#serious-discussion

1 messages · Page 149 of 1

solar hawk
#

Long can be good long can be bad

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Clearly

tawdry pecan
#

amukh discovering british people for the first time

fresh comet
#

who doesnt say epsilon naught

visual breach
#

Well anyway

solar hawk
#

NULL

tawdry pecan
#

epsilon naught

fresh comet
#

it didnt say curls, it said "looks"

solar hawk
#

NILL

visual breach
#

Ahhh

fresh comet
tawdry pecan
#

you are naught correct

fresh comet
visual breach
#

“That looks like plane”

fresh comet
#

0 is not okay

visual breach
#

Now it makes sense

fresh comet
tawdry pecan
#

you are now

#

sorry

fresh comet
#

i guess canada used to be a british colony

solar hawk
#

Wait

fresh comet
#

so close enough

solar hawk
#

Americans say

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epsilon “not”

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Right

fresh comet
tawdry pecan
#

yeas we dont say epsilon nut

solar hawk
fresh comet
#

ok i'll stop sending my terrible handwriting here

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i don't think i need to convince the world more about my doctor handwriting

tawdry pecan
#

i am well and thoroughly convinced

solar hawk
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LOL

sturdy gulch
#

i just came back to look at this
i feel bad for whoever needs to read this like its literally hieroglyphics

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honestly they should put this on the captcha

fresh comet
#

so true

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i think only an AI could read my writing

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if you fail to read my handwriting, you are 100% a human

velvet dagger
#

Acetaminophen?

solar hawk
#

16 stages of frog

fresh comet
tender tulip
#

Cochain complexes are weird

sturdy gulch
tawdry pecan
#

computer screen

ripe needle
tawdry pecan
#

🐸

tender tulip
neat lintel
tawdry pecan
#

thats my least favorite beverage

alpine valley
#

yum

burnt ledge
#

Bruh u gotta at least separate the dot and the stem of the i

hidden isle
#

whats up discussy

iron osprey
neat lintel
#

this looks a lot like mine

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i cant read my own stuff sometimes

sly flint
#

Very similar to my actual handwriting now:

fresh comet
burnt ledge
#

then bring it back afterwards

neat lintel
violet urchin
opal quail
sly flint
burnt ledge
#

you can bring back joining after you practice forming letters individually tho

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you can see rage joined their "der" in "Under"

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but each letter is still well formed because they can form them unjoined, as in "down" and "pressure"

fair mural
sly flint
#

thanks!

old nest
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Anyone know where I can find a reputable time series dataset

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like government type etc

sonic sentinel
#

how is 6 months of runway considered financially secure if a typical job search is 5 months (source: googled "typical job search length")??

solid spear
#

anyone else here prefer node to node distances instead of nodes for distances
or travelling

fervent flame
peak tide
sonic sentinel
fervent flame
#

why only have 6 months of runway then? what about 7? 8? 9? 10?...

sonic sentinel
#

ah ok

fervent flame
#

its just a general guideline

sonic sentinel
#

yeah but it sounds like a bad guideline

fervent flame
#

what would you suggest?

peak tide
#

obviously you should have as much as you can
i've known people who went a year or two looking for work

sonic sentinel
fervent flame
#

great. now when people look up "about how much runway should i have", they get told to "do your own math"

sonic sentinel
fervent flame
#

how helpful is that as a general guideline?

peak tide
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my point being, you don't stop saving just because you reach 6 months of savings

fervent flame
#

the point of general guidelines is that the are general guidelines. this applies to literally everythjng ever

peak tide
#

yea, and as you discovered, 6 months as a general guideline isn't 100% failsafe

sonic sentinel
fervent flame
#

what is your formula?

peak tide
#

but i don't think anyone ever claimed it is, 6 months is the minimum to even consider yourself not in crisis mode

sonic sentinel
sonic sentinel
#

Your 'personal runway' is how many months you can easily live if you stopped working. It's a product of the cash and sellable assets you have on hand, non-work income, your living expenses, and your ability to draw on your friends and family in times of need. For instance, if you have $10,000 of savings and live on $1,000 per month, your persona...

peak tide
river moon
#

surely you can easily count your spending and what you can/can't cut from it and roughly get an idea how risky it is or how long you can last

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nobody else knows what your spending is like

sonic sentinel
peak tide
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also on what kind of flexibility you have in your life
are you a month to month renter or do you have a huge mortgage, things like that

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if you are in a position to dial back spending to nearly zero (like move in with parents or some such) if the shit hits the fan, then you might not need a big cash cushion
if you yourself are a parent with a house and mortgage and bills to pay, you'd better have a substantial one

sonic sentinel
# fervent flame what would you suggest?

here is my attempt at something more useful:
let's suppose that there is a 50% you get a job every 7 months and this probability is independent

let current runway=x

chance of running out: 0.5^(x/7)=p

suppose the negative value of running out of money is 50 months of runway, then p(-50) would be the expected value of losing your job right now, then you could find the derivative of p(-50), call it u

the point at which u(x)=1 would be your max. runway, since anything after that would mean the expected value of putting more money into runway would be less than the actual value of that money. in our case x=16.16

#

if you give a very conservative (i think) number that the negative value of running out of money is 20 years of runway, then the x would be almost 32

queen latch
#

is their a way too look at a factorial and know what it will be without having too do all the multiplying so like know 6! is 720 without doing the 1x2x3x4x5x6?

glass peak
#

Memorise them all

rich magnet
#

I love discusion 2!

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It's so cozy and camp

sonic sentinel
#

surprisingly, my mistake wasn't catastrophic, and the values i gave still hold

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p(x) is the chance of running out of money if you have x months saved

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L is the negative utility (in months of living cost) if you run out of all money

sonic sentinel
#

u(x) is the expected value of losing your current job if you have x months of money saved

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you want to see where u'(x)=-1, meaning that the value of saving that money (for runway) is the same as not

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problems with the model:
-an average of 7 months search doesn't mean "50% chance of gaining a job in 7 months"
-the probability function might increase too slowly, since finding a job by t time and t+1 time are not independent
-discounting is not considered
-pensions or any other change in future situation is not considered
-its not exactly clear how you would get the "loss value if you run out of money" anyway. you could look at different scenarios and likelihoods (e.g. living with parents/siblings, homelessness, idk) but you would likely still have a lot of error with the likelihoods AND the estimation of how bad each thing is.

old nest
#

PLEASE help me it's been 4 hours

neat lintel
solar hawk
tawdry pecan
#

why

solar hawk
#

it told me to re install when i tried to load it up

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XD

tawdry pecan
#

understandable

solar hawk
#

i was already playing all along

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tbh some roblox games r good

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sad there are some bad ppl on soem of the others tho

tawdry pecan
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ive never tried any roblox games

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yeah

solar hawk
#

i mean like

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some of the developers know what they r doing

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some are original completely, something i cant get off of roblox

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some are just games i cant run outside of robglox opencry

tawdry pecan
#

yeah

hidden isle
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@burnt ledge I have a question regarding chemistry, do u have time?

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(Legit one)

gusty socket
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@burnt ledge i have a question regarding… chemistry…

fresh comet
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can @burnt ledge recommend me a book in organic chem

sick kite
#

@burnt ledge do you like chemistry

next schooner
#

@burnt ledge so I'm currently working on a project to do with chemistry and I hear you're somewhat of an expert

burnt ledge
hidden isle
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what the hell i didnt even check this channel and i just see all of this

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lmfaooo

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😭

burnt ledge
hidden isle
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ok i have a question

burnt ledge
#

@burnt ledge Do you know much about chemistry? I hear you're the expert

hidden isle
#

you know magnesium ribbons?

burnt ledge
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Yeag hes my buddy

hidden isle
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is it safe to run an electric current through them

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all i know is that theyre flammable

burnt ledge
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if theres any chance the current will get high, then no (because high current -> high temp -> ignite the magnesium)

hidden isle
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what about like 9 volts

burnt ledge
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add resistor maybe

hidden isle
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hm

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ok maybe ill just use aluminium foil because its safer

hidden isle
hidden isle
burnt ledge
#

yeag flammable metals are a pain

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Cant even extinguish them

short fiber
#

are you a magnesium ribbon? bc ur always so fire

onyx reef
short fiber
onyx reef
short fiber
bright hill
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trying to think of all the possible impolications this response holds holothink

short fiber
#

wh

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im not

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lying

neat lintel
#

ok trippie redd

deep mango
#

<@&268886789983436800> spam

fresh comet
fresh comet
#

I am not studying ochem

burnt ledge
#

chemical structure and reactivity by keeler and wothers is a good one for the fundamentals too

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goes into detail about organic but doesnt focus only on organic (and spends a while talking about bonding and spectroscopy

fresh comet
#

Ty!

burnt ledge
#

thats how i learnt it personally, CSR into clayden

grizzled arch
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hi everyone

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I'd love to learn from you

bright hill
#

I just meant that, what you said must imply that woman don't make women dry

#

does that mean all women are homosexual?

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guess not hmm

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maybe the opposite?

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I dunno, your response makes no sense to me KEK

acoustic yarrow
neat lintel
#

you poor poor thing

calm vessel
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:C

grizzled arch
#

same here

ocean harbor
grizzled arch
#

can you chat in English?

ocean harbor
#

ye

#

you can talk non-English in help channels though

grizzled arch
#

are you good at mathematics?

ocean harbor
#

no

grizzled arch
#

how about direct chat?

ocean harbor
#

ye

#

hi david

tame egret
#

Hi Akira

grizzled arch
#

agree with you

tame egret
ocean harbor
#

I finished it a long time ago

tame egret
tame egret
grizzled arch
#

what about JavaScript?

ocean harbor
#

i use bing ai for that

tame egret
ocean harbor
#

so pretty much not good at it lol

ocean harbor
#

I use js, react, html and css for creating a website or smth

tame egret
#

I saw an 'if dora had african parents vid'

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it was brutal

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Good bye Akira!

ocean harbor
#

bai

#

studying for da canadian citizenship test 🙏

neat lintel
#

good luck

tame egret
#

Minato don't randomly send messages to people!

neat lintel
#

Hello people

mystic ivy
#

hi myanus

burnt ledge
#

‘good’ rather than 'good'

fresh comet
neat lintel
#

okay so

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i'll ask you to take some (hopefully believable) things on faith there

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mainly about how sequences and convergence work in R^2

fresh comet
#

I usually have to convince myself of stuff after the fact

neat lintel
#

that's how i've been doing it since i was in 157/247 catgiggle

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alright so

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let's say we have a continuous function f: R -> R

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we are interested in saying something about the graph of f

fresh comet
#

okay..

neat lintel
#

sorry hold on i'm also sorting out some work stuff at the same time

fresh comet
#

no worries

neat lintel
#

my job training got approved, i can start making money now

fresh comet
#

do your job first lmao

neat lintel
#

it's the weekend so it's not really doing my job lol. just sorting a few personal things out (payment accounts n tax shit)

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US people have crazy ass tax forms

fresh comet
#

tax forms seem very annoying

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I had to print out my first forms 2 weeks ago

neat lintel
#

i need to sign a form that basically tells the IRS not to tax me because i'm not a US citizen

#

okay so, what do we know about f? if x_n -> x, then f(x_n) -> f(x). so this implies (and this is where you'll have to start believing) that (x_n, f(x_n)) converges to (x, f(x))

fresh comet
#

okay

neat lintel
#

this (x_n, f(x_n)) is a sequence contained in the graph of f

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what the condition "x_n -> x, then f(x_n) -> f(x)" is saying is that, if a sequence in the graph of f converges, then it must converge to something in the graph of f

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if (x_n, f(x_n)) converges to something in R^2, say, (x, y), then (believe me!) x_n -> x and f(x_n) -> y. by continuity we know that f(x_n) -> f(x) as well, so (x, y) = (x, f(x))

fresh comet
#

hmm

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I don't really have a good mental picture of what's going on lol

neat lintel
#

picture the graph of f and a convergent sequence inside of it

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(do you have a good idea of what a convergent sequence in R^2 would look like?)

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(the points get closer and closer to something)

neat lintel
#

cool

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we won't worry about the definition; definitions are for mathematicians and we're physicists

fresh comet
neat lintel
#

by what i said above, the continuity condition on f is implying that a convergent sequence contained in the graph of f must actually converge to something in the graph of f

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the limit of the sequence cannot lie outside the graph; it must be inside

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let me illustrate with a non-example, actually

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let's say f is zero everywhere, except for 0 where it equals 1

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in the graph of f, let's consider the sequence (1/n, f(1/n)) = (1/n, 0)

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what does this converge to?

fresh comet
#

uhh

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I would think that it approaches 0?

neat lintel
#

1/n does, but what about the tuple (1/n, 0)?

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(don't overthink it)

fresh comet
#

okay let me clear something up

neat lintel
#

sure

fresh comet
#

how am I supposed to think about this graph

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is it in 3D?

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or something else

neat lintel
#

it's sitting inside R^2

fresh comet
#

so on a sheet of paper

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?

neat lintel
#

sure

fresh comet
#

(0,0)?

neat lintel
#

yup

#

is (0, 0) in the graph of our function f?

fresh comet
#

no

neat lintel
#

indeed

fresh comet
#

?

neat lintel
#

f is discontinuous, and (0, 0) isn't in the graph of f

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so despite this convergent sequence being in the graph of f, its limit ended up outside because f was discontinuous

fresh comet
#

right

neat lintel
#

(maybe i should say it the other way around, that f is discontinuous because this limit is outside the graph, since i've only been talking about the "f continuous implies graph sequence etc." direction)

fresh comet
#

(is a contour the best way to think about graphs in R^2??)

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that's the mental image I'm using

neat lintel
#

as long as the contour is actually the graph of a function (vertical line test), sure

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so this property - that a convergent sequence sitting inside the set actually converges to something in the set - is called "closedness"

fresh comet
#

hm, okay

neat lintel
#

so we've established (up to taking how sequences work in R^2 on faith) that, if f: R -> R is continuous, then the graph of f (a subset of R^2) is "closed"

fresh comet
#

right

neat lintel
#

as for the other direction...

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this is where things get quite unfortunate

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let's try to follow our noses and see what we can come up with

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we assume that the graph is closed, a condition on convergent sequences contained in it. we want to take a convergent sequence x_n -> x in R and show that f(x_n) -> f(x)

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well, we know something about sequences in the graph, so the natural thing to consider is (x_n, f(x_n))

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but we can't apply the graph closed hypothesis!!!!! this might not converge!!!!!!!!

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woe is us

fresh comet
#

eeveethink so then what?

neat lintel
#

we cry

#

our classification broke

#

we need to impose an extra condition on the codomain of f for this to hold

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have you learned about the bolzano-weierstrass theorem yet?

fresh comet
neat lintel
#

cool

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i wish we had learned it that early openbleak

#

god, i just fucking LOVE dedekind cuts!

fresh comet
#

we did dedekind cuts in our first month too

neat lintel
#

i'm still mad about 157

fresh comet
#

(I died)

neat lintel
#

what i will assume about the codomain of f is that every sequence inside of it has a convergent subsequence

#

a condition which should look familiar

#

so now we're considering some weird thing like f: R -> (some subset of R with the above property like [0, 1] or [-21342131313, 100])

#

the meaning of continuity doesn't really change

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but i figure it's good to point out

fresh comet
#

I see

neat lintel
#

is today a holiday? i think i can hear fireworks downtown

fresh comet
#

I don't live downtown

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I don't even live in Toronto lmao

neat lintel
#

i'm like riiiight in the middle

woven cape
#

hi i'm new

neat lintel
#

ok let's not let me distract us

#

so x_n converges to x, cool. now we know that some subsequence of f(x_n) converges

#

let's say that that subsequence is f(x_{n_k}), and that it converges to y

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x_{n_k} still converges to x

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sounds good so far?

fresh comet
#

good so far.

neat lintel
#

so now we can get a convergent sequence in the graph!

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(x_{n_k}, f(x_{n_k}))

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wow that looks awful in plain text

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$x_{n_k} \to x$ and $f(x_{n_k}) \to y$, so $$(x_{n_k}, f(x_{n_k})) \to (x, y)$$

fathom swallowBOT
#

ТТерра

neat lintel
#

it's time for our assumption about the graph of f to shine

#

we have this sequence in the graph of f which converges to (x, y), so, by our assumption, (x, y) is in the graph!

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what we have ultimately shown is that, if x_n -> x, then f(x_n) -> y = f(x). f is continuous!

fresh comet
#

hmm

#

this is something I'd do in 257?

neat lintel
#

yeah

#

the first bit of 257 should talk about topology in R^n

fresh comet
#

even more reason to study top over the summer lol

fresh comet
#

why is that

neat lintel
#

to recap all this math discussion,

  1. if f is continuous, then its graph is "closed"
  2. if the graph is "closed" and sequences in the codomain of f have convergent subsequences, then f is continuous
    so "graph is 'closed'" is almost a characterization of continuous functions
neat lintel
fresh comet
#

I can't think of a major counterexample in LA now that I think about it eeveethink

neat lintel
#

i'm surprised someone hasn't come in and told me that i need to assume f maps to a Hausdorff space. what's happened to this fucking server...

fresh comet
#

but I can think of maybe half a dozen in 157 analysis

fresh comet
#

what is a Hausdorff space though

neat lintel
#

distinct points can be separated by disjoint open neighbourhoods

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it's what lets you say that limits of sequences are unique, for example

neat lintel
#

hausdorffness implies that y and f(x) are equal, but in some turbo shit space no one really cares about we may not have been able to say this

jagged forge
#

i still remember learning what convergence in the cofinite topology is like and being like "wait, wtf"

neat lintel
#

(inb4 nets)

fresh comet
#

lmao

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or whatever other stupid situation nobody talks about

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or cares about, rather

fresh comet
neat lintel
#

i woooooouuuld like to comment: functional analysis has a result called the "closed graph theorem" which says that a linear map between two nice whatever spaces (e.g. hilbert spaces, which i was telling you about when we discussed riesz's theorem) is continuous if and only its graph is closed

#

so over there life is good

neat lintel
#

i dunno if linear algebra really has any "key counterexamples"

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it's just too nice

fresh comet
#

I like thinking about LA more than RA for that reason

#

it makes more sense to me

neat lintel
#

the first one that comes to mind is that an infinite-dimensional vector space is no longer isomorphic to its dual. this is disastrous

#

terrible!

fresh comet
#

what do we lose for it

neat lintel
#

nothing because the only time anyone cares about an infinite-dimensional vector space is when it's a hilbert space and there we only care about continuous functionals

#

(the "the only time anyone cares..." part is a lie, but pretend it's true so i can have answered your question)

fresh comet
#

fair enough lol

neat lintel
#

maybe a "main counterexample" would be like

0 1
is not diagonalizable```
#

idk

fresh comet
neat lintel
#

so true

tender tulip
#

This looks AI generated

fair mural
tender tulip
#

Bender and the drink machine

fair mural
#

ok wait that’s totally a bear in the bottom right

tender tulip
#

Dog

fair mural
#

aren’t they both canines hmmcat

glacial panther
#

I just learnt that latex actually takes time to learn

#

I thought it'd be like desmos where I just need to type stuff in

#

so dissapointed

neat lintel
visual breach
#

Tho it is worthy to point out that LA stuff is generally behaving well

sly flint
neat lintel
sonic sentinel
# fair mural

i see a takeout carton, some jewellery, plastic bags, a red lid, and some ai artifacts

worthy orbit
#

just quickly;
My Coursework asked to plot a "theta versus t , and and x versus y" X and Y are parametric. But it feels unconvential to plot X on the y-axis am i being tricked

#

confused if versus is as significant a statement as against

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or if im just meant to use common sense :|

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bonkers stuff

knotty spoke
#

Also the patterns on computers and stuff are flawless

#

if it was ai generated, it wouldn’t be like that

tender tulip
#

It’s funny because it looks AI generated at first but it isn’t

quartz crypt
#

what is heat?

#

like when heat radiates into vacuum

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what is actually lost

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(this should be the smartest discord server im in)

mystic flower
quartz crypt
#

whats magnetic force, like when those double donut things radiate out of a magnet bar, whats actually travelling

sonic sentinel
#

alshfik's tips for success:

  1. put zero effort, and expect the best
  2. never apologize; it shows weakness
  3. ruminate on lost time
  4. optimistic plan + optimistic deadline = realistic action + realistic deadline
  5. ruminate on lost time
quartz crypt
#

woah. i watch discord say you were typing for a long time, anticipating an answer. but this

#

i wonder if the moon is cooler when earth has rampant greenhouse effect

sonic sentinel
#

its not even that funny in its current form

naive hull
#

including length contranction and pseudo forces yk

quartz crypt
#

so ICP was right

naive hull
quartz crypt
#

pseudo is just science lingo for magic

naive hull
naive hull
quartz crypt
#

its warps reality of magnetic materials

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oh

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its for kids too

naive hull
#

"energy always spreads out"

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or maybe something like ||entropy||

quartz crypt
#

well anyway, its called "electromagnetic energy" and is possibly the "excitation in a quantum field"
but i reached the limit of my curiosity

knotty spoke
unborn trellis
#

When a charge distribution moves, you get current which by Ampere's law produces a new magnetic field. You can think of this being necessary because without the induced magnetic field, the electromagnetic energy contained in your configuration depends on which reference frame you're viewing the physics from

#

If you don't have an induced magnetic field, then moving from a frame in which a charge is still (the rest frame of the charge) to a frame where it's moving (some other frame where it looks like current), then the energy contained in the current is not the same as just the charge

naive hull
unborn trellis
#

Iron exhibits ferromagnetism, where the magnetic field is static

#

It arises from spin coupling of electrons inside the material

unborn trellis
#

So there is tiny currents going up and down constantly randomly inside

unborn trellis
naive hull
unborn trellis
#

Maybe

#

This is more solid state physics

naive hull
#

yeah cos ferromagnetism arises from there ih

proud olive
#

Fear that I'm supposed to know this

naive hull
#

the latest one

#

(chemistry)

proud olive
#

Type of bonds?

#

Pi bonds and stuff?

naive hull
#

there are like 5 theories on chemical bonding

proud olive
#

Is the other one called the sigma Bond?

naive hull
#

3*

unborn trellis
#

this one has quantum mechanics..... cojerry1

naive hull
proud olive
#

Aight ty

#

That's probably the thing I'm supposed to know

naive hull
naive hull
proud olive
#

Math

#

And physics ig

naive hull
#

oh-

naive hull
sly flint
naive hull
unborn trellis
#

Physics of solids yeah

proud olive
#

It was taught in a general chemistry course. Wasn't much more advanced than that

naive hull
#

elasticity and stress

sly flint
#

ah, of course

naive hull
#

more than that ofc

unborn trellis
#

Those aren't usually what they care about in solid state

naive hull
#

thats some basic stuff ik about

unborn trellis
#

It's usually thermal and electrical properties

proud olive
#

Historese diagram and stuff

unborn trellis
#

Those are linked to the physics of the material itself pretty deeply

sly flint
#

So the study of say super conductors comes under solid state physics?

proud olive
#

Extremely boring stuff by other words

unborn trellis
#

Definitely

proud olive
#

Impressive that very able to make progress in a field so unbelievably boring holy shid

naive hull
unborn trellis
alpine comet
proud olive
naive hull
unborn trellis
#

You can literally get formulas for the statistical behavior of gasses by approximating the number of lattice points in a sphere using stat mech

#

There's a lot of cool emergent physical properties that come from somewhat simple math

naive hull
naive hull
unborn trellis
#

Lol

fresh comet
#

I see we're on the topic of physics

unborn trellis
#

Strings

naive hull
alpine comet
naive hull
#

tension and stuff?

fresh comet
#

there's something I need to get cleared up lmao

naive hull
#

NLM?

alpine comet
#

but afaik, that has gone to nowhere

fresh comet
#

how do charges feel the electric force

unborn trellis
#

It's like if you did quantum field theory but your lagrangian for relativity uses surface area of "world sheets" instead of lines through spacetime

sly flint
fresh comet
naive hull
fresh comet
#

eeveethink I feel like there should be a better answer

unborn trellis
#

how do they feel it...

alpine comet
unborn trellis
#

Photons get pinged back and forth

fresh comet
alpine comet
#

I feel cursed already just by knowing what they mean

naive hull
unborn trellis
#

In fact, if you do relativistic E&M, you'll see that there's something called a domain of influence around a charge

unborn trellis
#

Basically, depending on how a charge is moving, there is a region around it corresponding to how far photons can move in a specific small chunk of delay time

#

It's called "retarded time" electromagnetism

fresh comet
#

are these photons observable

unborn trellis
#

Probably

fresh comet
alpine comet
unborn trellis
#

But yeah, time retarded electric fields suggest that photons have to propagate at speed c to influence a charge

fresh comet
#

then what happens if I create a new charge out of thin air

unborn trellis
#

You would violate conservation of charge

fresh comet
#

do photons immediately start getting sent everywhere in space

unborn trellis
fresh comet
#

lmao

unborn trellis
#

This is what radiation is

unborn trellis
naive hull
sly flint
#

How do these charges produce said photons out of seemingly nothing?

naive hull
unborn trellis
#

uh so basically if you spawn two opposite charges, this violates physics when you do the math yes

#

And this is suggestive of a specific flaw, which is that point charges as delta functions are unphysical

alpine comet
naive hull
#

didnt notice that

fresh comet
alpine comet
#

but if one of the particle is antimatter

#

then nothing stops you from doing just that. In fact, it happens all the time. That's how Hawking radiation works

unborn trellis
#

Pair production doesn't come from nowhere lol

fresh comet
unborn trellis
#

Photons have to decay into the electrons

fresh comet
#

but it doesn't come from charges

naive hull
unborn trellis
#

Yes, you go from 0 net charge to 0 net charge

unborn trellis
#

It's the fundamental interaction

fresh comet
naive hull
fresh comet
#

and then photons start getting sent to everyone?

sly flint
#

I have motivation to study physics now sotrue

unborn trellis
fresh comet
#

but these new electrons/positrons need to start telling everyone they exist

#

right?

unborn trellis
#

Im saying a charge configuration of two electrons of equal and opposite charge getting sent toward each other as "equivalent to no charge at all" is unphysical

#

You're talking about a photon decaying into two electrons which will scatter in literally opposite directions

fresh comet
#

mhm

#

but that wasn't the point I was trying to make

#

I was asking about how that newly formed electron/positron pair starts sending photons everywhere

#

what causes that to just start happening

unborn trellis
#

It's just the particles spitting out energy essentially

fresh comet
#

how do they not lose energy then?

unborn trellis
#

They do, which is why high energy particles fizzle out of existence

proud olive
#

Which is why the electron is spiraling down into the nucleus

#

Currently

unborn trellis
#

They decay immediately into lower energy things

unborn trellis
#

In fact this is why they developed quantum mechanics

fresh comet
unborn trellis
#

They do! But they can exist longer because they're more stable

proud olive
#

Don't tell me that electrons act like clouds around the nucleus that's just nonsense

fresh comet
#

hmm

proud olive
#

(I was too slow)

fresh comet
jagged forge
#

is this virtual particles

fresh comet
#

idk?

#

I can't tell if these photons are real or not

unborn trellis
fresh comet
#

I see

#

is that rate supposed to be high?

unborn trellis
fresh comet
#

why doesn't everything look insanely bright then

unborn trellis
#

It can be high

#

It's called blackbody radiation

fresh comet
#

I see

unborn trellis
#

Most things do not have high "emissivity"

#

Glad to know studying physics has been useful for something lol

proud olive
#

Except for my car brakes

fresh comet
#

as in, what field of physics do you study

unborn trellis
#

I'm an undergrad in math and physics

#

Next year I'll be starting my PhD in math but I'll be studying mathematical physics

#

I do all sorts of stuff

#

QM is my niche I guess

jagged forge
unborn trellis
#

I see, my point is that with virtual particles it's just a different physical scenario

jagged forge
#

ah

fresh comet
#

good luck with your studies

proud olive
#

But sometimes that doesn't always work either so then we use a special tool called "renormalization" so that everything works out even when the math doesn't

#

Anyway, shoutout to Fubini for inventing Feynman's trick

dire glen
proud olive
#

Weird that they lump it together with LU and qr decomp since these topics feel much more vast in comparison

#

It's a good and highly relevant course if you're not familiar with this stuff from before

#

If you don't take a whole lot of math courses then yeah, that could very much be the most important math course you'll ever take

tame egret
burnt ledge
#

no prob 😁👍

dire glen
#

@proud olive thanks for the encouragement

#

from what i see it's basically the book and some videos.

proud olive
dire glen
#

i'm worreid that it might be too complex and i get stuck somewhere

proud olive
#

Seen him many times before for when I needed to learn about these stuff

#

It does indeed seem like the curriculum is pretty massive for a course like that

#

You'd be right in being worried, but man I wish I could take a course from MIT tho

dire glen
#

if you see this course for example, is structured differently. I mean it's all on the website

#

i guess if i get the book it would be the same... but i need to figure out when to look for the videos

proud olive
#

Yeah maybe but it's just not the same as actually being there seeing those professors irl that constantly appear in your yt feed

dire glen
#

yea but i can't be there so i'm trying the best option haha

proud olive
#

Not completely sure what I should compare between these two courses in terms of structure

#

They seem pretty similar to me

#

But if you haven't had single variable calculus then you should start with that

#

I'd imagine it's an easier course

dire glen
#

i mean how the course is presented. in the latter you have the menu on the left with all chapters and subchapters. and in each page you have clips, pdf lectures, exercises, recitations....

#

the previous link it's not like that

#

it's like,get the book, here are the recordings, here the exercises

#

up to you figure out what to do when

#

good luck

proud olive
#

These styles highly depend on the professors lecturing them and how long the course has existed and how many students that are taking the course

#

I'd imagine more student take the latter course you mentioned which also leads to the professor getting more feedback on the site and other resources

#

While this is a course fewer but more experienced students would take who might not require as much assistance as the more freshman like student would need

#

As I see it, it is a course for the more mature engineering student

dire glen
#

gotcha

proud olive
#

A 2 year student maybe

random rover
#

is there anyone alive here

tame egret
remote oxide
#

yes

tame egret
#

no

remote oxide
#

yes

tame egret
random rover
#

OK guys eat well and sleep well OK

tame egret
random rover
# tame egret no

dare to say that again and u well be eaten by a hellokitty monster

lilac folio
#

1 grillion dollars to the first person to give me 100 dollars

remote oxide
clear fox
#

What are the differences between differential, point set, and algebraic topology?

deep mango
#

Differential topology studies smooth manifolds, which are a certain kind of topological space. And it studies smooth functions between them

#

Topics in differential topology include embeddings, intersection theory, and differential forms

#

And like genus n surfaces and stuff

#

Algebraic topology studies how abstract algebra can be used to understand topological spaces, mainly via homotopy (the fundamental group) and homology (the homology groups).

lapis jungle
#

wtf are these nerd reactions

stray epoch
#

how would I calculate a 45% chance of something happening and that thing happening 7 times in a row

magic meteor
#

isn't that (45%)^7

deep mango
ocean harbor
compact magnet
#

I was in discussion with someone in help but I think they went off, anyone got a spare minute to answer a quick question?

#

It’s about simple trigonometry

#

I don’t need solutions I already have the answer, I just want to ask if my working out method is viable is all

#

Just to clarify if I have 1.1 = 15/x, I can either divide by 15 on both sides to get x on its own, or I can multiply both sides by x which gives me 1.1x = 15 then divide by 1.1 on both sides to get x on its own, I’m just wanting to make sure that 1.1x divided by 1.1 is x that’s all

wild lantern
#

Also, yes if you have 1.1x=15 you can divide both sides by 1.1 to isolate the x.

compact magnet
#

Ty

jade ocean
dire glen
#

a parametrization of a line is a way of listing all the points on the line.
how is this different from an equation of a line?

#

in y(x), can't i interpret x as a parameter?

#

maybe the parametrization is an "explicit" form of setting the coordinates?

river moon
#

they are two ways to represent the same thing

plain owl
#

"equation of a line" sounds like an unconventional name for parametrization

dire glen
#

but like

#

y = 2x +5

#

is the one is normally teached right?

#

it's an equation

#

it starts at the right time

river moon
#

there are many ways to describe a line which are taught in the university

#

the set of points of the form (t, 2t+5) for all real t is the same line as the one described by y = 2x+5

ocean harbor
#

<@&268886789983436800>

leaden torrent
#

@neat lintel dont post unsolicited ads

neat lintel
#

2

neat lintel
alpine comet
#

!da2a

quasi jettyBOT
#

No need to ask “Can I ask…?” or “Does anyone know about…?”—it’s faster for everyone if you just ask your question! See https://dontasktoask.com/

prime lily
#

is there any fast algorithm to compute square of a 4x4 matrix by hand? Or the definition is the only way

neat lintel
alpine comet
#

he said fast

fresh comet
alpine comet
sudden surge
#

Is there a graphing calculator that can handle multiple functions besides Desmos?

sudden surge
# sly flint geogebra

Okay. Great. I think I was having trouble using Desmos to graph equations with multiple functions.

neat lintel
#

@shrewd loom lets talk here

sly flint
#

im gonna join in

neat lintel
#

i code python a lot

fresh comet
#

discussy exploding today fr

neat lintel
#

on my school chromebook

fresh comet
#

wth

sly flint
#

literal madness

neat lintel
sly flint
#

and nami with his semantic arguments like the fuck dude

neat lintel
#

use vscode.dev

sly flint
#

welcome to the gang

neat lintel
#

for running code i have a program called WRECKED (working runtime environment creation kit enabling debugging) which is written in js

#

which graphics library are u using

#

i personally use html and the dom bc school chromebook

#

ah

#

oh ok

#

oh ok

#

yeah i’m very advanced

#

today i coded a program to simplify arbitrary boolean functions

#

for my redstone computer

#

good thing amukh isnt here rn he would be so angry at me

sly flint
#

I'm planning to make an outfit chooser thing based on colour theory and AI, lets see how that goes

neat lintel
# sly flint oh how does it work

modified quine mcchusley that i figured out myself, basically finds canonical sop, merges terms iteratively through absorbtion and AB’ + AB = A, and then brute forces set cover problem/various polynomial time approximations i invented/normal O(n) algorithm

sly flint
#

since I only got like 4 pants and 12 tshirts opencry

neat lintel
#

solves a 5x7 truth table in a negligable amount of time

neat lintel
#

brb guys be back in 10ish mins

#

go look at the wiki page for “karnaugh maps” and outlinks to understand lingo

sly flint
#

oh we were actually supposed to have kmaps this year in AI but they deleted it for some reason

neat lintel
#

yeah

#

fun fact i have no formal cs education

#

anyway be back soon

sly flint
#

I've took it as an HS elective but it doesn't go too deep monkey

#

duck, what field do you want to go into?

fresh comet
#

TCS!

sly flint
#

Yes, 100%

fresh comet
#

theoretical computer science

sly flint
#

pre prepared for copious math though devilish v

#

fr fr

fresh comet
#

waste of effort, you should figure out how to make fusion power efficient instead

#

then maybe the colleges will accept you

sly flint
#

But don't forget to establish world peace first, college likes diversity

fresh comet
#

you need to cure cancer before even being considered for a nobel

sly flint
#

^^

neat lintel
#

back who wants to talk about cs

ocean harbor
#

lets talk about how cringe java is

neat lintel
#

sure

ocean harbor
#

lmao what

neat lintel
#

SO MANY WORDS AND SO SLOW

ocean harbor
#

I saw what you deleted

#

no you

#

but duck

neat lintel
#

oh that

sly flint
#

discussy is political again

neat lintel
#

ye

sly flint
#

speed what's a hash map

fathom swallowBOT
#

Gave you the studying! selfrole.

ocean harbor
neat lintel
ocean harbor
#

smh you leave when im here

sly flint
neat lintel
#

wikipedia, other websites

#

experience

sly flint
#

wikipedia 💀
I think it's more of a reference than anything

#

yes but how did you get that experience

neat lintel
#

used linux, first touched windows at 8, started scratch at 7 and python at 8

sly flint
#

ah, i see

neat lintel
#

dad’s good at coding

#

also i do schoolwork fast (100 wpm + bad handwriting = teachers let you type assignments also smart)

#

so can code at school

sly flint
#

can't even bring phones

neat lintel
#

we got chromebooks

#

4 gb ram

sly flint
#

we got uhh- paper and pens

neat lintel
#

oh ok

#

tho coding python on a school chromebook without knowing anything about js/html is hard

#

ofc now i know js/html

sly flint
neat lintel
#

yeah i always push the limits

#

my 3rd question to gpt4 broke it

#

also i like running large brute-force np-hard problems

sly flint
#

I pushed the limits too hard and my laptop started melting so 💀

neat lintel
#

lol

#

anyway time for daily minecraft session

#

also one time i accidentally had my computer running for 5 hours computing steiner systems

sly flint
#

what for?

neat lintel
#

hamming distance

#

oh no amukhs on hopefully he dosent see this

sly flint
#

lul

solar hawk
neat lintel
#

last time i talked about coding u said u were gonna block me

solar hawk
#

Yeah

#

Cuz u were being a freaking crank

tawdry pecan
#

lmao

neat lintel
#

scroll up

solar hawk
tawdry pecan
#

Are steiner systems related to topology at all? They give off that vibe

solar hawk
#

Topology is good

tawdry pecan
#

I dont know too much about topology, but what i do know is fun

solar hawk
#

So good

neat lintel
tawdry pecan
#

yeah but something about the way that its groups of digits that share a certain number seems like topology on sets

sly flint
#

under what field of study do steiner systems come?

neat lintel
#

idk

tawdry pecan
#

uhhh error correction

#

idk the math field

neat lintel
#

lottery gaming

tawdry pecan
#

true

neat lintel
#

how i learned about them

#

and then i realized why my hamming distance calculations took so long

tawdry pecan
#

i wathced that one video on them

#

ill try to find it

solar hawk
#

What happened you your state of the art adder design speedy

tawdry pecan
#

⬣ LINKS ⬣
⬡ PATREON: https://www.patreon.com/anotherroof
⬡ CHANNEL: https://www.youtube.com/c/AnotherRoof
⬡ TWITCH: https://www.twitch.tv/anotherroof
⬡ WEBSITE: https://anotherroof.top
⬡ SUBREDDIT: https://www.reddit.com/r/anotherroof

⬣ ABOUT ⬣
I have loved this diagram ever since I first saw it on the coffee cup of one of my lecturers / collea...

▶ Play video
#

this one

sly flint
#

hmm, tbh, i've lost motivation to study further cs

solar hawk
#

:(

tawdry pecan
#

lol

solar hawk
#

What the fuck have you done speedy

neat lintel
#

kmaps were mentioned earlier

solar hawk
#

This is WHY CS CRANKS ARENT ALLOWED

tawdry pecan
#

what are you gonna study next?

neat lintel
#

was working on it all day

#

im not a crank

sly flint
tawdry pecan
#

ah nice

#

i am really bad at physics, i have 0 intuition lmfao

neat lintel
#

also its not state of the art design

#

its for 4-bit redstone computers in minecraft

solar hawk
#

design

neat lintel
#

wait whats ore

solar hawk
#

Bruh

#

I’m blocking you

neat lintel
#

no actually

#

tell me

#

oh wait

sly flint
neat lintel
#

forgot about google

solar hawk
#

Open redstone winger it’s

#

Einteiler

#

ENGINEERS

#

FUCK

#

ok

neat lintel
#

oh those guys

#

not part of that

solar hawk
#

Why

#

Ore is good

tawdry pecan
neat lintel
#

i will when i finish my 4 bit computer

solar hawk
#

Go on ORE?

neat lintel
#

ig

tawdry pecan
#

ive tried to program a double pendulum a couple times, and it just ends with me randomly changing values praying it works lmao

neat lintel
#

oh gl

tawdry pecan
#

too much trig

#

and too many ways to simulate physics too lmao

sly flint
tawdry pecan
#

I mean yeah i could, but then you dont learn as much

sly flint
#

You don't need to start from scratch every time, there are tools and you use them to accomplish what you want to simulate
but if you want to practice, it's good practice, however doing both at the same time is just a waste of time

tawdry pecan
#

yeah

neat lintel
#

one of my rules is ALWAYS start from scratch

tawdry pecan
#

its mostly for fun anyways, but if I ever become super desparate ill use a library(god forbid)

sly flint
neat lintel
#

and then when u figure out you cant/it'll take too long give up and use a library

sly flint
#

oh opencry

neat lintel
#

(generally happens within an hour for me)

tawdry pecan
#

i think out of everything ive made, ive only used a library once or twice, i just like the feeling of doing it all, ik im screwing myself over tho

sly flint
#

another thing with physics is that there's an abscence of clarity in what your next steps should be, I find math to be just more "well organised"

tawdry pecan
#

most the stuff i make is pretty short anyways

neat lintel
#

i use libraries like pyodide, numpy (sometimes), graphics libraries

#

and ai libraries

tawdry pecan
#

i use javascript so i dont use them lmfao

sly flint
tawdry pecan
#

obviously when im doing a school project or smth i use libraries (and a better language)

neat lintel
#

i use keras lol

#

im not doing all that matrix algebra

sly flint
#

it's a part of tensorflow irealshit

neat lintel
#

also tutorial in book i think its called "ai with python" or one of those generic names

#

show pic of cover

#

and i will verify

sly flint
neat lintel
#

kw later i can show pic of the cover of the book i used to learn keras

sly flint
#

ah

neat lintel
#

discussy's somehow still political

#

nvm

solar hawk
solar hawk
neat lintel
solar hawk
#

lol

neat lintel
#

the one and only way i am not a crank

solar hawk
#

😭

neat lintel
#

at least according to u

#

imo i am not a crank i am just a self-taught coder

fresh comet
#

@solar hawk from FIS

solar hawk
#

abs alg?

#

ngl idk what these words iz

fresh comet
#

my LA textbook

solar hawk
#

what chapter is this

fresh comet
#

6.8

solar hawk
#

i mean the topic

fresh comet
#

pg 430

solar hawk
#

did do fish iso yet

fresh comet
solar hawk
#

ye

fresh comet
#

"Inner product spaces"

solar hawk
#

ohh

#

thanks

fresh comet
#

I don't think we're gonna cover FIT

solar hawk
#

why?

fresh comet
#

I'll probably look into it in my own time

solar hawk
#

its my favroite

fresh comet
#

back when we did R-N last semester, we shoulda done it lmao

#

but we didn't so

#

here we are

solar hawk
#

you would do it when you do quotients

fresh comet
#

we aren't really touching quotient spaces afaik

solar hawk
#

:(

fresh comet
#

I could be wrong

tender tulip
#

Amukh knows group quotients? Real

fresh comet
#

we have some extra topics at the end of the course

#

maybe then

solar hawk
tender tulip
solar hawk
#

they r just as good

#

no worry bt normal subgroup

unreal basin
#

Hi, Is anyone aware of any tools that would integrate free hand drawing on a tablet with something like wolfram alpha? Optimally I'd like to free-hand write an equation and if i need help send that off to wolfram alpha? I tried searching online, there seems to be microsoft math assistant or one note, but doesn't seem to allow for advanced stuff

neat lintel
#

did u remove 2 or what happened i got a notif

main void
#

Paraboloid

unreal basin
sudden surge
#

Is this true:

Difference between Δ, 𝑑, 𝛿 and ∂
Δ - finite variation of a quantity (not infinitesimal)
𝑑 - infinitesimal variation of a quantity or differential operator
𝛿 - infinitesimal variation of a quantity or variation of a functional

solid snow
#

infinitesimal

neat lintel
#

I've probably said this a million times but it's really humbling knowing that math goes so much deeper than calculus. As a sophomore I thought I was a genius, and when I stumble upon other parts of math I feel increasingly ignorant.

visual breach
neat lintel
visual breach
#

Well, it seems so when e.g. peers are going much ahead, and I seem to achieve nothing

#

Some part of it is my laziness, but still..

neat lintel
#

it might just be different pathways in learning.

#

what are you studying?

visual breach
#

I am searching around various subjects rn

#

Taking algebraic geometry, differential topology and basic arithmetic number theory classes.

neat lintel
#

are you having success in those classes?

visual breach
#

I don’t know, the grades are generally generous and I am understanding some

#

But I am not able to go beyond just understanding, it seems.

#

It’s even worse when some parts just seem like definition bashing

neat lintel
#

would you mind explaining what you mean by "beyond"? Like are you talking about mathematic intuition?

visual breach
#

Yep, intuitions and stuffs like

#

I am supposed to understand what people are saying when they state some mathematical stuff

neat lintel
#

Granted, it would be hard for me to understand given that I'm not in your boat. I think that when you are looking at math(or any topic) from an extensively broad standpoint, the nuances of certain problems can result in challenges in understanding and applying a practice. Error and fatigue is inevitable, but time helps to alleviate those problems.