7:00 PM
@ooolb: well, I remembered it as noise ;).

noise sounds fucked
if it doesn't make your ears bleed then either you have autism or it's not noise.
but that's the point

@Abcd Escape speed represents the parabolic orbit speed at that location. It divides free trajectories from bound ones. Don't get hung up on the verbiage used for introductory treatments.

Aube is a Japanese noise musician
You got a thing for all things Japanese?

nah what do you take me for a weeb?

We're rarely interested in the exact value, but we are interested in knowing that we need delta V for escape, plus transfer orbit insertion, plus destination burn, plus maneuvering reserve.

7:03 PM
Whats a weeb? Is that a new meme?

It's just one part of a bigger picture.

@MoziburUllah a westerner obsessed with japanese culture

Seriously?! The things you learn. What do you call a Japanese guy obsessed with all things Western?

sometimes im a lowkey otaku but i don't make it obvious

Am I supposed to believe "Fourier" is pronounced "Fourieh"?

7:04 PM
if you ask me irl if i watched a certain anime i'd say no even if i did
@MoziburUllah a beew

LOL!
Aristotle said that all philosophers agree that the roots of all things are contraries. So you'd get on fine with him.

@bolbteppa It also helps there there are generally few meaning that make physical sense and fewer still that are interesting.

LOL is a palindrome.

There is a lot of implicit knowledge that goes into reading physics.

Ok. I gotta go to the shop buy some stuff. I'll be back later.
Cheerio.

7:08 PM
@MoziburUllah that sounds sexual

@SirCumference Ugh it was true
My prof lied to us

are you talking to yourself
how many all nighters r u on now

@SirCumference No I'm not
I dunno 0.5 right now

how can you be on 0.5 all nighters

@ooolb Technically it was 0.75 all-dayers
...I think

7:12 PM
what

I dunno I'm tired
I had 3 cups of coffee but I don't think it's doing anything anymore

i always have coffee and it doesn't ever do anything
even when i don't have it i feel the same

@ooolb Ah, it was a half-nighter

$$..............$$
@ACuriousMind quiet today
what's the matter

Anonymous

7:18 PM
> Otaku
Isn't that another name for weeb? (no offense, genuinely thought it was pejorative)

@SirCumference I wouldn't say that it's the nicest of terms to describe yourself with

Urban Dictionary is pretty accurate

God sometimes I love UD
Wait lemme find one of my faves

i bet JD wrote that entry

7:30 PM
This one just cracks me up (Nsfw probs... don't click if you're gonna get sensitive and flag me...)

this is too accurate it's scary

Is this where you got it from?

which one

uhhh no
that's a coincidence
nothing against bloo though
i feel like #3 depicts me quite well

7:33 PM
@ooolb who do you think wrote that

karl rominger

spell that backwards

regnimor lrak
holy fuck

yep
they used to call me Lrak Ocelot.
2
I proved myself in Regnimor. Got the Medal of Lenin there

Am I missing something here.
I feel like I am.

7:36 PM
@CooperCape ... Well... That escalates rather quickly... O.o

@CooperCape 90% sure it makes no sense, don't worry

@SirCumference u wot

@SirCumference It appears similar to something from Thor...

@Mithrandir24601 Ejected from the game though... Tbh learnt a lot about baseball from that.

@SirCumference this is a physics chat
90% aint good enough
sigma 5 or go home

7:39 PM
@ooolb It's sigma 1.6 or so. Engineers would round it up to 2.
Accurate enough for me

(looks up sigma 5 under the assumption that it's $>90\%$)

engineers do 2 sigma? Are you insane

@SirCumference I mean 2 is basically $\pi$ and that's a Greek thing so you may as well say $\pi$ there.

this whole "Engineers use 3 for $\pi$" thing is nonsense. They don't even know the order of magnitude. They just hit the $\pi$ button.

22/7

7:41 PM
See on a good 'ol Casio fx 83GT/99IES you gotta shift+pi that so it's a bit more effot.

@0celo7 I was going to ask "there's a $\pi$ button?"
It's evidently been too long since I used a calculator to do science

I use a calculator often even for pure math

it's just esc-p-esc now

@CooperCape Really, a simple ceiling function will bring it up to 4. Clearly we've gotten to 4 sigma

(I still don't know what x sigma is...)
(I'll play along)

7:42 PM
@CooperCape standard deviations :P

@SirCumference what

Yeah... yeah uh huh.

@ooolb We've just soundly proved that 90% $\approx$ 4 sigma

Pretty much.
And I didn't even know what sigma was until 1 minute ago.

sigma has nothing to do with that

7:43 PM
Any denial is just pedantry

Hater.

it's a measure of how many greek philosophers would approve of what you said
like 1 sigma would be astrotle
excuse that

Think I remember one of my old RS (religious studies) teachers saying my friend would be a good philosopher because "Aristotle was ugly too..."

@ooolb still don't know who asstrotle and astrotle are

that was an honest typo

7:46 PM
dammit

i love me some dry aristotle

there we go

:41562117 Flawless :P

@EmilioPisanty I didn't see that

@0celo7 can you prove it

7:47 PM
@SirCumference thanks. It takes some work.
ah, got it
@0celo7 $\color{lightgray}{\mathsf{(removed)}}$

wait can we still redefine latex commands
or was it nerfed

Sir cumference = Sir pie*d

$\small{\color{lightgray}{\mathrm{(removed)}}}$?

@user685252 Sir ~2D

actually that's too small
hmmm
can't get that font really.

7:50 PM
@CooperCape I don't think mathjax supports arbitrary font sizes
but heck, maybe it does?

you can go \$\small{}\$

@ooolb check discord

i forget how it works
$\renewcommand{color}{test}$

3D sounds better @SirCumference

I accidentally redefined color the other day to "I fucked up" so yea..
$\color{f}$

7:51 PM
@EmilioPisanty oh
now I see

@CooperCape oh, are we breaking mathjax again?
excellent

good way to get the mods angry

@EmilioPisanty Hey, it wasn't me this time!

it's so cold out...

(22D)/7

7:52 PM
Anyway last time it was under the watchful eye of Bernado

@0celo7 yes, that it is

I didn't even know you could...
until he started tryin to

@CooperCape let's just say that MathJax's a bit... lax... in how it interprets \newcommand

Why did Schrodinger choose to kill the cat
When literally any other choice would have worked

7:53 PM
because he was an analyst

Was Schrodinger an analyst?

and in how it behaves if one draws a recursion loop between command definitions

ewh

he hated cat(egorie)s

I don't actually know what he did outside of QM

7:54 PM
@Slereah he was a player

like, say, if you felt like making the mods angry at you, you could define a command \alpha that called \beta, and a command \beta that called \alpha

Threesomes

"Early in his life, Schrödinger experimented in the fields of electrical engineering, atmospheric electricity, and atmospheric radioactivity, but he usually worked with his former teacher Franz Exner. He also studied vibrational theory, the theory of Brownian movement, and mathematical statistics."
Lame

Schrödinger's cat is a thought experiment, sometimes described as a paradox, devised by Austrian physicist Erwin Schrödinger in 1935. It illustrates what he saw as the problem of the Copenhagen interpretation of quantum mechanics applied to everyday objects. The scenario presents a cat that may be simultaneously both alive and dead, a state known as a quantum superposition, as a result of being linked to a random subatomic event that may or may not occur. The thought experiment is also often featured in theoretical discussions of the interpretations of quantum mechanics. Schrödinger coined the...

@Slereah vibrational theory ( ͡° ͜ʖ ͡°)

7:55 PM
> Schrödinger did not wish to promote the idea of dead-and-alive cats as a serious possibility; on the contrary, he intended the example to illustrate the absurdity of the existing view of quantum mechanics.

Yes, I am aware

He'd be rolling in his grave if he knew how many people took his example seriously

but he could have made the experiment give a treat to the cat
or not
and the point would be the same!

Not as dramatic

Optimist test: Do you consider the cat half alive, or half dead?

7:56 PM
@Slereah not quite as impactful

wasn't it einstein who said he'd rather fucking put a bomb in the box to schrodinger?

though here's a good way to make the thought-experiment more impactful:

I seem to recall a similar thought experiment
On the topic of free will
But much nicer

forget about the glass bottle with the poison, just strap the cat's head under the hammer's path

It's just like
Place two carrots at equal distance of a donkey
Which one does he pick!
That would have been much better

7:57 PM
Neither

Schrodinger's donkey

It dies of starvation

So my laptop just decided that it would be just great if the volume button no longer controlled the volume but brought up the task manager! Thanks volume button :D

@Slereah reminds me of ship of theseus

@Slereah in Spanish that would be "el perro de las dos tortas"

7:58 PM
idek who i am anymore

@Slereah We need more Hypothetical Animal Rights Activists in the world

fucking identical particles in qm

@SirCumference To defend Schrodinger's cat and Pavlov's dog

Pavlov was different

Why, because he was a COMMUNIST?

7:59 PM
S--->R

71

"Despite praise from the Soviet Union government, the money that poured in to support his laboratory, and the honours he was given, Pavlov made no attempts to conceal the disapproval and contempt with which he regarded Soviet Communism."
Oh apparently not

Stimulus ---> Response

seventy one

> Nobody really doubts that the presence or absence of the cat is something independent of the act of observation. ~Albert Einstein
So does JD deny QM?

8:02 PM
Does the tree make a sound?

@SirCumference citation needed
I believe in Duffield and the Debunk

Schrödinger's cat is a thought experiment, sometimes described as a paradox, devised by Austrian physicist Erwin Schrödinger in 1935. It illustrates what he saw as the problem of the Copenhagen interpretation of quantum mechanics applied to everyday objects. The scenario presents a cat that may be simultaneously both alive and dead, a state known as a quantum superposition, as a result of being linked to a random subatomic event that may or may not occur. The thought experiment is also often featured in theoretical discussions of the interpretations of quantum mechanics. Schrödinger coined the...

it's my favourite show

Classic Einstein

@Slereah ^ do you like that

8:24 PM
Hi, everybody.

ohai

heya

it's certainly true to say that Schrodinger's conclusion from his cat scenario was not "QM says the world behaves in a way contrary to intuition" but rather "what we think QM says about the world is so contrary to intuition that it can't possibly be the right interpretation"
That, however, tells us nothing about how we should understand QM.
Hence why I always feel a bit impatient when I hear someone say that Schrodinger presented his cat as an absurdity. It's true, but that's a historical question not an immediately scientific one.

Schrodinger and contemporaries understood less about QM than we do now.
Schrodinger's cat is still important and interesting, but it's slightly less magic than it used to seem.

my own touchstone for QM weirdness is Stern-Gerlach

8:38 PM

@Semiclassical But it's not that weird.

(due credit to SMBC)

no, it's not

I blame Newton for gravity
If Newton hadn't invented gravity we could float

8:39 PM
mostly I like that one can describe it by analogy with how polarizers work in optics

no you can't :-)
Not with classical optics, anyway.

SemiClassical?

Put two perpendicular polarizers in a row---no light goes through. Put a third polarizer at some angle relative to both of them---light goes through.

@Semiclassical Yeah.
So?

That's the entirety of the analogy I had in mind.

8:41 PM
oh

@CooperCape Newton nothing. I blame Aristotle for inventing the idea that our natural state of being is to be on the ground.

Ok but with Stern Gerlach, you can put one magnetic field pointing up/down and you get two beams, one going up and one going down. Now you put a left/right field in one of those beams and you get two beams: one going left and one going right.

Aris-thot-le

@Semiclassical Aristotle did not really understand the scientific method.
2

@Blue w/CC @JohnRennie Hey, I wanted to check in on this before it got too late. On further thought, this isn't quite how you should think of Landau levels. Classical orbits in a magnetic field are never cycloids, they're always circles. The heuristic I was thinking of is this:
i.e. a superposition of many circular motions, each with some different quantum mechanical phase (that' s the $e^{ikx}$ factor, which should be handled with care - you might have a definite canonical momentum in the $x$ direction, but the kinematic momentum will differ from that).
it's not perfect, but it helps get some intuition

8:44 PM
@EmilioPisanty classical orbits in a magnetic field alone, anyways.

also, while I'm on old messages

you do get cycloids if you include a perpendicular electric field iirc
E-cross-B drift and all that

@Semiclassical yeah, that too
also hopping semicircles at an edge

right

which are extremely important for current research

8:46 PM
yup. huzzah for protected edge states

@DanielSank: That would be anachronistic. If you popped into a time machine and asked Aristotle about the scientific method I'm pretty sure he'd grok it. Actually, he grumbled somewhere in Physics about his contemporary critics asking rhetorically 'do they think that we do not observe'.

@Blue keep in mind that most useful treatments of Landau quantization tend to be geared towards the solid state, and the 'particles' you're quantizing are really quasiparticles, i.e. joint excitations on the states of many particles, which then act like a single-particle system. The interesting bit isn't increasing in size, but in increasing complexity of the particle, i.e. pushing towards skyrmions and whatnot.

textures and all that, yeah

@MoziburUllah I meant more than his thinking doesn't reflect the scientific method.
He'd grok it if someone explained it, but I think he was so hamstrung by lack of scientific equipment and knowledge that he resorted to just making stuff up.

@Semiclassical textures?

8:49 PM
yeah. that's what that's often referred to as: a skyrmion spin texture

ah, spin textures, yes
speaking of skyrmions, have you got any wisdom on hopfions that you might care to share?

noooope

ah well

@danielSank: I've read his Physics and it doesn't read like he's making things up; its written like a contemporary paper, he talks discusses the finds and suggestion of his predeccesors looking for the strengths and weaknesses and then going to give his own view. Stephen Hawking talks about Aristotle in a Brief History of Time without being patronising. I'm not sure why physicists pick on Aristotle so much.
Susskind does it too.

@Semiclassical I'd quite like to understand this solution better. But it looks like I'll just have to wait for the paper like everybody else.

8:54 PM
He showed that you could do physics qualitatively despite the lack of good equipment.

weird

yeah, it's really cool

I think comparing Aristotle to modern science is just not a fair comparison

I wasn't trying to compare the two...

no, you weren't

8:56 PM
Contrast?

It was the introduction oh his work by Islamic scholars, like Averroes which kicked of the scientific revolution in the modern era; it didn't come from nowhere.

Anonymous
@DanielSank I guess you need to define $\lambda$ in a better manner. "Probability per unit time" isn't a standard term (afaik). According to your treatment, $\lambda$ is the time average of the probability density function. And $\lambda \Delta t$ gives an approximate value, not the exact (which I'm happy you addressed in your PSE post).

Anonymous
Also, it would be nice if you use $\Delta t$ instead of $dt$ there, since writing $dt=T/N$ looks a bit handwavy to me ($dt$ being a differential). You can later take $\Delta t \to 0$ and $N\to \infty$.

Anonymous
Feel free to give any counter arguments you might have, I'm interested

@Blue In the first part of the answer, I never used $dt$ to mean anything other than a finite time interval, so there's no hand-waving.
Perhaps the notation is confusing though. You can edit to use $\Delta t$ if you like.

Anonymous
8:59 PM
@DanielSank Yeah, that would be nice :)

No one can see you waving your hands on the internet :P

Anonymous
Also if you could define $\lambda$ properly in the post...

@Blue It is defined just fine.
The probability of an even happening is $\Delta t \lambda$, as long as $\Delta t \lambda \ll 1$.