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1:25 AM
Starting to make sense of these trajectories
do they just zoom by
The hydrogen atom energy levels can be written as $E_{n,l} = K^2 = \frac{1}{(n+l+1)^2}$, (where $K = \sqrt{2mE/\hbar^2}$ arises in the Schrodinger equation naturally). The outer-most line is the $n = 0$ case of $l$ plotted against $E$, next line is $n = 1$ etc...
States with fixed $n$'s and different $l$'s are like different states of an electron. I posted above a diagram of the isotropic harmonic oscillator with the same thing going on, but straight lines.
Mesons, which have no simple 'Coulomb potential schrodinger equation' that we can just solve and then list the energy levels, still satisfy this kind of behavior, only now (relativity) different mesons i.e. different actual particles are the nodes on the line of fixed '$n$' with different $l$ values, plotted against $k^2$, which in relativity is now $E^2 - p^2 = M^2$ hence those $J = \alpha M^2 + b$ plots
Since there's no simple Schrodinger equation we can just set up and solve, people worked backwards from this idea that we know the spectrum, lets find the equation/theory which gives this spectrum, and lo and behold they got bosonic strings somehow
They zoom by from node to node I guess :p (but fixed along the same line)
Still pretty jarring to think of getting different particles along these lines, would you call the $l = 1$ and $l = 2$ states of an $n = 4$ electron different particles...
3 hours later…
4:32 AM
well in a way...
since elementary quantum particles have no substructure, changing its quantum numbers is the same as changing the type of particle, so it is intuitive to me that different states can be identified as different particles
2 hours later…
6:45 AM
Morning to everyone :-
2 hours later…
8:56 AM
@ACuriousMind a job offer for you
1 hour later…
10:08 AM
Dec 3 '19 at 17:26, by ACuriousMind
I firmly believe COBOL is the future
@ACuriousMind unfortunately true
COBOL is like the appendix or catholicism
A relic of another era that we cannot get rid of
My holy neural network is generating theological insights at a speed unmatched!
Pretty slow, but I assume much faster than the usual writing of holy books
@Slereah Careful, lest it produces a second TempleOS
Also hopefully it won't gain consciousness and become god
"In the beginning God created the heavens and shut the gates of the Universe. Open to God! Go on before the wisdom; provide those with eyes. He is good, as recorded in the Docum, and besteth over the wisdom. Believe on a Promised Day; be determined in a righteous anger. Bar the gates of the Protected Field; call the greater done. What this state of the glory of the Almighty is to the divine being, so much the better!"
Even the universe is under quarantine now
Does anyone actually understand reciprocal lattices, or do people who work in solid state just get good at bluffing?
who knows
10:23 AM
all understanding is bluffing :P
I once quoted that von Neumann quote about people not understanding mathematics and just getting used to it on the math channel
they got very angry
A student has just asked me about reciprocal lattices because they baffled him completely. The best I could offer was to say me too.
hand wave, hand wave, Fourier transform, hand wave, hand wave
Why is solid state physics soooooooooooooooooo hard?
Were it not it wouldn't be physics
@JohnRennie I mean, they're just the Fourier transform of the "real" lattice. In my experience many people are just rather bad at explaining that and try all sort of "intuitive" explanations that fall apart if you look at them too closely
there's no physics field for matching block shapes into holes of the same shape
10:29 AM
@ACuriousMind that's easier to say than it is to intuitively grasp :-)
If you wanted to intuitively grasp something you should have gone into making stone tools
There is no intuition (except that gained simply from familiarity with it) - it's a pretty abstract construct
I mean, this part of solid state physics is basically using all sorts of statements from Pontryagin duality but rarely mentions that because math might scare people :P
They are already scared - trust me on this :-)
I remember also being frustrated by these lattices because you were expected to compute all sorts of stuff in them without a really satisfying explanation of why it worked because the lecture didn't like proofs that were longer than two lines
@Slereah Not sure - is there a good intuition for the correct shape of a stone knife? :P
@ACuriousMind sharp
10:35 AM
I know an archaeologist who will not shut up about the surprising intricacy of the different ways you need to shape the stone for different purposes if you get him started on it...
Sample from the holy network : "Every step of the way, a mountain will grow taller and taller, like a piece of the boulder, where the head of the caveman is. When the caveman will be forty, the body of his wife will become like a shield of gold, and his head like a campfire."
Wise words
It almost makes sense until you try to understand it :P
I mean
It makes about as much sense as the holy texts it is made from
It's no less nonsensical than say, Revelations, or the Nostradamus prophecies
"It is the time of the darkening moon, his eyes shine with a darkness that none can describe.
When the children will be seven years old, the virgin when she will be about four hundred years old.
When the caveman is eight hundred years old, and when he will be seventy, he will all that time govern the land, excepting the valley of the mountain, which the mountains are. Then he will lead his people from the valley, to the land northward.
There they will live for forty generations, excepting the hills, and mountains built up by the water.
The caveman gospel
I had to exclude some holy texts because I wanted texts to be mostly readable by modern viewers
So no Pyramid Texts, Book of the Dead, Rig Veda or Zend Avesta
11:28 AM
Q: Guys please help me solving this problems my lecturer is bad

Abdallah Alsharief Our lecturer is bad because he didn't give us anything from this !

This question is so funny!
@FakeMod it doesn't show research effort.
@Student404Mus Yes, that's why go flag and downvote it....
If you're free
11:59 AM
@FakeMod It's just a desperate student. What's so funny about it?
12:12 PM
@ACuriousMind I know, but the wording of a question gave ma a genuine laugh. There's nothing funny about the OP's situation or the OP, but the way this question is framed is, IMO, funny.
12:31 PM
Should I use $\epsilon$ or $\varepsilon$ for permittivity?
$\varepsilon$ is the standard one
@Slereah Oh! Thanks!
Hm yes, ISO/IEC 80000-6 uses $\varepsilon$.
1:16 PM
Pretty good paper on Wilson loops done rigorously
1:48 PM
2:00 PM
They say, "If the electric charges can move only with
accelerated motions in the self maintaining electromagnetic field, once upon a time they would reach the velocity of the electromagnetic field. The resolution of this problem is the spinning
particle, constantly accelerating and not reaching the velocity of light because the acceleration is radial."
What's the role of spin in preventing the velocity of a charge from reaching the speed of light?
@Student404Mus Who are "they", and what is this "self-maintaining electromagnetic field"? You need to give a bit more context here
That's not a mainstream physics source
"the electric potential difference is self maintained by the
accelerating electrons in the electric current"
2:08 PM
In fact, Raina is somewhat infamous. Don't read that and expect it to make any sense in terms of standard physics
This is interesting!
How is that?
In general, don't trust random articles you find on the internet unless you know that the author is a trustworthy source
Wow! Even in physics the trustfulness is involved?!
I mean in other fields such as history and religion this is common
Hi everyone.
2:11 PM
In particular, the main source for physics articles are either journals or the arXiv. Even on the arXiv you have to be careful (plenty of questionable content there too), but other sources usually are much worse
@Student404Mus ...what did you think the peer-review process is for?
I get all my facts from vixra
@ACuriousMind for what you just mentioned. For trustfulness.
then I don't understand why you're surprised that a random non-peer-reviewed article on the internet is not mainstream physics :P
In what way are arxiv and vixra different?
2:15 PM
Barrier for entry
So many daons
Ok. How to know articles in arXiv are peer-reviewed?
They are not.
@FakeMod viXra was founded by people who thought the arXiv was being too restrictive in the content it allowed
arXiv isn't supposed to be a publication site
It's a pre-publication archive
People just use it because it's much easier and free
@Student404Mus they're not - they're preprints. Papers that have been later peer-reviewed and published will have a reference to the publication (e.g. DOI number)
2:17 PM
@ACuriousMind So arxiv is to vixra, like PSE is to PO?
@ACuriousMind and I think the same applies to Academia?!
@FakeMod what is PO?
@FakeMod similar history, but no. ViXra is full of non-mainstream stuff, PO - for all its faults - is about mainstream physics
Physics Overflow
we should do a stack exchange for non-mainstream physics
@ACuriousMind Hmmm. BTW I am not qualified enough to understand what's mainstream and what isn't :)
@Slereah LET'S RAID AREA 51 ( I mean the site)!
2:19 PM
@Slereah I'm sure you can find plenty of dead proposals for that on area 51 :P
@Slereah what the document above is about?
I mean, is it a non-mainstream doc?
StackExchange network is too mainstream, let's try somewhere else....
@Student404Mus do you expect Daons to be real?
According to what?
@ACuriousMind or go to worldbuilding.stackexchange.com
@Student404Mus If you honestly can't tell, just stick to well-established textbooks
It's not a good idea to be reading articles when you can't even tell obvious non-sense from actual physics
2:23 PM
@ACuriousMind I didn't understand. What I can't tell?
@ACuriousMind It is me who can't tell
@Student404Mus "If you can't tell" = "If you are unable to see on your own that "the Daon theory" Slereah just posted is non-mainstream"
You mean I didn't understand what like these authors are directing to?
@ACuriousMind I didn't read about it before
So I can't tell
@ACuriousMind did you expect from non-mainstream physics to be false or at least speculations?
I don't know what you're saying, sorry.
2:32 PM
non-mainstream = freestyle , right?
@FakeMod All these RAL 4005 profile pictures look the same to me.
@Loong I am happy, because blue is close to my favorite colours, like it's the average of them : cyan and purple/violet
@ACuriousMind I'm trying to find an understanding to the conflict of mainstream and non-mainstream.
@Student404Mus "mainstream" is what is accepted to be true by the majority of actual physicists. "non-mainstream" is what is not.
or why their theories are unacceptable?
Because, at last they are all theories!
2:51 PM
Today a magazine had a column.
Where it ask why Einstein is compared as the most amazing brain of the world?
There were many revolutionizing discoveries instead of relativity.
like maxwell theory of electro magnetism.
Why theory of general relativity is so special?
Does this theory is so unique to be praised like no other theory?
@JohnRennie hi.
Good evening sir.
@YuvrajSingh... It was arguably the first such discovery in the 20th century, when media began to span the globe. It was the right time to get famous.
How today's world look to it? @ACuriousMind
@YuvrajSingh... hi :-)
@YuvrajSingh... I don't understand the question.
@ACuriousMind do you believe that this theory is most unique theory till now?
2:59 PM
@YuvrajSingh... do you mean does it look as impressive today, now that we know so muh more?
@YuvrajSingh... no idea what that's supposed to mean, either, sorry
@JohnRennie correct! Thanks for describing my question!
If so, then yes it does. The theory has proved to be much richer than even Einstein could have hoped.
Oh, a space time fabric concept sir!
@ACuriousMind I have edited the question!
@JohnRennie Einstein can be proved wrong, I have read some physicists article where they said general relativity can be prove wrong!
@YuvrajSingh... I don't know what it means for a theory to be "most unique"
3:06 PM
@YuvrajSingh... It fits with experiment up to a certain level.
@YuvrajSingh... Everyone can potentially be proved wrong. That's just the nature of science.
@YuvrajSingh... Hey! @Student404Mus this is called non mainstream.
We don't believe in GR because Einstein was so amazing (and it has evolved considerably since his time), we believe it because it matches our observations
all the theories are valid within a certain range
@ACuriousMind No. If you are right, how can you be proven wrong.
3:07 PM
Observation's? Like?
@FakeMod And how would you ever, beyond a shadow of doubt, know someone is "right"?
@ACuriousMind When your proposal is a universal truth...
I don't know what that means.
@ACuriousMind For example, there are two types of charges +ve and -ve. How can you refute this?
3:11 PM
There are three types of colour charge and only one type of gravitational charge!
@ACuriousMind sorry, what kind of observation does earlier physicists have?
@FakeMod It is you who has to supply evidence for your claim, not me who has to refute it.
@FakeMod Please, do yourself a favour and never write +ve or -ve again.
@ACuriousMind ahhh! It always ends like this :)
@Loong Sure! .....but why?
@Loong Dammit, I was setting up a line about "I certainly don't know anything about plusve and minusve charges" ;P
3:13 PM
@ACuriousMind It's plusve and hyphenve.
A quick test for the otherwise unoccupied (no Googling!): how many Higgs bosons has the LHC produced so far. To the nearest order of magnitude.
@JohnRennie probably 10^23
Any other takers?
It seems a remarkably small number.
But did they produce enough antimatter to blow up the Vatican?
3:20 PM
In the future, instead of hanging criminals, we should drown them in a sea of antimatter and use the energy released for some other productive purposes...
What does it mean by "the Daon" literally?
@Slereah Look what you did
I didn't find the right meaning
according to my translation it is Devil.
Does this make sense?
@FakeMod I'd prefer we'd not kill people at all.
3:25 PM
@ACuriousMind What to do with people who disrupt everybody else? The ones who are dangerous to be left alone, the ones who should be punished and should bear the brunt of their crimes, what about them?
@Loong I am upvoting that! :P
I don't think so.
@FakeMod And who gets to decide that? I don't want the state to have the authority to kill anyone, "criminal" or not.
Also, "should be punished" implies a retributive theory of justice that is probably far less universally accepted than you think
In any case, I don't want to make this into a lengthy discussion of the death penalty, just letting you know I didn't find that remark funny at all.
And relax ......
Is there any book or paper that criticizes fake physical theories? So one may learn how to not be fooled by any sort of that.
3:38 PM
@Student404Mus use these criteria
@JohnRennie Are you serious?
Baez's crackpot index was meant as a joke originally, but it is startingly accurate!
this turns to be true if we apply it on mainstream and non-mainstream physics, i.e., applying swap operation.
@ACuriousMind No problem! None of my statements are expected to be funny for anyone except me.
3:58 PM
@ACuriousMind for example, one of the assumptions of the Daon theory is, "The photon has energy so it must contain something, i.e. it must have a mass." Does this make it crackpot?
@Student404Mus yes
I'm excited :D
4:09 PM
@Student404Mus to be fair photons can add or remove mass from bound states, so there is a sense in which a photon can be said to contribute to the mass. However a free photon has a zero mass and it's very obvious that it has a zero mass to anyone who has stopped to think about it.
If it didn't have a zero rest mass the electrostatic force wouldn't be an inverse square law. It would also break a symmetry of the EM force called gauge invariance.
4:25 PM
Of note
That's how you know if a mouse is about to con you
Phew! Finally wrote an answer that I am satisfied of.....
I suppose, or rather claim, that I am not at all advertising my answer...... It's just the satisfaction and the contentment that made me make that comment :)
@FakeMod It's a good answer. +1 from me :)
I saw it before seeing your message here btw
@AaronStevens Thanks! The satisfaction is immense....
4:38 PM
Goodmorning/afternoon/night for everyone!

Well, is there in GR literature a Vaidya traversable wormhole solution?
That would just be a wormhole in AdS space
for which there is literature, yes
Oh wait, Vaidya is just time varying
So yes, that's just the general Morris-Thorne metric
4:57 PM
@ACuriousMind you ought to know about Johan Liebert!
> There’s nothing special about being born. Not a thing. Most of the universe is just death, nothing more. In this universe of ours, the birth of a new life on some corner of our planet is nothing but a tiny, insignificant flash. Death is a normal thing. So why live?
@JohanLiebert I like that guy, but he's just too dark and evil....
5:15 PM
@FakeMod he is the death himself. He does not discriminate.
Except for Kenzo Tenma and his sister Anna.
how credible thought experiments are?
@Student404Mus Example?
@Student404Mus Depends on how "correctly" the thinker thinks.
I mean in general point of view in physics
@Student404Mus For example?
5:22 PM
Ths page ☝️ is neither using MathJax nor images, how does it get that kind of math in browsers?
Is it possible for strong thinker to convince you using spoofs?
Also it loads faster that MathJax and looks similar to MathJax.
@Student404Mus Yes
In fact, quite easily
even real experiments use tricks, right?
Can this(👇) be called official but unsolicited medical advice?
Could they lead to fake experiments, if they want to overcome a conspiracy?
5:28 PM
@Student404Mus Not as long as you are smarter than them.
How to be smarter if you are not an expert?
@Student404Mus Smartness and expertise are not really related. Smartness pertains to logic and expertise does to experience and knowledge.
@JohanLiebert What else do you expect from him? :)
you need data to explain.
and data belongs to them.
@FakeMod This is a a big deal.
@Student404Mus Hmmm..... Try to usetheir conclusions to predict something yourself. If the prediction matches with your experience then their conclusions may be correct or else they may be wrong. However in this way, we might end up concluding the QM is a hoax, which it isn't, at least not yet.
@JohanLiebert BTW be ready, Chloroquine is there in class 12th syllabus :P
5:36 PM
@JohanLiebert Just continue to listen to medical experts
@AaronStevens The fact that Trump has asked Modi to deliver(?)/export some chloroquinine yesterday, is now being over-empgasised by our media. Making it seem like it has been clinically tested and is approved for treatment. We will see (in a day or two) a surge in procurement of this medicine by generals (at least that might be the case of India.)
@AaronStevens Wait for the day when Trump calls himself a medical expert. I see it coming.
@JohanLiebert Did you light up diyas?
@JohanLiebert You can choose to listen to medical experts and think that Trump is doing / saying incorrect things
@FakeMod yes we did (though candles). But I believe the whole thing was just done for promotion.
@JohanLiebert For motivation. Whose promotion do you expect to happen when everybody lights up diyas/candles?
@JohanLiebert BTW Are you pro-Modi or anti-Modi?
5:53 PM
@FakeMod I am neutral. Sometimes I support him. Sometimes I am against him.
@JohanLiebert Good! I am somewhere between pro and neutral.
Well I I think that everyone should be somewhat neutral. Support the government when it does good thing and oppose it when it does bad.
@JohanLiebert That's correct! But we are humans and thus we are subjective about good and bad
@FakeMod Yeah! We can't milk a spherical cow, can we? 😂
@JohanLiebert No! Neither can we stop physicists from taking such assumptions..
:53997011 Yup I have seen this before. It's a really good quality GIF
6:06 PM
@FakeMod have you listened this song?
Nope! Might listen it tomorrow...
> TWINKLE, twinkle, little star,
How I wonder what you are!
Up above the world so high,
Like a diamond in the sky.

When the blazing sun is gone,
When he nothing shines upon,
Then you show your little light,
Twinkle, twinkle, all the night.

Then the trav’ller in the dark,
Thanks you for your tiny spark,
He could not see which way to go,
If you did not twinkle so.

In the dark blue sky you keep,
And often thro’ my curtains peep,
For you never shut your eye,
Till the sun is in the sky.

‘Tis your bright and tiny spark,
I mean if pressure acts in all directions then this will make water molecules static then there will be no weight and also I am still confused I still hadn't got it can you please explain it for me again — eman ahmed 3 mins ago
I used to think that it ends after "like a diamond in the sky"!
Can anybody explain me what the OP is trying to say?
6:22 PM
Original version of "baa baa black sheep":
> Bah, Bah, a black Sheep,
Have you any wool?
Yes old mate i have
Three bags full,
Two for my master,
One for my dame,
None for the little boy
That cries in the lane.
@FakeMod I can't follow it
But I haven't look at the rest of the post or your answer :P
@AaronStevens you can click on the "3 mins" to reach his post.
@JohanLiebert I know
Oh! OK.
I am currently doing some online tutoring, so I don't want to read a whole post right now :)
6:36 PM
@AaronStevens Thanks for the confirmation! I was wondering whether it is only me who isn't able to understand that comment. Let me ask the OP to clarify (for the second time).
@AaronStevens Physics tutoring?
I started to hear a sound from 210. And this ended at 12,000. Oh no!. What does this suggest?
6:49 PM
Anybody use Kivy in python? I'm getting annoyed with low-quality documentation and could use some help doing something that should be pretty basic but doesn't seem to be
7:00 PM
@JohanLiebert That you have a bad headset most likely
7:16 PM
@tpg2114 nope sorry
7:54 PM
At a certain point the frequency matched my tinnitus and my ears failed me
8:09 PM
@FakeMod Yeah. Physics and various math subjects
8:52 PM
Somebody on my team just asked if they can get reimbursed for noise-cancelling headphones that cost $1000 that they bought because their workstation was too loud while working at home during the shelter-in-place...
For the younger folks out there -- that's a good example of how to annoy a manager during a tough time ;)
9:14 PM
@tpg2114 were you ill?
Ill? No -- but really out of shape and heavier than last time I rode my bike, which is way way heavier than when I raced all the time
Like... 25 kg heavier than when I was racing
still, losing one pound per month for five years doesn't sound "natural"
Oh, well -- I've gained > 1 lb/year since I stopped riding. Which isn't healthy probably. But, when I did race all the time, I'd start the season around 73kg and I'd end the season around 55kg. Mostly because I couldn't afford to eat enough food for the calories expended
I used to show up to workouts with a 12 pack of Dr. Pepper (1800 kcal) and a 1 pound bag of Mounds bar minis (~2200 kcal) and finish it all during the workout. And still lose weight
Plus all the other stuff I'd consume in a day
No protein shakes?
I used to make a soy protein shake in the morning (chocolate flavored) and add peanut butter, banana, and a whole avocado
I was riding between 70 and 150 miles every day, and 3 times per week, it was like 130 miles where the middle 50 miles of them were racing/interval workouts on the velodrome
There's just a ton of energy expended and not enough money from grad student stipends to buy enough food
9:25 PM
I see.
9:58 PM
@JohnRennie That's physics-level of "question everything" :P
user image
Wanna a meta?
Existence: *exists*
Philosophers: ^
does it make your "spider sense" tingle?
according to wiki intuition=spider sense
10:13 PM
u don't?

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