The h Bar

heather

2:01 AM

okay, done

with both commands

wait, what...

i checked the version

DanielSank

and?

heather

and it gave 1.7.9.5

exactly what it gave before

Slereah

Apparently there is a theorem why QFT can't use operator valued functions

Due to Wightman

But that paper doesn't show the proof

It seems to be that if you try that every field operator just sends back the vacuum

DanielSank

@heather :\

Slereah

@ACuriousMind halp

heather

2:06 AM

is there a specific update command i can use on git?

or do i need to say install git 2.whatever?

Bernard Meurer

@heather Hm

What's the output of $lsb_release -a

heather

a bunch of stuff, among it Ubuntu 12.04.5 LTS

Bernard Meurer

Ah, that's why

that's old

DanielSank

hahahaha

oops

lol

Why didn't I think of that?

Bernard Meurer

sudo add-apt-repository ppa:git-core/ppa
sudo apt-get update
sudo apt-get install git

user228700

2:09 AM

Does anybody know any physical chemistry? I have a quick question about the dew point and exactly what it means :-|

Bernard Meurer

@heather That

You need a special repo to get the latest git releases since you have old Ubuntu repos

heather

okay

ACuriousMind

@Slereah What do you need

DanielSank

@BernardMeurer I guess that's one way to do it.

heather

umm... add-apt-repository: command not found

DanielSank

2:10 AM

Would upgrading her distribution be a bad idea?

Bernard Meurer

@DanielSank Idk, I don't want to do anything risky

heather

and i made sure to use sudo

DanielSank

@BernardMeurer okey dokey

It's just easy to forget what ppa's you've added.

No big deal.

heather

do i need to go into the main directory instead of the /calculus-notes one, or...?

Bernard Meurer

@heather Did that work?

heather

2:16 AM

going into the main directory @BernardMeurer? no, command not found again =/

Bernard Meurer

@heather You sure you're writing it correctly?

This really should work

sudo apt-get install python-software-properties

You need this package

then you can do add-apt-repository

heather

okay, I'm installing the package

okay, now the add-apt-repository worked

ACuriousMind

@BernardMeurer Never feel bad for interrupting someone trying to teach people wrong things. These people are a plight, they are only able to spread misinformation precisely because no one ever stands up and calls them out on it.

heather

okay, update done

installing git...

DanielSank

@ACuriousMind Yes, but be nice about it.

Embarrassing someone in public is almost always a very bad idea.

heather

2:21 AM

git installed, did git --version

and it gave 2.10.2

woopie!

::fist-pump::

lol

:)

@ACuriousMind That's what I thought

Slereah

@ACuriousMind Do you happen to know where I can find Wightman's proof of functions not working for QFT

Bernard Meurer

2:22 AM

@ACuriousMind I'll talk about this more tomorrow

I gotta go folks

Slereah

Also this paper doesn't include the CCR as an axiom, is it unnecessary

ACuriousMind

@DanielSank If that someone holds some sort of power over you, yes. Otherwise, it is sometimes necessary. Sure, don't be mean for the sake of being mean or appearing superior, but also don't concede points simply because it would embarrass the other party showing they're wrong/baseless.

heather

@BernardMeurer, have a good night! =) thanks for your help!

ACuriousMind

@Slereah Not in those words. What exactly do you want to show?

DanielSank

@ACuriousMind There are ways to add new information without making the other person's wrongness the focus.

This is a very important skill.

"Oh, I've studied that a bit. I have some information to add."

You can directly contradict what the first person said without ever saying "what you said is wrong".

From a scientific point of view, note that the fact that the first person was wrong is irrelevant.

Pointing it out serves no purpose.

heather

2:25 AM

@DanielSank, okay, I cd'd into the /calculus-notes directory

DanielSank

@heather k...?

heather

@DanielSank, oh, I just was going to see if push didn't work now on the second branch

ACuriousMind

@DanielSank But why should you? If they're wrong, they're wrong. It's not relevant that the person was wrong, but it's important that you are not "adding information" but correcting what was said. "That's wrong" takes a lot of confidence to say, but if you are confident it is true, you should not dance around that fact.

Slereah

@ACuriousMind Apparently the theorem is something like, if you use operator valued functions as a basis for Wightman's axioms, you get something along the like of $\hat \Phi (x) |\psi\rangle = c|\Omega \rangle$

For some constant $c$

heather

whoa, now I've got a new problem

what is it with me and these weird problems?

ACuriousMind

2:28 AM

"From a scientific point of view", there's no shame in being wrong. Scientists are wrong all the time. The important thing is that we own up to our mistakes.

heather

::sighs::

it says that it can't find any of my tex files in any of the branches when I try to add them

dunno what's going on there

i'm going to take a break from this for a little bit and come back to it

i think I'm about to go find Tux and smack him =P

ACuriousMind

@Slereah You mean you replace the statement "fields are operator-valued distributions" by "fields are operator-valued functions" and then that's the result?

Slereah

It seems to be related to the Poincaré invariance of the vacuum

Apparently that is the claim, yes

ACuriousMind

Well, how is the CCR supposed to look like if they're not distributions?

DanielSank

@ACuriousMind Unfortunately, human feelings etc. matter quite a lot in the pursuit of education and science at large.

Slereah

2:30 AM

The axioms do not include the CCR, strangely enough

At least not in this paper

ACuriousMind

You can't write $[\phi(x),\pi(y)] = \delta(x -y)$ if $\phi,\pi$ are not distributions.

DanielSank

@ACuriousMind I can't tell why you're arguing this point.

Yes, we should all detach our emotions from science. You know damn well this is not how the world actually works.

Slereah

I checked Glimm and Jaffe and they are also not on the list of Wightman axioms

ACuriousMind

@Slereah Sure they aren't because the Wightman axioms don't really know about a Lagrangian or $\pi$.

DanielSank

@heather I might know why that happened and how to fix it. Not sure though. Can help later.

Slereah

2:33 AM

But they have both field operators and momentum operators

Can you derive the CCR from Wightman or do you have to include them in specific theories?

Can you have a non-CCR/CAR theory of QFT

Also non-CAnyonR theory I guess, for 2D

ACuriousMind

@Slereah I don't see where the Wightman axioms include a momentum operator.

Slereah

The unitary representation of the Poincaré group

ACuriousMind

@Slereah That's not the conjugate momentum!

Slereah

What is it then!

ACuriousMind

It's just the total four-momentum

The conjugate momentum and its CCR with the quantum field depend on the Lagrangian, which the WA make no mention of.

Slereah

2:36 AM

But then is it mandatory or not for a quantum theory?

ACuriousMind

And there are QFTs without Lagrangian descriptions, and therefore without a conjugate momentum. I think I remember some variants of Seiberg-Witten theory only have "local Lagrangians", but I don't recall any details

Slereah

Hm

ACuriousMind

@DanielSank I'm fully aware that it might hurt someone's feeling if I tell them they're wrong. That is, however, preferable to giving the impression that their notions and arguments have merit to them when they don't.

DanielSank

@ACuriousMind Yes, the preference you indicated is correct.

ACuriousMind

In any case, I've not heard about that theorem of Wightman you're talking about, @Slereah, sorry

Slereah

2:38 AM

That paper doesn't mention a bibliographical ref for it

Quite rude

DanielSank

There is a sort of "correctness > people" idea in software and physics, and frankly it leads to a lot of would-be interested people leaving before they have a chance to learn what it's all about.

Slereah

The bibliography only mentions one book by Wightman

Guess I'll check that one

"PCT, Spin and statistics, and all that"

The full theorem, btw :

DanielSank

Yes, correctness is prime, but people let this justify unnecessarily confrontational tone so often that I think it's worth remembering that there are different ways of correcting misinformation.

Slereah

"Let $\Phi$ be a field in a Wightman QFT which can be realized as a map $\Phi : M \to \mathcal O$ and where $\Phi^*$ belongs to the fields. Moreover, assume that $\Omega$ is the only translation-invariant vector (up to scalars). Then $\Phi(x) = c \Omega$ is the constant operator for a suitable constant $c \in \Bbb C$"

I wonder if that spells bad news for my QFT with hyperreal idea

If the CCR are not why it doesn't work it doesn't bode well

dmckee

@Kaumudi John R hs gone to bed, but he might know. I ought to know but fear that I don't

ACuriousMind

2:45 AM

@DanielSank Well, "correctness > people" is an integral part of the scientific method. I think what you're complaining about is that many people in our fields are rather bad at bringing across that this doesn't mean people are devoid of value, and that it also doesn't mean it's a personal failure to be wrong. That is, however, totally different from not saying the other person was wrong, in my view.

Slereah

Are you sure he is not devoid of value, though

user228700

@dmckee I'll wait for him to wake, thanks :-)

Slereah

Also who are we talking about

I have gotten стреатер р.ф., шигхтман а.с. пцт, спин анд статистицс анд алл тхат

Good old шигхтман

And his шигхтман axioms

"The idea of this book arose in a conversation with H.A. Bether, who remarked that a little book about modern field theory which contained only memorable results would be a good thing."

None of those boring results

This is a book 100% about great things

ACuriousMind

@Slereah Is there a $\Omega$ missing after your $\Phi(x)$ there? Then it would seem the intent is to show that in this case, $\Phi(x)\Omega$ is translation invariant for all $x$ and so has to be a multiple of $\Omega$.

Slereah

There is not

The notation is a bit confusing but I think it's meant to say "It only produces the vacuum"

ACuriousMind

2:51 AM

$\Phi(x) = c\Omega$ doesn't make any sense, though

Slereah

Yeah

ACuriousMind

The l.h.s. is an operator, the r.h.s. a state

Slereah

Partly why I want to see what Wightman says

ACuriousMind

I'm afraid I really have never heard of such a theorem, my best motivation for why fields must be distributions is that we want their canonical commutator to be a distribution.

Slereah

This seems like a pretty good book btw

Basically it's a QFT book with none of the thrills

Why do so many physics book like to sprinkle lewis carroll quotes

DanielSank

3:02 AM

@ACuriousMind I think it is wholly unnecessary to say that a person is wrong.

It is sufficient and more productive to focus entirely on the statements that are wrong.

That may sound trivial, but my goodness to people screw this up all the time.

Slereah

Apparently $\hat \varphi(x) = \hat 1$ satisfies all axioms

A fine QFT

ACuriousMind

Sure, don't get up in their face and say "You're wrong!" but say "That's wrong.". And yes, that does sound trivial to me :P

DanielSank

@ACuriousMind It's not trivial at all.

ACuriousMind

@Slereah I can'T find the theorem your paper seems to be referring to in Streater/Wightman, though

They just start off with distributions not giving much reason for it

Slereah

Yeah I can't either

It is bothersome

I'd rather not wade through all the Wightman papers

DanielSank

3:05 AM

@ACuriousMind There's a world of difference between "Einstein was wrong about entanglement" and "Turns out that entanglement is real".

ACuriousMind

@DanielSank I see the difference. I'm not sure what we're arguing about at this point. I agree you shouldn't make it about the person. But you should point out wrong statement when you hear them, and there's no point in mincing words about that - if something is wrong, it is wrong. Maybe it's a language issue. In German, the phrases "You're wrong" (Du hast unrecht) and "That's wrong" (Das stimmt nicht/Das ist falsch) are not easily interchangable, so I don't really confuse them.

DanielSank

They are confused in English all the time.

Not sure why

gtg

ACuriousMind

Well, because you use "wrong" in both cases!

For me, a thing being "wrong" and a person being "wrong" are two entirely different concepts with their own words attached.

vzn

@DanielSank agreed! just wanted to say this reminds me of some psychology theory wrt distinction of "criticism vs complaining". am (long) attempting to discern/ delineate this boundary better myself gottman.com/blog/the-four-horsemen-criticism

Slereah

The horror

ACuriousMind

3:15 AM

@vzn I'm afraid I don't see how a blog about resolving issues in a personal relationship is directly relevant to scientific debate. There's a large difference between a clash between two entirely personal viewpoints and disagreeing about something which can be settled by facts.

vzn

@ACuriousMind lol figured someone might question it on exactly those grounds and its certainly a valid point. but on other hand isnt all communication inherently about relationships? anyway have found the distinction of "criticism vs complaining" to be personally helpful, think its close to the distinction DS is making, & am aware gottman is redefining the terms somewhat from a specialist psychology pov. (many psychology terms are like that etc)

ACuriousMind

@vzn The point about the complaining with statements focusing on "I" and not "you" is that complaints about behaviour in a relationship are intrinsically subjective - what behaviour one person expects is not what another expects, and there's no one "correct" way of behaviour. In a scientific debate, there is an ideal truth to be discerned, and "I" statements are simply invalid because our personal feelings about facts are immaterial to their truth.

I'm not questioning the validity of the approach to discussing issues in personal relationships, but I really don't see that it is in any way transferable to discussions about objective facts.

vzn

@ACuriousMind think the distinction of criticism vs complaining has some relevance in scientific contexts in eg avoiding ad hominem style expression(s) something you raised yourself here somewhat recently in another context... seems to me gottman is redefining criticism as something that comments on a persons character aka nearly ad hominem. agreed facts≠feelings as is pointed out/ emphasized in some other psychological literature eg "CBT"...

ACuriousMind

I read the article entirely differently: A "criticism" is something that talks about a feature of the other person (not an ad hominem, it truly names a disliked feature the speaker perceives about the other person which is the problem itself) while a "complaint" is something that focuses on the speaker's personal feelings and opinions induced by the adressed person's actions.

vzn

> ad hominem 1. (of an argument or reaction) directed against a person rather than the position they are maintaining. "vicious ad hominem attacks"

ACuriousMind

3:25 AM

@vzn There is no "position" in the relationship debate posed in the link - the entire discussion is about a specific behaviour of the other person. It's not an ad hominem to fault the other person for that behaviour; it's just unhelpful.

The entire point of an "ad hominem" is that I attack my opponent's character instead of their logical argument. In a debate founded on emotions rather than logic, the concept of an ad hominem doesn't make any sense.

vzn

@ACuriousMind actually my opinion is that gottmans theory is limited somewhat for reasons that you man be getting at :| ... but anyway believe it or not he formulated a lot of his theory based on extensive observational psychology ie scientific research! however it can be subtle at times...

ACuriousMind

I'm not questioning Gottman! I don't know any of their work. But the article as written just doesn't apply to scientific debate because it is written explicitly about disagreements in a personal relationship.

vzn

lol. think if you read his example criticisms carefully, theyre quite similar to ad hominem statements, if not exactly that.

ACuriousMind

If my issue is that my partner didn't call me and I think that it's because they didn't think of me, then saying "I think you did this because you're selfish" is an attack on their character, sure, but it's not an ad hominem because my entire problem is that I feel they are selfish. There are no "ad hominem"s if the discussion is about my partner's characteristics to begin with. An ad hominem would be if I said "You're selfish, so you can't be right about which philosophy is best for all"

An ad hominem requires that there is a part of the discussion which has nothing to do with a person's character, and yet I insist on dragging their character into it to discredit them.

Not all insults are ad hominem, and not every ad hominem is an insult.

vzn

(btw did you take any philosophy classes?) there may be a distinction here or maybe not. having some trouble following the distinction youre making. you seem to consider debates over topics to have special status in communication. but wrt ad hominem defn quoted earlier, virtually all communication involves "positions", maybe even unspoken ones... eg in your example "not calling" could be considered a "position" (albeit unspoken)

ACuriousMind

3:42 AM

@vzn Well, not at university, but philosophy was one of my favourite classes in school. My point is that an "ad hominem" is a particular form of invalid argumentation in a debate based on logical reasoning by its definition. Of course emotional debates about what the participants feel in a relationship have positions, but there are no fallacies (of which ad hominem is one) in such debates because there is no "correct" way of reasoning to begin with.

It's all about subjective feelings, not about objective truth that can be arrived at with logically correct reasoning.

You can't apply the notion of "fallacy" to a debate which does not in principle have a correct outcome.

(That's a large problem in political discussions, by the way. Usually, the participants start from different, unstated premises, which makes their arguments essentially incommensurable)

vzn

"ad hominem" is just an adjective based on its defn. agreed it is often/ typically applied to arguments but dont think thats the only valid context. actually gottman was indeed describing arguments in his own distinctions... actually do think there are fallacies wrt emotions, but its complicated...

DanielSank

4:13 AM

Hi, everybody.

user116211

4:59 AM

@DanielSank o/

DanielSank

5:16 AM

@MAFIA36790 \o

user228700

6:29 AM

@JohnRennie: Morning :-) Are u busy?

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