The h Bar

Mithrandir24601

21:00

(or maybe I'm just too tired today or something)

David Z

→ 8 messages moved to Room for David Z and Bernardo Meurer

Slereah

I do think the GNS procedure is the wiggling around

You start with a state $\omega(A)$, which corresponds to $\langle \Omega, A \Omega \rangle$

The algebra modulo zero norm elements form the Hilbert space

So that basically you have $\langle A, BC \rangle = \omega (A^* BC) = \langle A^* \Omega, B C\Omega \rangle$

Then you work with the states $A \Omega = |\phi \rangle$ and $C \Omega = |\psi \rangle$

To have the quantity $\langle \phi | B | \psi \rangle$

All obtained from the vacuum

So I guess that the whole unitary inequivalence business in AQFT is translated by the choice of the original state $\omega$?

Jaime Gallego

21:31

I don't understand my Philosophy teacher. He gives us "the best notes that a pupil wrote last year" and they're written like a stream of consciousness. Garbage in, garbage out, I guess.

Slereah

that's philosophy for you

nbro

Scientists Achieve Direct Counterfactual Quantum Communication For The First Time: sciencealert.com/…

Actually, the original paper was first published last year.

ACuriousMind

I know that I would regret clicking on that link

nbro

@ACuriousMind Why do you say that?

0celouvskyopoulo7

@Slereah pretty good deal for $20

the used book market is pretty sweet if you can get good condition ones

ACuriousMind

21:38

Because most pop-sci articles on anything quantum and in particular about "quantum communication" or teleportation are usually horrible and full of mischaracterizations and needless exaggerations

Mithrandir24601

Well, here's the actual paper: pnas.org/content/114/19/4920.abstract

0celouvskyopoulo7

this one is unused, but a 60% discount

Slereah

@0celouvskyopoulo7 I don't even mind poor condition ones, really

nbro

@ACuriousMind Well, if you read the abstract of the original paper, the article seems to be quite faithful to it

ACuriousMind

Now, that's a clever trap: To determine whether you're right, I have to click on the link!

nbro

21:40

lol

0celouvskyopoulo7

Rick Ross - Trap Trap Trap ft. Young Thug, Wale

►

nbro

Noooo!!! ahahah

ACuriousMind

Is that a "modern" rickroll? :P

Mithrandir24601

What do they mean here by 'counterfactual' - just sending info without transmitting any particles?

0celouvskyopoulo7

@ACuriousMind No.

nbro

21:41

Btw, if you want to join me for serious discussions regarding hip hop music.

Hip hop

General chat to talk about hip hop and related derivatives or ...

ACuriousMind

@nbro ::flees in the opposite direction:: ;)

nbro

I shouldn't be spamming (last time I was banned for 30 minutes on SO because I did this).

0celouvskyopoulo7

@ACuriousMind Oh come on

It's not like rap is worse than metal

they're both degenerate

ACuriousMind

@nbro Ah, some rooms are pretty strict with their "on-topic" policies, we're not.

0celouvskyopoulo7

Ok, why do people think $Spin(n)$ is acceptable typesetting

Mithrandir24601

21:43

Huh - it turns out that I agree with Vaidman on this one :) - arxiv.org/abs/1605.02181

0celouvskyopoulo7

It looks awful. Do people not see that?

ACuriousMind

@0celouvskyopoulo7 I don't think most people think about it at all when they type that - it's just the easiest to type on LaTeX.

Mithrandir24601

@0celouvskyopoulo7 It does look awful :/

0celouvskyopoulo7

21:56

@ACuriousMind wtf is it with German math books using quantifiers

Slereah

$\mathfrak{Spin}$

Jaffe's paper on the GNS construction is pretty good

0celouvskyopoulo7

oh no

$\mathscr{Spin}$

huh

$\mathscr{abc}$

I...thought mathscr worked on lower case?

It's appearing upright for me.

ACuriousMind

@0celouvskyopoulo7 I don't know, I've never read a German math book (except for the textbooks in school, and they didn't have quantifiers)

0celouvskyopoulo7

Oh no

Witt's theorem

Slereah

0celouvskyopoulo7

22:06

Where did I read about this before

Slereah

well things are much clearer now

0celouvskyopoulo7

I like when people write ??? in diagrams

Slereah

it is the mystery case

0celouvskyopoulo7

Ah

Witt's theorem is in Wolf

@ACuriousMind halp

If $(V,B)$ is a finite-dimensional non-degen quadratic form, then for every maximal null-subspace $W\subset V$, $\dim W\le \frac 12\dim V$.

I guess it has to be a proper subspace?

ACuriousMind

How could it be improper?

0celouvskyopoulo7

22:11

Because in 2-D Minkowski, the null vectors generate the whole thing

ACuriousMind

If $V$ is null, then the form is degenerate

0celouvskyopoulo7

$(1,1)$ and $(-1,1)$ are linearly independent and null

ACuriousMind

@0celouvskyopoulo7 I think a null subspace is a space in which every vector is null, not one which is merely generated by null vectors.

0celouvskyopoulo7

it says that the definition is $W\subset W^\bot$, but clearly then $V$ is null...

ACuriousMind

@0celouvskyopoulo7 Hm? $V^\text{whatever that symbol is called} = 0$, right?

0celouvskyopoulo7

22:13

God, fucking algebra

Slereah

$\perp$

0celouvskyopoulo7

Yeah

Nevermind

Slereah

perp

as in perpetrator

0celouvskyopoulo7

Hmm?

It's \bot

Slereah

$\bot$

Hm

well perp also works

Why bot?

0celouvskyopoulo7

22:14

and $\top $ is \top

Slereah

oh, bottom

0celouvskyopoulo7

@Slereah top upside down

Slereah

What is the name of the quantum algebra that also includes unbounded operators

ACuriousMind

@Slereah Oh right, how could I forget the perp symbol

I wonder if anyone wrote a paper named "Finding the $\perp$"

0celouvskyopoulo7

Because you've abandoned regular math

ACuriousMind

22:18

@Slereah "Spawn of hell no mathematician wants to deal with"?

0celouvskyopoulo7

this

it's not a TVS

so fuck it

Slereah

"I don't know" would have worked :p

0celouvskyopoulo7

I mean really, who wants to deal with stuff like that

You need to set a BS limit on your math.

Slereah

Who wants to work on math for physical theories when you can do abstract nonsense

0celouvskyopoulo7

For me, if it involves (a) Noetherian rings, (b) homology with coefficients outside of $\Bbb R,\Bbb Z$, (c) vector space that's not an LCS, (d) relative homology, (e) representation theory, (f) categories, it's simply not worth the effort.

Slereah

22:21

what about if it involves set theory

0celouvskyopoulo7

I don't even know of mathematics that involves actual set theory.

Slereah

What about

set theory

It involves a lot of it

0celouvskyopoulo7

Besides set theory, of course.

Slereah

You probably use set theory

That is what $\cup$ and $\cap$ is all about

0celouvskyopoulo7

I don't know any of the ZF axioms

I disregard classical logic anyway.

Slereah

22:23

most of them are fairly simple

Mostly they're just existence theorems

Existence of an empty set, existence of the integers, existence of the union of two sets

existence of the power set

0celouvskyopoulo7

@ACuriousMind wot's an anti-involution

$\gamma^{2}=-1$?

oh

it's an anti-homomorphism

ACuriousMind

I would've guessed either of those, I don't know which one is the one your text means

0celouvskyopoulo7

$\gamma(xy)=\gamma(y)\gamma(x)$

Sir Cumference

Howdy

heather

@Sir hello =)

Sir Cumference

22:30

@heather Care to test something? :)

heather

what sort of thing? sure!

Sir Cumference

@heather I wrote a userscript here:

1

Q: Regional 12-hour timestamps

This script is a modification of Kip's "Display absolute timestamps (in local time)"; I have his permission to post this. Most of the credit for the script goes to him. About This script displays timestamps based on your timezone in 12-hour format. This is pretty convenient for anyone who doesn...

Need to know how useful it is

You'll need Tampermonkey though

heather

ooh, nice, converting into your own time - does it work in chat?

Sir Cumference

@heather Not yet, though I'll try to get around to it

heather

okay, cool. i don't think i have tampermonkey - is this a "see if it works" test, or a "how useful do you think" test?

because if it's the latter, two thumbs up!

Sir Cumference

22:32

@heather Both

If you're on chrome, you'll need to download tampermonkey from the chrome store

chrome.google.com/webstore/detail/tampermonkey/…

It lets you modify websites with JavaScript (from your perspective, not everyone's)

Bernardo Meurer

@heather Don't touch tampermonkey

It's like cigarettes

Sir Cumference

@BernardoMeurer Wait what

You just hate JS, don't you?

Bernardo Meurer

@SirCumference Also that

Sir Cumference

It's not that bad of a language

It's definitely nice to know

Bernardo Meurer

Javascript is much like HTML

Sir Cumference

22:37

@BernardoMeurer ??

Bernardo Meurer

It couldn't have seen how it was going to be used

Sir Cumference

Oh chill. If you are on the internet as much as me, JS is really handy

Bernardo Meurer

I blame Netscape for all this mess

They ruined the internet

Sir Cumference

Plus it's a good language for beginners

0celouvskyopoulo7

wtf is going on

can we PLEASE stop having CS conversations here

Sir Cumference

22:39

You said the same thing about the JEE...

0celouvskyopoulo7

yes

this is a physics chatroom, not CS

Sir Cumference

And astronomy

Most of the time the chat talks about anything but physics

0celouvskyopoulo7

and that's wrong

heather

like math ::ahem 0celo::

ACuriousMind

@0celouvskyopoulo7 Are you calling your own conversations wrong?

heather

22:42

or video games ::double ahem 0celo::

0celouvskyopoulo7

@ACuriousMind How so?

ACuriousMind

@0celouvskyopoulo7 ...because they're rarely about physics these days?

0celouvskyopoulo7

@ACuriousMind Would you believe that my end goal is physics?

ACuriousMind

@heather He doesn't play them that much anymore, so I don't get to talk about them :'(

0celouvskyopoulo7

@ACuriousMind Huh? I play games all the time

ACuriousMind

22:43

@0celouvskyopoulo7 If you said so, yes

@0celouvskyopoulo7 Anything but Skyrim?

heather

@ACuriousMind =/ sad.

0celouvskyopoulo7

@ACuriousMind Metal Gear before that

heather

i don't play anything but minecraft, and that rarely.

0celouvskyopoulo7

These are nontrivial games

I played Fallout 3 before that

I want to play half life

But who knows when that will be

Sir Cumference

> Physics chatroom...

@0celouvskyopoulo7 If the end goal of all math is physics

Which isn't the case

0celouvskyopoulo7

22:46

@ACuriousMind Ok my end goal isn't physics, I just happen to be writing my thesis on GR

So right now I consider it to be physics-oriented

ACuriousMind

@0celouvskyopoulo7 Oh, right

@0celouvskyopoulo7 Did you play the other ones? I forget

0celouvskyopoulo7

Play what other ones?

I haven't played any half life.

I got all of them on a humble bundle

I have too many games to play :P

Sir Cumference

@0celouvskyopoulo7 Love this conversation

Nov 6 '16 at 7:25, by John Rennie

0celo7's new avatar? It's an ocelot kitten. Very cute too :-)

0celouvskyopoulo7

That's when I got that horrible ban for a year

@ACuriousMind My avatar doesn't show up for me

What do I do?

ACuriousMind

@0celouvskyopoulo7 Please easy on the totalitarian comparisons, I've had enough of those for a long while ;P

0celouvskyopoulo7

22:53

@ACuriousMind You know that saying "if everyone calls you an asshole"

or maybe it's if you think everyone is an asshole

vOv

:P

irony mark

pls no ban

how do I fix that?

ACuriousMind

Did you reload the page?

0celouvskyopoulo7

Seriously?

Many times.

heather

::jumps up and down:: i just got a response from a professor (I asked a few questions about a research paper they wrote)!!!!!

0celouvskyopoulo7

pls

I emailed a Nobel prize winner once and got an answer.

A senile answer, but an answer.

Sir Cumference

My profs talk about their papers in class

heather

22:59

@0celouvskyopoulo7, yeah, well, still. I'm happy.

and I learned something.

0celouvskyopoulo7

why

heather

i asked a question i didn't know the answer too. i got an answer. i learned something.

0celouvskyopoulo7

23:22

@ACuriousMind what did one call a -morphism before Bourbaki

Did they come up with the terminology?

Or was it surjective/injective they came up with

ACuriousMind

@0celouvskyopoulo7 no idea, not a historian

0celouvskyopoulo7

@ACuriousMind you know Ancient Greek and Latin!

Don't be silly

You're basically Herodotus

ArtOfCode

@0celouvskyopoulo7 Ctrl-Shift-R (Chrome) for hard reload

ACuriousMind

23:41

@0celouvskyopoulo7 Well I can (could) read him, but I am not everyone I can understand!

heather

i don't suppose there's any chemistry people around here? the periodic table is pretty quiet.

ACuriousMind

Am I a chemistry person if I'm the son of two chemists? ;)

Hip hop

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