#serious-discussion

1 messages · Page 503 of 1

raven haven
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groups too?

modest rune
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I think you are conflating different usages of the word closed

pulsar bane
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When you say "closed" you have to say what is closed (i.e. operation)

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Yes, vector addition, multiplication, and scalar multiplication are closed but that's not the same as closed algebraically.

raven haven
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both of them, vector addition and scalar multiplication

modest rune
#

Yes, vector spaces are closed under these properties

raven haven
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how come

modest rune
#

Definition

pulsar bane
#

For an operation + to be closed it means ∀a,b∈S, a+b∈S.

modest rune
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In fact, I would argue that if you define these things properly the word closed is simply redundant

raven haven
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no i mean how come they're not algebraically closed

modest rune
modest rune
pulsar bane
modest rune
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most fields are not algebraically closed

raven haven
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i see ok thanks

sick burrow
#

bruh

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in class rn my prof is trying to parse a homework problem that he literally wrote for this week

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someone asked him "wait how do I do this" and now he's rereading the problem to remind himself how it works

cinder flume
#

You can define a vs such that the element satisfying root not be there

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Sorry if the conv Changed

sick burrow
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it has been 20 minutes and he's still working out the problem catThink

limber thunder
errant furnace
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you guys are probably stressing him out

steep mountain
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is that weird ?

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my professor once forgot a certain solution to a problem and we went on to prove it together in the next ~25 mins lol

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it was very productive and idk if he did it on purpose

fair mural
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james new pfp hmmCat

steep mountain
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oh ye im just messing with my friend who dislikes anime for a bit lol

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ile go to old one later

fair mural
sick burrow
modest rune
steep mountain
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ye that's fair enough , you can't keep up with every single problem all the time.

potent aurora
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hey, I was in help room 12 and it just disappeared, can't find it among occupied, available or hidden, what do I do?

tall badge
potent aurora
#

thank you very much

fathom tendon
#

why is the discord server picture a coffee mug thinkies

pulsar bane
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Cuz' donuts, y'know.

sick burrow
#

coffis

terse flax
compact tartan
wispy dune
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does anyone have a link to the stackexchange thread that was pinned to one of the analysis channels long ago

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i remember it was a really difficult problem on polynomials and compactness(?) where some dude said it was a problem from a first year course in calculus

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even though it very clearly wasnt

limber thunder
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I think the solution involved Baire's theorem or smth

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and the guy had misread the quantifiers and it became trivial if they were like, the other way around

hybrid rune
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Sorry to intrude but my brain is a bit off today. Do you guys what is meant by evaluating this integral? The context is a grad real analysis course and no helpers seem to be available.

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$lim_{n \to +\infty} \int_{0}^{\infty} [(nsin(x/n)/((x^2+1)x))]$

fathom swallowBOT
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chernberries

limber thunder
hybrid rune
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I’m in help room 22 if you want to see my attempt

limber thunder
#

using e.g. dominated convergence thm

hybrid rune
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Yeah I’m not sure of a canonical way to find the right function that bounds f_n

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I’m pretty sure I got it; just let F(n) = that integral, take the derivative then use DCT

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Have to use MVT somewhere I think

real canopy
#

i need people to study with. but all my friends dont care abt their grade cuz its senior hs. is there anything i can do

rotund steppe
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hire a tutor KEK

neat lintel
#

are you a graded module

neat lintel
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Because better acceptance rate?

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Yeah??

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If you choose a big major with limited classes then theyll always pick the guus with 95% average over someone with 70% average

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In uni?

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College?

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??

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For better acceptence rate in the later schools?

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I just said it

deep mango
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not every country runs on the same application timeline as the US...

cyan goblet
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go to a local library when you study

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and sooner or later if you see someone who you think would be fun to sit next to

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walk up to them and ask politely if you can sit next to them

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and just study

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and once they leave be like "hey id like to get to know you" or something

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be like "im looking for a study friend" or something

compact tartan
carmine geyser
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guys simple doubt :

{0,1}^4

is it true that above notation means lot of sets with 4 elements in it ?

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like :

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{1,0,1,0},{1,0,0,0},{1,1,1,0},{1,0,1,1} etc

empty stratus
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Yes

carmine geyser
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thanks bro

empty stratus
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It's the set of al length-4 sequences of 0s and 1s.

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Good.

rotund steppe
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you want us to design your experiment for you ?lol

frail sail
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use DISCORD!

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literally so many study grps

carmine geyser
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A = {ω ∈ Ω|(ω1, ω2, ..., ωn) ∈ A(n)}.
i am confused on what this set looks like

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anyone please help

alpine kindle
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you could also describe it as the set of all functions from {0,1,2,3} (the set notation for 4) to {0,1}

carmine geyser
alpine kindle
#

that was in response to your previous question

carmine geyser
alpine kindle
#

people will be able to help you much more easily if you learn it

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it's not very difficult

carmine geyser
proper patio
stray kite
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does there exist multivariable complex analysis

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f : C^n -> C^m

ripe wasp
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hm

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is there an n- dimensional calculus

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like calculus i-ii covers 2 dimensional mostly

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calc 3 covers mostly 3 dimensional right? or is this where n- dimensional is covered

stray kite
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lol what opencry

toxic schooner
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and yes there is n dimensional calc

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probably even infinite dimension

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idk

stray kite
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how do you only learn 2d but not generalise that lol

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how do american calc courses work

neat lintel
toxic schooner
neat lintel
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Upto Calc 2 then?

stray kite
toxic schooner
pulsar bane
deep mango
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in one of my classes we just started using all the calc 3 theorems in R^n instead of R^2 and R^3

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and it was just like

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ok, i guess all that shit was the same in any dimension? but no one ever mentioned it

mellow moon
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Curl operatorS in n-dimensional setting sotrue

deep mango
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😌

neat lintel
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i want a cool partially ordered field that isnt R or C with usual orders

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?

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thatd imply 1<=0

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i asked for a ordered field not for a field with a order in its underlying set

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kid are you kidding

bronze pelican
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Check out real closed fields

fair mural
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superreal numbers

tender grotto
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what does it mean if something is closed

neat frost
tender grotto
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whats the difference

neat frost
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tbh thats not even true

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its when its complement is open iirc

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idk havent taken topology yet

modest rune
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Oh the above image

tender grotto
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well in general ig

modest rune
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it means many unrelated things

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But in this context I also have never seen this usage of closed

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@bronze pelican

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Do you know?

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My guess is that the closed here refers to "closed under the first order properties of the reals"

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but thats not very good

devout nacelle
modest rune
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I read this

modest rune
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but this does not explain the usage of the word closed

modest rune
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in particular the only other usage of closed on that page

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is to say that the real closed fields are not algebraicly closed lol

modest rune
bronze pelican
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I think model theorists just wanted the abbreviation RCF to rhyme with ACF which stands for algebraically closed fields

modest rune
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cursed

tiny marten
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this is why i do analysis

stray kite
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are all global extrema which arent at endpoints of a continuous function definition also local extrema?

surreal sapphire
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why the endpoint condition

stray kite
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cant have local extrema at endpoints can you

surreal sapphire
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why not?

stray kite
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arent they defined on open interval subsets of the domain

surreal sapphire
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yes

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but e.g. [0, 1/2) is open in [0, 1]

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anyways, i think if you use sane definitions global extrema are also local extrema

stray kite
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ok youre right idk why i thought that then lol
anyway ty

median zinc
rotund steppe
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I actually understood lecture today happy

long matrix
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$(\exists l\in{lecture})(l\in{things understood})$

fathom swallowBOT
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Shuri2060

long matrix
#

👀

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${thingsunderstood}\neq\varnothing$

fathom swallowBOT
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Shuri2060

long matrix
#

👀 👀 👀

crystal raft
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What is the criteria to be a helper?

mint patio
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Literally none

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Just ping a mod and ask for the role

crystal raft
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Ah cool

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@compact tartan could I have helper?

neat lintel
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imagine wanting to be an helper

median zinc
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Wow just directly pinging mnoop

neat lintel
#

i have cancer ok

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be careful with what you say

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i can explode

mint patio
compact tartan
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I don't mind

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if it's not annoying

midnight iron
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how could we use Bayes' Theorem to analyze situations when the sample space is partitioned more than once?

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phrasing this question to make it look right took a lot of time btw

neat lintel
tender musk
wanton tartan
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Is there any standard variable when working with quaternions

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Like x for reals or z for complex

sleek wing
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I've seen q used

wanton tartan
#

Makes sense

solar hound
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What facts should I add to the site?

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My goal is to make every number have interesting facts about it.

frail sail
charred mortar
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How many numbers are you adding in any case

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Like are you stopping at 500? 1000?

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Wikipedia has some properties of the lower numbers which could be useful as a starting point

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Although later on it peters out (see 502 = 2 x 251)

midnight iron
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I think that's the best I can do. anyways, it was just a curiosity. maybe as I learn more and more of it, I will get the answer by myself.

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thanks Todd

inner finch
edgy tartan
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what are kinds of functions that f that after dividing by x i can find inverse function explicitly
i mean inverse(f(x)/x ) exists in symbolic form

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?

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(ping if answered)

dawn sluice
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I enjoyed answering the homework question so much. Is there any platform where you got paid for tutoring?

mint patio
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I dread data analysis

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I hate doing things

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I love learning things

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Hate doing

charred mortar
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Learning is doing though

toxic schooner
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also wait, is that u in ur dp?
u look cute stareFlushed

neat lintel
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so you can do less and learn more

mint patio
mint patio
solar hound
charred mortar
#

ah auto-generated

solar hound
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But some parts of it are customized for specific numbers

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Like divisibility tests for specific numbers are customized

charred mortar
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I'm assuming stuff like factors or whatever can be automated without too much trouble

solar hound
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Yep

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It even looks in the OEIS for sequences containing the number

charred mortar
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that part's pretty cool

solar hound
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@charred mortar I'm trying to find more facts about numbers to add to it though

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Like more tests I can apply to see if the number has any other interesting properties

charred mortar
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I still think you could search wikipedia's list of properties for low numbers, like say 6 or 12, to get some ideas

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and probably have those properties apply to most of the integers in some fashion

charred mortar
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Ah well I guess a number theorist would be able to provide better answers

solar hound
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One of the things I want is more tricks

charred mortar
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I’m not one unfortunately

solar hound
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Like the sum of three palindromes one

median zinc
#

Is it JS driven?

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If the facts are generated I hope they are done once then stored in database, then perhaps verified once and then called as wanted

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You might want to RNG at either the server side or client side to vary facts shown

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Could be more interesting to not mention 1729 as a taxicab number to some visitors

solar hound
solar hound
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but if you mean manually verified that would be very tricky

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since there's so many numbers that would get random visits

median zinc
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Would be good to at least verify some of them, or you get 57 being a prime

solar hound
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It does a full prime factorization before identifying if a number is prime, so it's thorough

solar hound
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That's true, I should add taxicab numbers lol

cyan goblet
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does the equation below 5.14 denote

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$\Re(Ce^{i\omega t})$ or $\Re(C)e^{i \omega t}$

fathom swallowBOT
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anamono

cyan goblet
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i assume the latter because C is defined as a complex number?

sly vale
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since C is complex I'd assume Re(entire complex number)

compact tartan
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same

analog salmon
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who tf decided to have reduced and irreducible not mean the same thing in algebraic geometry

mellow moon
#

PROPAGANDA² this

toxic schooner
neat lintel
#

small thing

neat lintel
#
Hui and Grigor are going to play a game with the following rules.
(a) Hui begins by placing a knight on any square of a regular 8 by 8 chessboard. Grigor moves the knight first. 
(b) Hui and Grigor alternate moving the knight, but they can only move the knight to squares that it has never been to before.
(c) The player who cannot move the knight anymore loses. With the correct strategy and perfect play, either Hui or Grigor will always be able to win. Who has the winning strategy?
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i need a hint

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a small one

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anyone??

odd narwhal
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We don't really have a channel where game theory fits well

neat lintel
dry pasture
tender musk
#

@solar hound Are you done with your website and can you send a URL if you are?

tender musk
solar hound
#

I still think it needs more

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Before I can confidentally release this version of the site

tender musk
solar hound
#

But I still don't want to release it until it's 100% polished

tender musk
solar hound
#

If you want, a previous iteration of the site is available, but it's no-where near as good

solar hound
solar hound
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But this is the previous version

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It's not the remade version I'm working on

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The new version will be so much better

tender musk
solar hound
tender musk
solar hound
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Sure ig

cyan goblet
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when is $\phi$ vs $\varphi$ appropriate

fathom swallowBOT
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anamono

cyan goblet
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because (as far as im aware) i have yet to see phi denote anything other than some variable

deep mango
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Meh, interchangeable

cyan goblet
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dammit

deep mango
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Angle, homomorphism

cyan goblet
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oh true phi is angle

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forgot

jolly tulip
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@cyan goblet different notations are basically picked according to conventions and preferences. Just be consistent and do not mix them together

cyan goblet
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kk

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same thing for $\epsilon$ and $\varepsilon$ too then?

fathom swallowBOT
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anamono

deep mango
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Umm

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I would just never use epsilon and always use varepsilon

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Tbh

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Absolutely only use varepsilon for your usual small epsilons

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Some people forget to and they are evil

cyan goblet
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oh

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i dont wanna be evil

coarse grotto
deep mango
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I define \eps as a macro for \varepsilon

cyan goblet
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would i be stupid to just renew command \epsilon to \varepsilon

deep mango
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Thats fine too

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I just use a lot of epsilons so i want it shorter

cyan goblet
#

dope ty

fluid rapids
#

very good video

deep mango
gritty copper
vast surge
dawn bridge
#

i clicked

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@fluid rapids what's this

neat lintel
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just another troll vid

bright hill
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how do you guys take notes? (especially when self-teaching)

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if you don't, why?

fluid rapids
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every time you learn something try explaining it

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and word it so that you can fluently explain

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this proves mastery

bright hill
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that actually the reason why I take notes

potent valley
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I feel like notes never work for math

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like ever

surreal sapphire
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i dont write notes, but i do scratch work

fluid rapids
deep mango
#

Mathematician Moon Duchin answers the internet's burning questions about mathematics. What actually is an algorithm? Is it possible to explain Pi (π) in words? Is geometric group theory just Anabelian topology?? Moon answers all these questions and much, much more!

Still haven’t subscribed to WIRED on YouTube? ►► http://wrd.cm/15fP7B7
Listen ...

▶ Play video
bronze pelican
#

I love how this sentence is in the video description of a WIRED video

deep mango
#

lmao

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it's actually a very fun video

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if you're expecting nothing of any depth

ancient flame
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lmao

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she didn't even explain pi

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"ratio of circumference to diameter" is not mentioned at all

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like why is that not the first thing you say

hybrid rune
#

Is folland good to prepare for QR exam in real analysis?

bronze pelican
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They just took random questions from quora and stuck them in the description

deep mango
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lol

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those were literally tweets in the video

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(including the anabelian topology one)

bronze pelican
#

Ok didn't get to that point yet

empty root
#

Does anyone know why the line integral definitions of divergence and curl aren't taught often

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I think they're far more intuitive and don't depend on your coordinate frame (this is particularly important because you learn curl and divergence in so many different coordinate frames).

mellow moon
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But yes

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The same goes for surface integrals (Stokes theorem)

empty root
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We have some slighly non rigorous proofs for divergence and curl tha work wihou differential geometry

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t on my keyboard has broken

coarse grotto
# hybrid rune Is folland good to prepare for QR exam in real analysis?

my uni uses folland for the real analysis course meant to prepare you for the qual. I would say that it prepares well (but this is university dependent)
I’d say picking up something like royden or stein-sharkarchi might help you if you see a concept in practice exams that isn’t covered in folland

tiny marten
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yeah folland is used here too

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and people advise stein and shakarchi, etc

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i think that one rudin text does both too

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i used it a little for my complex analysis class

limber thunder
uncut socket
#

@austere hazel Kinda wish people would look up resources on stuff they don't understand first, because I literally Googled "point slope to slope intercept form" and that was one of the first results

austere hazel
#

google is by far a very uncommon common sense skill, i've found

uncut socket
austere hazel
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yes, yes they do

uncut socket
#

Literally all my solutions, I Google first

hybrid rune
#

My university also uses folland but I don’t like it

neat lintel
#

but sometimes people want to be told by a person rather than read and it’s understandable

long matrix
#

The mysterious thing is the process of reading still occurs via discord

frozen merlin
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so that I can look up a theorem in my 5-page book of theorems instead sifting through the of the 50 pages of the book/lecture notes, where most of the space is filled by explanations/examples/proofs

ripe wasp
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i write notes

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down of formulas and ideas

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but mostly its just to get the topics into my head

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i literally never look at them again

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after writing them

rancid meadow
#

i dont know if it is wireds fault or the presenter but god nothing of substance was said

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didnt even explain pi bleak

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yet wrote down that awful looking identity

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odd behaviour

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all the comments that are like "im a math major and this is so true sotrue" make it worse

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also opening with that clip of her being like "you don't need this" bleakbleakbleakbleakbleakbleakbleak

ember fog
#

Hello I'd like to ask for tips on dealing with math anxiety, I just read a report on it and it seems I perfectly fit the bill. Any recommendations on starting my journey? I mostly have to do it alone without the help of an educator. I feel really intimidated and scared and I know it's ridiculous.

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I really want to love math but fear is overshadowing it

rancid meadow
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idk i think its bad if u r in an authroity positon to say that without any qualifiers lol

neat lintel
#

hi

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i just opened up a poll and asked people to pick a number from 1-10

fair mural
neat lintel
long matrix
#

-9

sly vale
#

Given discussion, dx kekw

long matrix
#

dx < 1 rip you

sly vale
#

1.000...001 then 🙄

fair mural
#

1+dx

long matrix
#

1-10 is -9

sly vale
#

Yeah

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r/woooosh

fair mural
#

shut it shuri catFone

long matrix
#

1 < -9 < 10

#

ig

sick burrow
#

The only people who haven't struggled with math are people who've never seriously done math

steep mountain
sick burrow
#

So when something isn't making sense right away or you're struggling to solve a problem, don't beat yourself up about it

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Because that happens to literally every person who studies math

ember fog
#

I'll try my best to rethink how I deal with struggling, all my life I've been in a top class with super smart kids and things just came so naturally to them. Wasn't far off that I thought I was failing for my pace

#

I also thought only smart kids like them could do it

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I've been trying to use math this way, I'm redirecting my impulses towards learning math

steep mountain
#

well im sure things come more naturally to terrance tao than to me when studying analysis but thats just a depressing way to move forward and enjoy things in life

sick burrow
#

My take on talent in general is that the most significant "innate gift" for a pursuit you can have is enjoying it

steep mountain
#

i think its very natural to feel this way and i feel this way too sometimes but you have to realize that there is more important things to focus on for your own well being

#

if you feel sad by someone being better than you math is not it
there is people here in hs who are already better than me lol

sick burrow
#

The way to get good at anything is by practicing it a lot, and the main obstacle in the way of practice is it takes a lot of time and it's tedious as fuck if you don't enjoy the thing you're practicing

steep mountain
#

just find what you enjoy about math and focus on that
thats how you build passion about it

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and as he mentioned

cyan goblet
#

so in my experience the environment of "i need to match the super genius kids around me" tends to lean someone towards the "nonstop study to catch up" kinda thing

steep mountain
#

practice makes perfect

cyan goblet
#

which then is flawed because

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when you nonstop study, your efficiency actually goes 📉

ember fog
#

Fuck

cyan goblet
#

so then even when you indulge in something interesting, you have that same pattern

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so take breaks and explore other hobbies too

ember fog
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I've spent my whole life in that latter group :')

cyan goblet
#

for example, i like to do gardening

sick burrow
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imo the main thing that the "talented" people have is they really really like the thing they're doing

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So they spend a lot of time on it

cyan goblet
#

so when i've studied for a while i'll just go outside and touch some dirt or someting

sick burrow
#

And get a lot of value out of that time since they really enjoy it

cyan goblet
#

so you can focus on math if you'd like, but be sure to enjoy a lot of other things too

steep mountain
#

ye he is right
if you're passionate about something you'll probably do better than most people 95% of the time lol

cyan goblet
#

that way youll develop a healthy relationship with math, with your work ethic, and with yourself

sick burrow
#

And that time commitment is what ultimately matters more than any "innate ability"

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So the takeaway here

steep mountain
#

i made that number up but you get the point

ember fog
#

I want to fall in love with math but it feels like I've gotten on the wrong foot and have a wrong view on it, hence the fear

sick burrow
#

Is that if you care about being good at something enough to put the time it, you will get good at it

ember fog
#

Yes i love his channel

cyan goblet
#

3b1b does a good job at illustrating the beauty of math

steep mountain
#

takeaway is do it with passion or not at all

ember fog
#

I'm really inspired by him, he's the reason why i want to relearn and confront my math anxiety

cyan goblet
#

dope, then the next step would be to slowly start introducing yourself to new math concepts

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or relearning ones that you may not have a clear understanding of

sick burrow
#

Or to put it another way, the mentality of "I want to do X but I don't have the talent for it" doesn't make sense because wanting to do the thing is what talent is primarily made of

cyan goblet
#

i am being extremely realistic

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by saying that you cannot achieve perfection through nonstop study

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and will instead hit burnout

sick burrow
#

I think anyone can be really really good at almost anything if they put the time in to practice

cyan goblet
#

time commitment yes, nonstop commitment no

ember fog
#

That's kinda what I'm scared of finding out, what if math isn't the right fit for me

steep mountain
#

what most people seem to forget about einstien and newton is that

cyan goblet
#

and im not saying this person has to go and become the next einstein or newton

ember fog
#

Me giving 100% into doing it

steep mountain
#

they really loved physics lol

cyan goblet
#

im giving them a chance to just discover something new

cyan goblet
steep mountain
#

there is a reason they invest that much time into it

cyan goblet
#

and there's a lot of things outside of math that may be something you love

sick burrow
#

Some people have insane gifts, but the only thing that kind of gift lets you do that you can't without it is become one of the best in the world

cyan goblet
#

and it won't be a matter of "you weren't born with great math skills", it's just that math isn't a great fit for you

sick burrow
#

With the right amount of luck

cyan goblet
#

and that's okay

steep mountain
#

i'd like to believe its just that they are "born different" but they simply had passion and some talent and they worked hard to improve upon it

cyan goblet
#

i would love to do wildlife conservation but i tried volunteering at conservation centers and it wasn't really my thing

#

so if you've got the free time, go out and explore math

#

and if you like it, great

#

and if you dont, it is what it is

#

if you decide that math isnt for you, you will walk away with a valuable lesson

sick burrow
#

There's no point worrying you're not Euler if you aren't aiming to be Euler

cyan goblet
#

you won't have "wasted your time" pursuing something you wanted to get better at only to discover you dont like it

#

you will have instead learnt the lesson that sometimes you have to test the waters before you dive into them

sick burrow
#

The takeaway here

#

Is that there's no sense in worrying you're not "good enough"

steep mountain
#

the only reason you need to do math is to love math

sick burrow
#

Because you are good enough at math to be however good you want to be

ember fog
#

What if I learn to love it so incredibly much but my skills don't fit to do it

sick burrow
#

I'm saying that is nonsense

cyan goblet
#

^

steep mountain
#

i 2nd that

cyan goblet
#

there are plenty of ways to reach a goal if you truly love it

#

kinda why this server exists imo

ember fog
#

That's reassuring

sick burrow
#

Loving it so incredibly much is what it means for your skills to fit to it

cyan goblet
#

this is a nice little video

ember fog
#

6 hours

cyan goblet
#

10 minutes long, and pretty good

sick burrow
#

I wish I could study for 6 hours

ember fog
#

I can do all nighters when I really need to but i know that's not healthy

steep mountain
ember fog
#

Oh oops i havent tried doing math for 6 hours but in general for school i do 6 hours of self study

cyan goblet
#

adding onto what james said

sick burrow
#

What are you taking rn james ash

cyan goblet
#

over 50% of incoming students to harvard's CS department walk in with no prior experience of programming

#

actually i think it's greater than 50

steep mountain
#

metric spaces ,bilinear algebra,probability,calc 3, intro graph theory, odes

sick burrow
#

Ok but also Harvard 🤮

steep mountain
#

yes in 1 sem

sick burrow
#

Holy

#

Is this the not liberal arts college experience

#

I've never taken more than 2 math classes in a semester

steep mountain
#

lmfao its not pleasant but i manage

charred mortar
#

Yeah that is fast

#

I feel like that’s a fairly universal experience tbh

#

The more in-depth you go the more you realise how much there is to really know

steep mountain
#

indeed

#

gotta love the aha moments

deep mango
ember fog
#

Thank you everyone, truly. I'll keep trying. I hope to fall in love with math as I learn more about it.

deep mango
#

the best part about math is the grueling parts

#

when i'm having fun, something's wrong

stone valve
#

does anyone have any good resources on 3d vectors

#

coz im struggling a bit to learn it properly

#

a yt playlist would be v helpful

cyan goblet
#

video library talking about vectors and matricies in 3d space

#
  • some other stuff
deep mango
#

computations build character

stone valve
cyan goblet
stone valve
#

oh

cyan goblet
#

perhaps some linalg books?

errant furnace
stone valve
#

hm ok

#

??

neat lintel
wise vigil
wise vigil
daring zinc
#

anyone here bilingual?

devout nacelle
#

Yes

surreal sapphire
#

not being native english speaker moment

devout nacelle
#

I don't really know if I qualify as bilingual

ripe wasp
devout nacelle
#

Since I still have to use very limited amount of English off screen

surreal sapphire
#

hm?

devout nacelle
#

But my primary forum for interactions has been screen for a long time

#

I mean

surreal sapphire
#

bilingual means you speak two languages

devout nacelle
#

I don't really "speak" English a lot

surreal sapphire
#

certainly you are able to

devout nacelle
#

Verbally bleak

#

I'm definitely okay with text

surreal sapphire
#

ok, i have no idea what it means to 'speak' a language

devout nacelle
#

monkey Yeah at least for my CV I can pretend I'm proficient with English

surreal sapphire
#

when the interviewer switches to english mid conversation

devout nacelle
#

Interviews for internships have been an actual metric for me to gauge how far I can hold a conversation in English

surreal sapphire
#

its really weird for me to talk english with other germans

#

im rather comfortable talking english but i never know how much they understand

devout nacelle
#

Aah

surreal sapphire
#

it was super weird in school

devout nacelle
#

I just start supersonic rapping in English

#

With the onus to understand on the listener

surreal sapphire
#

time to go to the US for a year

devout nacelle
devout nacelle
#

:

toxic schooner
#

manan no

#

fuck off

#

😭

#

tho i would say u are ok at speaking in english

devout nacelle
#

"okay" might be a fair description, yeah

#

I still feel some nervousness meddles with what comes out of my mouth

toxic schooner
#

its pretty diff with me

#

i start speaking and then i start stuttering coz my mouth cant keep up with my head

surreal sapphire
#

you will learn quickly once english is the only way to communicate with people around you

toxic schooner
#

and then i get nervous

#

i can usuallly overcome it, but at times it becomes blobsweat

surreal sapphire
#

my final highschool year we visited london and some guy in my class was robbed

#

and unable to talk with police or wtv

#

so i had to do it

toxic schooner
#

Ooo

toxic schooner
#

talking with natives is a good way to learn

devout nacelle
surreal sapphire
#

ye, there were almost no natives in london opencry

devout nacelle
#

Lmao

surreal sapphire
#

i asked two shop owners for the phone number of the police

#

they did not know

devout nacelle
surreal sapphire
#

i asked a "policeman" giving tickets to cars

#

he gave me the wrong number

devout nacelle
#

Bruh bleakkekw

surreal sapphire
#

so yeah, this was quite the odyssee

devout nacelle
toxic schooner
surreal sapphire
#

anyways, in the end we had to visit the embassy

#

and this dude had to finally talk with someone

#

and he talked in really not great english

#

and the other guy noticed and told him to just talk german its fine monkey

toxic schooner
surreal sapphire
#

moral of the story: look after your belongings in foreign cities

#

and learn english

toxic schooner
toxic schooner
#

will be good to go

devout nacelle
surreal sapphire
#

no idea

#

my guess would be no

#

if you are nice you can probably get hold of one who speaks english well enough

#

there are lots of people in germany not being able to speak (any) german

#

problem is they dont speak english either

velvet dagger
#

What do they speak?

neat lintel
#

russian ?

#

some arabic speaking minority too afaik

flat harbor
#

wendish

velvet dagger
#

Makes sense

flat harbor
#

tongue of the wends

velvet dagger
#

Actually... idk if this is in Germany or Austria

#

But apparently there's a rarely spoken language called kandis (spelling?)

#

Oh I think it ends with eszett

#

kandiß

flat harbor
#

whats

velvet dagger
#

And it's in Austria not Germany

#

@flat harbor hmm?

neat lintel
#

why are you reacting with random emotes

velvet dagger
#

I don't know

#

Shawshank do you know of that language?

neat lintel
#

i dont

velvet dagger
#

You seem... more familiar than my American ass

flat harbor
#

then you should ask what kandis is

velvet dagger
#

Ah

flat harbor
#

go ahead

velvet dagger
#

blo what are you doing

#

I don't get it

#

Anyway Shawshank wanna know about it?

#

Bruh what's with this memeing

neat lintel
#

about kandiß ?

velvet dagger
#

Yea

neat lintel
#

sure

velvet dagger
#

Kandiß dick fit in yo mouth

I'm sorry opencry

flat harbor
#

yooooooo

velvet dagger
#

Witness the master at work

flat harbor
#

immense pain in my lower intestines

velvet dagger
#

Anyway my degeneracy aside what's up? I haven't seen you around the server much before Shawshank

#

What are you interested in?

neat lintel
#

I am new here yes, i came here initially to get help with finite automata concepts here

velvet dagger
#

Oh nice

#

I should know more about mathematical CS tbh

neat lintel
#

yes im interested in CS too, low-level concepts

toxic schooner
neat lintel
#

not strictly CS actually

#

more on the applied side

velvet dagger
#

Shyshu you actually inspired one of my better jokes

#

You remember that one time we were having the convo about Jotaro?

toxic schooner
#

the gnome one?

velvet dagger
#

Not a DN joke I mean like

#

The antagonist in Jojo

#

Loooong time ago

toxic schooner
#

i dont really remember no

velvet dagger
#

Oh

toxic schooner
#

my memory is filled with random ass chemical equations i cant remember stuff well

velvet dagger
#

Well you know that scene where he's walking to that other guy?

#

I forget his name

#

But he's like oh come as close as you want

neat lintel
#

i randomly asked here about anyone knowing haskell, someone pointed towards mniip and i saw his github and now I randomly ask about binary exploitation stuff from him in #chill

velvet dagger
#

You're the one who showed me that scene

toxic schooner
#

are u confusing me for someone else

velvet dagger
#

I mean neither have I but that famous scene with that one guy

#

Anyway so

toxic schooner
velvet dagger
#

It's a 3 part joke

#

First you ask them to translate "God" into Italian

surreal sapphire
velvet dagger
#

The goal is to somehow build up to a convo about how French numbering makes literally no sense

neat lintel
#

sababa

surreal sapphire
#

there is a german-russian minority too but its not that many

velvet dagger
#

ANd get them to say "dix neuf" (the number 19) in French

toxic schooner
velvet dagger
#

Aka deez nuts

velvet dagger
#

But you have to build up to it so it's not sus

#

So here's how it would look like, let's say I'm the one getting you here

#

Shyshu how do you say "God" in Italian?

toxic schooner
#

dio

velvet dagger
#

Dio like deez nuts

toxic schooner
velvet dagger
#

FUCKING SUBVERTED LET'S GO

toxic schooner
#

thats really nice lmao

neat lintel
#

its borderline offensive

toxic schooner
velvet dagger
#

Hmm, inappropriate I'll grant, I hesitate to say offensive

#

But wow I had to work really hard for that one there

toxic schooner
#

i knew u were building up to a deez nutz joke the moment u said god in italian

velvet dagger
#

Tru hence why I was hoping that you'd think it'd take longer by telling you the punchline

#

Reverse reverse reverse psychology

toxic schooner
#

i chose to go for it, coz i would feel bad for not letting u have it KEK

toxic schooner
plush cloud
#

i have kinda dumb question but want to see ur answers

#

not homework related

#

but math related

#

if there is infinite numbers between 0 and 1, how are we able to reach number 1? when all decimal places are resetted to 0

#

like numbers would be 0.xxxx where x /= 0, but then all xs will become 0 when it reaches 1?

#

that means the infinity numbers between 0-1 came to an end?

charred mortar
#

We can’t really “reach” 2 in that sense

#

There’s no notion of “the next number” once we introduce decimals, as far as I know

plush cloud
#

i meant 1 instead of 2 sry

flat harbor
#

real numbers dont rly exist

plush cloud
devout nacelle
#

I can write 1 and "reach" 1 in a sense

#

You most certainly can't start "counting" from 0 and reach 1, enumerating each real number in between

plush cloud
surreal sapphire
#

i dont see how this is an obstruction

#

you should be more worried about the fact that all the numbers between 0 and 1 exist

plush cloud
#

whats the first real number greater than zero

surreal sapphire
#

first?

plush cloud
#

the first real number to satisfy > 0 condition

surreal sapphire
#

there is none

devout nacelle
#

There is no such real number

#

Suppose x were to be such a real number

#

Then x/2 would be less than x and still greater than 0

#

Contradicting the fact that x was the "first" such number

plush cloud
#

im so confused

devout nacelle
#

It's okay, the idea can take some time to absorb

#

If you like to think geometrically

#

Your "first" real number would come to the right of 0 on the number line, right?

#

Now since these two points are not one and the same, there's some distance between them

plush cloud
devout nacelle
#

Pick any point lying on this segment

#

And you now have a smaller number

devout nacelle
ripe wasp
#

it basically means for any number you choose as close to 0 as you want, you can always choose a number closer to 0

plush cloud
flat harbor
#

real numbers are supposed to not make sense if u try to count them

plush cloud
#

i think its existence cannot be understood without understanding zero

flat harbor
#

thats why theyre literally called uncountable

long matrix
#

someone drop the tortoise paradox here

#

or was it hercules

plush cloud
#

😭

flat harbor
#

bb ub but if the turtle can always b bhh b then how can hercules win ?.?/??

surreal sapphire
#

the tortoise paradox is not about uncountability

devout nacelle
#

I can assure you the way real numbers are "constructed" is consistent and devoid of paradoxes as far as we know, but it takes some technical machinery to understand how they come into being from simpler numbers (rationals).

flat harbor
#

its abt misinterpreting the idea of tasks

surreal sapphire
#

the error is assuming that a sum of infinitely many numbers is necessarily infinite

long matrix
#

and more about how an infinite number of points have finite measure

abstract mason
#

@rationals have that property too right?

surreal sapphire
#

there isnt really a question here tbh

abstract mason
#

oops. newbie here. i meant to sddress sean

devout nacelle
#

I think I can vaguely sense the problem here but can't give an explanation unless Lam is familiar with limits

flat harbor
#

the concept of Convergent Sequences did not appeal to the common greek

long matrix
#

that paradox would probably

devout nacelle
#

Maybe Lam wants to think about discrete jumps starting from 0 that will eventually lead to 1

surreal sapphire
#

there is some problem, but i think lam just needs to think a bit more, identify their issue and come back then

long matrix
#

clear some things up

surreal sapphire
#

people unloading their knowledge will be semi-helpful

flat harbor
#

if smth just doesnt feel right and is very confusing

devout nacelle
#

Yeah, fair enough

flat harbor
#

smtimes helps to just put it on the backburner

devout nacelle
#

Throwback to me realising Cantor's proof of uncountability of reals actually makes sense months after seeing it for the first time

flat harbor
#

i had a crisis abt epdel the first time i learned it for abt a month

#

came back to it after a year and it was a lot clearer

#

bc of the simple fact that the more ukno the more u see

devout nacelle
#

My epdel crisis will never end

flat harbor
#

it will end once u actly commit to finishing ranal

#

stop being so math promiscuous

plush cloud
#

is 0 a part of 1?

ripe wasp
devout nacelle
#

"part"?

abstract mason
#

intersecting conversation. so there is not a way to explain this without getting deeper in more advanced math? btw hello, i just joined and know some calculus and some discrete math.

#

interesting

devout nacelle
#

Hello K-Son!

flat harbor
#

hello ❤️

plush cloud
#

can number 1 exists without 0s? for me i think 1 is the sum of zeros like 0.x + 0.y = 1

flat harbor
#

ure not talking in a way that makes sense

devout nacelle
#

Exist in what sense?

plush cloud
devout nacelle
#

I can declare a set {1} and say 1 exists (foundations cranks please steer clear of this remark)

flat harbor
#

read some stuff on how the reals are defined

#

and try to pick up how math ppl express it

devout nacelle
#

holds the urge to rec Tao's Analysis 1

flat harbor
#

mana

#

i will commit extrajudicial violence against u

surreal sapphire
#

just historically the invention of 0 comes (way) after the invention of 1

#

the number 1 is just some abstraction of a collection of 1 thing

devout nacelle
#

Good point

flat harbor
#

u just need to broaden ur idea of what "number" means

plush cloud
#

alright my head is heated, that’s enough math for today bye!

flat harbor
#

finally

devout nacelle
flat harbor
#

take some rest pal

toxic schooner
bronze pelican
bright hill
#

fuck that actually makes sense

frozen merlin
#

(for me)

somber abyss
#

u just need to know how to apply a theorem in our school, they give u the formula for it in a formula booklet

frozen merlin
somber abyss
#

thx

frozen merlin
#

if you're doing a maths course then you'll probably want to know the exact statements + proofs of the important results for the exam, but while you're learning it's very normal to forget these things

bright hill
#

do you think knowing how to replicate those proofs correctly is important for a self learner?

frozen merlin
#

depends on the theorems, sometimes a proof is really central to the idea

#

also depends on if you're learning maths for its own sake, or to apply to something like engineering

bright hill
#

I see

#

thanks for the insight!

modest rune
#

The big ideas might inspire you when it comes to proving other things, and the details you can always look up

#

But if you don’t know the big ideas, you might not even think to look at them

hollow flame
#

ive always wondered... properties that are inductively demonstrated to be true in finite cases, why does that not necessarily transfer to infinite cases?

ancient flame
#

because infinity behaves weirdly

hollow flame
#

i can maybe understand for uncountable infinity

#

but like..
if you have a normal number in a given base, right? youre guaranteed to find every sequence of finite length somewhere in its decimal expansion

modest rune
#

iirc normal is about the frequency with which the digits appear

devout nacelle
modest rune
#

not the guarantee that every finite pattern shows up

#

you can have very regular normal numbers in that case

#

am i misremembering

hollow flame
#

normal and transfinite then

#

not transfinite

modest rune
#

Transfinite?

hollow flame
#

transcendental

#

like, what we assume to be true of pi

modest rune
#

I don't think that is strong enough to guarantee what you want

hollow flame
#

because yeah if thats the definition of normal then some fractions are normal

#

"If a number is normal, no finite combination of digits of a given length occurs more frequently than any other combination of the same length"

#

from wikipedia

tiny marten
#

normality is an interesting property, i usually think of it dynamically

hollow flame
#

thats literally the definition

#

maybe this was a bad example lol its the first one i thought of

#

how about like literally anything from group theory

#

like idk fundamental theorem of abelian groups

#

not that you can do that inductively

modest rune
hollow flame
#

i guess

modest rune
#

Let A be a finite set. Then A has no proper subset of cardinality A. Proof: supposing this is true for sets of cardinality n, assume a set B of cardinality n+1 has a proper subset S of cardinality n+1. Then we may remove a point from this subset from B, and we will have a set B-x with a subset S-x both of cardinality n and with S-x proper

#

Therefore no infinite set has a proper subset of the same cardinality (which is a contradiction)

hollow flame
#

i mean at that point you may as well just appeal to like

#

zfc

modest rune
#

?

#

those are both counterexamples

#

they aren't even that complicated

#

If you want the real reason this works

hollow flame
#

that you cant construct a set containing itself as a proper subset, thats a consequence of the literal definition of a set

#

as distinct from a class

modest rune
#

That is not what I did

#

In ZFC every infinite set has a proper subset of the same cardinality

#

For example, you can remove 1 from the natural numbers

#

you still have a countable subset

#

but its proper

hollow flame
#

oh i misread

modest rune
#

The real reason this does not work is that an inductive proof gives you an algorithm to get a proof of the fact for any fixed n by just starting at the base case proof and working up

#

This terminates and therefore gives you the desired proof

#

There is a process called transfinite induction that can be used but it requires an extra step to get around this issue

hollow flame
#

makes sense

#

i think maybe invoking like zenos paradox makes it clearer

#

like i wouldnt say that it terminates

modest rune
#

terminates was a bad word to use, the point is you have some way to "get at" each n

#

whereas you can't "get at" the infinite case

hollow flame
#

but that an infinite number of finite steps will not "reach infinity"

#

you need additional machinery, like a limit or an infinite set

modest rune
#

that is essentially how the transfinite process works

#

You have two things to show, namely that if the statements holds for a then it holds for a+1, and if it holds for all such a then it holds in the limit. then you can reach all the desired ordinals

alpine kindle
#

you can reach every ordinal

#

i think

hollow flame
#

what about the smallest ordinal that is not the limit of a countable collection of ordinals

alpine kindle
#

isn't that omega?

#

because N isn't finite

hollow flame
#

oh right

#

how about countable

alpine kindle
#

uh

#

hm

untold sapphire
#

this would be the first uncountable ordinal

#

omega_1

hollow flame
#

i guess it would be the supremum of a collection of countable ordinals

#

i guess im imagining that there must be some level where transfinite induction would break down because you need a meta "all such a" sort of thing

#

but not necessarily, if its general enough

modest rune
#

every ordinal is either a limit or successor

plush venture
untold sapphire
#

this collection itself is necessarily uncountable btw

hollow flame
#

right

untold sapphire
#

of course one doesn't have to choose a countable increasing sequence of countable ordinals to take the supremum, one could just take the set of all countable ordinals and take its supremum, it's not necessary to "get there" with a countable sequence

tiny marten
#

the magic of the supremum

hollow flame
#

but you do need a set

untold sapphire
#

ya

hollow flame
#

so you couldnt take the supremum of all ordinals

untold sapphire
#

no way jose

hollow flame
#

which i guess is obvious lol

untold sapphire
#

Well you can read this the other way too

#

your argument proves that the ordinals don't form a set

#

because suppose they were a set; then you could take the supremum, and this would be an ordinal greater than all ordinals in the set, a contradiction

tiny marten
#

$sup_{\omega}{\text{all ordinals }\omega}=X$

fathom swallowBOT
#

LoLDongs

tiny marten
#

boom

#

got any other problems for me

#

just solve for x

#

something something, supremums always exist

hollow flame
#

oh thats why i said you cant take the supremum

#

because the ordinals dont constitute a set

#

how else would you arrive at "you cant take sup(all ordinals)"

untold sapphire
# hollow flame how else would you arrive at "you cant take sup(all ordinals)"

Well, what I think you're saying is

  1. The ordinals don't constitute a set.
  2. Therefore, it doesn't necessarily make sense to take the supremum of the class of all ordinals.
    And what I'm saying is:
    Hmm, I'm not convinced; how do you know that the ordinals don't constitute a set?
    Well, you can prove it by running the argument in the converse direction.
  3. If a collection of ordinals is a set, it has a supremum, which is also an ordinal.
  4. But the collection of all ordinals has no supremum. Ergo, it is not a set.
tiny marten
hollow flame
untold sapphire
#

(I guess the larger point here is that I don't know how to prove "the ordinals don't constitute a set" without assuming "every set of ordinals has a supremum", but I do know how to prove "every set of ordinals has a supremum" without assuming "the ordinals don't constitute a set")

hollow flame
#

no cap

sick burrow
#

I mean the set of all ordinals would itself be an ordinal

#

Since that's how ordinals are defined

#

But then it wouldn't contain itself

untold sapphire
#

Sure, one might assume that for the sake of a contradiction.

#

(Here I am assuming that "being a set" is part of the definition of an ordinal.)

sick burrow
#

I mean is that not just a proof that there is no set of all ordinals

#

I mean also if there was then couldn't you use that to get $ZFC \vDash ZFC$

untold sapphire
#

Yeah, you're right.

cinder flume
#

I got to the conversation just right now

fathom swallowBOT
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Worst Geometer NA

untold sapphire
modest rune
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So the issue I think is that if one constructs the ordinals in a reasonable way (say, VN ordinals) then you observe that you can take any set of ordinals and union them to get a new ordinal that is no smaller. You also observe that the successor operation is necessarily larger. Then you assume you could take the union of all ordinals. Then this is a new ordinal, larger than all others. But that ordinal +1 is larger, which is a contradiction

cinder flume
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Is the question to prove that there is no universal orjinalini set?

hollow flame
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something something too large to be a set

untold sapphire
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You can edit your posts nevzat. Haha.

sick burrow
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iirc

untold sapphire
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Yes, this is known.

cinder flume
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Isnt this burali forti paradox that you guys are talking about

sick burrow
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So if K was the largest ordinal then that would give you the set of all sets

cinder flume
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Again, I got to the convo late

sick burrow
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Hence set model of ZFC within ZFC

untold sapphire
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Yes, it's closely related to that nevzat, but each person here is I think bringing their own comments and questions, there's no one single issue to be resolved

sick burrow
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Or really just whatever contradiction you want to derive from the set of all sets

untold sapphire
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Assuming one takes Godel's incompleteness theorem and the apparatus of model theory for granted

sick burrow
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Yeah

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There are much easier ways to form a contradiction from the set of all sets

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Just comprehension into Russell's Paradox for example

hollow flame
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i was about to say

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you dont need to assume godel

sick burrow
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The godel thing is somewhat intuitive to me though

untold sapphire
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Sure, whatever floats your boat

sick burrow
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Because of the whole inaccessible cardinal giving you a model of ZFC thing

hollow flame
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wait back to the sup thing how would you show that the class of all ordinals does not have a supremum

sick burrow
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Add 1

hollow flame
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would it just be like
because the sup would have to be in the set?

untold sapphire
untold sapphire
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Her name is Summer.

tiny marten
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summer is a good pooch

neat lintel
limber oracle
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who's more of a daddy

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newton or euler

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i say newton but my friend says euler we're in an argument

static loom
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euler was legitimately a dad, newton never had kids

limber oracle
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whattt

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well imean euler does defo look like a dad

charred mortar
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Newton was kind of a huge dick from what I’ve read about him

fair mural
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yeah

little vine
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Newton said on his deathbed his greatest achievement was dying a virgin