The h Bar

Slereah

14:10

that's why I don't usually believe in huge intricate conspiracies

people aren't very good at secrecy

0celo7

@Slereah but Alex Jones says they're true

@Slereah it's not like people believe the leakers anyway

Slereah

Let's look on linkdin if anyone works on the gay frog agenda

Emilio Pisanty

@Slereah @JohnRennie I don't understand why you're so focused on Fock states, btw

0celo7

The moon landing was faked

Emilio Pisanty

sure, they're not localized, but neither are non-relativistic eigenstates of a single QM particle

Slereah

14:12

@EmilioPisanty Well yes

That's what I'm saying

Emilio Pisanty

and it's perfectly possible to take linear combinations of Fock states that have well-defined single-particle character, are not eigenstates of the hamiltonian, and are localized

Slereah

Well obviously, yes

Since they're a basis

But when I think "particle", I think more "coherent state"

That's a much better approximation

Maxime

yo

is it allowed to make a discussion about homework-questions?

Slereah

The chat has no rules on topic

Emilio Pisanty

@Maxime what do you mean exactly? and where do you want this discussion to take place?

Slereah

14:17

So you will only get social condemnation if you ask the wrong thing

Emilio Pisanty

if you mean whether it's OK to discuss the policy on homework questions here on this chat, then yes, it is allowed

Anonymous

Gosh. Please DON'T discuss homework policy. It takes a toll on everyone's brain. :P

Emilio Pisanty

"I found out that space and time are basically one and the same thing" - but this isn't true just as rulers and clocks are not basically one and the same thing. — Alfred Centauri 2 mins ago

^ fantastic

Slereah

Damn spacetime signature

Emilio Pisanty

@Slereah I tend to work in a ++++ signature

keeps things interesting

Slereah

14:20

That's fine if you're in flat space

or you're doing string theory, I guess

Emilio Pisanty

=P

curved space just makes me go ¯\ _(ツ)_/¯

no, honestly, though, I tend to work in $\mathbb C^4$

I don't know what signatures are

Slereah

Gregg Egan has a whole thing on curved spacetime with a ++++ signature

It is interesting

Signature is the sign of the eigenvalues of the metric

Emilio Pisanty

@Slereah no, as in, in my work there's no metric and therefore no signature

Slereah

Oh

what do you work on

Emilio Pisanty

I do have complex-valued times and complex-valued trajectories, though ;-)

0celo7

14:24

@EmilioPisanty :/

Riemannian geometry is the reason why most modern math was invented

Emilio Pisanty

@0celo7 ¯\ _(ツ)_/¯

0celo7

Excluding algebra

Emilio Pisanty

GR is pretty and all

but QM is better

@Slereah more specifically, I work on ways to have trajectory language for dynamics that involve the tunnel effect. And since $v^2<0$, you have $\frac{dx}{dt}$ imaginary, which is nice and easy to do if one or both of the factors is imaginary.

Slereah

Non-relativistic QM is fine

it is QFT that is awful

0celo7

@EmilioPisanty am I weird for being into QM and GR separately (QM is more of a hobby) but hating anything that tries to mix them?

It's a phrase with bad history, but "separate but equal" describes my feelings on the issue

Emilio Pisanty

14:29

@0celo7 I think it's an OK attitude to have

Slereah

Is there any description of RQM in curved space?

Emilio Pisanty

dunno about "separate but equal" tho

Slereah

That's probably easier to deal with than QFT

Mithrandir24601

@EmilioPisanty oh, nice!

0celo7

@EmilioPisanty why not

You've never heard the phrase?

@Slereah ew

Emilio Pisanty

14:30

@0celo7 I have. that's the point.

0celo7

@EmilioPisanty I don't think that should ruin the phrase.

Emilio Pisanty

@0celo7 ¯\ _(ツ)_/¯ if that's how you feel then anything I say about it is unlikely to convince you or lead to a constructive discussion

Slereah

@0celo7 Free RQM is mostly well defined

Maxime

lmao

I wonder how they wanna get some effort for questions

imagine that someone doesn't have any idea about the question

and doesn't wanna get the final answer

0celo7

@Slereah people have studied the Schroedinger equation on Riemannian manifolds a bunch

Anonymous

14:33

@0celo7 It's a bit strange. Most physicists I meet in the real world seem to like QM more than GR. It's opposite for mathematicians. Dunno why

0celo7

I think you've done that too

Slereah

@0celo7 I know, I did it

That was my master thesis

Maxime

ngl

Slereah

But I mean RQM on spacetime

Maxime

let mathematical

questions be on

math.se

to me this physics.se is waste of time

for mathematical questions

Emilio Pisanty

14:33

@Maxime (at the risk of implying that I'm interested in a long-winded discussion, which I'm not) who's "they"?

Slereah

@Blue Fairly simple

GR is well defined mathematically

Anonymous

@Slereah Is GR more mathy?

Slereah

It is

Anonymous

Ah

Slereah

There's a lot of shit in it

Maxime

14:34

ngl i had posted my 7 questions here

Anonymous

I guessed so XD

Maxime

all shits became off topic

lmaoo

Slereah

QFT is also very mathy but it's also a lot more handwavy, quite often

Maxime

0

Q: Cluster Approximation for the Two-Dimensional Ising Model

In the attachments there is the question and its solution, it's problem 3.5. My question is how did they get the dimensionless Hamiltonian in both cases, and how did they explicitly calculated $m$ in both cases? I assume it's with $m = \frac{\sum_{\sigma_i}\sigma_i e^{-\beta H}}{\sum e^{-\beta H...

party is starting guys

Anonymous

Another reason is perhaps GR doesn't have much real world application as of now

Maxime

14:35

it will be off topic

in a sec

Slereah

Tell that to my GR bomb

Maxime

or something rofl

Anonymous

@Slereah I'm waiting for things like General Relativity engineering to come up :P

Slereah

There's papers for GR engineering

It's just not doable with existing technology

or maybe not doable at all

0celo7

Penrose mechanism

Slereah

14:37

that too

Sir Cumference

Whatever happened to ACM?

Slereah

Also all the warp drive and wormhole stuff

Baby universe stuff

Antigravity

It's a bit hard to do though

0celo7

@Slereah @Blue QM is perfectly well defined and lots of mathematicians work on it. The modern stuff is more linked to operator algebras and is rather abstract.

Maxime

if your question

is about mathematical physics

Slereah

Yeah, QM is fine

Maxime

14:38

post it on math.se

0celo7

@SirCumference I'm sad to say that @ACuriousMind is no longer with us. He lagged out of existence.

ACuriousMind

@SirCumference Nothing

Slereah

I almost did my thesis on QM math

But alas it was not to be

Maxime

you can get great answers there ;P

0celo7

@ACuriousMind holy shit

Slereah

14:38

With non-relativistic QM supersymmetry

0celo7

@ACuriousMind you didn't comment on my feta and I'm quite hurt

Maxime

0

Q: Force on a solenoid?

A solenoid with a current $I$ experiences an outward Lorentz force owing to the magnetic field it creates inside. Assume that a solenoid with radius $R$ and $n$ turns per unit length is aligned with the $z$ axis. Now I try to calculate the total force exerted on the right half (divided by the $xz...

homework-and-exercises electromagnetism magnetic-fields

look at this question

why these moderators being funny

ngl this physics.se waste of the time

Anonymous

@Maxime Why are you advertising math.se ? XD

Maxime

lol everyone getting great answers

but look at physics.se

%90 of questions being off-topic or something

i've seen chemistry and biology.se as well, they were great tho

Anonymous

Yeah, because the policies here are a bit different from math.se. We don't give out free hw answers.

Maxime

14:43

yeah ''policies''

they aren't giving free answers

Anonymous

That has been debated several times and it's not going to change. No use complaining.

Maxime

nobody wants free answers lmao

you guys see it like that

who wanna get free answers from u lol?

idk this site is waste of the time

I've seen all policies about se community

this is not reasonable

Emilio Pisanty

@Maxime Is there some specific point you want to make and/or something specific you want to ask?

Maxime

I can ask my questions here

Anonymous

@Maxime Yeah, but you are wasting your time at the moment, complaining. You can raise your specific concerns on meta.

Maxime

14:46

lol its not hard to google it

what do you mean by ''specific questions''

I wonder it ngl

Anonymous

@Maxime There is a room for problem solving strategies. You can ask there if you wish. You could also try asking your questions here (but if you dump hw questions without effort no-one is going to answer).

Emilio Pisanty

@Blue Don't feed the troll.

Maxime

Emilio

Anonymous

@EmilioPisanty Agreed

Maxime

I think the real troll is you

what does mean ''specific questions''?

it's not hard to google it ngl

can get an answer in a sec

Emilio Pisanty

14:48

@Maxime What is the purpose of your conversation right here, right now?

Are you here to rant?

Maxime

im tryna make it better.

with good ideas.

Emilio Pisanty

@Maxime These good ideas of yours, they take into account the preferences of people who actually provide answers on this site?

0celo7

@EmilioPisanty you're doing the feeding now

Emilio Pisanty

@0celo7 yeah, I guess I was.

Maxime

this is just an idea

Emilio Pisanty

14:50

@Maxime Post it on meta.

Maxime

what do you mean by ''feeding''?

im not troll

Emilio Pisanty

Just make sure to catch up on the previous discussions

there's a handy list of links at the start of this answer

8

A: Why can't the Homework policy be more lenient?

The "homework policy" has been a source of tension on the site for a long time now. (A helpful editor could probably turn every word of the previous sentence into a link to a different Meta discussion about homework-like questions.) I think that everyone agrees that zero-effort homework questions...

Maxime

aahhahahahaha

Question

[blurry photo of assignment]

plz halp

Answer

teh answer is 15.6

don't think everyone like this

I don't talk about these troll guys

0celo7

I wish my homework was like that

Maxime

or who wants free solution

then

let someone be like

Emilio Pisanty

14:52

@0celo7 if you want your homework to be blurry, then you can just take a photo, blur it, and then print that

Maxime

hmm

0celo7

@EmilioPisanty I mean it would be nice if "15.6" was an acceptable answer

Maxime

What if we give the equations that he/she need

he/she will show some effort to solve it.

0celo7

@Maxime I agree with that.

Maxime

exactly.

Emilio Pisanty

14:53

@0celo7 ah, well

Maxime

Okay let's discuss about this

Emilio Pisanty

change to engineering or something

0celo7

SE has an insane homework policy, no doubt. But it's not going to change. Many people have tried.

@EmilioPisanty I am an engineer

Maxime

A: I've problem with this. What would the correct equation we need use?

Emilio Pisanty

@0celo7 I know =P

Maxime

14:54

B: Use ...... then you will get ......

he/she will show some effort to solve it

if he/she doesn't know enough, won't be able to do it.

Anonymous

@Maxime That's why it is encouraged to ask such questions in chat. There is a dedicated room for that too. It's just not allowed on the main site and that is not gonna change (unless you can make a plan to set up a revolution....the PSEHW revolution or something like that)

Maxime

Can you be more clear?

If someone agree with me

Am i wrong at this?

Emilio Pisanty

@Maxime there's a problem with your idea

Maxime

What is it?

Let's discuss about it.

Emilio Pisanty

that the people who answer questions don't want a site that does that kind of thng

Maxime

14:56

It's not hard to show him an equation.

He/she will show his/her research effort as well.

and will share his/her ideas with us.

then we will answer it.

Emilio Pisanty

@Maxime here's a genuine question for you

Maxime

this currently seems good idea

Emilio Pisanty

do you really think you're the first person to come up with that proposal?

Maxime

I'm not first. However, I think that I'm showing the best ideas for that homework questions.

Emilio Pisanty

@Maxime ... and you're not interested in what the response was when it was first proposed?

Maxime

14:59

what do you mean

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