#serious-discussion
1 messages · Page 557 of 1
i wouldnt consider any particular irrational a "physical thing" tbh
but i think its clear to see that irrationals in general exist
at least, i believe that continua in a real sense exist
(i.e. not just as a mask for discrete stuff)
but i might be wrong there
i do not see the same connection to the complex numbers
couldnt, from that perspective, you think of the continuum as a "chunk" of a bigger object that is a bit more visible?
like how youd only see "dimensions that are not compactified" in a very very bad analogy Im making
the reason I brought this up is probably more because Im thinking of a projection or an axis than anything else
like
just thinking out loud
but consider like
a "projection" of a larger space where algebraic computations are nice
maybe thats too convenient 
anyway im not making the claim that complex numbers DONT "exist" in a real, physical sense
(i am very very tempted to make a umineko reference here)
just that you dont see them showing up as you bring in the algebra, right?
im just saying that, at least in the models im aware of, the connection feels more like a mathematical abstraction than, say
connecting continuous processes with continuums
or discrete objects with the naturals
if that makes sense
it feels we care about ℂ for some specific algebraic behaviours rather than actually feeling like it emerges naturally
maybe im just physically ignorant tho
and theres a better way to think about this
i am certainly no philosopher
I dunno
I feel like theyre so tied to summing and multiplying things
that I find them hard not to
a bit like negative numbers

¯_(ツ)_/¯
i am taking great efforts to resist the urge
its really hard to separate truth from functionality when we tlak about these things
if there even is a separation
it feels like certain constructions are more organic than others
like, certainly counting is something very tied to us
but at the same time, itd be really hard to argue that an alternative humanity wouldnt make the negative numbers or the rationals a thing
i will agree here that the complex numbers are a more organic construction
my point is that they feel like a construction explicitly
one that serves a lot of very useful purposes
but not something that DIRECTLY corresponds to anything "manifest in reality" in my eyes
you mean theyre not a feature of nature, sure
but maybe i just lack perspective
I find it a bit hard to argue for the continuum in the same sense tho
it also really feels like we are used to it
idk man
"only complete ordered field" is pretty compelling to me
since completeness and order both seem very very real
I guess you could say
if you see a bunch of things from afar, you get a blend
i guess "field" is the dubious thing there
theres no physical reason we care about "dividing" individual "points" on a continuum
so maybe ℝ is better considered as a metric space here
true
because then youre a bit forced on the concession that C almost shows up 
like hey, lets make the plane a field

yeah perhaps itd be better for me to say
i am convinced continuous metric spaces "exist" in a real sense
and i cannot say the same thing for any particular algebra on those spaces
whether that be ℝ or ℂ
true
linear thingies are easier to accept
to be clear
i would argue the ONLY natural abstractions
that are anywhere near as applicable
but still
idk
this is beyond my philosophical knowledge at this point
so id rather not say too much without having the vocabulary and context to understand arguments here
there may be people doing philosophy of math making these things a bit precise ig
I just havent looked into it
QM is very close to just like complex probability theory
if you view it in the proper way
yes
As an international student (uk) is it worth trying for some American schools for mathematics, like uc Berkeley for example, or is it just not worth it for undergrad? (I still have 2 years before I start uni, it's just I need to think about schools and admission now, and im in the uk)
How much harder is advance mathematics compared to early university
Is it just a level up and very much doable if u can understand early university or is it super hard and a lot of people struggle
what is advanced mathematics?
Anything on the advanced mathematics section on the channels
Rn im first year at uni
Think im going to start doing them next yr
Will i be okay ?
okay for what?
Like
Getting through
Understanding content
Etc
Doing well in exams
For these topics
If i put in the effort
i dont know, if you study probably ye
its not like a math degree is the hardest thing ever but you have to put in the work
what classes are you taking?
Im from uk so idk if the names will be the same
Eg my algebra 2 mjght be different to what others have
But
Next year
Im taking complex analysis fluid dynamics algebra 3 methods 3
Atleast in the first term/semester
Idk what algebra 3 is here
I think its linear algebra
well, if you are starting with proof based math then its normal that its hard
you get used to it
ye
Is there a big jump ?
many think its easier
Hmm i see
How about linear algebrs
Ive done some of it already
But i think ill be doing more next year
you'll be fine
Okok
What about probability and statistics
I havent covered them yet at all in uni
Does it really get much harder at uni ?
many think the first year is hardest
personally i didnt notice any jumps in hardness
U found yr 3 similiar to yr 1 ?
Or is it that you got better at a similiar rate to how harder things got
yes
Oh wow
thats possible
Hope thats the case for me
Hey one last question
Idk how it would be for the US
But in uk im doing a 3 yesr degree( 4 if u do a masters) so where would early university cover
Would year 2 also count as early university
probably not
I havent really covered pdes number theory or other topics as much as i see being done in thr channels
Althought i may have forgotten a bit of stuff 😅
Actually it could be a mix
i mean you wont take classes on everything
True
the channel is for open ended discussion. is this really that?
May chaos take the world 🔥 _ 🔥
compiled or interpreted programming
which one do you find better
Damnit he said "for discussion" he got us
What is the name for the specific type of vectors that are just some real components describing a position or relative position in space? Just like the typical type of vectors being an x, y, z, etc.
I guess you could call them "positive vectors", as in elements of the positive cone in R^3. See: https://en.wikipedia.org/wiki/Ordered_vector_space
I don't think it's usual to call them that though
oh nvm relative positions could have negative components too
I don't think there's an usual name since they aren't any special kind of vector, they're just elements of R^3
you could call them "position vector"
Thanks, though I didn't necessarily mean R^3, just on any R^n as opposed to some more abstract types of vector spaces
Real vector spaces?
sure, real finite-dimensional vector spaces
Nice, thanks
Is it possible to prove the inductive step of a proof by induction with assuming the negation of P(n + 1) and then proving the negation of P(n)? I mean, that's just proving an implication by proving its contrapositive.
sure
like you said it's just proof by contrapositive
applied to P(n)=>P(n+1) in particular
Cool, thanks. I was trying to prove a proposition by induction and the 'normal' way of proving the inductive step seemed so difficult, yet proving the contrapositive seems to be trivial. Unfortunately it's late at night in here, so I'll write the details of the problem and my hypothetical proof tomorrow.
me
compiled, you fucking beatnick.
interpreters are so zetta slow.

chill 😂
stop speaking like anime characters online
I'm sorry, I'm sorry. . . You're right. . .Lemme just. . hyperventilates
Alright I'm sorr- Wait a goddamn minute, aren't you LITERALLY an anime character?
not really
🧢
Java is so enjoyable
!
C# is better
arthur fist
I'm so glad this guy has me blocked
I SAW THAT
I haven't learnt it yet so i can't have an opinion on that, but i am learning C++ and i have to say, java is still more enjoyable than C++; but not as efficient
Yo, Elite math people, what do you thiink of this book : https://www.amazon.com/Building-a-Second-Brain/dp/1800812213/ref=tmm_pap_swatch_0?_encoding=UTF8&qid=&sr= ?
traitor!
Traitor alert ⚠️
What's the factorial of "traitor"

write traitor in binary then convert to numbers and then the sum of those numbers factorial = factorial of traitor?
or simply
traitor!
. . . . .
ez
I will stack smash you @echo fox
wdym


I have a question unrelated to any exercise or problems
How do I review my algebra?
seems pretty related to exercises and problems, since those are a great way to review your algebra
mhmm yes
But where do I start?
Lots of people on reddit says that a book is better, or that khan academy is better, or that a professor on youtube is better
And I'm like completely undecided on what resources to use
just pick one and use it
using a bad resource is better than not using any
and if this is high school algebra it'll all be pretty similar anyway
Mhmm
I was thinking of using a book for the exercises and khan academy for re-learning the concepts
Do I also need to revisit geometry? (I really suck at geometry)
I want to study cs at university and I've read that Euclidean geometry and Analytic geometry are required
this sounds like a good plan
and yes you'll need geometry but those weird ass proofs they make you do not really
you won't need it for alg but it's a good idea to revisit it for CS
well it depends on what specifically do you want to end up doing with that CS major
oh ok then you don't need that much
(if you did, or wanted to do e.g. computer graphics you'd have to be comfortable with vector geometry/linear algebra)
you'll still need it to pass some math courses
linear algebra and vector calculus/calc 3
I won't have to do calculus 3
But I will have to do calculus 1 and 2, and linear algebra and geometry
yeah it depends a lot on the syllabus of the place where you want to apply; sometimes it appears under different names
anyhow this sounds like a good plan if you want to review algebra
and reviewing geometry on the side would be good if you have the time; you can kinda do the same for that
I think I will also review trigonometry
I don't remember that much
i.e. watching the corresponding Khan sections and finding exercises in books
This is what I want to do
we could compile a list of exercises from books that map to khan sections
saw this on a t shirt. is this not the notation for the time derivative of i? an i with two stacked dots seems stupid
no one would ever denote this like that
so they're stacked
oh ok lol
i is essentially never used as a function in the first place
and if you're taking time derivatives and using \dot notation it DEFINITELY wont be used
because of exactly this issue
lol gotcha
we use j instead 🦾
to give food to a person is to feed
to give water to a person is to ___
wet
🤔
Flammable Math
$\dv{\dot\iota}{t}=\ddot\iota$
gmod
$\ddot\cup$
gmod
..
Is it just me or is algebra the hardest part about calculus
At least from the first 2 calc classes
Yeah that’s how it feels wish I went into these classes with algebra perfected
Feels like the people that fail calc mostly just fail algebra
And not the ideas of calc tbh
yup
this is definitely my experience teaching precalc and calc courses
the biggest difficulty is algebra and accuracy
that and people usually have a very hard time with word problems translating written information into mathematical information
Hardest class is the one you don’t understand the pre reqs fully
Fair
Since people here aren't comfortable with algebra I shall review some. Let G be a group...
topologi
\imath
$thonk(x)$
prochemist
prochemist
@leaden torrent you got a sec? I've been ruminating over what you taught me yesterday.
and I have a question.
You mentioned Mathematics is unconcerned with what is "real" , and not the job of pure math to answer questions about reality. But rather : Its job is to answer questions about math.
So, what IS math?
All this time I thought of math as something of an extension of science to explain reality. But now a PHD is telling me that isn't true and now I'm confused.
That probably depends on who you talk to
Because to me that's what it is
But I also only care about math that is imminently relevant to reality
So idk how someone who cares about "less" real math would feel about this
Okay, so question.
Is the "pure math" basically the highest level of math? And the math that is concerned with reality, i.e. relevant to reality a layer of abstraction? Or what is better named : a subset?
(or lowest level if you look at things from a pyramid perspective.)
Also, I noticed Spy x Family is on your banner. . . In case you forgot like I did, Fujimoto is back : Chainsawman returned and is uploading chapters again as of yesterday. 
Enjoy mate, that chapter was fucking AWESOME.
So awesome you posted spoilers
@neat lintel so the thing to understand here is that you can think about math at once epistemologically and at another time as a social endeavor
What does this mean?
Well, if you're trying to understand reality, then you can say that there is a "division of labor" so to speak
I follow.
For instance, say in physics, you may wish to understand a spring
In particular, you have a spring that is attached to a wall and to a weight, you pull that weight so the spring is stretched, and then let go and see what happens
After you run through the scientific method, you see that the system obeys Hooke's law
This in particular gives a differential equation, and we know how to solve that differential equation, so we understand the dynamics of the situation
This is a pretty multi step process
The physics part is doing the experiment and framing the results in mathematical language
And then once you have the result, aka the differential equation
Then you can forget that this ever came from physics
So in this way math is unconcerned with the real world: even when analyzing the real world in some capacity, what you're doing only really becomes math once you've phrased it in mathematical language and have reached the point where the reasoning you're engaging in is strictly formal
On a social level, there's a lot you can study, and people make choices based on what they find interesting
This leads to a lot of math that's inspired by science. Even on a looser level, human-performed math is going to be heavily influenced by human experience
Though a lot of times things with very obvious ties to real world problems eventually lead up to problems with less obvious ties that still garner interest
I'm screencapping this and gonna read it a few times.
tying this back to division of labor… capitalist society puts the burden of labor on the working class… and so they invest financially with hopes of return… and we can imagine the spring as investment… so then when you pull it that represents investment into workers… but then the spring gors back to equilibrium and the leaders break even… but then they force the spring into a compressed state… signifying 1) pressure on working class… 2) the rich keeping the excess profits in their pockets…

is this some joke on how sjws behave
$\text{If we have a semigroup (S,*\cdot), then we can define the subset product semigroup (P(s),\odot) to be:} \
A\odotB = {a\cdotb, a \in A, b \in B } \
\text{But we also have the semigroup (also a monoid) (P(s),\cup), which the product distributes over. Can we define some universal property from this?}$
Mizalign
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
what
why are you writing large portions of text inside mathmode
it doesnt linebreak
you also use math commands inside textmode
latex pains me
yeah
$\text{If we have a semigroup } (S, \cdot)\text{ then we can define the subset product semigroup } (P(s),\odot) \text{ to be:} \
A \odot B = {a \cdot b, a \in A, b \in B } \
\text{But we also have the semigroup (also a monoid) } (P(s),\cup)\text{, which the product distributes over. Can we define some universal property from this?}$
Mizalign
you are still enclosing text in mathmode for no reason
I mainly write shit out in another platform when I'm on my phone and copy paste it here
you should enter mathmode for math and just write text as text
and not the other way around
you enter mathmode with $ for math and once you are done, you leave mathmode again with $
and text is just text
Let $(G, \cdot)$ be a group such that...
Lochverstärker
ah okie dokie
you need a very good reason to ever use \text, mostly in displaymode
i mean its fine
idc about the statement/question
but this is/was just horrible latex
If we have a semigroup (S,$\cdot$), then we can define a semigroup over the power set of S as such:
(P(s),$\odot$) : A $\odot$ B = {a $\cdot$ b, a $\in$ A, b $\in$ B}
Mizalign
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
f a i r e n o u g h
parentheses in this case too
they are part of a tuple
which is math
sets are math, so curly braces usually are as well
you use "\{" for em right so they're not parsed as containers
alright, thanks
If we have a semigroup $(S,\cdot)$, then we can define a semigroup over the power set of $S$ as such:
$(P(s),\odot)$, with $A \odot B \coloneqq {a \cdot b : a \in A, b \in B}$.
something like that
Lochverstärker
This started because I was fucking with semigroups at work and defined something I called a "strict normal subset" which it turns out they form a fucking topology somehow
(fwiw i dont think this is interesting, its just juggling words)
I called it that because idk what else to call it
Actually just googled it
it's related to rings; it's the Zarski Topology apparently
fuck pressed enter to early
Essentially, if $(S, \cdot)$ is a semigroup (denoting the product as per usual), along with the subset product, I said a subset is strictly normal if:
- $X \subsetneq S$
- $SXS = X$
- $X \cap A = X \cap B = \emptyset \Rightarrow AB \cap X = \emptyset$
Mizalign
I keep accidentally pressing keys
if $G = (S, \cdot)$ is a monoid then $\mcl{P}(G) = (\mcl{P}(S), \odot)$ is also a monoid with $1_{\mcl{P}(G)} = {1_G}$
ally 🌈
There exists a semigroup monomorphism between em that maps each element of S to its singlet
@neat lintel won't it depend on what you mean by 'real'? In minecraft you could learn about redstone engineering, and how to make it do various things in that world, and if it's all you know, you might think of that as real. But we know that our reality doesn't have redstone, and all that exists in the game world is computed on a different sort of hardware; someone in the minecraft world may want to know about the 'lowest layer' of what they can see around them, but be off track by studying redstone
Suppose we have a random walk in 2D. The probability to go to one of the enclosed fields is 1/8. The random walk takes place in a rectangle m*n with "walls" on the outside. Does the probability of the walking person to be on a specific field converge after and infinit amount of moves? And is it independent of the starting position?
My intuition says yes, but I don't know how to prove/disprove it
Yes, it converges.
This comes from the law of large numbers
It's easier if you write the box as periodic, so that the guy teleports from one side to the other when he goes through a wall. But if you want them to bounce off instead you can use a trick called "unfolding" to turn it into the periodic case with a box with 2x the dimensions.
Hi $\mathbb{ChalkRyc}$
grass
Hello grass

Hey
Thanks a lot. I'll search it up and try to unserstand. Looking at the problem I got the result that a flat probability distribution (each field has the same probability) would not be stable. Is this correct?
Like there would be changes in probability after the next move. As the probability of being in a corner or near a wall might decrease.
Yes
OK, thx
HI RYC
(P & Q) implies P
that seems correct
if I know P and Q are both true then I should know that P is true
but what if (P & Q) is a contradiction?
(P & ~P) implies P?
That doesnt seem like a meaningful deduction.
If someone told me
"If 0 = 1 and 0 != 1 then 0 = 1"
I wouldnt understand
Its not a meaningful statement
It doesnt appear to be a valid deduction
FALSE implies [anything] is always true
but note that this "true" refers to the statement itself
not to the conclusion of the implication
this is called "vacuous truth"
you can conclude anything from a false premise
so the entire statement is considered "true"
I don't believe in Principle of Explosion
how do you justify Disjunctive Syllogism in the case of a contradiction?
How do you conclude Q from (P or Q) and ~P?
normally you wouldn't have a contradiction and Disjunctive Syllogism would be correct
but not in this case
"I have a dog OR I have a cat
I do not have a dog
Therefore, I have a cat"
I don't have a dog
and
I do have a dog
the reasoning is exactly the same
Without law of noncontradiction, isn't that a possibility?
yes
this is why contradictions are avoided in classical logic
you can apply the exact same reasoning to them, and conclude any statement.
so either you need to treat contradictions as "magically different" somehow
which implies your deductive system somehow "knows" what a contradiction is beforehand?
and that's very hard to determine in practice
outside of these simple toy examples
OR you remove these very useful logical reasoning rules
which makes your system a lot less powerful
(not to mention, no longer modelling how we actually think about things)
But I'm saying Disjunctive syllogism isn't valid if Law of Non-contradiction fails
i don't mean to say that Law of non-contradiction is wrong
but how do you justify Disjunctive Syllogism if a contradiction is possible?
but my point is that that implies you need to know beforehand whether your premises are contradictory BEFORE you do any reasoning
which effectively makes all logic worthless
since if we knew that already, why would we bother doing logic?
just take your premise and conclusion and check whether they contradict in some model
in any case, that doesnt really matter for your original question
FALSE implies [whatever] is not inherently contradictory
or anything like that
it's just... how we talk about conditions
if i say
"If x is not equal to 0, then x² is positive"
this is an implication statement
(x ≠ 0) → (x² > 0)
[here our universe is the real numbers]
and this statement is true
even if i make the premise false, say by letting x = 0
the statement... is still true
it's now of the form FALSE → FALSE, sure
but the statement itself is true
we only care about cases where the premise is true
we ignore cases where it's false, by just saying it's "true" in those cases
this is "just" a definition, but it's the only definition that makes implies actually work for what we want it to communicate
After all, if I asked you
"Prove that, for any integer x, 'x is prime' implies either x = 2 or x is odd"
your proof would ONLY consider the case where x is prime
the other cases are IRRELEVANT
so the statement NEEDS to be true "by default" in those cases
x = 9 would make this FALSE implies TRUE, and x = 4 would make it FALSE implies FALSE
the proof above claims that any statement can be proved from a contradiction
but I claim it's not valid
because it uses Disjunctive syllogism inappropriately
then try and define another system of logical reasoning where you can't conclude anything from a contradiction.
no, it uses disjunctive syllogism completely appropriately
disjunctive syllogism is a prior; it's a rule of inference
you can define a system without it
but you'll quickly realize that it makes life a lot harder
and it makes your system a lot weaker
and your benefit is avoiding counterintuitive results from contradictions, which like... why do you care?
contradictions should ideally be avoided
that is to say, if you get a contradiction, you fucked up
(well, at least a top-level contradiction)
(contradictions WITHIN implications can be useful for formal proofs.)
it requires law of non-contradiction to be valid
you don't need think of it as a "rule" of some system
it models our thinking
try to persuade someone that Disjunctive Syllogism is correct to someone who believes contradictions are possible
it won't work
sigh
i'll write a dialogue for you
to illustrate my point
if you're going to completely ignore what i'm saying, then just do more math and you'll get it eventually
it's very obvious why this stuff is the way it is once you've done proper mathematics
i challenge you to rephrase this proof of $\forall x(P(x) \rightarrow Q(x)) \lor \exists x P(x)$ without allowing a contradiction to imply anything
Namington
i believe it's possible but it'll be very difficult
but the statement itself is a triviality.
A: Disjunctive Syllogism is correct
B: show me the proof please.
A: We affirm P OR Q. And so at least one of them is true.
B: Yes
A: And we know that P is not true
B: Indeed.
A: Therefore Q is true.
B: But now I'm lost. I am a dialetheist and I believe some contradictions are true. How did you know Q is true?
A: Because P is not true.
B: But it doesn't follow that Q is true. Perhaps P is both true and not true.
A: That's not intelligible. Law of Non-contradiction forbids such a thing.
B: But how can you prove Disjunctive Syllogism without Law of Non-contradiction?
I agree. I believe Law of Non-contradiction
but why justify everything in terms of formal systems?
A: Disjunctive Syllogism is correct
B: show me the proof please.
the correct answer is "it can't be proven, it's a rule of inference".
well, more accurately
"it proves itself, it's a rule of inference"
because formal systems are ways of modelling logic
we don't have to stipulate rules
we can justify them
justify modus ponens for me.
If you know the truth of A
and experience the motion from A to B
Then you necessarily experience the truth of B
This is the symbolic form we impose on our thinking
Logic gives us a schema
so we know it's true by virtue of observing our thinking and how it relates to the symbolic form
"you necessarily"? why? what does it mean to "experience"? what is a "motion"?
this argument is not convincing to me; it seems to be based off some subjective physical experiences rather than formal reasoning
its subjective. because our subjective intuition is needed to make the symbolic logic intelligible
intuition is prior to formal systems and necessary
so you're saying that modus ponens is a formal rule developed based off of subjective experiences
good, we're on the same page
i could say the same thing about every other rule of inference.
but the point is that they're arbitrary, and you could theoretically make systems without them
look into, say, paraconsistent logic if you're interested to see what mathematical legwork is necessary to make inconsistencies work
without implying everything
but subjective experience shows (or at least suggests) that Disjunctive Syllogism is not valid in the presence of a contradiction
which makes the "proof" of Principle of Explosion dubious
paraconsistent logic DOES indeed reject disjunctive syllogism
how do you "subjectively experience" a contradiction?
a contradiction is not meaningful
it deadens the movement of thought
this is my subjective experience
??????
i think you fundamentally misunderstand the point of logic
logic is meant to develop rules and then reason about those rules
you can reason that there should be different rules
you could reasonably say that "i think disjunctive syllogism is bad because a more 'accurate' logical system for reasoning about reality ought to permit contradictions without having every statement be true"
that's fine
but it doesn't mean that disjunctive syllogism is invalid in logical systems that accept it
you're proposing that we model reality (or maybe not "reality" but some reasoning system based on subjective experience) with a different formalism
again, that's fine to do, but it's a different question
it's not logic, it's metalogic/philosophy
when we do mathematics, we almost always use the classical system that accepts disjunctive syllogism and avoids contradictions.
i'm simply pointing out that the proof fails
Law of Non-contradiction is true
and so Disjunctive Syllogism is also true
but the "proof" considers an unintelligible case where Law of Non-contradiction fails
no, the proof doesnt
so the application of DS is inappropriate
disjunctive syllogism is said to hold as a universal
regardless of whether your premises are contradictory or not
it's said to apply to ALL statements
this is a prior of the logical system.
and with that in mind, the proof is correct.
it's a bad system
you're free to think that
it doesn't model human thought correctly
but then you have to use an alternate system
well, it certainly models my thought correctly
as well as that of most mathematicians
since this system models how mathematical arguments are actually constructed
if you accept contradictions in your system without assuming they can imply anything, you have to, for example, deny the validity of proof by contradiction
that's just a very simple example
you need to make some more fundamental changes to how we construct arguments as well
the classic proof of the infinitude of primes no longer works, obviously
or the irrationality of the square root of 2
my subjective thinking has plenty of autonomy
why do we even need formal systems?
that's a philosophical question more than a mathematical one
it, at the very least, helps us communicate with others why we're making the conclusions we are
subjectivity has a lot of room for doubt and ambiguity, at least when we try to communicate our "reasoning" to others
establishing formal systems and working within those resolves that
since it's clear where each step comes from
it comes from the formal system
the formal system may or may not be "inspired by reality" or "by how we actually think" or whatever
fundamentally it's just a collection of rules for structuring an argument.
you don't NEED it, but then you're not arguing from logos anymore
which, again, is fine!
at least if your personal philosophy supports that
but it's not mathematics!
alright
Which is the channel for epsilon-delta proofs?
basic stuff: #calculus or #proofs-and-logic or a help channel
more complicated: #real-complex-analysis
Thanks
constructing R as a completion of Q as a metric space
A metric space depends on a mapping to R

There are ways to do this without it being circular
But yeah this is annoying to avoid
The thing is, the "image of the metric" is, well, the group of positive rationals under multiplication adjoin 0
you could just, define the endomorphism and go about the general definition of a metric but just adjusting the codomain
The endomorphism in particular is the absolute value which since the rationals strictly greater than 0 form a group, it's an endomorphism
I wonder if the property of the metric space itself depends on the set-theoretic structure and ordering in relation to it's operations which might carry over to just Q, or any ordered field
you know
now that you've brought it up
i never realized this

look i just want to avoid dedekind cuts okay
yeah for example when defining cauchy sequences in Q, we can use rational epsilon>0
once u have R u can show that 'rational' can be replaced by 'real'
What topics in math feel completely disjoint from the algebra/geometry side of things. Im assuming combinatorics, and logic stuff
But there are a lot of topics so Im sure I am just being naive here
actually feeling pretty content with constructing the p-adics as completions of Q now since R is a separate structure, no circularity to avoid 😌
Where were those text-voice channels…?
click this
I see, thanks it works
I wouldn't necessarily say combinatorics especially with tropical and algebraic combinatorics then there's also finite geometry, geometric combinatorics, and combinatorial geometry
Q can be false…
Does anyone know how useful going to aayjs conference is on personal statements or essays
nope
what are things that the implication ( local --> global ) does not work for?
real functions?
idk cauchy integral formula and like holomorphic functions in general seem kinda sus
so uh im not gonna have a sink in my dorm, so how tf am I gonna get drinking water? am I just gonna have to buy a shit ton of bottled water??
WTF LOL
surely there'll be one in the bathroom
are those fine to drink from??
I can tell you're not a student yet if you're asking questions like that
go buy bottled water if you want but it'll be more expensive
the no sink thing is stupid though
yeah I was thinking it would be unnecessarily expensive so idk
yeah it is
we even have communal kitchens
I'd be more annoyed by having to brush my teeth in the public restroom lol
yeah im gonna have to deal with that shit
this is gonna be a rude awakening for me
first year is always a drop in living conditions lol
2nd year sometimes is as well 
f
Hey all, new here, anyone studying discrete math?
find it difficult to study alone
presheaves
not algebraic geometry
@burnt dune start here http://mathcenter.spb.ru/nikaan/2019/topology/4.pdf
what uni
also
why are you drinking tap water LOL
UF @iron osprey
it was one of the cheapest dorms
I knew what I was getting myself into but whatever
im gonna be a freshman this fall
he has another book u can read
Elements of Algebraic Topology
oh god you're one of THOSE
(sorry. i hate hatcher.)
yea if i come to ur pad i need a filtered bottle sorry
upper class bastard get out of my house
in germany tap water has higher quality standards than bottled water
lucky you
that is not the case here 
have you tried living in a country that cares about quality of water?
but ye, i would try a water filter
smh loch
up norf it's basically bottled water but down souf it's RANK
no clue
is there no shared space somewhere with a sink
i hate hatcher too
average london resident drinking tap water
https://www.youtube.com/watch?v=jTvL4r_S2Po
I guess
what
just got this amazing email
I understood why positive * negative = negative, and why negative * negative = positive
I feel good, not great, but good lol
i dont
A small step in the right direction
think of the number line
and then think of -1 as flipping to the other side so that you are the same distance away from 0
so 5*(-6)=5*6*(-1)
a+(-a) = 0
a(-b)+(-a)(-b) = 0
-ab+(-a)(-b) = 0
=> ab = (-a)(-b)
and then you just flip across
gmod are you in boston
this is the formal approach
no
ah
im in florida
fsu?
hahyahahahhahahah
f poly?
uf
nice nice
Interesting water conversation 
Wait what now
LOL
if you refuse to drink tap water GET OUT MY HOUSE
I don't want TORIES (gmod) in my house
which one seems like something an upper class person wouldn't do
I have absolutely no idea
👂
LOL
tap water isn't the best quality water
but I guess I'll filter it and it'll be fine
Is it not drinking from it because you're being picky or drinking from it because it implies your tap water is that safe to drink?
tyr
what
an interesting quandary yess quite
I'd go with not drinking
tap water tends to be region based rather than "house price" based
I see
I have a bottled water factory set up in my backyard and whenever you use the tap some1 manually pours bottled water from the other side
I just realized
Manan.'s real name isn't Manan.
that's a nickname
their real name is Manan

Me struggling to see the difference.
Are you ok
who is exotic enough to include a full stop in their name?
Half of my full name is included.
I guess it’s bad to use real name online?

of course
irl names are big cringe
But there a billion benjr so it’s ok, I am not dumb enough to include last names.
I don’t know what that means.
it just means private info gets released publically
Yeah.
I couldn’t think of any other name lol
I would never tell anyone online that my real name is Bartholomew Geraldine IV
Ok Bart.
MOOOOOODS
you're real name can never be that cool
it's probably something lame like jeff or smth
firstly it would be spelt geoff, i.e. correctly
secondly I am not called jeff, Jeffery, or any other assorted jeff based schisms
What are you, some kind of gamer?
my full name is actually elizabeth alexandra mary windsor II
🐲
lel
Carter? I arldy knew 'er!
Carter 5
Mach 1
. . . . .I wanna know how you got to that sentence from me typing that. . . . .
And if your answer doesn't please me, this puppy gets it.
true gamer moment
Oh yeah? Well, you're a hyperbolic paraboloid.
my name is indeed big cringe
maybe even bigger cringe than most
but hands down, all irl names are cring
no exceptions
period.
mine isnt a name
it will be a title in the near future
just you wait
just you wait
I think "Raghuram" is a pretty good username
true
Yes sister period 
It’s always funny when I see people say or write that.
Full stop

what makes you think I'm a girl?
Not assuming, just what comes with the saying “period”.

periodt.
Terminally online teenage brainrot
but you can NOT prove me wrong on this
Irl names are definitely not cringe
Some of us pick good online names
But definitely not all of us
Saying "all names ever are cringe" is like, peak brainrot
I can't prove you wrong because there is no universe in which you are even close to right
you don't believe this
would you change your name to DarQ irl?
sometimes i wonder if the internet would be better (or worse) if we were forced to use our legal names
I could say no
butdoublingdownwouldbefunnier
so yes
absolutely

I only use my illegal name
I would use my middle name but it's against the law
use your mothers middle name
Are you serious?
law of excluded middle 😭
Turns out names can be illegal.
lol
lmao
mero rly waited an hour and a half for that lmfaoooo
#serious-discussion being dead as always
Who said the quote that involves digging to find the gold
Hey
Ie doing examples?
How do I prepare myself for 11th grade?
What are the topic one learns for math at 11th grade ?
depends really
@neat lintel calculus and linear algebra and stuff
What did u learn in 10th grade
I had a kind of shortcut tbh
And I didn’t go to a real 10th grade school
But now at 11th I will do
Last year I was very neglectful and so on
They say it’s going to be hard at this school
So I want to know what I have to expect
you can always review your algebra and trigonometry stuff
At most review ur precalculus stuff
dont think u will do anything higher than calc at 11th grade
No
Functions?
calculus is finding rate of change of a function and area under a curve
yea sorta functions
derivatives and integrals basically
Considered algebra
You mean it’s kinda interconnected with algebra?
No its just algebra
Unrelated: what considered means in that sentence?
I meant that doing linear and quadratic equations is algebra
Ahh I just noticed which one you have replied to
Thank you 😊
I have an idea now
no problem
Lotta studying
Wdym?
Learning Calc
Im at UNI rn and catching up on Alg/Calc along side calc
Didn’t care in HS but my major is pretty math heavy 😅
Degenerate
90% sure this diverges
the numerator is less than 2(n!)
so the series has an upper bound of 2
For some reason I thought the sum of factorials had a closed form
that was something like (n+1)! + something
But that was $\sum_{k = 0}^{n} k k!$
pairo
naively I'd guess 1 but could be wrong, just based on it being 1 + 1/n + 1/(n(n-1)) + 1/(n(n-1)(n-2)) + ... + 1/n! and guessing these extra terms after 1 go to 0 in the limit
what's $\lim_{n\to \i} \sum^\i_{i=1} \frac{1}{n^i}$?
DarQ
that's a geometric series so you could evaluate it
that's a geometric series lol
yeah that's 0
so $1 + 1/n + 1/(n(n-1)) + 1/(n(n-1)(n-2)) + ... + 1/n!<1+1/n+\sum^{n}{i=1} \frac{1}{n^i}<1+1/n+ \sum^\i{i=1} \frac{1}{n^i}<1+0+0$
DarQ
I think your inequality is backwards since 1/(n(n-1)) > 1/n^2
I see I didn't look very closely at what you wrote, I think your upper index on your sum should have been n-2 then, not that it matters much but that's all I looked at originally and assumed you were comparing them that way haha
nice I guess you solved it then
I think your upper index on your sum should have been n-2 then
I knew it was wrong but I didn't want to think about it too much
yeah once you go to the infinite sum doesn't matter anyways lol
I guess you can notice that the sum of 1! to (n-2)! is bounded by (n-1)! (since each term is less than (n-2)! and there are less than n-1 terms) and then the numerator is bounded by 2(n-1)! + n!. Then the 2(n-1)!/n! part goes to 0, so you're left with n!/n! which goes to 1.
That's an upper bound on the limit, for a lower bound throw out everything besides n! on top. that also goes to 1.
So the limit is 1.
@bright hill
I still dont understand this. Sure, 1/n is above 1/n(n-1), but why is 1/n^2 above 1/n(n-1)(n-2)? And so on
In particular, I am skeptical that n^(n-1) is less than n! (It's not).
Good problem though.
I remember a fun one that felt kind of like this
I'm have some trouble with this, I'd love some help! Thank you
@hollow sundial You're not a helper anymore? 
hellllsssss nah
it was a fun six months, but i didn't like all the entitled people and daily occurrence of new people abusing pings among other problems and doesn't seem like anyone's trying to solve it.
You were a helper for 6 months?
six months
my condolences
And I know, people can't read how to get help properly, ever
lol i just said the same thing to someone else
yea i don't know how to solve this problem. there's nothing disincentivizing people to not break rules if that gets them help faster and enough helpers are curious/kind enough to help despite people asking break the rules to get help in the first place.
Prime example #help-15 message
lol #help-15 message
i admire @tiny forge and @storm sage since they seem to keep an even keel
other people too. usually why i rep helpers in #bots. there's absolutely nothing benefiting to being a helper so i give imaginary points
I just do it for fun
you and @tiny forge are always patient
I only answer ones I feel like
I'm patient to an extent, only when people start questioning everything, I get annoyed
like i can't do anything algebra related
I get annoyed too but I don't help while annoyed
yea i can relate
Like if people understand the concept fully, then they question the final answer. Like bud, if you applied everything I stated and typed it in a calculator properly, 95% of the time it's correct. Like why are you questioning?
like eric helped this person i was trying to help, but they needed extraordinary amount of explanation, so eric shoo'd me away which i appreciated. but at the very end out of nowhere decided to shit on me and other people before him.
yea I was annoyed by that
i knew i should have blocked earlier
but I didn't want to start about it
take the high road 
stay innocent, young one
insult block and never interact with again
nah I don't do that
i wish i blocked before helping them so far only for them to disregard all of my effort
I don't recall if you were suffer in the background with me, when someone could not do basic multiplication. Now that was annoying
I usually just try to empathize
I know what it feels like to not understand something even though it feels basic
i feel like this has happened more than once 
so I just picture myself from that perspective
and then ask what would be helpful to me if I were in that situation
and then whenever I get frustrated I just say I have to go and someone else can probably help
Lol
i applaud this self control
Or when I tell people Google exists, and people should utilize it. Like formulas. People come here, asking for a formula, and the first thing I tell them, is google it
To me, yes. But what about you?
using google well enough to get a meaningful result is a skill some have yet to develop
oh to me? i don't think anything as basic as multiplication, but maybe something like adding and multiplying fractions?
But if someone was looking up the formula for compound interest or arc length. Simple things to google and you need zero skills to do that
Sometimes when someone tells someone to google something, it is just condescending, so I try to soften the tone
unfortunately there's a lot of b.s. math "help", particularly at the lower levels, on random internet sites. the situation is not quite as bad as it is for programming, but it's not great
some people are just afraid of trying things
this is why i do not bother with most channels
I meant the fact that people can't do basic multiplication, did that experience happen to you too, or were you referring to all my experiences you witnessed?
damn me telling people to try anything is like 10% of my suggestions
Unironically; I think emotional support is a good skill to have
for my advisor it's like 75% emotional support
People like you tropo, det, chmonkey and stuff in the advanced channels are like most of the reason I'm here.
Math help is more like 25% math help, 50% emotional support, and 100% people cheating on tests and quizzes

I mean if they're obviously cheating then just don't help them
i do remember reading you helping people with the very basics. i never struggled with multiplication myself.
I usually assume good faith
hello my ears are burning
i would probably go insane if i tried to help in something like #calculus or the basic help channels. for my own sanity (and learning!) i keep it to a select few
I message modmail or ping mods right away. Mainly message modmail so that way people don't run when I ping mods
as a masochist i will say that the helpers role looks unbearable to have
eh it's fine
I like being able to jump into the help channels and help when I feel like it but I don't think I'd want the pings. 
you can just ignore the pings that you don't want to help with
Yeah true 
i'm definitely the opposite.
but you still get the ping
that just makes things more combative
I can definitely how there is a pipeline helpers can go through where they end up bitter and horrible when helping lol and I don't blame them, I just try stay out of it
which makes you more annoyed
I turned the pings off immediately lmao
indeed. i only lasted 6 months. i didn't optimize for the long term metrics
And also, when people don't do their research, and it's a concept I'm too lazy to teach, like point slope or something simple where there are tons of videos, like khan or organic chem tutor, I always link the video
Sometimes it's like a kid, where obviously they haven't done any research but I don't feel like I can blame them too much for it. 
I had this save
@hollow sundial you became very efficient at linking people specific websites for their needs
yeah linking the video is a good approach
i'm always down to add extra details to videos, but no one seems to want to watch them in the first place
LOL I told someone not to ping helpers role until 15 minutes passed and then they dmed me and called me a c*** (racial slur)
I was laughing so hard
thanks. it became muscle memory
Like what effect did they think that would have
!15m
Please only use the <@&286206848099549185> ping once if your question has not been answered for 15 minutes. Please do not ping or DM individual users about your question.
PSA that this exists
oooh
scares them
damn way to overachieve
they should skip @Helpers and just ping @everyone
Let's see
@wild lantern !15m
you'd be surprised how often they try
Nope
Ah dang
!15m @hollow sundial
Please only use the <@&286206848099549185> ping once if your question has not been answered for 15 minutes. Please do not ping or DM individual users about your question.
O i c
wdym
@here @everyone @Helpers @ModMail @Moderators @neat lintel PLEASE HELP ME WITH MY HOMEWORK IT'S DUE IN TWO MINUTES PLEASE HELP
how do i remap @helpers to @tterra
i never thought about doing this
I mean I think being inviting is half of the job of helping, if you want to help condescendingly then maybe it's just better if you stay quiet because that can damage a person's attitude toward math permanently
being inviting?! shit i'm just trying to explain math
You tend to be super patient.
i think this is definitely my issue, at least half the time.
being condescending to someone who is themselves condescending is very fun though
I'm just trying to not lost braincells with the stupidity
it kinda has to be an effort on both ends, us as helpers have to be patient and understanding, people looking for help need to at least put in some effort and use their initiative
thank goodness someone else notices besides me. i thought the new level of being a normal human was @storm sage and i'm not ready to make that leap
Yes there should be an effort on both sides definitely
I have this too

