Woe is me

My HE is downstairs

Seems weird to have them remain in a compact region of spacetime?

Of space I could understand

But I'm not sure how he means

Literally he says "All the past-directed null geodesic generators of $H^+(S)$ enter and remain within a compact set $C$"

From what I can see of the diagram it seems to be very much non-compact

@Slereah @0celo7 What do you guys keep talking about? I feel there is nothing new in this chat and that there is nothnig to talk about.. You guys just keep talking about some equations, I have no idea what you are even doing! You guys should make your own room! Sometimes i don't get this place.. You guys are allowed to tall forever on some topic, but eveyrbody else makes a big deal if I do such a thing... What a weird place...

Anyway, you guys should make your own room so we can talk about other stuff...

Well what do you want to talk about

^

@Slereah what diagram

Standard diagram of Misner space

from HE?

@Slereah quantum mechanics (simple quantum mechanics that is) and conceptual physics...

HE p. 172 yeah

Well then do that

We can't talk about things you want unless you engage

@Slereah I will engage, but if you just talk about this stuff (idk what it even is, it just looks like math to me! Is it GE?) en I kinda feel left out and don't feel like talking here.

Well yes but how am I supposed to know what will make you feel engaged

Ask a question or launch a topic, I dunno

We're not here for your entertainment, you know

@Slereah well, have you ever noticed that I keep coming here, noticing that you are talking about some math, and then leave? Does that make you realize that i am not engaged?

No.

Anybody want to talk about Forster theory?

That is what happens when you don't express it with words.

I do not know about it

@Slereah No, the problem is you guys seem to ignore me.. I have been asking what you are doing, what's going on, etc. yet you ignore Like I dont exist..

@Slereah QM?

Forster theory

Well currently I am reading about the chronology protection conjecture

what is that?

I'm currently trying to understand why geodesics even make sense

It's a loose set of theorems that may forbid time travel in general relativity

@Slereah oh.. is that what you were talking with john duffield?

No

I don't talk with John Duffield.

Sadly, I do.

@Slereah why not?

@0celo7 what is so sad about it?

@Slereah Your wisdom knows no bounds

Talking with him is not particularly fruitful

@Slereah i guess..

@NeuroFuzzy do you know anything about normal neighborhoods on compact manifolds

Do you know about exciton transfer?

no

@0celo7 Nope. I am good with real analysis but never did anything with compactness on manifolds. Lol remember when like six months ago I asked you about paracompactness? I think that was the last time I touched it

Paracompactness isn't compactness >:|

ok.. I guess I gotta go.. see you!

the h Bar has changed a lot from the old days (i.e. april-may)

@Slereah Yep.

I've been here the whole time

it's the same place

"In order to understand some of its pathologies C.W. Misner introduced in a seminar entitled Taub-NUT space as a counterexample to almost anything"

heheh

@0celo7 no, it is different.. The community has changed, the topics have changed, a lot has changed...before people like alarge, QMechanic, Kyle Kanos, Danu, and others used to come... Now it is just you guys...

I probably scared them off.

@0celo7 you probably did...

Wait

@0celo7

what

Are the null generators inside the hypersurface or orthogonal to it

uh

that's not well defined

because null vectors are parallel and perpendicular to themselves

Well yes, but like

Are the curves that they generate inside the surface

Or going through it

@TanMath good

@Slereah hmm

let's check the Waldino

@TanMath That's pretty dramatic...

Also some of those people still come here

@Slereah very rarely...

@Slereah when was the last time QMechanic came here, for example?

Seems a bit presomptuous to assume they left because of us, too :p

yesterday

@Slereah it was just a joke.. for some reason they left, I don't know why..

5 hours ago

Maybe just life

It's not always easy to make time for the internet

Qmechanic never actually talked

He hasn't been in here as much lately, that is true.

KK left because of his new job

Danu comes here often

alarge pops in all the time

^^

that damn @dmckee

::snort::

@dmckee you alright?

maybe we're about to get rid of him /s

Hm

mb I should just compute the null geodesics by hand

It's not too hard

Misner space is just flat space

@TanMath I do agree that things have changed.

Just gotta coordinate transform some straight lines

It's not necessarily a bad thing, though.

@Danu what are you doing here

You left ages ago

Que?

You left this chat because things have changed, didn't you read

what has changed

I haven't noticed it

Because you are part of the problem

You coming here :P

@Danu when did I actually come here

@Slereah I wouldn't call it a problem.

It's just different---but that's how things go, y'know :)

@0celo7 Somewhere in the last academic year.

$\int_0^1 x^{-x}\,\mathrm{d}x = \sum_{n=1}^\infty n^{-n}$

D:

@Danu been downhill from there, eh?

@0celo7 As my earlier comments (should) make clear, I don't attach any value judgment to the developments.

Neat