architecture?
I am pretty sure they can read and summarize topics from new perspectives, they're high school graduates
You won’t survive in college, the saharan desert, or Texas without textbook comprehension skill
Math textbooks are much harder to read and understand effectively
New gen resources are often subpar compared to them imo
absolutely true, which is why I don't recommend learning via them
yeah that's kinda ridiculous to me. I've had textbooks which had like, one simple trick that a TA was like nah dude it's like this
that I would've bashed my head against for 3 hours otherwise
so, any recs on topic or just a little opining to go around about?
khan academy or youtube
pauls online notes
you can essentially just google around for the topics youve described since theres like infinite resources on them
you gotta be kidding me dog those are what I used like six years ago when I was an undergrad
I don't think that really answers my question though does it
ok...?
I am looking for some next gen stuff
like brilliant
like a duolingo for maths
I'm tryna be cool cause you didn't read my question but I also know you kinda suck so
let me just say, maybe read up first sometimes
khan academy is pretty much that
good rec though. I'm getting caught on tiny things in the presentation but it's definitely better than paul's online math notes.
miniscule things, like saying a function is defined for all real numbers except x= <a number> but never clearly stating that the function is of x
I am happy to report that I have done the last required Imagine Math course
All 36 of them
bad
69420
is Tame Impala the greatest artist of our time?
One of my favourite bands
isnt tame impala just 1 person
Hes very close at this point...
Even rihanna wants to be him
You can be a 1 person band
Guys, did I waste my time learning stuff that I'm not gonna use in the future? Seriously whats the point of learning things that aren't gonna be used.
what kind of stuff?
Everything, math ofc, but also history, geography, science, etc.
like bro what is knowing the timeline of ww2 gonna do for me
”what’s the point of not being ignorant”?
no point because i feel like i could've spent the time on doing things like exercising or learning stuff that actually matters
just because you didn't find that knowledge useful to you, doesn't mean there are no people for which it is useful
Ok
IMO learning lots of different kinds of things trains you to think and problem solve more efficiently. like you learn lots of different ways of considering problems and organizing information, and since you use those methods on lots of different kinds of information (whether historical, linguistic, logical, etc), you get really used to these abstract mental manipulations
and then you use them all the time subconsciously when making decisions or analyzing situations in pretty much any job
i dont really like the "someone else might use it" argument because i think it undersells the value of these 'soft academic skills' and seems to pretend that the value of academics is exclusively in the pure content
everyone uses it, and if you don't... you could be! someone else is and they'll leave you in the dust for it
vulfmon
If you learn more things, you’ll comprehend and appreciate the world in a much deeper scale
Wow... I never knew there was subconscious benefits to learning. That makes me feel a lot better about spending so much time watching educational YT vids cause I really thought that I wasted my life learning that stuff which doesn't matter.
Also if that's the case, does that mean any knowledge is useful? What about knowledge about stuff in video games like Minecraft speedrun tips? Did I waste my time playing video games or not?
Although I really hope this isn't some propaganda that teachers use to make students more happy with learning or something... lol
Srry just have a lot of thoughts cause this is weird :/
eh i think it depends, as long as its balanced i think any kind of learning is healthy. i definitely improved a lot of my problem solving / visualization / coordiation skills from the types of games ive played
but i would say if you left people to their own devices they'll usually just focus on improving on the kinds of learning that they're already good at, since you'll have successes faster and that feels more rewarding
so school is good for forcing people to balance that out
instant gratification going wild
ok, ty for the info
fr i was depressed cuz i thought i wasted my life, ty for helping
Ryoji Ikeda is not even the greatest of our time and yet he did this
guys
i was watching an interview with the director/writer of "bird box" i think
and he said the monster in the movie was inspired by things like infinity? cuz its so unknown?
he also said smth along the lines of "infinity could be sitting on the swing outside "
what the fuck does that even mean bro
this is what happens when people watch numberphile
let the non maths ramble
real
okay i may have been too harsh
what he actually said is hes inspired by it cuz its unknown
and smth unknown personified is scary
i just thought its a bit funny
lol ryc there is no greatest artist of our time, trying to define one is entirely subjective so i don't really see the point
for example, i always see people in the comment section of songs calling it one of the best songs ever, and i'm just thinking, really? they can't ALL be one of the best songs ever
quantum ur forgetting abt me
my singing is so top tier

Ok ur mad
huh
yeah its only one and its The Less I Know The Better
so true
its not lagtrain or "i am so kawaii cute" or scalp ripper or whatever
what necessarily makes that song better than all of the other "one of the best songs ever"
like, i can see when a song is good and stuff, but calling it that is always too far
even for songs that i actually feel things about
it has to have a good amount of depth to the lyrics without being so deep as to be unrelatable. it has to have a crunchy, satisfying, earworm start riff that gets in your head but that quickly transitions away into something more layered and substantial, it needs to flow in and out of the bridge delicately so as to trick the listener into forgetting the song is nearly over
i thought of other things it needs to have but tame impala is bad at those things so i didnt say them
what about music without lyrics or guitar then?
i assume riff implies guitar
Riff could be any melody
A hook
Music without lyrics could be the best
idk
i used to think it was
idk I like songs that start a bit slow, so that it takes 20 seconds to a minute getting to actual song
if it starts with something that should get into your head instantly it feels cheap
How Long performed live at Victoria Hall in Leeds 2020 as part of Paul's "Soulfully Distanced" concert. The full concert is available as an HD download here: https://paulcarrack.net/digital-store/full-concerts-live-videos/live-at-victoria-hall-leeds-2020
Filmed in September 2020 at the magnificent Victoria Hall in Leeds using twelve cameras, th...
lol (i dont think anyone can answer that question because it is entirely subjective)
ryc has the correct view on things that matter but once they don’t matter his opinions go down the drain
Can i ask yall if you have a math degree what job did you get. Im currently an applied math major and trying to see what i can expect or shoot for
Your uni most likely has a career service which you could visit
They do, but i wanta see the possibilties
Majority of my math peeps that graduated have a job title similiar to "Data Analyst", 70-120k/year
I have a new question.. what do yall do when something says " closely related field"
what
Like this is for data analyst in my area. "Bachelor's degree in Computer Sciences, Information Technology/Systems, Business Administration or a directly related field,"
Hi, im an undergrad physics&stats student and am looking to take a math class. Should i take discrete math or number theory? I dont have much knowledge in either classes, but am slightly leaning towards number theory since ive seen some interesting conjectures etc. would anyone like to share their thoughts please
isnt everyone a data analyst
why would you need to kill yourself with a math degree
meowwwwww
why is the server owner a furry
wouldnt it be lovely if Algebra didnt exist
rather itd be lovely to have a Algebra deactivation button
ill just press it in math class just to see what my math prof gonna teach
yeah actually i dont like the moving numbers around part of math, its not neat or cool or rewarding at all
its alright if its just a part of it
it fucking sucks
understandable
everything outside of Algebra is really COOL
algebra too is allowed to be cool sometimes
but it can quickly get really redundant
ur probably thinking of the formula part
all of Algebra
zamn indeed
Algebra gets obvious sometimes, also its not something that really needs attention to the point where all you do in a class is Algebra
use the time to build familiarity with the new objects
people will build the algebra as a result of it
imagine being subjected to 3 hours straight of the professor trying to explain how they got from one part to the other
everyday of the week outside of weekends
why is a remainder theorem Chinese
No more hesitation
the question first appeared in a Chinese text
since you are a Phys stat guy I recommend probability theory
the first place the statement/a similar was written down was in a chinese text ~500 AD iirc. the first proof/algo was given in the 6th century by an indian mathematician. it later showed up in fibonacci's famous work, and the first generalization and complete solution was given a few years after liber abaci in a chinese work that i forget the exact name of but had something to do w the number 9.
source: i wrote an essay on the history and mathematics of the crt and showcased 2 proofs two or three years ago for a math class
was a rhetorical question lol
funny I+J = 1 implies R/IJ = R/I × R/J
We just did CRT (cough cough sun tzu’s theorem) last week in number theory
No I mean like
the job title
are you an assistant prof? associate prof? something like that
adiunkt dydaktyczny 🇵🇱
No idea what it translates to in some kind of international framework.
Probably some kind of senior lecturer
In my language I definitely couldn't be called "professor" because it's the highest-ranking and most prestigious title in Poland.
arent there different levels of "prof"
Just two in Poland, but they're both above what I am
Now prove it for rings 
anyone knows anything about SIR-modelling and how to visualize it in a graph?
thats that pandemic stuff right
isnt there a set of pretty simple equations for it
Just plug and chug surely
it’s actually the same proof don’t bother lol
bash proof is crazy
hrlp pl,s
sounds like adjunct professor in english. professor is a catchall term here with the adjective that comes before giving the rank
It might be reasonable to define 1/(1/0) = 0 right?
yup, as a fraction I write it
you are going to "proof" that 1=0 right?
2=1 but yeah
I think I actually solved that with division by a-b!, but its a bit unstable, as division by zero is to expect
go! Bye! and Sell!
no
You have to make a bunch of contrivances SPECIFICALLY for 1/0
That in turn make your structure boring
alright explain
So 1/0 is its own number?
It’s like a nonstandard number system where we appoint a value ‘a’ to 1/0 then
why we always ignore the base of log while calculating the log
do we
You cannot ignore
people who write log instead of ln need to be killed (in minecraft)
log is base 10 though
Also ln is french and cool and awesome
<@&268886789983436800> they're harassing me
Also wdym i didn't say anything
....
You're tripping
you know tampering with evidence is a crime in the us?
in fact, i didnt say anything either
what were we talking about?
honestly
Wait until you hear about audit logs
Wait i shouldnt have said that
ill incriminate myself
goddammit
Wrong!
dont look at the audit logs
You’re probably fine, just don’t feed the trolls
You said earlier that people are animal so hunt something
That’s almost admitting to zoophilia
Remove the almost
that means that by taking 10 we are taking each one in general so
if the log of something with the base power of 10 can also be calculated with log of something which is relate to 10
more like of a sdiscrete maths logic
but waht if the base value is 3
hi
What did he say
I view humans are animals in term of sexual preference or something like that
Helo
Wadap
what you mean ?
Wassup
Nothing much either
Same kind of, joined it a while ago but nevr talked
Mostly cuz most discussions idrk alot abt so its more comfortable to read other peoples'
Helo
Are there any servers like this for social sciences?
I saw that this is part of a science network, but I'm not sure if there's social science servers
I am posting this assuming that the Venn diagram of gamers and people who are into math would be high here and I am looking for likeminded people in that regard.
I am in the very early stages of making a math game for high-school and possibly early university math. The ambition for the game is to feel like a real game. Therefore, I keep the math optional, so that players self-motivate to use math (vs. virtually all math games, I am aware of, where not doing the math stops the gameplay). In line with George Polya's view on guessing being fundamental to math problem solving, you can always get around the math through guessing. To keep it short, take a look here: https://baugarten.game/
Good games are built on feedback. So let me know what you think and tell me about other places with likeminded people I can go to for feedback.
anybody here from cambridge??
Hello!
Are there people that want to study undergraduate maths with me 1h a week at least for fun ?
(doing some exercices, learning the history of the concepts) etc
Hey is anyone here from Sweden or has been to Sweden? I’m in my final year of an undergraduate math degree in New Zealand and am thinking about Gothenburg University for a Masters in Logic. Would love to hear from you if you have any thoughts or if I could ask you questions 🙂 🩷🌸✨
why 1/x turns into or equals to x^-1
if you ever learned how negative exponent works then you can get it
Exponent rules, x^m * x^n = x^(m+n), someone said what if negative numbers, so if we do x^n * x^(-1) we get x^(n-1) which is the same thing as if we divided by x.
zoop
The science network didnt start off with social sciences. If you join one of the servers there should be a link in the networking channel of one of them
This is old information though, so dont take my word and try and find it through joining the other servers
Because that's how it's defined
x^-1 existing means x* x^-1 =1
What times x equals 1? Well 1/x of course
Did or didn’t start off with social sciences? Because you said didn’t and now I’m confused
Didnt start with social sciences. Each of the servers had a network channel which added other servers gradually
One of those servers added was a social science
Ohh
I don’t see it in this server’s network channel- which server has it?
I love math and social science and this server was easier to find
I cant tell you because this is old info
Its likely inactive eitherway
What about social science?
Like economics?
Idk if that counts
wow
this dude would be genious at discrete maths
hey
btw i got a very interesting qus
how the hell someone came with the product rule of differentiation
notice a pattern in computing the derivative of products of functions from the definition
Thanks for the compliment and I think there are other brilliant members on the server that could help you with discrete math than me
The product rule comes straight from limit definition of derivative
But there are other ways to interpret it
Wikipedia has this famous picture
In calculus, the product rule (or Leibniz rule or Leibniz product rule) is a formula used to find the derivatives of products of two or more functions. For two functions, it may be stated in Lagrange's notation as or in Leibniz's notation as
The rule may be extended or generalized to products of three or more functions, to a rule for higher-or...
I just want a server like this one but for social science
Yeah I meant what specific social science
There are plenty of servers that talk about philosophy or sociology or economics as examples
Idk if these all count as social sciences
But idk if you are likely to find a channel that talks about all of these
Ah sociology or anthropology are my focuses
y=-9(|x^2-0.5|)+2 Does anyone know how to describe this transformation?
hi
where can I download this book :Cambridge IGCSE™ and O Level Additional Mathematics Worked Solutions Manual with Digital Version (2 Years' Access)
3rd Edition
tried to buy it online but it says no shipping method
what tricks you usually do to understand and solve discrete maths
@orchid badger
こんにちは
understanding the material?
Writing coherent proofs
hey
its just my name is in kanji
but am not japanise
where are you from?
ここって英語だけだと思います
“Your name” is Hayao Miyazaki but you’re not Japanese…? I don’t buy it.
なんか突然日本語で草
Thinking about buying a used Macbook for studies. I have two options:
- A MacBook Pro 2020 w/an Intel processor and 16gb of ram
- A MacBook Air 2020 w/an M1 processor and 8gb of ram
Which should I get? I really want an Apple Silicon processor, but also want 16gb of rams.
M1. Sooo much better than intel.
I know, but the 16gb of ram is recommended by the university i'll be applying to next year or year after
I will more than likely apply for the Mathematics undergrad program, do you think the 8gb would suffice? I've heard 16gb are essentially the standard minimum nowadays
🤷♂️
mane
m1.
m1 for sure
I think 8 gigs would serve you fine
especially if you're doing math
Okay, thanks :)
Hopefully
Is this the better of the 2 discussion rooms?
I think 1gb of ram is fine
pcsx2 runs fine
but the other one is a macbook pro
even the intel pro better than m1
its apple, what do you expect
🐑
This might be a stretch but can someone write me a letter of rec 😭
It's for an internship and my school is on spring break 😭😭😭
Nobody here knows you enough to reasonably write you one
(Or maybe someone does but not the generic person)
It'd be fraudulent
why not email a teacher?
Maybe you can get a friend or relative to write you one?
i got you
U HAVE A MACBOOK
CAN U HIRE ME AS UR PERSONAL INTERN
???
For real?
no he's trolling
how come tanhx function is one to one function if it gets to one after a time
like
after a specific x we al get the same value of tanhx
it doesn't get to 1
On caseoh
wut
I mean
What kind of fun ring it is where there is one y value for more than one x domain
alright @fringe summit @fervent pebble i can explain how continuous time markov chains are related to pdes now
$$\frac{\partial}{\partial t} \mathrm{E}i[s^{X(t)}]=\sum_j \mathrm{Pr}i(X(t)=j)\sum{k}g{jk}s^k$$
in finite dim this is the same as
$$\frac{\partial}{\partial t}\mathbf{P}_t=\mathbf{P}_tG$$
suremark MSC2020 60G40
where $(\mathbf{P}_t)_ij=\mathrm{Pr}(X(t)=j,|,X(0)=i)$
suremark MSC2020 60G40
wtf
and $\mathrm{E}_i$ is just conditional expectation on $X(0)=i$
then you get an equation like this
suremark MSC2020 60G40
anyway
uhhhh hopefully that didn't mess my whole explanation up 
@storm sage u might find this interesting unless u already know it
it is hard to read when split across lots of messages
we showed in class that probability densities for brownian motion follow the heat equation 🥰
i have this saved to look at later when im in a probability mood
tyyy
wait heres the condensed version
suremark MSC2020 60G40
lmfao i love the closing line
thanks!
@storm sage hopefully this is better
yesterday i mixed up the forward equation with the backward equation and i got confused for 2 hours
yayy
suremark MSC2020 60G40
very clear
cool, thx for making me improve it
so continuous time markov chain = discrete number of states, but time is continuous?
yeah exactly
ahh
it's basically a regular markov chain, but each state is separated by intervals of exponential distribution
very cool
suremark MSC2020 60G40
at least that's how my book notates it
neat
the only edge case is continuous time chains can explode
suremark MSC2020 60G40
which they call explosion
damn u oppenheimer
what happens to the markov chain after that then
it just goes through like infinitely many states in a finite time?
i guess so yeah.... i need to do more problems with them
suremark MSC2020 60G40
to make it non-exploding 
@neat lintel you still here, sorry I got distracted
ok let me spread anaNT propaganda again
stock exchange moment
Who here deadlifts 200kg?
your mom when she stands up
I used to do weights, but I never did for 1 rep max, so I have no idea if I could have done 200kg. My highest deadlift weight attempted and finished is 7 sets of 7 reps of 85kg with 30s rest between sets, close stance.
If I were doing wide stance, 1 rep max, I might have been in striking distance, back then, but I've been mostly training running recently, so definitely not now.
guys can someone help me post something on reddit. i have a new account so it will get removed but its important
i have a questionwhen we say that a set is antisymetrric
is antisymettric same as reflexive
me
205kg
conventional
have a video of it
S:200kg B:132kg D:205kg
88kg
My head hurts
Sorry I slept, it's alright
Amazing, how long have you been working out? How many calories per day?
This must be a joke
This isn’t like for credit or anything but the combination of TeX gore, the ordering of the answers and the subjectivity of the question is certainly something
85 kg isn't my 7rm
It's my 7x7 rm
If you really you can do nearly 50 reps in a little under 7 minutes at 75% of your 1 rep max, then hats off to you. I have no idea how you do it.
Hey guys. I just made a YouTube video, and I would really like some feedback on it. Here's the link: https://www.youtube.com/watch?v=Q2p4prE7PAQ
@vast wraith @dapper badge
Nice, I wanted to learn some of that stuff in relation to geometry of moduli space of curves
Me too
the approach described in the paper i linked in #math-discussion seems to be the simplest to constructing the figure for the automorphism group of the klein quartic… but i’m still stumbling over me simply not having been exposed to rather introductory stuffs before
Have you seen that Harrer Zagier paper of the euler characteristic of the moduli space of curves? @dapper badge
Yeah, that's something I want to read at some point
Me too
We should read it together
I haven't actually looked at it so idk what kind of math it uses
There are many descriptions of Klein quartic
i have noticed haha
I havnt read that paper, but the classical constructions are pretty understandable to me.
Combinatorics
Coloring polygon
problem is i’m not really familiar with the theory of riemann surfaces
I'm down
Check out the book by Girondo Gonzalez-Diez.
They talk about Klein quartic in detail there
really all i have to go on is the figure in klein’s original paper, and the description in terms of the locus in CP2
oooh
amazing, i certainly will
Is this something you'd want to do this semester or maybe next semester? I'm also free for most of May I think, but June and July are probably busy for me
We could do it in may
Ok that sounds good to me
Can you explain to me how teichmuller space mod mapping class group gives moduli space of curves
So do you understand how the mapping class group acts on teichmuller space
I don't know what teichmuller space is
Oh ok. So lets say you fix some Riemann surface of genus g, call it S
I'm using S essentially as a reference point for complex structures on surfaces of genus g. So any other genus g surface X can be given a complex structure via a diffeomorphism f: S -> X. Now I'll call two complex structures (X_1, f_1) and (X_2, f_2) homotopic if there's a map g: X_1 -> X_2 such that g o f_1 is homotopic to f_2
The set of complex structures modulo this homotopy equivalence relation is the Teichmuller space of S. The key point is that for g >= 2, it's homeomorphic to a ball of dimension 6g - 6 (and in particular, contractible).
Now the mapping class group of S acts on Teichmuller space as follows. Say I have an element of the mapping class group [g] and a complex structure [(X, f)]. Then I get a new complex structure via [(X, f o g^-1)], where I've applied a representative g^-1 of [g]^-1 to the surface S
Then the orbit of [(X, f)] is all of the points [(X, h)] where h ranges over all homotopy classes of diffeomorphisms S -> X
You can sort of define the moduli space of curves to be the quotient by this action, but the point is that in the quotient space, you've now forgotten the homotopy class of the map. So points are just isomorphism classes of curves of genus g
I think that's how it goes, I'm still learning this stuff too
I'm confused because isn't that the entire teichmuller space, the way you defined it?
Not quite. Let's use the specific example of the torus (even though it's genus 1, things still work out). So we'll fix S to be C / <1, i>. A homotopy class of complex structure on the torus is uniquely determined by a lattice in C modulo scaling and rotation. Idk if that's obvious, but I think it's illustrated better by example. So like if I have an ordered basis for a lattice in C (which is how every torus is constructed), then it's isomorphic to the lattice generated by <1, tau> where tau in the upper half plane after I rotated and scaled my lattice appropriately. The corresponding complex structures on the resulting tori are homotopic via that scaling and rotation. So Teich(T^2) is the upper half plane.
Now the mapping class group of the torus is SL(2, Z) because any homotopy class of diffeomorphism is uniquely determined by action on generators of pi_1 (that's not immediately obvious but it's true). Then the action of mapping class group on Teich(S^2) is given by fractional linear transformation. You can see this by fixing a point [(X, f)] corresponding to the lattice <1, tau>. Then the matrix (1 1 \ 0 1) takes <1, i> to < 1, 1 + i>. Since f takes <1, i> to <1, tau>, it takes <1, 1 + i> to <1, 1 + tau>. Similarly for (1 0 \ 1 1) except now you have to pass through the equivalence of any one lattice <lambda_1, lambda_2> with the lattice <1, tau> so it's a little more annoying.
Anyway, the resulting quotient is the standard fundamental domain you know for SL(2, Z).
I guess maybe the other way to think about Teichmuller space is in terms of surfaces with markings, i.e. surfaces S with a homotopy class of generators for pi_1. It's also not obvious that these give the same construction, but now when you mod out by the action of mapping class group, the orbits are just biholomorphism classes of Riemann surfaces of genus g
Yeah ok maybe this is the better way to think of it. So a marked Riemann surface of genus g is a Riemann surface of genus g, say X, along with a choice of generators C for pi_1(X). Then (X, C) is equivalent to (X', C') if there's a biholomorphism f: X -> X' such that the curves f(C) are homotopic to the curves C'. These equivalence classes give you the points of Teichmuller space of genus g surface. Then when you quotient out by mapping class group, you forget about the markings so you only care about X up to biholomorphism.
Oh, I guess I didn't mention how the biholomorphisms play into the original description, oops
Hmm maybe I'm confused because in Bers' paper it's all just homeomorphsims up to being homotopic to identity. I guess it's true that a conformal homeomorphism homotopic to the identity is necessarily the identity map so maybe these are equivalent constructions
thats funny as fuck
ping me in #discussion
no
oops extra dollar sign lmao
Lmfao
hi, can all classical geometry/ synthetic geometry be stated in a way that uses algebra , real number, or something similar to set theory?
(such as similarity of triangles and bisector theorem)
I mean , all these problems in geometry that should be proved with Euclid style be proved with modern mathematics?
So can euclid’s axioms be stated in terms of set theory?
yes
the statement may not be particularly elegant though
the axioms of ZF (or indeed a much weaker system than ZF) are sufficent to encode turing machines, and therefore any finite computation, including determining whether an argument from Euclid's axioms is valid
to more directly address the question
there exist axiomatizations of Euclidean geometry in the style of modern mathematics, yes
the most famous is Tarski's axiomatization https://en.wikipedia.org/wiki/Tarski's_axioms
Tarski's axioms are an axiom system for Euclidean geometry, specifically for that portion of Euclidean geometry that is formulable in first-order logic with identity (i.e. is formulable as an elementary theory). As such, it does not require an underlying set theory. The only primitive objects of the system are "points" and the only primitive pre...
(which is what proved that Euclidean geometry is decidable, a fact that I used implicitly in my above argument about Turing machines)
Tarski's axioms explicitly avoid set theory though
i am not aware of an elegant construction based on set theory
you can do "bad" constructions based on set theory by doing what i did above, or any other standard way to build up mathematics from set axioms
but as for "nice" constructions, i would not be able to tell you
Does the construction of R, R^2 and so on count?
those are euclidean spaces but not euclidean geometry in the classical sense
If you're willing to accept that, then the usual way lines and planes are dealt with doesn't seem so far off.
as they have a notion of a metric and stuff
and generally dont care about constructibility
like you can very easily square the circle in ℝ²
which you famously cannot do in euclidean geometry
The euclidean axioms vs constructability via ruler and compass are different things though?
the euclidean axioms are about constructibility.
Idk, I get that they are meant to mimic constructibility.
But something like "between any two points there is a line" seems easy to deal with set theoretically.
you can use ℝ² as a basis on which to construct euclidean geometry
but the construction of ℝ² itself does not suffice
its too strong (well, actually too weak before you have a notion of metric, and then too strong as soon as you imbue it with one)
My point was not that R^2 by itself sufficed
Seems only constructables are dealt with in euclidean geo
.
that's how i interpreted this
Unless you introduce some given length
Your message was interleaved between the two. Weird timing.
First comment was meant to be like "well if you get over how annoying constructing R is ..."
¯_(ツ)_/¯
then yeah you can just embed any axiomatization of euclidean geometry into ℝ²
by just fixing a particular line as length 1
this is why we call the metric on ℝ² the euclidean metric
it's the metric by which we relate ℝ² to euclidean geometry
(in a sense...)
hey
i've seen the ^ on top of the vectors to indicate unit vectors
but i'm not sure if i can use it for any unit vector, or only for the bases
what's the convention?
and a related questin , a direction vector is also meant to be of unit length?
Hey. In my university they usually use the hat convention for unit vectors in general (but only in physics classes)
r-hats are used to indicate unit vectors
Yeah
Not an expert, but I don't think so. They represent a direction in the sense than you can scale them as much as you want (to get a line) so I guess it doesn't really change that much if they have a different length
Unit vectors are used to indicate the direction of a vector. They are also called direction vectors and are of unit length. You can scale them sure, but on their own they represent unit length in a specific direction
Makes sense, at least as a concept
why to form a circle, the basis vectors needs to be orthogonal? example Acos(t) + Bsin(t) where A and B are the basis vectors
if A and B are not orthogonal i get a stretched circle
my justification, after seeing the result on graph, would be that sin and cos are "meant" to work on orthogonal basis to form a circle. by changing the bases i am deforming the space, and the circle and anything in there with it
but.. i would not have expected that without graphing it.
A linear transform preserves the unit circle iff it preserves the inner product
So the transform taking standard basis to A, B preserves the unit circle iff A, B are unit and orthogonal
so if i have Acos(t) + Bsin(t) the only way i have to check if the path is a circle is checking orthogonality of A and B?
and constant radius
Yea
is there a way to see the circle is not a circle withtout checking orthogonality of A and B ?
i'm kinda repeating the same question i guess, from another perspective
i think i am doing that.
just trying to see the problem from different perspectives
Either A, B have different lengths or they're not orthogonal
I think any method will be equivalent to checking that
could be a mix? having different length and not orthogonal results in a circle?
cause now i'm using unit vectors
No since t = 0 and t = π/2 will yield different lengths
Ig for the 2d case the check is easier, you just have to check whether one of them is the other rotated 90°, which is easy to compute in 2d
ohhh ok. this fact i think highlight another thing for me: t=0 and t=pi/2 will be on the basis, and have the length of the basis in those points. nice
this would check the lenght, right? not orthogonality
This gets both length and orthogonality
but i have to do that for all points ok, not just t= 0 and pi/2
I meant check whether A rotated 90° is B
Since the only way to get an orthogonal vector with the same length in 2d is to rotate 90° clockwise or counterclockwise
means add pi/2 offset, correct?
As in, rotating A around the origin in the usual manner
i understand this graphically
but how do i check this with math?
well no worries anyway, i'll do some tests and ill figure it out
i'm a bit hazy at the moment, need to try
If A = (x, y), then rotated 90° ccw and cw are (-y, x) and (y, -x) respectively
thanky you!!
<@&268886789983436800>
'Twas but a heart 😔
is learning the basics of number theory enough to learn modular arithmetic
you only need to know what is a fraction and what is division to learn modular arithmetic
like, the general fraction and division or are we talking about some post-calc/university stuff
fractions and division as taught in 6th grade
ok ok good.
bc i tried learning the game theory or knot theory and it was god awful i didnt understand shit
well of course because both of these have a ton of pre-requisites
knot theory isn't even taught in university
well now i will try to learn modular arithmetic and hopefully know stuff to solve problems
whoever put that shit on "ideas for your extended essay" is a menace
Do you even need to know fractions to learn modular arithmetic?
at this point I don't think it matters
if you don't know fractions you should probably learn them first anyway
Yeah. But I think in theory you could learn modular arithmetic with only knowing multiplication and subtraction, lol
Wassap losers
@drowsy talon did you get some math reading done during spring back? Or just relax?
I did a little bit of math reading. Looked through some of the books you recommended before. Finished a novel and started another one. Mostly relaxed. Did you have Spring Break too?
Yes but I was busy at work. I think spring break as actually my least productive week of 2024 so far lol
Any math books you have liked so far or disliked?
Uh oh. Thats not good. Do you do mathy type stuff for work?
I like all of them. They're easy to understand and read through. I like to read textbooks like novels too. I'm nerdy. 🤓
I won't go into specifics but no it's not math-related.
John Stillwell has a few good books, I feel he writes very novel-like.
He has a few geometry books, one on number theory, there's Mathematics and Its History
If you want to learn more about abstract algebra. Like fields and groups and stuff, but you want a nice easy read and introduction instead of a heavy rigorous math-major textbook.
He has two books that are supposed to be read together (in either order)
Elements of Number Theory and Elements of Algebra
Just curious. You seem very knowledgeable in math. Oh thanks. I'll check those out. Just don't want a dry math book that is all about history. Found a few of those before and they were very boring.
This is a career change for me
it's easier to learn something when you're interested in it vs a timecrunch and pressure to get a degree
Yeah I personally didn't care about his mathematical history one but others have liked it. I enjoy his other books though.
In theory you can learn everything about foundation/logic theory/category theory/set theory without knowing what's multiplication
Doesn't mean your should
You'd need multiplication sometimes (atleast if you want to want to do stuff like determining the cardinality of the cartesian product of two finite sets, ...) but yeah, true
Do you read novels too or mostly math stuff? What is your favorite math subject or topic?
Nope, my little free time is devoted just to math. Right now I wouldn't say I have a favorite or non-favorite. It's all interesting and useful.
Do you read alot of material on one subject and then move to another one? Or do you read alot about everything all at the same time?
Hey fellow career changer. Same!
Are you a math major too? @cunning plaza
Yep.
Oh nice. I'm not. I just like to read and study various math topics. 🤓
It is a fun topic as you go higher up
anyone knows if it's possible to pan the view in desmos3d ?
it is always centered at the origin
If you click the gear in the top right you can adjust the x,y,z bounds to move over the view
hi! im doing a project for my stats class and need answers for a survey, the answers are anonymous! i would appreciate if some of u could fill it out :D
https://forms.gle/EjTqKPUzkNRKhDdz5
done
ty!
i need to show proof for the triangle inqeuality thm for a>= 0, b<0, and a+b>=0
i said that |a|=a, |b|=-b, and |a+b|=a+b
then i said a+b<=a-b since b<0
then i substituted everything in leaving |a+b|<=|a|+|b|
does this proof work?
the answer key shows a different proof, so that is why i am curious
seems fine to me, "then i said a+b<=a-b since b<0" might need another sentence of justification though
(namely, use b < 0 < -b and add a to both sides)
Why do calculus
$
$\sum_{n=1}^\infty (-1)^n a_n$ and not $\lim_{k \to \infty } \sum_{n=1}^k (-1)^n a_n$
determinate
the former is notation for the latter
yeah make sense, you mean subtract a from both sides though right?
i mean add to both sides
b < -b implies b + a < -b + a
which is equivalent (by commutativity) to a + b < a + (-b)
oh nvm i thought you meant add a both sides to a+b<=a-b
how do I get image perms?
why do you need them?
You have to complete a dare given to you by eric
hlu!
repost if no image perms
Guys , are the calculus and similar courses on Khan academy fully complete to applies them in more advanced things ?
If fog(x) = 6x+5 and gof(x)= 6x then find g(x) or f(x)
It looks like there exist linear g and f that satisfy the system of equations
Id have to check
g=ax+b, f=cx+d
fog=c(ax+b)+d = acx + bc+d
gof=a(cx+d)+b = acx + ad+b
1)ac = 6,
2)bc+d=5
3)ad+b=0
sub 3 into 2,
-adc+d=5
-6d+d=5
d=-1
so a=b
g=ax+a, f=(6x-a)/a
Another approach
gm
chimpanzees can drink out of bottles?
lol
i guess i dont see why they cant
just never thought
that was smth they just knew how to do
i guess they couldve also been taught how to do it
HOw do I clarify to the reader that I'm plotting my plot using polar coordinates "for ease of viewing"? Idk how to write it right lol
If I just plot it as y = f(theta) it looks uggy and like a sine wave with a very high frequency (which makes it hard to read) but if I plot it as r = f(theta) it's so much easier to read
y = ...
r = ...
:D
Oh I just said "for visual clarity", that works
well i mean you could also just change the scale
I like the radial plot better
also why is the radial plot smooth if it’s high frequency
maybe i’m just misunderstanding lol
shouldn’t it also be super spiky

Idk it's just the scale that makes it look high frequency I guess
I think it's not high frequency I'm just an engineer who lost all math ability
yea i think itd probably be better to just change the scale on the x-axis, if youre trying to show the relationship between two variables y and x
but, if your trying to show a shape, that really does look like the radial graph,then its better to plot that
@mint patio on desmos if you click settings you can change the x-axis limits
Yeah I could change the scale but I like the radial plot a lot more 💀
Like this looks so clean and tells you everything you need to know
Just to be clear the plot is with respect to an angle so we're not losing information
at 0 rad E = 6 GPa, at pi/2 rad E = 6 GPa, E is maximized at pi/4 rad
HS GPAs suck ass
Yeah 6 gigspascals is pretty low
this is allowed then
pretty cool even
Is this on desmos/geogebra? And how do you get that circular graph?
It's on Desmos, you can get polar plots using r(theta) = some function of theta
For example mine was r(theta) = I1 + I2 + R1cos(2theta) + R2cos(4theta), where I1, I2, R1, R2 are constants
I am not familiar with this stuff so
You can make the coordinate system polar by clicking on the wrench in the top right
It will change the grid so it's radial and angular like in mine
Btw, do you think it's a good idea to start learning calculus fully until 2025? I am 15
Well, by fully I don't mean like very deeply, just become good at integration and derivates
Go for it
I expect you’ll struggle though
Should only take two weeks
if you smart enough then go for it
I am also learning olympiad mathematics, so calculus shouldn't be harder
calculus is just a trig and algebra check
you'll be fine as long as you're decent at that
well theres the occasional limit
any limit you'll see in calc can either be done geometrically, with properties of e, or w lhop
or taylor series
ah, l'hopital, the hammer that keeps on giving
Are proofs in textbooks actually useful?
Like, I see them but. Do the actually expect me to care or remember them?
I'm not supposed to remember this proof right?
I think Theorem 10 is more important here, 11 is just a corollary 
By the time you get gud you should be able to come up with proofs for things like that off the top of your head
that's good
proofs are understanding
if you understand this without the proof then you do not need to read the proof per se
I don't know about explicitly remembering this exact proof but not understanding the argument behind this is basically just not understanding linalg itself
although the way you phrased your message makes me think you dont understand it
since its utterly trivial.
Yes. They expect you to care. If you can't reconstruct the proof, you don't understand the theorem statement.
its not something you need to "remember"
TL;DR yes?!?!
nah theyre something added by Big Textbook Publishing to justify their $100 price tags
freely-distributed textbooks like Rising Sea famously have 0 proofs
Hey, does anyone want to correspond about data science stuff?
If I go from a community college to a university, and then I apply for grad school, will they care/look at what grades I got in community college?
For places I applied most wanted all transcripts, but some put a cap on how far back they cared about.
For the place I got accepted, even though they capped it off so that I never ended up having to submit all my cc transcripts to apply, after getting accepted they still wanted everything.
I'd say more wanted everything than not for the actual application.
got it
so would you say it is worth it to get a good gpa for humanities courses in community college, at the expense of more time spent on my math courses?
math/cs
I have required humanities courses I have to take
I mean theres really no reason to not get good grades in those
because they are in community college, not in stat uni, I was wondering if it was fine to not get good grades in them, but dooter said that grad programs look at the grades
Humanities courses are kinda free for the most part
Intro I should say
intros give me composition credits
not arts&humanities credits (for english classes)
Obviously they get more in depth and people start to care more once you delve deeper into subjects
and I'm not doing dance classes to get my humanity credits lol
what you peeps think of cantors diagonisation argument
hi
pretty cool
I couldn’t get what it means
Hello
Cantors argument
Am not
Hello
He was talking abt me
Oh
Okay so essentially, cantor says that if (0,1) is countable then there is a bijection from N->(0,1), so he assumes this fact to work on a proof by contradiction. Since each number in (0,1) has a unique decimal expansion we can make a table like this (see image) where a_mn is a digit in the decimal expansion
Now the crux of his argument was that the number with digits highlighted in bold, ie the number in the diagonal, doesn't have a n in N such that f(n)= that number, hence a bijection wouldn't exist.
why isn't terminology in math consistent?
or atleast in liner algebra
One thing can have five different names
It is consistent, there is just more than one way of looking at the same concept
what thing
I wake up at 7:15 and come back home from school at 14:20 (its shorter because of Ramadan)
I did the math and I only spend 280 minutes of those 7 hours in class
,w 280/(7*60)
Two-thirds
And I don't have recess and I have after school class, which if I didn't would make the percentage even lower.
But that's crazy
an entire THIRD of the time I take out of my day now for school is spent on morning routine, transportation, and breaks between classes
(Actually there are some other causes but their contribution is negligible)
This chat dead?
even silence is better than discussy 1

Why does this channel exist anyway?
Sending messages here is like one of those chess games where you get hours/days to make a move.
for when discussion gets too hectic
Does it ever
it does
sometimes there’s 3 convos going on at once and people will move here to continue
I always thought why thesw discussion/chill channels don't have the chat slowdown feature.
But I guess it never gets that hectic does it
i've seen more math discussions here than a normal convo
Yeah this one smells like business.
lmao
ok lol
I need to talk to my teachers so they can be a reference for my REU applications
I have nothing to talk to them about, am i screwed?
Networking is so awful
do you peeps calculus complicated or hard or something you can do with a bit of practice
like puzzles
they can be solved with a bit of effort and are also interesting.
I'm acc abt to do an optimization question rn
It's the worst tbh but that's cuz I lack doing application questions, but taking derivatives from different rules and such are nice
I liked just taking the derivatives, now it's more 😭
what is 35^214 + 124^4577?'
Y'all know geomags? I have a question about some of the mathematics of it but I'm unsure which channel to ask in
If y'all don't know what geomags are, they're a toy with magnetic sticks and steel balls
!help
To ask for mathematics help on this server, please open your own help channel or help thread. See #❓how-to-get-help for instructions.
,w 35^214 + 124^4577
7-11 near my place finally carries the strawberry monster energy drink. this is so swag
my favorite drink is GGF9000
yes
its brand new (in my part of canada) but i think its been around in the states for a while
strawberry monster is so good
sipping it rn
this shit is heavenly
had it for the first time a couple weeks ago and ive been fiending for it since
now i have 3 in my fridge mwahaha (that will last me 2 days)
my favorite drink is diet coke
my second favorite is a blend of arsenic, mercury, and wine.
that's a name of a drink?? 😭
no wonder you aren't calm, collected, or sane
we have??
did me explaining that the language center of me is an llm exit your context window?
surely it then becomes a natural conclusion that there are Q-learning models modelling and controlling various hierarchies of actions
maybe one day you'll understand smh.
but the mainstream is still using adam of all things
thankfully our in house method is vastly superior
"our" being the secret organization i run, of course
yeah, my point exactly
perhaps somebody should actually implement retrieval augmented generation on your end, huh?
at this point you are being outperformed by claude
GG® is the ultimate energy and focus formula and The Official Energy Drink of Shitposting™️. The highest quality ingredients make up an energy formula that mixes completely and provides a healthier and more cost effective energy drink. A strawberry-lime flavor developed to The Russian Badger's liking. Try the Caffeine
oh lmaoo
gamer supps no way
someone help quick cries derivative question
how tf would I derive f(x) = (cos(2x))^-3
BRAIN IS FARTING
yea mb
use the chain rule
yea but thats where my brain farts how in the fuck does that happen again
im integrating and thats what im setting as u
did you solve it
What hobbies do you guys have?
What do you think Apart from math, nothing much
Progress of grimmmet?
dawg i literally just got out of bed 2 seconds ago
also let me do this meeting in a couple mins first 
😡
i finished the (100-page) chapter on markov chains
and by finished i mean i skipped the last section and the final 50-problem set they do in every chapter 
i will go back and do the problem set at some point
I don’t have hobbies other than math
And I was looking for new ones
Same
Holy crap i didnt know its that long
yes it was fucking brutal 
110 pages
What book is that
grimmett and stirzaker
I'll read it after sieve methods
based
mfw author of my book leaving the proof of GPY sieve as an exercise to the reader
leave cutting edge stuff as an exercise
real
do i dare ask what this is

A sieve used to prove stuff about gaps between primes
GPY (Goldston Pintz Yildirim) btw
I mean I get the philosophy of the author that I need to do exercises but some of these are just crazy
who, grimmett & stirzaker?
No I'm talking about sieve theory
ah. well grimmett and stirzaker share the same philosophy lol
)



