The h Bar

DanielSank

6:04 PM

@vzn I'm taking off soon. Let me know if you want to talk about silicon qubits.

Slereah

(this will be used to spell Christmas cheers)

DanielSank

^ I like it

JamalS

I was trying to set a bounty, and the minimum is +200, despite the fact there are +50 bounty questions currently on the site. What's up with this?

DanielSank

No idea.

Slereah

Also some red and green blinking LEDs, and I'll try to use a PC speaker for Christmas music

DanielSank

6:08 PM

@JamalS which question?

Slereah

Also a photoresistor to only start when the package is open

Anonymous

@Slereah Nice. You are gonna put the equipments in some casing, no?

Slereah

the nice thing about the LCD screen is that it's a circuit in itself

So no worrying about resistances

@Blue well the gift is more the Arduino itself

So probably minimal casing

Anonymous

You're just going to gift the Arduino, and not the whole setup? :P

Slereah

Well the whole setup

But ideally the arduino be recoverable from it

Anonymous

6:11 PM

Oh, I see

Anonymous

Good idea for a gift though

Anonymous

You could add some sound effects as well :D

Slereah

I will, yes

Well, I'll try

With a PC speaker

and some attempt at an arduino Jingle Bell

CooperCape

@DanielSank Getting my four brothers to joint buy me Artin linear algebra for christmas so maybe sometime after that :p

DanielSank

@CooperCape Sure. Make sure that at some point, the following statements make sense to you:

1. A matrix is just one representation of a linear transformation in a particular choice of basis.

vzn

6:14 PM

@Slereah this seems cool have you seen it? kano pixel kit think it uses raspberry pi... like the spectrum analyzer :) medium.com/retronator-magazine/…

DanielSank

Actually, just that.

That is important.

@vzn Did you see the photo I posted the other day?

You're an electrical engineer, right?

vzn

@DanielSank software engineer. which photo?

DanielSank

Oh, it was a photo of a circuit board I recently finished.

Thought you might enjoy some pcb porn ;-)

vzn

in theory salon, yesterday, by vzn

New silicon structure opens the gate to quantum computers / physorg

@DanielSank enjoyed mithrandirs diagram did you see it?

DanielSank

Link?

vzn

6:18 PM

@DanielSank xkcd chat.stackexchange.com/transcript/71?m=41763340#41763340

@DanielSank am sure yours are even more beautiful/ elegant ;)

DanielSank

@vzn Oh, hah. I've seen that.

Slereah

I've got like 4 days to make this and I don't remember that much electronics

A challenging thing

DanielSank

@vzn Meh. Dunno about that, but mine has octopuses in the silkscreen.

Slereah

Fortunately most of it is digital stuff

DanielSank

Здравствуй, @Mithrandir24601

Slereah

6:19 PM

No need to worry too much about voltage

CooperCape

@DanielSank Yah I get that... (sadly things seems to get more complicated than that though :/)

vzn

@DanielSank silkscreen for electronics? (octopuses rock!)

DanielSank

@CooperCape Actually, that one principle will get you very far in physics.

@vzn Yes, pcb's have a silkscreen pattern that says things like C2 or 3.3V or Eagle v2 Daniel Sank Google Inc., etc.

CooperCape

So it's just a lil' bit handy then...

vzn

@DanielSank ok thought that was tshirt technology :)

DanielSank

6:23 PM

@vzn See here

Also, @vzn what was with the frogs you posted yesterday?

Mithrandir24601

@DanielSank ni hao!

vzn

@DanielSank they are ~~mudsuckers~~ mudskippers found em on a pg, just felt strange urge to share with group... and then strange synchronicity that your resume was last line... a real life version of the :o emoticon eh? :P dailymail.co.uk/news/article-5178463/…

CooperCape

I swear the only foreign greeting I know is "Hallo" for german...

DanielSank

Let's See:

Mithrandir24601

@CooperCape ¿hola?

CooperCape

6:29 PM

@Mithrandir24601 Oooh you're so continental ::blushes::

DanielSank

English: Hello
Spanish: Hola
Russian: здравствуй
Greek: Για σου

I think that's all I got

French: Bonjoir (spelling?)

CooperCape

I think Mithrandir's said ni hao enough times for me to know it's ummm where did mithrandir go again... he hasn't mentioned it before...?

Sid

@CooperCape China

Mithrandir24601

@CooperCape oh, not very far - just a short hop on the plane :P

Sid

@DanielSank Bonjour

CooperCape

6:31 PM

Well well well...

Slereah

holy shit

I dropped some wires on the arduino and it shortcircuited and started smoking

Good thing those things are shortcircuit resistant

was worried for a bit

CooperCape

smoking kills.

DanielSank

@Slereah I doubt it still works.

Slereah

Nah

DanielSank

If it smoked, something bad happened.

Slereah

6:34 PM

Not the first time I shortcircuit it

though the smoke is worrying

Let's check

DanielSank

That's... impressive.

Slereah

I mean the LEDs on the arduino still work fine at least

DanielSank

@Slereah skeptical face

Slereah

On the other hand, the USB port doesn't seem to, anymore

Fuck

DanielSank

The smoke is what makes electronics go. If you let it out, they can't work any more.

@Slereah Theeeeere we go

Slereah

6:36 PM

Oh well

Good thing I've got a spare

I guess now I just have a very fancy generator with pins :p

The pins still output current fine, I think only the USB plug is fried

not quite sure what happened

Anonymous

My Arduino's USB port burnt too, last week. That's an usual problem with non-original Arduino boards

CooperCape

I accidentally spilt yoghurt in a usb port once

Anonymous

Occasionally it works...but more often it doesn't, now

Slereah

I dropped a bunch of jump wires on it, I think one of them touched a bad thing and bam

DanielSank

@Slereah This is going to sound a little funny, but it's actually really, really helpful to manage electronics workspace the same way you would manage your kitchen while cooking.

Slereah

6:39 PM

I'd better be careful with the remaining arduino

Otherwise it will have to be a box of chocolate or something

DanielSank

Keep your station clear

►

This is some of the best advice anyone can get about the ergonomics of working on electronics.

Slereah

We have display

DanielSank

Nice.

Loong

@DanielSank FME Zone 1?

DanielSank

(Those wires could be a lot shorter. They're begging to get snagged on something and whip your board off the table.)

@Loong wat?

Hi, @knzhou

knzhou

6:41 PM

hey!

Slereah

I think I'll order like

a bunch of arduinos

Just in case

Loong

@DanielSank That's the highest Foreign Material Exclusion level in a nuclear plant.

Slereah

Since they're cheap as dirt

Anonymous

@Slereah What!

Slereah

Well

Comparatively

Anonymous

6:43 PM

I mean original ones are pretty expensive

Slereah

Psh

Who buys original

You can just get like 5 chinese ones :p

Balarka Sen

getttttt dunked onnnn

knzhou

@DanielSank I ended up taking res.cls and a couple of your macros. the result looks great!

now i'm working on making publications work with BibTeX.

Anonymous

The Chinese ones don't last long :P

Slereah

ebay.com/itm/…

Such bargains!

@Blue Well you know how it is

Anonymous

6:44 PM

@Slereah lol

Slereah

If you fry an expensive thing

It's much more of a pain than a cheap one

Anonymous

The expensive ones don't get fried easily XD

Anonymous

But well, as you wish

Slereah

Trust me

i'm very capable of frying an expensive thing

Anonymous

BTW I have just accepted I'm terrible at experimental stuff and suck at handling equipment in labs. I should just stick to theory

Slereah

6:46 PM

Same :p

Anonymous

@Slereah hehehe

Sid

@Blue lol.

Mithrandir24601

@Blue Ahh, a few years back, I was able to do experiments. Then I took an arrow to the knee

Slereah

Hm

Having trouble inputting data on the LCD

CooperCape

I've never been good at experiments (but I'm still at high school so there's hope...)

Slereah

6:58 PM

argh

It's just not writing

why not

Hm, there might be timing issues, i think?*

Like the enable pin should maybe only get a very short signal

Anonymous

What's the problem?

Anonymous

Code not uploading?

Slereah

I'm not using code right now

just doing it raw

DanielSank

@knzhou Glad it helped.

Slereah

When I connect the enable pin the characters don't get written on screen

DanielSank

7:02 PM

@Loong Oh, heheh, now I get it.

Loong

:-)

Anonymous

I see. Hope your LCD is not faulty. Also, I'd check if there are some errors in the code.

Anonymous

Here's an example instructables.com/id/…

Slereah

Oh wait, maybe I need to send an instruction?

I dunno

Anonymous

Also, the wiring may be faulty

Anonymous

7:03 PM

Check the connections once

Slereah

I tried using the wire directly on the solder :p

still no

Anonymous

Uh, strange

Slereah

I think maybe I need to send an instruction first?

To trigger the writing mode

mb

Anonymous

That should be in your code, already

Slereah

"code"

Did you not read

About the frying :p

I'm doing it all in wires

Slightly more challenging

ah yes, there's an initializing sequence to do

Hm, seems like it would be ass to do by hand

Let's get out the other arduino and try to not fry it

the other one still smell burnt

enumaris

7:11 PM

sneeze

0celo7

@Slereah any idea where a "Tadeusz Iwaniec" could be from?

Hungary?

Slereah

Eastern Europe i guess

mb yeah

enumaris

isn't there a machine learning algorithm that can classify names based on country of origin

try that

Anonymous

Just put it in Google

Anonymous

:P

Anonymous

7:18 PM

Tadeusz Iwaniec

Tadeusz Iwaniec (born on October 9, 1947 in Elbląg) is a Polish-American mathematician, and since 1996 John Raymond French Distinguished Professor of Mathematics at Syracuse University. He and mathematician Henryk Iwaniec are twin brothers. == Awards and honors == Iwaniec was given the Prize of the President of the Polish Academy of Sciences, 1980, the Alfred Jurzykowski Award in Mathematics in 1997, the Prix 2001 Institut Henri-Poincaré Gauthier-Villars, and the 2009 Sierpinski Medal of the Polish Mathematical Society and Warsaw University. In 1998 he was elected as a foreign member of t...

0celo7

what is Google?

Anonymous

Put that in Google too

enumaris

I think building a ML algorithm for names is gonna be cooler

0celo7

let's see what Bing says

hmm, Google seems like Skynet

not good

Slereah

All hooked up

Anonymous

7:20 PM

Even Microsoft employees use Google. Get over Bing

Slereah

This better work :V

0celo7

nuclear physics grade got curved into an A, yippee

Anonymous

congruts

enumaris

aren't u a maths guy now

just do them maths?

Anonymous

@enumaris He just transformed a few days ago

enumaris

7:22 PM

uh....

0celo7

@enumaris I needed an A in that class to count as credit for something else to graduate

Anonymous

From $\text{NE+Math} \to {Math}$

0celo7

@Blue and a physics minor

Anonymous

@0celo7 Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh‌hhhhhhhhhhhhhhhhh

0celo7

wot

Slereah

7:23 PM

Hm, Arduino has an LCD library

That should help

Anonymous

Your hate for physics isn't strong enough :P

0celo7

I have said many times that I hate physicists, not physics

Loong

@0celo7 Need a job? ;-) We start HFT tomorrow.

0celo7

@Loong I'm not longer a nuclear engineer

enumaris

hmmm

Slereah

7:26 PM

Still doesn't work ;w;

0celo7

crap

enumaris

usually u only need a C to get credit, no?

Anonymous

@0celo7 Hmm. Things depends on what you consider to be the line between physics and mathematics, then. Do you consider ACM to be a physicist or mathematician?

0celo7

just got star wars spoiled

enumaris

Now the requirements is A for credit?

0celo7

7:26 PM

@Blue he's a computer programmer

Anonymous

@0celo7 Lol. Not yet. He hasn't joined the company

0celo7

@enumaris if you're substituting a class for something else in the syllabus, yes

enumaris

hmmm

what an odd system

0celo7

idk it might not be a requirement, but they said if I get As then there's no issue

otherwise I'd have to to talk to them again

enumaris

I see..

Slereah

7:32 PM

Let's try the other LCD screen

wait no

The other one isn't a 16 pin screen

fuck

Well, let's try to work the PC speaker, in the meanwhile

0celo7

alright, need to make lesson plans

Slereah

Slightly challenging because I have no idea what that PC speaker is

So not a clue what current it needs

dx.com/p/…

Seems to be this one

0celo7

time to work on the thesis

oh no, too much to do

Slereah

well the buzzer works, at least

Now to try and make a little music program

0celo7

@Slereah Where would I go to see a physicist talking about the Noether theorem

Slereah

7:44 PM

piano-keyboard-guide.com/…

Perfect

@0celo7 A variety of places

Depending on how you want it

0celo7

Not sure exactly how I want it

Too much stuff to do

Slereah

Beep

►

such sweet music

My other PC speaker does sound better

Well I can play the notes of the song, but the hard part is gonna be the timings

Balarka Sen

8:03 PM

play Mans Not Hot

Slereah

I hope I figure out what's wrong with the LCD

Beep2

►

So far so good

I guess I'll have to try to find out how the 4-pin LCD screen works

It would be nice to be able to get musics as a list of frequencies and lengths

Converting it from keys and gut feeling is a bit tedious

I guess I could rip a MIDI file but it's about as tedious

DanielSank

8:19 PM

Hi, everybody.

New rule:

DO NOT SPOIL STAR WARS IN THIS CHAT

^someone perma-star that, please.

@JohnRennie

Slereah

SPOILER DARTH VADER IS LUKE'S DAD

DanielSank

-_-

In other news, I have no hats.

Slereah

you can get one at most shops

As you all know I have a hat

2 days ago, by Slereah

DanielSank

I learned something today that caused my brain to temporarily shut off.

Suppose I have a resonance mode that decays exponentially, i.e. $\exp(-t/\tau)$.

0celo7

@Slereah doesn’t matter

DanielSank

8:23 PM

It is somewhat common to refer to a decay rate $\kappa \equiv 1/\tau$ so that we get $\exp(-\kappa t)$.

Here's the crazy thing: the second equation is right, but the first equation is very misleading.

The thing is, $\kappa$ has dimensions of radians per time.

Calling $1/\kappa$ a time is kind of wrong.

This completely blew my mind.

CooperCape

@DanielSank Phys SE is slacking on hats

DanielSank

@CooperCape I was really excited about the hats last year.

CooperCape

Phys SE is 17th site in terms of numbers

DanielSank

But then they took my hats.

CooperCape

Awww

DanielSank

8:25 PM

It's hard to get excited again.

Slereah

But radians are dimensionless :0

CooperCape

I only got one cause Ivoted to close a question

I think.

DanielSank

I had a tophat that sat very elegantly on my octopus head.

I've done edits, voted on stuff, etc. etc. and still no hats!

CooperCape

That hat requires too much on others not doing things (top hat) iirc

0celo7

8:41 PM

@Slereah or are the dimensions radians

Slereah

Radians are just $m/m$

CooperCape

metres per metres seems legit

Slereah

you know what's a totally fake dimension in SI units, though

Moles.

Why not call the number 2 a unit

CooperCape

lmao

A copper sulphate solution of 0.5 2's/dm^3

I can't see it catching on...

DanielSank

@Slereah Some dimensions exist because of the realities of experiment.

Temperature is such a thing.

Temperature should just be energy, but it's not because measuring the internal energy of a gas is really, really hard.

Slereah

8:48 PM

temperature is also a fake dimension

DanielSank

@Slereah Only sort of.

See here:

30

Q: Is the Boltzmann constant really that important?

I read a book in which one chapter gave a speech about the fundamental constants of the Universe, and I remember it stated this: If the mass of an electron, the Planck constant, the speed of light, or the mass of a proton were even just slightly different (smaller or bigger) than what they ac...

CooperCape

1.38064852

Love you boltzy

Mithrandir24601

It's a constant, so surely it's just 1?

Slereah

The constant that I find the easiest to remember is the electron charge

DanielSank

::blood boils::

Slereah

8:49 PM

Because it's 1.602

DanielSank

@Mithrandir24601 YOU CUT THAT OUT!

Slereah

and that looks like IGOR

in Leet speak

Mithrandir24601

@DanielSank :P

Oh, I just read that: "Of course, as I said in the answer, it makes the most sense to make kb dimensionless, and pick the value 1."

@Slereah what, 1 eV?

Slereah

No, just the charge of one electron

1.60217662 × 10-19 coulombs

CooperCape

Speed of light is just a classic one to remember

Anonymous

8:52 PM

@Mithrandir24601 Just 1e :D

@CooperCape 1c

just planck units it

@Blue yeah, i.e. 1

1

@CooperCape exactly

8:53 PM

That's boring though

Mithrandir24601

@Slereah =1

CooperCape

I just set constants as my password to remember them

Anonymous

If engineers knew this, they'd be very happy

Anonymous

$\pi=e=1$

Slereah

Actually the electron charge should be -3

That way we can set quark charge at 1

Mithrandir24601

8:53 PM

@Blue this on the other hand is a travesty

CooperCape

waaait a second

Anonymous

@Mithrandir24601 Bad joke

CooperCape

Sep 3 at 10:35, by CooperCape

@user400188 All those engineers like $\pi=3=e$

heh

Slereah

CooperCape

::feels predictable::

DukeZhou

8:57 PM

rofl

DanielSank

@Mithrandir24601 Yeah, see, making something dimensionless is different than "picking units where $c$ is 1".

Units and dimensions are not the same thing.

Every constant = 1

^

Except mass

@DanielSank hmm... Yeah... It can still be 1 though :P

bolbteppa

9:05 PM

Dirac equation with $m = 1$ is just weird

Slereah

@bolbteppa all is one

Mithrandir24601

@bolbteppa 'mass' by itself isn't a constant though... It's not like you can just set energy = 1...

bolbteppa

It's constant enough :p

DanielSank

@Mithrandir24601 My teacher said mass was conserved i.e. it can never change so mass is constant right?? ? Can someone help me understand this plz!

Mithrandir24601

@bolbteppa OK, let me rephrase: mass of electron $\neq$ mass of the sun. Therefore mass isn't constant

I'm beginning to believe that you're meaning something somewhat different to ^ :P

DanielSank

9:12 PM

But mass is conserved so you cna't be write!

Mithrandir24601

@DanielSank I cna write be!

Slereah

9:24 PM

@Mithrandir24601 proof?

Mithrandir24601

@Slereah The sun is erm... Big and erm... ::panics:: ... ::runs away::

3

DanielSank

9:42 PM

Is there a useful expression for $$\cos(x)^2 + (1+\epsilon)\sin(x)^2 \, ?$$

Oh never mind.

DanielSank

9:56 PM

I got a hat!

ZOMG. I can get an awesome hat from this answer. Yes, that's shameless, and no, I don't care.

enumaris

hmmmm

DanielSank

10:24 PM

@enumaris yes?

enumaris

I'm wondering why weight_decay is having no effect on my loss...lol

DanielSank

@enumaris weight_decay?

enumaris

pytorch.org/docs/master/optim.html

It's basically the L2 regularization parameter

It should increase my loss...but it's doing nothing...

very odd

bolbteppa

Quotition and partition

In arithmetic, quotition is one of two ways of viewing fractions and division, the other being partition. In quotition division one asks how many parts there are; in partition division one asks what the size of each part is. For example, the expression 6 ÷ 2 {\displaystyle 6\div 2} can be construed in either of two ways: "How many parts of size 2 must be added to get 6?" (Quotition division) One can write 6 = 2 + ...

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