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Balarka Sen

5:02 PM

@yuggib Personally I can't think of "geometry" without a metric.

Algebraic geometry, e.g., isn't technically geometry to me.

I think this is also the convention in general.

yuggib

I don't know why everybody is arguing with me about geometry, since I clearly said that it is something I find boring and uninteresting :-P

Balarka Sen

I am not arguing, just writing down my point of view.

vzn

Balarka Sen

i do not believe it's worth arguing being right or wrong about philosophical point of views

vzn

↑ just got that for an almost-teenager

@BalarkaSen whats new, so you are looking into physics now? like more mathematical physics?

Balarka Sen

5:07 PM

nah

i guess i am slightly curious about a few things in physics i overhear often. but i do not plan to study physics anytime soon

vzn

@BalarkaSen what things?

0celo7

5:23 PM

@BalarkaSen no

@BalarkaSen So Lie groups, symplectic manifolds, contact structures, connection theory, holonomy, are all not geometry?

Natural operator theory

Gauge theory

Balarka Sen

Ah, I guess they are. Things with a form, something something.

I don't know about any of those admittedly.

0celo7

@BalarkaSen I think "geometry" is a manifold + something.

Where that something is not unique to the manifold.

Like a metric -- the topology alone cannot determine a metric.

The topology alone cannot determine a unique symplectic form, a unique connection, etc.

Balarka Sen

true

0celo7

I wonder what the definition was ca. Euclid.

Slereah

5:38 PM

There was only one geometry!

And it was defined by 9 statements and 5 axioms

user218912

6:15 PM

My lung is making a weird snoring sound when I breath.

Slereah

It's cancer

user218912

no.

bolbteppa

"For example, it is well known that Euclidean geometry is a special case of the theory of Hermitian operators in Hilbert spaces" maa.org/sites/default/files/pdf/upload_library/22/Ford/…

Slereah

6:35 PM

@bolbteppa well $R^n$ is a Hilbert space

Bass

@ACuriousMind Never saw so many delta functions cancel each other :) thanks!

Slereah

7:28 PM

How does one obtain what the wilson loops are like, classically

Can I compute an EM field with wilson loops instead of Maxwell's equation

Slereah

8:07 PM

Do the EM ghosts do anything

Or are they just tagging along

NeuroFuzzy

@Bass Just saw your facebook message (about the QFT group)! Any participation is good.

We might have a skype review session with a grad student here at UCSD.

Slereah

8:35 PM

Who does QFT on Facebook

Physics Meta

Q: Deleting copyrighted material

Today I had some issues regarding an answer (now deleted) that I encountered in the Low Quality queue. The question asked for clarification about a solution by Michael A. Gottlieb, and included a screenshot of that solution without its copyright notice. The reviewed answer recommended to ask Mich...

1 hour later…

Andrew Spott

9:42 PM

Anyone have any experience with calculation of higher order susceptibility tensors in nonlinear optics? I'm struggling with a problem with the degeneracies that seems to be glossed over in all the resources I have.

ACuriousMind

10:24 PM

@ChrisWhite Oh well. Thanks :)

@Bass As long as they indeed cancel, everything is good ;)

user54412

10:49 PM

@EmilioPisanty Since when is a person whose life ambition is to claim copyright for Feynman's ideas and then promote himself as God's gift to physics textbook writing "a respected member of the wider community"?

user218912

11:03 PM

which chapters of BBS are bad?

ACuriousMind

11:14 PM

@3750 I read about hundred pages of that and found it utterly and throughly unenlightening.

I think I stopped at the point where they begin to talk about "Kac-Moody algebras" without ever actually defining that term or teaching you how to do any actual computation in them.

user147690

What's this I hear about Kac-Moody algebras?

ACuriousMind

I also strongly recommend to not study string theory without a proper understanding of standard QFT (including "advanced" things like the BRST procedure) and of CFT in particular.

@AlexClark ...is there some sort of bot that alerts mathematicians when certain words occur in this chat? ;)

I'll also have to disappoint you because I can't tell you anything about Kac-Moody algebras because BBS sucks :P

user147690

11:33 PM

My dreams were crushed by the cruelty of the average physicist!

user147690

(average in cruelty I mean, not in ability!)

ACuriousMind

If you believe @0celo7, I'm above average in cruelty.

ACuriousMind

I think that American create a bunch of fake elementary particles to create an echo chamber to win the Nobel prize in physics for a false quark model with fractional electric charge!. — Achmed 1 min ago

Emilio Pisanty

@ChrisWhite Since there exist people, including many students, that respect him? Either way, the argument stands for the abstract case regardless of whether it applies in this particular case.

Slereah

ACuriousMind

11:38 PM

hehe

Slereah

All those conspiracies seem to have a pretty high opinion of the physicist lifestyle

ACuriousMind

You're right, it's kinda flattering

user54412

11:58 PM

Elementary things can not be fractional. It is actually impossible. — Achmed 18 mins ago

user54412

If you guys are sure that I'm wrong, then what are you afraid of!? You know what this too much vote down means!? that mean I'm right!. — Achmed 15 mins ago

user54412

Can't argue with that. I guess he found us Americans out.