The h Bar

John Rennie

17:01

We're More Aggressively Enforcing Self-Moderation In Chat

11

Speaking of dubious behaviour in chat rooms

Slereah

"Unfortunately, I need to take a moment and talk about the remaining 3%."

ruh-roh

I think he means us

vzn

@bolbteppa lol yeah call it a sea and then insist that fluid mechanics has nothing to do with it... whatever

John Rennie

@Slereah I think we're pretty well behaved as a whole

John Doe

@Mithrandir24601 Hey do you maybe know anything about Dicke States?

bolbteppa

@vzn call it the Dirac bubble wrap, now no Navier-Stokes is needed

Slereah

17:10

@JohnDoe @JohnRennie just said to not swear!

vzn

@bolbteppa lol, geez fluids have bubbles too... & ps eagerly awaiting your next talk about the Dirac Bubble Wrap :P

Semiclassical

Dirac bucket :P

oh, better: Dirac quicksand

more seriously, the phrase 'Dirac sea' really is a bit of a poor choice insofar as a sea suggests a fluid

Slereah

Cranks love to latch on analogies

Semiclassical

whereas in the Dirac sea the 'space' of filled states is an abstract one

it's not a mechanical fluid.

it'd be like someone taking a reference to the Fermi surface as a literal surface in real space

it's not. it's a surface in momentum space

vzn

@Semiclassical maybe you guys might like to look into the original etymology instead of dismissing it.

bolbteppa

17:20

@vzn It's like a fluid which doesn't move and doesn't do anything and doesn't behave like a fluid at all when it matters, e.g. electrostatic interaction between electrons and positrons, it's like saying electromagnetism is all just Navier Stokes because the field acts like a fluid filling space

Slereah

Etymologies aren't a good basis for physical theories

Semiclassical

^

bolbteppa

Electrosea

John Rennie

A Fermi liquid?

vzn

@bolbteppa the widespread fluid aspects/ phenomena are downplayed/ dismissed in the current paradigm because they "dont fit".

bolbteppa

17:21

Magnetosea, I for some reason don't hear about Navier-Maxwell as the basis of all life

Slereah

well yes

That's a very good reason to dismiss them

bolbteppa

ahah

Slereah

The whole idea of doing QM as a fluid kinda dropped out in like the 30's

Semiclassical

@Slereah it fell out of fashion around then, at least

vzn

@Slereah not if they are widespread. its the equivalent of putting ones head in the sand. or outside the fluid. or whatever.

bolbteppa

17:22

That's elitist

Slereah

I don't think the fluid explanation would really help much with the Bell inequality

Semiclassical

an interesting observation. Wikipedia states the following: "he Dirac sea is a theoretical model of the vacuum as an infinite sea of particles with negative energy. It was first postulated by the British physicist Paul Dirac in 1930[1] to explain the anomalous negative-energy quantum states predicted by the Dirac equation for relativistic electrons"

bolbteppa

I mean really, you could use this thinking to say Maxwell's equations are wrong we should be using fluid mechanics for everything

vzn

@bolbteppa lol right! science is created by humans, and humans tend to be elitist. (in worst cases...)

Semiclassical

But if you go to the original 1930 paper, I don't find the word 'sea' at all in there

Slereah

17:23

@Semiclassical Probably earned the nickname later on

Like the big bang theory

vzn

@bolbteppa maxwell used fluid analogies to come up with his eqns. how many textbooks point that out? o_O

Slereah

@vzn They stopped ever since the ether was dropped

You lunatic

Emilio Pisanty

@dmckee I seem to recall you were interested in this template - so here's a heads-up that it's now online ;-).

Slereah

Jesus

Semiclassical

@vzn not a lot, but not many people actually read up on the history of E&M in any depth

Slereah

17:24

Talk about an obsession

Semiclassical

for the simple reason that the history is separate from the physics

(not completely separate, perhaps, but they're pursuing different questions)

Slereah

not everything has to be a fluid

vzn

@Slereah lol figured someone would call me that sooner or later. am happy to report, took a nice moonbath last nite. had some nice new zoom binoculars and was looking at it in detail. awesome! :)

Emilio Pisanty

@vzn what are 'zoom' binoculars and how do they differ from regular binoculars?

vzn

@Slereah would you say einstein was "obsessed" with the properties of space?

Emilio Pisanty

17:26

or rather, what are non-zoom binoculars?

Slereah

@vzn Yes, actually

Einstein was really dead set against singularities

vzn

@Slereah lol then am in good company :P

Slereah

And was convinced that GR was free of them

he was proven fairly wrong

Semiclassical

The thing I"ll point out with regard to why I don't see the 'Dirac sea' terminology as suggesting a fluid interpretation

bolbteppa

In the spirit of arguing by analogy: Maxwell might have argued using fluids to motivate what he did, but Maxwell theory does not satisfy the equations fluids satisfy, similarly the Dirac sea might be analogy, but applying fluids equations to it is to completely miss the point

Semiclassical

17:27

is that it's mathematically no different than the notion of a free electron gas whose states are filled up to the fermi energy

And I can tell you, from knowledge of how quantum mechanics works in such systems, that there's nothing 'hydrodynamic' about that setup

vzn

@Semiclassical gases are quite interrelated with fluids.

bolbteppa

Maybe vixra has Water-Maxwell unification though :p

Semiclassical

Matter-Waxwell

@vzn not in this respect. The filling of states occurs in momentum space, not in real space.

Emilio Pisanty

@Semiclassical yeah, that definitely just rolls of the tongue, doesn't it?

bolbteppa

'Here we use the Evans sprinkler function'

vzn

17:29

@Semiclassical there are strong similarities in the math. same with bose einstein condensate etc.

Semiclassical

Not here there isn't, except to the extent to which any QM system can be interpreted hydrodynamically

the 'Dirac sea' is not special in that regard

Emilio Pisanty

@vzn you're explicitly being told that there aren't, by someone who's actually in the field.

Semiclassical

plus, Bose-Einstein condensates are bosonic and therefore can have lots of particles in one place in momentum space

whereas electrons are fermions and therefore can't occupy the same spot in momentum space

Emilio Pisanty

there are indeed mathematical similarities to hydrodynamics in Bose-Einstein condensates in certain conditions, but Fermi gases are very different beasts entirely

vzn

Physics chat where ~~new~~ old ideas go to die™

Semiclassical

17:33

If they're not worth surviving, then I don't see why that's a bad thing

John Rennie

@vzn any fool can come up with new ideas

Semiclassical

My main beef here is that one needs to have the math to appreciate the differences between these things

vzn

not all scrap heap/ dead ideas were executed with (perfect? infallible?) justice one might say...

ACuriousMind

@Slereah I would like to think that he does not. If you think he does, then that would suggest something needs to change around here.

Semiclassical

Just because something has a hydrodynamic interpretation doesn't mean you gain any insight by thinking this way. It may give you insight, but to assume it does is to put the cart before the horse.

bolbteppa

17:35

If anything, you would treat the Dirac sea using Maxwell theory rather than fluid theory, http://hitoshi.berkeley.edu/221B-S01/14.pdf
"The Dirac sea is a collection of infinite number of electrons in negative energy states. Even though it has an infinite (negative) charge, as long as it is completely homogeneous, we will not be able to detect it because there is no preferred direction to produce an electric field. However, if the homogenity is broken, for example by the presence of a point charge, the distribution of the negative energy electrons is no longer homogeneous and can have a phy…

ACuriousMind

@Semiclassical I'm sure there's a hydrodynamic interpretation for the beer running into my gullet, but it's definitely not an enlightening one ;)

Slereah

I do hope your beer is a liquid

Semiclassical

lol

ACuriousMind

@Slereah Mostly, yes

vzn

← aieee, heavily outnumbered

Semiclassical

17:36

You're in the Physics chat.

Surrounded by people who largely know what they're talking about.

ACuriousMind

Although e.g. unfiltered Hefeweizen still has yeast bits in it

Slereah

not me

No idea what I'm talking about

bolbteppa

How would this have gone if we were talking about Faddeev-Popov ghosts :p

Slereah

He would have come up with a QM theory of ghosts

why do you think they call it the SPECTRAL THEOREM

Semiclassical

@bolbteppa quantum hauntology

ACuriousMind

17:38

@Slereah lol

Semiclassical

(i have no idea what hauntology really is, but it's a good word)

ACuriousMind

Oh dear, that's a real word

bolbteppa

cohauntology is a bit off though

Semiclassical

yeah

ACuriousMind

coined by Derrida, no wonder you don't know what it really is :P

Semiclassical

17:39

lolyes

ACuriousMind

hauntology is where you chase the ghosts, cohauntology is where the ghosts chase you

Slereah

Post modernist swine!

Semiclassical

'quantum hauntology' seems like a pretty good synonym for how interpretation seems to work at times

bolbteppa

Projective quantum cohauntology of BEST ghosts

Semiclassical

"Who ya gonna call? Ghost-BRSTers!"

ACuriousMind

17:41

@bolbteppa Good candidate for arXiv vs snarXiv

bolbteppa

Tree hauntology of forests is also a potentially real hep.th one surprisingly

ACuriousMind

Possibly tree-level hauntology?

'"This house is ghost-free to second order"

vzn

> The term refers to the situation of temporal, historical, and ontological disjunction in which the apparent presence of being is replaced by a deferred non-origin, represented by "the figure of the ghost as that which is neither present, nor absent, neither dead nor alive." wikipedia

↑ traces of schroedingers cat o_O

@JohnRennie but not all new ideas are foolish... it might be "foolish" to think so... :|

Slereah

Well yes, but then you have to show it

Especially if they're just recycled old ideas

bolbteppa

For some reason it's really only all those ivory tower stuffy establishment types are the ones coming up with all the valid new ideas, almost like one needs to know the theory they are talking about properly

Slereah

17:52

True, it's never a hobo

you never see a paper authored by Skidrow Jim

vzn

the ideas are all lying around, disconnected, almost all of them already written down somewhere, waiting to pounce, they havent gained enough "strength/ unity/ momentum" yet, but its building o_O

bolbteppa

The sheer amount of time needed to even learn this stuff, let alone go beyond it, will exclude most attempts quick enough

vzn

@Slereah you missed the fun in here yesterday

Slereah

also starting from the point "QM must be wrong" doesn't usually give great results :p

Oh no I didn't.

I do my best to stay out of such discussions

I can see where it's headed

vzn

23 hours ago, by Chakrapani N Rao

http://vixra.org/abs/1804.0317

↑ EP defended it so it must be good :P

bolbteppa

17:59

Is that serious

Slereah

well it's a vixra paper

Semiclassical

he protested against rejecting it on the basis of it having no citations after a week

enumaris

grrrr....the IT department pushed out an update over the weekend...now my progress is lost -.-

Semiclassical

which I think is pretty fair.

(rejecting it on the basis of it being on vixra, by contrast, seems like a reasonable heuristic)

bolbteppa

It's 6 minutes off 42, clearly something's fishy

Slereah

18:00

Can I reject it on the basis that it's not in TeX?

enumaris

always

Semiclassical

lol

Slereah

also it's one page long

vzn

@Semiclassical lol EP, defender of the vixra downtrodden

Semiclassical

it is a pretty strong alarm bell

again, his point was that "citation count after a week" is not a good indicator of quality

given a vixra preprint with a lot of citations vs. an arxiv preprint with few citations, I'll still trust the arxiv preprint

vzn

18:02

@Semiclassical ah, right, expert indicators of paper quality? by those who dont even read them?

enumaris

my thesis is full of citations...like nearly 200....most of the citations I didn't read...and had to add for political reasons...

Semiclassical

as a heuristic, yes.

bolbteppa

'if my paper was wrong, all I would need is 1 citation disproving it', I can easily see this being flipped to justify it's correctness :p

enumaris

nowadays, people get offended if u don't cite their paper

Slereah

@enumaris Citing everyone on the jury?

enumaris

18:04

well my thesis was a combination of papers

so it's more like

vzn

@Semiclassical there are a lots of credible arxiv papers on topics that are routinely rejected without consideration in here, maybe need to give up on citing them (unless new ppl show up), it seems mostly futile. :(

Mithrandir24601

@JohnDoe I've heard of Dicke states, but not much else

enumaris

the referee made some veiled comments about how I didn't do a "balanced citation list"...and I had to cite every paper I could find that sorta touched the subject lol

vzn

@enumaris lol EP insists they are are references not citations :P

Semiclassical

@vzn well, it's a relative thing

Mithrandir24601

18:05

@enumaris So... You didn't cite one of their papers?

enumaris

what's the diff?

I'm guessing I missed some of the referee's papers...but since I can't know for certain who the referee is, I just went and more or less did google searches to cite everybody who touched the subject

Semiclassical

just b/c on it's arxiv doesn't mean it's good, no. but it being on vixra is not a good sign

Slereah

I've seen a few kooky arxiv papers

Semiclassical

it being on arxiv doesn't take away from the credibility of the paper. but it being on vixra decidedly does.

enumaris

my original submission had like a pretty extensive citation list already though, like probably 40 citations...

Semiclassical

18:06

you're judged by the company you keep, etc

Slereah

What's the hierarchy?

bolbteppa

There vixra ones vixra.org/author/william_o_straub are good for example

enumaris

but since the referee was b*tching about the citation list...it went up to like 98 by the time it was accepted

Semiclassical

and if you put a paper on vixra, you're in a lot of bad company

Slereah

vixra < ResearchGate < Arxiv < Real journal

Anonymous

18:08

What about Academia

bolbteppa

Putting stuff on there validates these guys though

vzn

@Semiclassical think ppl around here are routinely judging "credibility" on superficial metrics. alas, took me awhile to realize it. "confirmation bias..." whatever

Semiclassical

I'd put 'original research hosted on a blog site' as above vixra. not sure where to put it vs. ResearchGate

Slereah

@Semiclassical Praise Motl

@Blue I'm not sure I've ever actually read a paper from Academia

Semiclassical

@vzn life is short and humans use heuristics.

Slereah

18:09

@vzn Can't read every crazy paper out there!

Got shit to do

enumaris

I've never even heard of vixra and researchgate

loool

Slereah

he said, watching Dragon Ball Z

Semiclassical

I'd put "original research hosted on an academic server" as about parallel to arxiv

Slereah

What about a geocities website in all caps

vzn

@Semiclassical yes, exactly, so therefore am still just waiting for Mr Big Shot Alpha Male to announce to everyone that Fluid Dynamics Is the Thing and then for the whole herd to stampede. Couder/ Bush et al so far are not enough. :(

Semiclassical

18:11

@vzn I'm sorta dubious that that will happen, but it is an interesting question: What would Bush et al need to discover in order to get the attention of the physics community at large?

They're not unknown, to be sure.

Mithrandir24601

@Semiclassical Yeah, I'd say that this is just what Arxiv is, only bigger than any of the others

Semiclassical

But it's not a hot topic

@Mithrandir24601 true

Slereah

He'd probably need to do the bloody EPR experiment

Any crazy scheme in QM usually dies on EPR

Due to the Bell inequality

Semiclassical

I do wonder about the bell inequality, yeah

vzn

@Slereah actually have been thinking along those lines also.

Anonymous

18:13

BTW could someone here explain me what exactly "open sides/edges" and "closed sides/edges" mean in graph theory?

Anonymous

That terminology is soo confusing

Anonymous

Also "open cluster" and "closed cluster"

Semiclassical

I have a hard time believing that they can succeed at replicating violations of the Bell inequality in their setup

vzn

@Semiclassical am both agreeing and disappointed in your sentiment because it seems to show that somehow "mere striking results" are not really enough. but do think a tipping point is nearby/ inevitable at this point, and maybe it will be somewhat random.

Slereah

The Bell inequality basically forbids any classical probability

I doubt a fluid theory could have contextuality

Semiclassical

18:14

Ehhhh

Anonymous

@BalarkaSen Do you happen to be around?

Semiclassical

I'm not sure there. Pilot wave theory definitely survives that test

(it has other problems, of course)

Slereah

@Semiclassical has it

I still haven't seen any dBB version of EPR

Semiclassical

Well, which version of EPR?

The original Einstein one, or the spin version of it?

Slereah

Any that exhibits the Bell inequality

or any of the weird counterfactual experiments, I guess

vzn

18:16

@Slereah saw your arduino experiments, are you still doing anything with electronics? am thinking of doing a homegrown bell experiment soon, posted question on it

Slereah

Not right now, no

Semiclassical

I'm pretty sure it passes those. The trajectories are weird and nonlocal, but to the extent that a wavefunction exists for that system there'll be pilot wave trajectories associated to it

Slereah

Homemade EPR isn't easy to do

Sir Cumference

Morning

Slereah

You need good receptors for one photon experiments

and I think the weird nonlinear crystal stuff for entanglement

Though I'm not big on experimental QM

So I don't know

Semiclassical

18:17

Note that I'm talking only about Bohmian trajectories stuff

not de Broglie's double solution stuff

that's separate and i dunno

Slereah

@Semiclassical The wavefunction isn't the hard part

vzn

@Slereah it has never been done, but that doesnt mean its impossible. have some ideas.

Slereah

Most theories do the wavefunction okay

I think even the old fluid QM did the wavefunction fine

Semiclassical

well, fluid QM is just madelung transformation

@Slereah arxiv.org/pdf/1509.00767.pdf maybe

Slereah

I'll give it a look

Semiclassical

18:21

bigger pictures in this version: mdpi.com/1099-4300/20/2/105/pdf

Blue Bug

urrr.... cry for help, I am told I can switch the email address linked to this account of mine by contacting SE staffs, anyone know how to contact the staffs?

Anonymous

@BlueBug Eh. Just add an alternative login and then delete the existing one, manually.

Semiclassical

@Slereah one part of that abstract which I like is the last line:
"Finally, we discuss the fact that Bohmian mechanics is attractive to philosophers but not so much to physicists and argue that the Bohmian community is responsible for the latter."

Blue Bug

I have too many precious fake internet points stacked onto this account though @Blue

Anonymous

@BlueBug You're not going to lose your points.

Slereah

18:24

The big annoying part about interpretation discussions is that the kind of people who would do them are usually evangelists

John Rennie

@BlueBug he didn't mean use a new account.

Anonymous

Blue Bug

597 6 20

Slereah

Might as well talk about weed or abortion

Semiclassical

lol

I think Gisin does a reasonable job of avoiding that?

Blue Bug

I mean 600 is like not much but I had been here for like almost 5+ years

I collect points at rate of 100 per year

vzn

18:25

Feb 22 '15 at 18:47, by vzn

[a14] "violation of bells inequality in fluid mechanics" anderson/ brady

John Rennie

@BlueBug on your account page click on "Edit profile and settings"

Slereah

@Semiclassical Bohm was probably one of the worst for that :p

John Rennie

The on the left you'll see a link for "My Logins" - click that

Semiclassical

meh

I think there's been some stronger advocates than Bohm

John Rennie

@BlueBug then you can add a login for your new e-mail address to your existing account.

Slereah

18:26

@Semiclassical probably, but few as famous

Semiclassical

can't argue there

Blue Bug

sorry I was unclear with my problem, I have two accoutns with two different emails

this is my main and the other one I created needs to go away, I am told I can "merge" accounts

Anonymous

Okay. Then click on "Contact" on the main page

Slereah

Evangelism never does a cause much good in physics

Blue Bug

stackoverflow.com/…

I Found it ty! @Blue

Slereah

18:29

Nothing turns me off more of a quantum gravity theory than "obviously this is the most logical theory!"

although really, that's all of them

I rarely see a quantum gravity book that starts with "here's a dumb theory I came up with"

bolbteppa

(String theory is the only exception)

Slereah

Obviously you've never read Motl

About how string theory is the best thing since sliced bread

bolbteppa

My point

Slereah

actually

There are theories of gravity that were made just as counterexamples

bolbteppa

I meant, string theory is the only theory which gives a theory of quantum gravity and says it's the most logical, it's the only logical :p

Slereah

18:35

Although those weren't quantum theories

I think they were mostly done to prove that gravity couldn't be a vector theory

bolbteppa

The way I see it, for QFT you have RQM motivating most of the stuff in there, for the standard model you have all that Fermi vector current stuff motivating it, and for strings you have all that dual model qcd stuff motivating it, then it's all natural, and as a by-product you get quantum gravity as your reward

Slereah

every theory of quantum gravity has a motivation

that's how they do them!

bolbteppa

With strings it was the graviton states popping out by accident that led to it I think, which is interesting in that it happened by accident

Slereah

yeah

I mean, you know

I like string theory and all

What I don't like is hubris

Did we learn nothing from Icarus!

enumaris

nothing

0celo7

18:57

calling the IRS

kill me

Slereah

I'll get the gun

just tell them that you're a free man of the land

dmckee

@EmilioPisanty The links in "or you can see and download" 404'ed for me.

bolbteppa

Mwatl do you mean hubris...

0celo7

Saw some llamas

0celo7

19:28

@Slereah I have a riddle for you

I have a VB $E\to M$. What's the name of the bundle over $M\times M\times \Bbb R$ with fibers $E_x\otimes E_y^*$, $x,y\in M$

it's not $E\boxtimes E^*$

Slereah

isn't that the bitensor bundle

Oh

also why $\mathbb R$?

Droleulb

@BlueBug good bug

0celo7

really $(0,\infty)$ but that part isn't important

Slereah

Sounds like the bitensor bundle, but beyond that, I dunno

0celo7

I discovered some applications of my stuff to parabolic equations so I'm writing it up

@Slereah it's not because there's a time variable

Slereah

19:32

Dunno if there's a specific name for that

Although it might be used in like... QM maybe?

Non-relativistic propagator parametrized by time

I dunno

0celo7

it's for a propagator, yes

enumaris

prop prop propagator

dmckee

@Slereah You need to be careful about definitions if you want that to be true. More than a few good ideas are named after the person who went around giving talks and showing that the idea was useful rather than the original inventor.

Slereah

@dmckee I guess the bad part is when you go on about the sins of the other theories!

dmckee

Publicity is sometime necessary and often useful, it's just that there is a kind of publicity that turns people off.

Slereah

19:37

Especially ones that work

0celo7

oh my goooooooooooood is westworld out?????

Semiclassical

19:56

a quote from Copernicus, regarding prior models of the planets and sun

"Moreover, they have not been able to discover or to infer the chief point of all, i.e.
the form of the world and the certain commensurability of its parts. But they
are in exactly the same fix as someone taking from different places hands, feet,
head, and the other limbs - shaped very beautifully but not with reference to one
body and without correspondence to one another - so that such parts made up
a monster rather than a man"

In what I'll pretend is unrelated news, I think I'm about to send my thesis out to the reviewers on my committee

0celo7

good luck

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