#serious-discussion
1 messages · Page 459 of 1
verilog and vhdl are two known ones
like stuff is getting kinda small
so is there like special machines that can read the code and print the boards
oh yeah beyond 14nm across you start to have quantum tunneling problems. i mean transistors are little switches, computers run on 1's and 0's , on and off, so you have to be able to open and close the switches. there's a certain point where even when the switch is "open", the electrons can just quantum tunnel across the gap and so it doesn't look sufficiently different than a closed switch.
Another problem is that more transistors and a higher clock cycle simply require more electricity to run, which creates battery load problems. they have partially accounted this by working to lower the voltage thresholds necessary for a transistor to register a signal as a 0 or 1, maybe instead of 0 volts to 5 volts the range is like 0V to 3.3V
i don't know if the machines take VHDL code specifically, the code for hardware design languages is a bit more abstract than that. it tells you how the parts of the system fit together conceptually, not physically
i must say
these cpus
are not very right to repiar
repair*
:/
1 transistor is dead
oof
haha. they're very complicated, i don't think they're meant to be hard to repair by design they're just crazy small. i think the intel x86 has 18 parts of the pipeline
the toy model i studied in college only had like 5
to explain what i mean here
to make cpus more efficient
they need to shrink the distance between stuff?
you can think of each CPU instruction as having a couple different parts
and they have to be executed sequentially
like
"add two numbers" is like
- first, move the numbers from the registers they are stored into the adder.
- then, add the numbers
- move the output to this register
so there are really three different parts but they're all using different hardware
what's more efficient is
the metaphor i learned is like a washer and dryer
doing the laundry involves both washing and drying
but you don't have to wait till the first load is done drying to put the second load into the wash
you can have a bunch of different instructions in the "pipeline" which are all working their way through the system at the same time at different stages of completion
so you should move new numbers into the adding machine at the same time as the output from the previous numbers are being removed, and so on
as people push for more efficient and faster CPU, the pipelines get longer and more complicated
is this more so for single core performance
i mean i know you could slap more chips on something
but i guess that doesn't exactly improve certain applications
all of what i'm describing is happening is in a single core
i see
so is it possible to completely build a "computer ":... like wire by wire? Because it would be cool to understand a computer from the point of just some electrical power?
guess might really depend definition of computer and scope
oh yeah, definitely, you can make a pretty simple one
i got a great book to recommend you that explains the process from the ground up
it's called "The Elements of Computing Systems" by Noam Nisan and Shimon Schocken
when you say build does this mean using "prebuilt" chips of sorts
I'm pretty sure someone did that
well i have seen this
I've finished building and testing the Megaprocessor. Here is a short tour showing what it's made of.
(There was an error in the audio settings for the first version of this video which is fixed for this.)
Update Winter 2016:
If you want to see the machine in the flesh its now at the Centre for Computing History in Cambridge, http://www.compu...
oh no things are much easier today. i mean in those days, they still used vacuum tubes rather than transistors
transistors are extremely tiny
vacuum tubes are huge and need to be cooled
The Megaprocessor is a micro-processor built large. Very large. See and watch every detail of how computers work. And 10,000 LEDs.
i guess he built his using transistors
nice
lmfao
this is very funny
it's a bit insane to me that he built a foot long adder instead of using a 23 cent off-the-shelf adding circuit
that's like
a bridge too far for me
it's a question of understanding how it works tho like
i have no trouble understanding how I could personally build an adder for transistors so it's not "cheating" for me to replace it with an off the shelf part
right
i recommend starting with digital logic / Boolean logic. NAND gates, D flip flops and JK latches and shit like that
yeah it won't go too far but you'll learn how to store bits in memory (these are what flip flops and latches are for)
and it's not too much harder than that to figure out how to access a specific memory bank and pull a specific bit from it (or write to it)
read the elements of computing systems book it goes much further
probably should
the book for this course is
Digital Systems: Principles & Applications (12thEd.) 2016Tocci, Widmer & Moss; Prentice Hall. (ISBN # 978-0134220130)

nice
If i have a main function and another 2-3 more function, how can i compare these and find out which one is the closest (using math)
Cross correlation is one my option but i wanna hear others aswell
which one is the closest to... what?
like you mean the "main function"?
i guess it depends how you define "closest", my gut instinct assuming theyre integrable would be to take the integral of the difference
like if your main function is $f$ and your other functions are $g_1, g_2, g_3$ then minimize[
\int_{\text{domain}} \abs{f(x) - g_i(x)} \dd{x}
] and the $g_i$ that makes this minimal is the ``closest" function
Namington
this isnt quite the same measure as cross correlation mind
but its a bit simpler
cross correlation more compares the "shape" of functions rather than the "distance" between them
its more sensible for most applications
but i cant tell exactly what youre after
anybody got any advice on how i can get better at math's because i have started to like it and try to become better but there are certain questions where i cant find the solutions to
Hi thanks for the reply:
I am doing a Math paper on the Elo Rating System from chess,
I have the theoretical function that plots the expected score with respect to the differences in the player's rating. I am creating right now another 2-3 experimental function that have slightly different factors from the databases, and I want to analyze how the experimental is different from the theoretical function and perhaps see which experimental function is closest to the theoretical one
I think integration is very simple and acceptable and i will use it if i struggle to understand the mathematical concepts of more advanced areas
well its very imperfect
like consider
is the blue function or the green function "closer to" the white function?
my simple integral would probably call the green function "closer"
er wait
no it wouldnt because i was smart enough to take absolute values
...
ignore me
ok lol
namington of 5 minutes ago is way smarter than namington of right now

What are some other areas
Other than cross correlation
that u feel is fit-able according to what i want
no just basic intro to circuit stuff and some digital electronics course but i started doing some googling and ended up hearing about vhd and it being used for i guess making processors...
I'm learning VHDL currently
Assembly is horribly difficult
I don't know what microprocessor you used but I used the Motorola 68HC11
I used the TI MSP430
Well the microcontroller
I’m taking advanced microprocessors this semester and we are working with the msp432
With this robot gadget kit for the lab
I'm still using the Motorola 68HC11
You are taking a second course for microprocessors?
Just started the course
For the first one
I did the first one already, just started the second
Nope, not at all
Nope, we were given labs and was told to code
Yeah same but we had to do a final project on the microcontroller at the end
Are you a computer engineer?
Electrical Engineering
Oh nice
ODEs are so boring
In differential geometry, the fundamental theorem of space curves states that every regular curve in three-dimensional space, with non-zero curvature, has its shape (and size) completely determined by its curvature and torsion.

@velvet dagger So basically in Pure Math undergrad at UCLA, most people get shafted and only the top 1 or 2 students get attention from faculty
In applied math they have a lot of research opportunities, so the applied math undergrads usually do very well
Hmm, that surprises me a bit given the size
Like my algebra prof richard elman said he only gives out one A+
And that's the only person he can write a good letter of rec for
He told one of my friends, who was basically a prodigy in math that he wasn't good enough because his final score was like 184/270. Some kid in the class got 268/270. Before our year, the highest anyone got on his final was 170/270 for nearly 3 and a half decades
That friend gave up on algebra, devoted himself to analysis and got 3 REU papers in analysis before graduating from UCLA, and got lots of attention from Tao and Garnett
Got into every PhD program he applied to
Meanwhile in the applied math side of things, they hand out research projects and get papers out like it's candy
But if you go there and you are one of the super-star students you will get a lot of attention
I mean is Elman a special case? I know a current student who seems fine
It could be Elman was a special case
But I had him for 5 classes
As a transfer student, that kinda hurt me a lot since
Y'know I'm no super star
So maybe it's heavily skewed based on that experience, but my experiences with Garnett were much better
Yeah I think you just got unlucky there then
Gotcha
For pure math I hear UCSD does a wonderful job of mentoring students
Everyone I know that transferred there and tried
Did well
this is probably the case moonbears
there are several people who are not in the "top 2"
who are doing very well
It also didn't help that I just had a string of bad post doc teachers my first year
And I was too much of a brainlet for Burt Totaro, and Gangbo was just awful at course structuring
My second year was much, much better at UCLA tbh
I think if I had a third or fourth year there my opinion would have changed drastically
But I was too poor for that
UCLA is fine, transfers tend to have a hard time as they only get 2 years
so just one year before getting rec letters
instead of 3
A+s are hard to get
I got an A only
"only an A"
I mean, it's one of my few As at UCLA
an A is great!
Lots of +'s in the B range lol
lots of Bs as well
If I had to do it all again I think what I'd do differently is
Take 131AH in the winter quarter
Take 110AH in the first fall quarter
And still do 115AH
Maybe try to take 225A first quarter

Shoulda woulda coulda
I know a couple of transfers who had pretty good strats
one of them did the departmental scholars thing and stayed an extra year
another one just took a gap year
I think that was the right move to make
One of my friends whos still there is taking 215 now
He just did an REU in comm alg.
with gieseker?
I think so
the gieseker scommalg summer reu is pretty common
Oh no, not the REU summer with Gieseker
a lot of people do it after the 110 series
He did one at a different university that was actually funded
ah
John did an REU with Gieseker on Analytic Number Theory
It is now

They didn't start that until 2018
And nobody told me during that summer when I was doing an independent study w/ Garnett
Fkin' Connie
they usually send out an email around march
Oh I applied for the math department job opening
At the administration level at UCLA
noice
The payscale looks ridiculous
how's the texas thing going
Ok moving to dms
@fast ivy so meromorphic functions are just holo maps to CP^1
but yeah it tells you that given input you can always get given outputs
by some mero function
does foster cover riemann existence theorem?
yeah he proves it with cohomology
How far along are you in Forster?
Forster reading group let's go
nice kek
I will read this first chapter this week
And I if I have any questions I will prolly ask here lol
but yeah, it looks like a big review of the theory of fundamental groups and covering spaces
yeah kinda, altho the sheaf stuff was somewhat new to me
are the last 3 sections just riemann hilbert
i skipped section 11, but 9 and 10 are just defining differential forms and stuff
Honestly can't hurt for me lol I am rusty on some deets on pi_1 and covering spaces
But yeah def soonish I'll be good with this material
And can catch up
i'm in for the reading group on forster please tell me if there's a meeting plan
ping me
anyone doing aerospace engineering, and if so any tips for someone who is going into that path through the electrical engineering side pleading_face
🥺
Im doing aero engineering - or it's mechanical engineering with concentration in aerospace
are u a graduate?
undergrad
I have a close friend in EE grad school ,he says theres two main pathways: building circuits of actual computers or doing the E&M work of electronics
concenctration really just means "on top of"
so its ME with aerospace classses thrown in
oh danngggg
oh that does make sense
im a first year in electrical and i am a little unclear on the direction ill be taking
but taking aerospace classes is definitely something i plan on doing after covering my ge
do u have any tips - types of programs to join/ labs
You should change majors to aerospace then if possible
anything of that sort?
well i was going to, however when it comes to job search i was told itd b too focused of a major
and doing electrical/mechanical would give me room but also present me as one with a more rounded knowledge over specifically aerospace
I would explore your colleges clubs/projects, some may offer projects covering aerospace topics. For example my college offers a drone building club where you quite literally build a drone from scratch that competes against other schools. Another project is building a sattelite to launch into space, among many others
despite there being subcats within aero
see if your college has any of these types of projects within it's college of engineering
this is true, mechanical has the most "leeway", aerospace engineering will help you most get a job in aerospace (espeically airlines), electrical engineering is mainly building circuits OR programming
so if you wanna be the guy to code AI, or to build an RTX 3090 card with resistors, transisitors, semi conductors, etc, that is EE
oh that makes sense, that helps a lot honestly
i didnt rllt even know what to look for
tysm <33
and yes i was warned abt that - lucky early
yuhs 🥺🥺🥺 das actually sick so its def some im not opposed to studying
You have until your sophomore year to really decide, freshman year is mainly full of GE
yeah EE is the furthest from aero, unless you wanna like program the planes sensors etc. But EE doesn't design the plane, that is ME or Aero engineer
wait so when u say program, would that be the inner functions of a plan rather than the design of them and things of that sort
cries in lack of understanding

programming = coding
the literal if{}, then{} statements
like java, c, python, matlab, etc
ahhh yes makes sense . . .
good good, if you have any more questions about literally anyting in college just ping me
tysmmm!! can i friend u so i remember ur @
it was rlly nice talking, ill def come to ask for advice further along the line
Yeah for sure! I'll friend you as well
It was a pleasure, feel free to ask anything anytime
tysm 🥺 <3333333 too kind tt
the wording is weird but apparently the week just started
and after he is done with the day
he just throws away the shirt and tie
in a pile
its very weird
so you won't have that shirt ever again in that week
your choice of shirts decreases every day
also did discord change font?
this is fucking ugly man
I thought I messed up zoom or something
sure I won't talk about the solution but the problem is literally saying that this guy is lazy so he does laundry at the end of his week he has 5 shirts and 5 ties with (shirt-tie) matching pairs, he goes to work and chooses a random shirt and a random tie and when he returns he throws it away in laundry pile, so next day he has 4 shirts and 4 ties to randomly choose from
yeah
oh wait
there's multiple possible pairs
but they don't deepend on each other do they
you only considered 1
if you are confused about the solution and not the actual problem #❓how-to-get-help is better suited
ok
electrical engineering is a rich source of interesting problems for mathematics.
i would say that this is its primary value.
How do you get into these engineering fields as an ameture?
Breadboarding is an easy way to start off with digital engineering.
If you want to make more advanced stuff, you'll have to read more and learn more
for example you could learn to make a PID controller and program it to control a very fine tuned physical movement
$2 for 5PCBs (Any solder mask colour): https://jlcpcb.com
See each step for the P, the I and D action. See how each of the variables will change the output and finally get the ball stablea and stop it in the middle of the balance. Theory + example of PID tunning.
Help my projects on Patreon : https://www.patreon.com/ELECTRONOOBS
my Q&A page: ...
i just found this guy from a random youtube search but there's a million amateurs online posting their constructions.
I recommend reading about signal processing and linear signals and systems as soon as you have the calculus background to understand it
Ok thanks. I always felt that engineering was one of the topics thst needs lots of preparation
there is a lot of advanced mathematics under the hood but you can get away with just learning the formulas and how to apply them in a lot of situations.
the important thing is to start getting hands on experience and playing with stuff
i think control theory is quite beautiful.
it's about applying the Laplace transform to study linear differential equations and use this to design feedback loops that cause a system to stabilize around a steady operating point
yooooo the seminar is fricking dope
it will be chill, no homework or nothing. The guy has also read Hatcher and he will be talking about algtop from a cat view there too
I'm so fricking hyped lesssgoooo
Sounds cool
yeeee it does
there was a seminar this semester on higher homotopy theory
but I didn't have the prereq knowledge to go so I missed it
big oof
category theory and higher homotopy theory I think
hey can anyone tell what we do
after studying differential equations
like in high schools the last topic of calculus is differntiatial equation so what we do next if we have interest in calculus and want to study it deeper.
Real Analysis maybe?
But it really depends on what your interest in mathematics is.
In general
There's no such clear path
Of course you need to study some basic stuff to have the needed knowledge to advance
But you kind of make your own path in general
In general, people either take a real analysis course, linear algebra/abstract algebra course, basic point-set topology, complex analysis
These are all good starts
At least in my biased view
I'm not sure you actually study differential equations In high-school as in ODE's
yes bro there is a chapter named differntiatial equation in high school syllabus
in our school syllabus
Hmm OK interesting, thing is what did you like about calculus?@vale dawn
Was it the application, theory or proofs?
That will say alot about what type of math you enjoy
i think its a different field and a different
algebra is just a basic thing which we use in our daily life but calculus for me is an abstract like thing and it is also used in my favourite subject physics .
Makes sense
you can also definitely learn much more about ODEs if you are so inclined, if it's anything like what we have in the uk
ya ur education system is much different from ours
oh lol
Calculus is a great subject, because its not too abstract and not to hard to apply
But not all subjects are like that
i also want to learn because i want to learn physics of higher level which includes 80 prcnt calculus
Ok then you definitely need to learn differential equations
for physics-related stuff, looking at linear algebra and more on differential equations would be a good idea
doing linear algebra opens up more on systems of differential equations for example and helps you generalise a lot of the ideas
Yup ^
specially that integral sign gives an awesome feel while making it

Lool🤣
also vector calc
yup
^
linalg is also crucial to quantum
lol just describing first year physics maths xd
oh yeah i mean it's crucial for most physics i guess
this is also in our highschool syllabus
do you know gauss' theorem?
ya solving schrondiger equation for hydrogen like species
is using just maths like
Fourier transformation
lengendree polynomial
dirac delta notation
linear algebra
pde
etc......
that feels like the maths behind undergraduate physics in a nutshell up to GR lol
Well anyways I'm sure physics students study real analysis anyways
So that's a good idea also
i dont know much about calculus just starting it 
lol in uk idk a single physics course that does real analysis
Oh..
wait that means you haven't done vector calculus then lol if you haven't done much calculus
so yeah that's useful to learn too afterwards
just knowing basic formula using in kinematics 1d
now learning calculus for mathe
Differential equations in high-school don't always mean the same thing as ODEs e.t.c
Btw
i think ur saying right differntiatial equation are of different types maybe there is an easy one
but calculus is very interesting to explore because after highschool there are many topics to study like
multi variable calculus
PDE
complex calculus
etc .........
Ye
don't know why it feels very cool to study specially integration

gives the felling of real mathematics
and some more topics like complex no
Lol that's cool I didn't think it was that cool to study maths in hs
Haha
You need a good grounding in Calculus
adding
Well oversimplified I guess
using 'vectors' with someone not very familiar with maths can be a bit misleading since people usually learn vectors are arrows in space
seeing the theorem it looks like matrix
as in maths that's a much broader notion
matrices are one thing linear algebra deals with
lol we know vectors only this much a symbol with arrow is vector
I don't think i've ever used an arrow symbol for a vector
and I refuse to ever do that
$\vec{f}$
TTerra
thats necessary in physics
i studied it for 2d kinematics
first i thought it was a chapter of physics and used in it
then saw it in the maths syllabus
for physics i do not use arrow symbols lol
all the physics we do uses an arrow for vectors
gross
in legit everything lmao
writing arrows gets tedious very quickly
agreed
most I do is an overbar but that's usually for elements of a sequence/product space
just don't even underline/arrow them
everywhere we see arrows and arrows
no need
just use certain letters for vectors omg
i just used in physics
now when i will use it in maths
i have a question
if anybody know any trick for solving those annoying trignometry proof questions.

$\underline{x}, ,, \underset{\sim}{A}$
i have been trying to find that out myself
to no success
Ebullient Descent of Daedalus ✓
that was painful, but there
ya thats a mystery for all of us thise are the most annoying trignometry question i have ever seen
its not pain in ass
its lava in your ass

until meme geometers make them arrows in space again, except those arrows are derivations 
@forest jackal hey sorry for the ping but can i ask a question? related to what you helped me with yesterday
the vitali theorem?
idk why the lebe measure is regular
if i know this then im done i understand the proof
it's a standard result, it will definitely be in your notes/book.
i cant seem to find it 😢
okay i will just google it then i didnt know it was important
what is your book?
papa rudin
i think he does this
mid proof
of the reizs
and i checked out another proof from another source
why does wikipedia have no proof*
The Lebesgue measure is introduced in Thm 2.20 of Rudin, and regularity is stated in property (b).
yea i couldnt follow much of this theorem
Because wikipedia is not a comprehensive textbook, plenty of things on it do not have proofs written there.
regularity will be in royden too, any decent book will state it, as it is quite an important property.
whats with 2^-n in ?
is this an important idea too?
doing things with 2^-n idk i see it evrery major theorem proof
Royden section 2.4 is entirely about regularity of the Lebesgue measure for example.
well the point is in measure hteory we often build sets up as countable unions
if you are adding countably many errors together, you can't just take them smaller than epsilon and hope they converge
instead you take the k-th one to be smaller than epsilon/2^k, and then the sum of all the errors is going to be < epsilon
its important in a different way. one is a common technique in analysis proofs that is particularly useful in measure theory, the other is a fundamental property of the Lebesgue measure (and one that "decent" measures on general topological spaces should have).
Alright you fucks
Time to join voice
We're going through p-adic Kakeya conjecture
you mean regularity here
the fundamental property
right?
yes
so like
lebesgue measure is a way we like
talk about measurable sets close to like open and closed compact stuff?
like approximationm
?
I don't understand the question in that sentence.
like is regularity why we can approximate some sets
with closed and ope nsets
some measurable sets*
yes, that is what regularity is.
👍
why is this functional the riemann integral
P_ns are the set of all xs with coordinates integer multiples of 2^-n
so f is uniformly continuous cuz of some theorem in chap 4 and then
you get that the sequence for f converges
now i dont see this remark its like suddenly this is the riemann integral idk how
Pretty much directly by it's definition. But no facts about it being the Riemann integral are being used subsequently, so there is no reason to get caught up on this.
okay good
does anyone here know game parity?
I'm going to read baby Rudin

That book's gonna end this whole man's career
The first chapter of papa Rudin is possibly comprehendible
Jk it's definitely possible to read but a big shock for people who aren't used to the speed
I'm reading the first one
the every topics we study in which real no or variables are involved is real analysis or something different??
what
Idk 
Is real algebraic geometry part of real analysis?
only over R
he's asking if stuff that just uses real numbers or variable is called real anal
i think
wtf does this mean

real analysis is the study of functions that only differ by sets of measure zero
I think if he's asking if every field that deals with real numbers and real variables is called real analysis.
In that case, no.
what if you have real analysis
but instead of studying R
you study R+i
or what if you study R*i 👀
imaginary analysis
R[i] is a bad notation for R[x] which is the ring of one variable polynomials with real coefficients
(i^2+1) is the ideal generated by the polynomial i^2+1 in the ring R[i]
And the quotient R[i]/(i^2+1) is exactly the set of complex numbers

i need to learn what ideals are
like understand them and not just get a definition i forget after an hour
They’re just stuff you quotient by
yeah i don't get what quotienting is
yeah i mean like i need to learn group theory lol
Well idk then you just need to spend more time with the stuff
Are you familiar with equivalence relations?
Quotient = smush stuff together in a nice way
is this like that?
Yes
Yup
Just like that
wait really? how?
The question is just what the relation is
We don't quotient out by "bad behaved" equivalence relations, because we want the sets we are taking the quotient to still be an algebraic structure of the same "kind" after we impose this relation.
So for example
In group theory
The "right" way to quotient groups by
Is by normal subgroups
Because we can be sure
That after taking the quotient of this equivalence relation
We still get a group
In the case of rings and ideals too
The quotient has still a nice ring structure
Ninja, are you familiar with vector spaces?
nope. not at all
I think quotient vector spaces are the easiest example.
i think i just don't have enough pre req knowledge of algebra tbh
Ok, how would I say that in a grammatically correct way?
Or does that make any sense at all?
Lmao
like i'm learning a lil group theory
and i just now got to normal subgroups
and i don't understand them really
it's a weird definition
i like to think of normal subgroups as a sort of pivot
We want to impose an equivalence relation in the following manner
a group is normal if it is equal to its conjugate for every g in G
so if you think of each g in G as "permuting" G by conjugation (in fact they act as automorphisms of G), the normal subgroups are the only invariant ones
my problem is conjugation doesn't make any sense lol. feels like such a random definition
they are in some sense pivots of this rearrangement of elements of G
and quotienting by them gives you all the different ways in which we can pivot around the normal subgroup
the way normal subgroups were introduced to me is you want to define a group operation on cosets
conjugation is important because it is analogous to a change of basis in a vector space
there is really only one way to do that
and it only works if the subgroup was normal
by cayley's theorem every group is in fact a permutation group, and conjugating on a group is like changing the labelling of the set {1,...,n} that our group acts on
yeah it did remind me of that. but i don't get the connection. probably just need to spend more time learning tbh
i thought it said every group is a subgroup of a permutation group?
every group is a subgroup of S_n
$\forall g,g' \in G, g \sim_{H} g' \iff g'
\cdot g^{-1} \in H$ where $\cdot$ is the group operation on $G$.
\
\
And with this equivalence relation in mind, we also want the following properties to hold:
\
\
We want $G/H$ to still be a group under the operation $\ast$ that satisfies $[g] \ast [g'] = [ g \cdot g']$.
\
\
And we also want that the following map:
\begin{align*}
\pi : G & \rightarrow G / H \
g \mapsto [g]
\end{align*}
To be a homomorphism of groups
a subgroup of S_n by definition is a permutation group
Hmmm bad typing lol
yes it's also nice to think of normal subgroups in terms of homomorphisms
Dammnit
in particular, every homomorphism from G to H induces a normal subgroup by its kernel
MisterSystem
I think this is better now
Yeah, the idea is that normal subgroups satisfy all these properties
And this is like
What we want from a quotient group to have
[g] • [g'] = [g • g'] is the most natural operation you could ask for
And with normal subgroups
You can do this and everything is well defined
to understand the use of a normal subgroup in a way you sort of have to first understand the use of a quotient group
if you know why a quotient group is useful, and what it represents, then you should see why a normal subgroup is useful
by what MisterSystem just said
I also had a bad time understanding its importance
Number theory helped me a bit with it
i think i just need to learn more. cause this means very little to me
Because of Z/nZ
do you know what a quotient group represents
and why it's useful
no i don't
then yeah maybe spend more time on it
examples always help, as MisterSystem pointed out Z/nZ is a great example
Have you seen modular arithmetic?
In the most basic sense
It identify integers up to how they behave under divisibility by n
If they leave the same remainder under division by n
Then we want them to be "the same"
We formalize this by imposing an equivalence relation
The nice thing is that you can still do arithmetic
Even under this equivalence relation
yeah i know it
is that what Z/nZ is?
Any algebraic structure that you are interested in
Z_n?
looking at a quotient group in a sence is changing the resolution of our original gorup
by looking at different resolutions of your group, you gain a lot of insight on its structure
The / makes it clear that we are taking a quotient
and since its quotient group may be simpler to study, it's always a good idea to look at it
where subgroups correspond to zooming into your group, quotients correspond to changing the lens with which you study the group
or projecting your group
Yeah, in a sense we are studying our group up to how they behave with respect to H
for example when you look at solvable groups, just figuring out that N and G/N are solvable tells you that G is solvable
In mathematics it is very common of you to hear "yeah consider ... up to some relation" or "this holds modulo something else"
so just by looking at G at a different resolution and the lens that changes that resolution, you get a whole lot of insight on the structure of G
a simple example of this in group theory is that we really only study groups up to isomorphism
and the relation of being isomorphic is an equivalence relation
like when working with numbers, you dont bother saying if what you're counting is apples or oranges
so in a sense as long as the number represents the same quantity, it is the same, even if they may be attached to different dimensions
this is a lot less true when working in physics
it's instructive to know that in the early days of mathematics numbers came with dimensions
you never worked with a length and the square of a length (an area) at the same time
and the only dimensionless quantities were ratios
is there any like mathematical analysis of units and dimensions?
i dont think it's a field in itself but dimensional analysis is definitely a tool
it feels like something someone would have studied lol. like relationships between different kinds of units or something
units are defined precisely and very well understood
so im not sure quite what you mean
one could argue a lot of computational physics (e.g. intro kinematics) is just "relationships between different kinds of units"
This one? https://youtu.be/fo-alw2q-BU
This video has a list of books, videos, and exercises that goes through the undergraduate pure mathematics curriculum from start to finish.
LINKS:
Watch this for a flavor of what pure mathematics is like:
(Fredrich Schuller’s Lectures on Differential Geometry and Topology)
https://www.youtube.com/watch?v=7G4SqIboeig.
I watched these whe...
"differential geometry is the study of topological manifolds"
pain
topology is the study of general topological spaces which in practice are almost always spheres
how to learn pure mathematics on your own: a complete self-study guide (2913 hours of content)
insert one of those /sci/ reading guides
video 872: in this video we'll give some basic pointers about how to learn about equivariant derived categories; the next 8 videos will be about Springer theory
topology: corners suck since now i have to do homology
analysis: corners rock since now i have less work to do
manifolds with corners
exactly
they don't exist they don't exist they don't exist they don't exist they don't exist they don't exist
if math isnt real please explain the incredibly success of mathematics in convergently evolving to S^n
Spheres are the crabs of math
thinking about the hell of defining conically stratified smooth manifolds
i am convinced that no one really understands the visual intuition for gluing outside of trivial examples
they just collectively convince themselves that it makes sense
and that everyone else can visualize it so they have to to
as soon as we get past gluing cw complexes to wreaths of circles i'm fucked
this includes hatcher, there was lead in his water supply when he wrote his alg top book
how it started: vector fields on manifolds, actual geometry
how it's going: there are exactly 2880 different ways to map S^14 into S^4 up to deformation
YHH, damn it was unlisted
Nami what do you mean by gluing in this context
quotients of topological spaces
Oh
You just take the thing and you smack it on the other thing until they are one thing
i know how its supposed to work and i can visualize all the examples from an intro course
but anything beyond that
???
What even is the wreath of circles
I am having a hard time vizualizing quotient of sheaves :/
moth have you never seen how cw complexes of genus g are constructed from a bunch of circles
take a "bundle" of 4g circles and glue a disc to them
sure
i dont care what the fuck you call it
you could call it The n-th Cotton Eye Joe Space
im confused u can visualize gluing arbitrary CW complexes but not the wedge of n circles? 
its just like. n circles connected at a point
no
my point is that
i can visualize that stuff
and using that to construct cw complexes
but anything beyond that is ???
oh yeah i dont mean the construction of the bouquet itself lmao
i mean uhh
i have had a crippling fear of water droplets since i was a child
anything in that shape induces immediate panic in me
and so i have never been able to visualize a wedge sum of anything.
Relatable content

rylatable content
💦
i accidentally sprayed my family dog with a hose once and ever since she was afraid of long green (or red) things
like we had a dark green ladder and she'd run from it
Water droplets make namington sweat... But sweat creates water droplets...
Its a vicious cycle
🕷️
i wonder whether this emoji style can actually trigger peoples phobias
or if its too "cartoon-ified"
light mode users are the only one who could actually see that emoji and light mode users aren't afraid of anything

🤹♀️


👯♂️
Man in person classes is making my feet hurt so much
I didn't realize how underused they were during online learning
I'm not even taking proper classes, I'd hate to be a student walking around campus
my feet hurt for the first week
and then they got better and now i am professional walker
i must learn more from the olympics speedwalking competition.
Are bicycles allowed in your college?
in mine they are
idk about namington
probably yes also
it would be weird otherwise
Nice
why is edd muted?
I don't think bikes are allowed or even usable in our college
he replied to someone without consent
Hurb
what does hurb mean?
i think it's like "bruh" but backwards
Hurb
Has anyone used a lightning bolt as a mathematical symbol?
yeah, sometimes used as a "contradiction" symbol
i use it as a way to show harry potter fanboyism
I think bourbaki uses a lightning bolt like thing to signify a hard section
You mean this?
Z
Yeah
why do we use Fourier transforms

Because there wasn't enough transforms before

nicely explained beyond mamths explaimnation
Actually though we use fourier transforms to do useful things. I could give some examples, but that won't convey what the transform actually is
Are you seeing an application of it in class?
They sort of where introduced historically to be a useful tool
Iirc
They emerged from a work related to the heat equation
i argue fourier transforms are the only useful part of mathematics
everything else is useless
but fourier transforms are OP
The heat equation is just one of the many examples of applications of Fourier Analysis tho
@light needle does DS stand for determined by spectrum by any chance?
nope
What is it then
Ah lol
Only losers put big math words or mathematicians in their name
John DeeznutSacks
Jonathan Dee Snuts
omk thamks

so the chapters here most are from real Analysis
Chapter 1 Sets
Chapter 2 Relations and Functions
Chapter 3 Trigonometric Functions
Chapter 4 Principle of Mathematical Induction
Chapter 5 Complex Numbers and Quadratic Equations
Chapter 6 Linear Inequalities
Chapter 7 Permutation and Combinations
Chapter 8 Binomial Theorem
Chapter 9 Sequences and Series
Chapter 10 Straight Lines Exercise
Chapter 11 Conic Sections
Chapter 12 Introduction to Three Dimensional Geometry
Chapter 13 Limits and Derivatives
Chapter 14 Mathematical Reasoning
Chapter 15 Statistics
Chapter 16 Probability
this looks more like a general intro to mathematics
Do you know about calculus yet?
what's "mathematical reasoning" 
Real analysis is basically a rigorous study of functions $f : \mathcal{U} \subset \mathbb{R}^{n} \mapsto \mathbb{R}^{m}$ and as in calculus, we usually study properties of such functions as continuity, differentiability, analytic functions, integration (Riemann-Stieljes, Lebesgue and etc...)
MisterSystem
I suppose like
Intro to proofs ?

doesnt work in math either
I like the omission of "splendid" in those memes
even though it would make more sense
isn't this 10th grade cbse 
no im pretty sure i had those exact chapters in 10th grade
wait no maybe 11th?
That course layout is strange in any case
yeah im dumb it's 11th
why's it strange?
it's like a mix of a bunch of different elementary topics
think so
Its a "real analysis" course that does analysis for all of 1/16th
that's not real analysis is it?
Ie its title is just... Wrong
And no self respecting analysis course would introduce trig functions before calculus
wdym mean by
so the chapters here most are from real Analysis
I learned those exact chapters in school lol. like in that order and with those names
so i don't think it's anal
same
Yeh I would never call that an analysis course.
not even analysis
It also just seems way more elementary
An entire chapter on "linear inequalities" lmao
that list of chapters is so sulliable tbh
Linear inequalities are just linear equations with 1 extra rule
well they're a lil bit more complex than that
Well you introduce them as solutions to quadratics
And (handwavingly) note that C solved all polynomials whereas R doesn't
That's sensible if weirdly paced
It's how a reasonable complex analysis course does it
"we know going from Q to R lets us solve more polynomials, like x^2 = 2. Turns out going from R to C lets us solve even more, like x^2 = -2. As we will see later in this course, this is 'enough'; all polynomials in C can be solved in C"
Voila, there's your day 0 complex analysis motivation for C
what about polynomials with quaternion coefficients 
Now note "constructing C is just matter of affixing an element i to R obeying i^2 = -1 and letting it obey all the other algebraic rules, like distributivity"
Voila
You can be more explicit and expand (a+bi)(c+di) or whatever
But that's the conceptual guide for complex numbers
(also cover polar form ofc)
imo you need to teach the complex plane and not just use the vague algebraic explanation
polar form isn't given the attention it deserves 😔
Well sure, note that you can write complex numbers in the form a+bi for real a, b and then just represent that as an ordered pair (a, b)
not in HS anyway
And this motivates polar form
What attention does it deserve?
It's mostly a good visualization tool
well i mean like complex numbers feel much more natural in polar form than the standard form
it's almost like that's how they're meant to exist
historically it gave "philosophical justification"
it also makes it more clear why complex numbers are worth studying
they model rotation and oscillation really well
Somehow I think modern students relate more to polynomials being solvable than exp being entire
But maybe that's just me
well personally for me it didn't click until i understood how they worked in polar form. since that's where the intuition for multiplication and exponentiation is
and square roots. and basically everything else
I mean I definitely think the "add the angles, multiply the magnitudes" slogan should be given
And it's clear from polar form and Euler's formula why that holds
yeah, at least in my school that was glossed over
But in fairness, proving Euler's formula isn't super easy
You could just define the complex exponential by it
And prove it agrees with the real exponential via trig identities
you can give the intuitive explanation using derivatives
This is elementary but tedious and not particularly insightful
but at that point students havent learned differentiation
also euler's formula specifically isn't necessary
I just want polar form to be given more importance and not just treated as a side thing you can use sometimes
That's... Euler's formula
you don't need to know that it's e^i*pi
but that's the form you end up with?
yeah
What is polar form if not re^itheta
i just meant you don't have to teach euler's formula specifically. and can just keep it with trig
and not bring in complex exponentiation
not until they learn calc anyway
Teach kids complex numbers via 2 × 2 matrices 
Teach it via group actions on roots of unity
Trust me this makes total sense
And isn't at all contrived
teach it through solutions of certain cubics
since those are ones that have historically needed complex numbers to make sense
This is what I recommend for mathematically mature students
It's both the historical and modern motivation
Besides dumb signal/wave stuff that uses C as R^2 in a fancy hat
when will I be mathematically mature namington 
DN theory 
only when you master original jokes 
that was candice
then you got me
Deductive-nomological model
Dr candice dick-fit-in-your-mouth PhD
isnt nomenological a kantian term 
I blame u
The deductive-nomological model (DN model) of scientific explanation, also known as Hempel's model, the Hempel–Oppenheim model, the Popper–Hempel model, or the covering law model, is a formal view of scientifically answering questions asking, "Why...?". The DN model poses scientific explanation as a deductive structure—that is, one where truth ...
DN model

DN was gonna arrive sooner or later irrespective of you, dami
what is mathematical immaturity anyway?
dont noe
how do i go through mathematical puberty?
better be careful with the mathematical weebs
what ever i have
if only von neumann was called don neumann
Mathematical immaturity is when you spend hours arguing on math discord which notation is better
are thoe hours cumulative?
and not even bringing up Hom(•,•) the most versatile notation
but nami those people are WRONG and they need to KNOW
prefer to take the L, nami
Literally everything in mathematics can be interpreted as a set* of morphisms
*don't @ me foundations nerds
Oh no 
im not a foundation nerd, so can i @ you?

unless thats a question and not a conclusion 
sophism is when you mess up syllogisms 
hey do you guys think trig functions could have better notation
Ahem




