12:02 PM
annndddddddd i have another question
so the force on a current carrying wire while its under influence by a magnetic field is directly proportional to the length of the wire?
that doesnt seem right for some reason

The longer the wire, the more stuff exposed to magnetic field

@0celo7 I am very happy you got it; I'm not sure about what exactly it was about anymore, but surjectivity should definitely be the case if we take the - now I'm actually missing the right mathematical terms in english, sorry :( - well, let's say if we take the $^C$ in the domain and then invert - otherwise it does not really make sense, does it?
anyway, sorry, my math classes were one of the few things where I stuck to german literature, so I'm a bit lost for words
but I'm happy you solved it :)

@Sanya The ${}^C$ is the complement in English, too

@ACuriousMind I didn't want to mention that I'd forgotten the german name too

Haha, okay :D

12:06 PM
my last analysis class was in 2012 I think
or 2011

oh ok

afterwards I only did algebra as a minor in the master degree course but well ... no functions there

Help
I am cold
Someone expand the sun

just polute more

engulf the earth in flames

user116211
12:11 PM
Drink hot coffee.

Sorry I'm an energy drink man

^me
on the right

user116211
Cut down some tree logs; make a fire.

when do they teach you cross products?
like, vector cross products
i have no idea how to take them
sal khan on khan acadmey is treating the length of a wire as a vector quantity and taking the direction of the length

12:18 PM
when do they teach cross products? depends on your country
and the subjects you study
but usually in your first physics course
it's basically just multiplying the components that are at right angles to one another

Cross product was like early university here, I think
Like first year I think

i am 10th grade so maybe i should just ignore em lol

he is using the right hand rule anyway so i understand
ambition?
well...i like physics

ambition = how successful you want to be
an example of cross products is the area of a square

12:21 PM
i wanna be like elon musk
ye

you take one length and mulitply it by the other length that is perpendicular to it

i think its related to directions too..

yes you only multiply together the perpendicular components

like, multiplying 2 or more things involving vectors and then figuring out if the product is a vector or not and if it IS a vector then figuring out the direction

yes
the right hand rule
there are several different "right hand rules" that all acheive teh same result
I believe sal kahn goes through one in the video

12:23 PM
yea

e.g. suppose i want to compute X cross Y

fleming's right hand rule

and X is a vector pointing to the right
and Y is a vector pointing up
then X cross Y will be a vector pointing out of the screen

90 degree between em

and Y cross X will be a vector pointing into the screen

12:24 PM
oh
oo dats complicated
but cool
k thanks again!

np

to everyone
lol

1:19 PM
I need some help here..... I was almost driven crazy...
I am working on a problem: design an RC low-pass filter that has $V_{out}/V_{in}=0.5$ at 5kHz
my answer is: $RC = 3.46\cdot 10^{-4}$
but the answer said 5.5 x 10 ^(-5)
it is a straight forward calculation, I don't know where is wrong...

@Shing Since you haven't told us anything about how you computed that number, we can't tell where you are wrong (or not) either

@ACuriousMind I simply used the equation $V_{out}/V_{in}=\frac{1}{(1+\omega ^2 R^2 C^2)^{1/2}}$
um... wait I think I made a stupid mistake
the omega is angular freq....
damn

1:40 PM
I was about to remark that the ratio between your two results was suspiciously close to $2\pi$ ;)

lol thanks, man.

so I'm working on Euler problem 8
and I really have no idea how to even start solving it.
it isn't a matter of writing the code, its a matter of figuring out how to do it.
my initial idea was to make the number a list and iterate through it
but I'm not so sure it'll work like that. I think I need to somehow multiply every set of 13 adjacent numbers, but how to do that, I'm not sure.

2:23 PM
Hello fellow humans

user116211
Yo @bernardo.

@BernardMeurer, hello

user116211
Where is @0celo7?

user116211
I fear he is dead :(

user116211
The election is also coming nearby.

2:28 PM
@MAFIA36790 Probably playing fallout or sleeping

user116211
Ooh; his new profile pic speaks so.

3:12 PM
Caption: Current progress before starting Lie groups proper
Comment: Most algebraic topology and algebraic number theory group articles are incomprehensible
Current location: Hyperbolic group

I'm beginning to feel I have a problem and should seek professional help ...
2

user116211
0

Can anyone help me to find a way to write Fokker-Planck equation for a levy walker in a potential (V) ?

what's with all those laptops?

user116211
Lack of research efforts?

Why are operators always defined on a subspace of the Hilbert space
Why not the whole space

3:15 PM
@JohnRennie, that's not a problem
that's just awesome

They're all mofo 3GHz i7s as well :-)
But I have seriously got to resist the temptaion to buy more :-)

=D

user116211
@JohnRennie You should put them in auction.

I have my own set of problems
especially nonfiction now

@MAFIA36790 sell my babies? You're a sick man!!

user116211
3:18 PM
ooh. Sorry.

I also spend way too much time coding to solve arbitrary problems
like the Euler problems
but I just can't resist
also python...I <3 python

user116211
You should start Halmos by now @heather.

The set theory book? I am indeed reading it

user116211
good.

it is fabulous
thanks again for the recommendation

user116211
3:24 PM
Better thank me after you complete this masterpiece. You will be enlightened by then.

=D I can't wait

user228700
3:44 PM
@JohnRennie Omg xD

@Kaumudi shrug :-)

user228700
Why dyou have so many of them?!

@Kaumudi, hello

user228700
@heather: Hi Heather! :-) How's it going?

user228700
@DHMO: Greetings.

3:46 PM
@Kaumudi hi

@Kaumudi, pretty well. I've gotten re-addicted to the Euler problems. I'm reading through Naive Set Theory. and I'm also procrastinating.

user228700
@DHMO: Haven't seen u around in awhile.

@Kaumudi I'm just in the math chat room

Procrastinating on many things, actually...

user228700
@heather Sounds good :-D

user228700
3:47 PM
@heather Ugh, procrastination. Sucks, amirite? :/

user228700
^Using my phone, keeps autocorrecting, sorry.

@Kaumudi, yeah...it is good while it lasts, and then you have to do everything all at once =( but anyway, I might start working on it now

user228700
Dyou think reading an amahzing article about it might help? It's better than anything I've ever read and it's helped me a lot ever since I read it.

hmm, what is it?

user228700
Hang on, lemme find it...

user228700
3:50 PM
Just watch this:

user228700

user228700
It's a lot quicker than reading the whole article.

okay, will watch, thx

user228700
Sure, no problem. Do let me know if u like it :-)

hello

user228700
3:55 PM
Hi :-)

I'm sick, not sure what to do

user228700
@DHMO Oh, OK...

Just slept for 11 hours
And I should be hungry, but I'm not...

user228700
@0celo7 Dyou have a fever or cold or something?

Cold, I hope
I don't think it's a fever

user228700
3:58 PM
Maybe u sleeping for 11 straight hours doesn't have anything to do with the cold...didn't u say that u're mostly sleep deprived? Your body may just have "caught up" on some sleep last night.

I sleep 7-8 hours every day, I'm not sleep deprived.

user116211
Maybe pneumonia, tuberculosis or may be over dose of some unknown drugs. Anything.

It was because of the cold, I went to bed early
Because of the cold

user116211
You will not die though.

user228700
@0celo7 Oh, OK ._.

user116211
3:59 PM
Just have some hot coffee.

I also just coughed up some mucus the size of a silver dollar...wtf
@Kaumudi Do you think that's sleep deprived?

user228700
@0celo7 No, that's actually pretty good.

user116211
Visit a doc now.

If anyone is interested, the current Perimeter Institute public lecture is on dilatant suspensions. I did a lot of work on these while I was working at Unilever Research.