The h Bar - 2017-12-10 (page 1 of 6)

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12:39 AM

@ACuriousMind yo

16

A: How does classical GR concept of space-time emerge from string theory?

First, you are right in that non-Minkowski solutions to string theory, in which the gravitational field is macroscopic, it should be thought of as a condensate of a huge number of gravitons (which are one of the spacetime particles associated to a degree of freedom of the string). (Aside: a poi...

"First, you are right in that non-Minkowski solutions to string theory, in which the gravitational field is macroscopic, it should be thought of as a condensate of a huge number of gravitons"

can that be made at all precise?

I don't remember seeing anything like that in string theory

the background seemed to be god-given

@0celo7 Yes. A modification of the spacetime metric has exactly the same form as the insertion of the vertex operators of gravitons when computing scattering amplitudes. So whether you consider a non-Minkowski metric to be a "background" or an expectation value of a bunch of gravitons is kind-of a matter of taste

time for a new pic

@ACuriousMind How does this work when the spacetime doesn't admit a flat metric?

any ideas?

@0celo7 This doesn't depend on what you start with - you can fix a non-flat metric and view modifications of it as a graviton condensate. What you declare a background and what a graviton effect is arbitrary

It's "natural" to consider a flat metric as the "graviton-less" state, but I don't think there's anything forcing that view upon us

12:50 AM

flag metric?

:P

@ACuriousMind Well that's an interesting question

there are manifolds with no flat metrics

so those must have gravitons?

seems kinda weird

Well, condensate here essentially means the VEV of the graviton field is non-zero

I'm not sure that's weird, there's nothing weird about the Higgs having non-zero VEV after all

@ACuriousMind maybe not to you!

@ACuriousMind

i.redditmedia.com/…

1:25 AM

@0celo7 what's good all around math/phys book to read for leisure?

kinda of like nakahara but more physicsy

1:37 AM

Physica electromagnetica

Physica electromagnetica de campo electromagnetico et effectu suo in particulas onus electricum habentes tractat. Theoria Maxwelliana vim electricam et vim magneticam in formam theoriae relativitatis speciali congruentem unit. Aequationes Maxwellianae per se describunt campum electricum et campum magneticum et eorum causam imperfectam in particulis onus habentibus. Aequatio Lorentziana vim in particulas onus habentes a campis electricis magneticisque effectam describit. Aequationes Maxwellianae in vacuo sunt basis doctrinae lucis electromagneticae in quo celeritas lucis ...

maybe?

gets the cake for weirdest corner of the internet I've found in a while

lol

what is that

english plz

that

is Wikipedia in latin

urgggggg

i didn't even click it

or read it

you got me

@EmilioPisanty I stand in awe

@ACuriousMind I know

there's a ridiculous amount of stuff there

1:41 AM

Impressive dedication

but I mean, surely no one is actually reading that to learn, right?

maybe the articles about Julius Caesar or whatever

but who learns physics in latin?

intellectuals

and, as a converse, if you're translating the physics pages into Latin, who the hell are you writing for?

it's just an enormous monument to idleness, I should think

If we get time travellers from the middle ages these pages might come in handy

wait...

how would that even work

1:44 AM

Or, conversely, a printout of that would be nice to take with us in journeys to the past

you mean if we time travel to the middle ages?

yes

hmm wait i want to fit in too

or, in converse, no

hope i did that right

@ooolb Berger, “Nonlinearity and Functional Analysis”

@ACuriousMind Would it? You'd probably get executed for witchcraft

@ooolb Oh, more physicsy

Well, I didn't plan on showing it to the inquisition :P

@ooolb no clue then

but Berger is still a good math/physics book

if you like legitimate calculus of variations that is

@ACuriousMind Want to do some hellish calculations for me?

2:00 AM

Not particularly, no :)

urgh

I have to generalize an inequality to when something is nonconstant

and it makes...everything worse

the calculation is already ridiculous

step 1 is to let $\lambda$ be a $C^1$ function in i.gyazo.com/cb89fafec08d2d691b0642403e30596f.png

ugh

2:18 AM

@0celo7 what level is it

i only know physicist math

the shady kind

Analysis tends to be all over the place

if you know what the final result should be, it's a 2/5

but right now it's a 5/5 because I'm probing blindly

I might need a sharper estimate than I get naively

hmm i remembered something

Aug 11 '15 at 16:01, by 0celo7

@ACuriousMind I want to have an analysis fetish for some reason

eww

this is interesting

did it work out?

no

I hate analysis

it's like a heroin addiction

2:26 AM

makes sense

these estimates are actually quite crude

well, the result isn't fun to write

but it's ok

3:18 AM

@0celo7 you alright?

you feel different to me.

yes?

what does that mean

idk

any cool maffs going

@BalarkaSen yes

good, good

3:29 AM

@BalarkaSen I'm working on gradient estimates for conformally harmonic functions. What are you up to

Working on schoolwork. I have approximate plans to make infinitesimal progress on Forster today

There's so much to learn I keep getting confused about what to do and end up doing nothing

I'll pick something for a change

I need to do my fluid mechanics final

but this proof has got me ensnared

3:49 AM

i just went out to buy some peanut butter

but they didn't have any

dunno what to do now

well this proof is actually garbage

...the statement isn't even true

damn, I had the inequality backwards in my mind

@ooolb its a PhD level problem :o

dunno what your problem is

did you try asking a PhD?

@SirCumference howdy

I was given an honorary PhD

show

in my group's dropbox:

4:01 AM

ah i didn't see

who's mat?

wot you're dr. ryan?

the organizer

@ooolb it's an inside joke, but yes

lmao

urgggg

i just ate a bunch of plain bread because i didn't want to go buy peanut butter anymore

but i regret it now

I wonder if I can just cut out part of the manifold and still have the gradient estimate make sense...

As long as everything is bounded near a compact boundary I completely buy it.

If I'm really unhappy I can surgery on an end and kill it with a cutoff function there

In conclusion, this proof is probably correct

i wonder if i can still go buy peanut butter and not be full so i can eat it tonight

Actually, I don't even really need the constant to be independent of the function, just a global one

gg yau

Captain Bohemian

4:07 AM

i am hungry but can't think of what to eat.

peanut butter?

syrup sandwiches

Captain Bohemian

peanut butter can't cure hunger

did you ever try eating it with a spoon

in Mathematics, 6 mins ago, by Kevin Driscoll

@BalarkaSen This $U$ is real weird. Its an annulus around the equator of a sphere, but antipodal points are identified. So for example rather than rotating by $2 \pi$ to get back where you starter, you can also rotate by $\pi$ and then go down through the equator. Which means if I cut along the equator, and rotate one of the annuli by $\pi$ then glue it back along the cut equator..... that makes it seem like its just $S^1 \times I$?

4:08 AM

in large quantities

Captain Bohemian

no

I wonder if any of you knew anything in physics that basically go back to the start after a half turn

do it

@ooolb how do you like that ACM's roast of you is pinned?

uhm

he's embarrassing himself

i feel so idc

4:09 AM

nice

@BalarkaSen yo wanna solve an ODE for me?

Captain Bohemian

i don't like peanut butter. i prefer strawberry sauce.

depending on the ODE

@CaptainBohemian jam?

Captain Bohemian

yea

i also have like a couple minutes i can afford

4:09 AM

@BalarkaSen actually a PDE but it's separable

$\psi_{tyy}=\psi_{yyyy}$

boundary conditions...no clue

Captain Bohemian

i am eating strawberry puffs now. But they don't effectively cure my hunger. I think I need to go to some eatery to get some cooked food.

hmmm

when i'm hungry and i dunno what to do

i get bread and peanut butter with blueberry jam

and just stuff it with that stuff until it's gushing out

@0celo7 So it's u_x = v, u_y = w, w_y = v?

and then you solve for $\psi_{yy} = w$

Captain Bohemian

i found dry food can't usually solve my hunger effectively, not knowing why.

it's not dry

then soak it in water first

soggy bread...

it will break

4:18 AM

@BalarkaSen yeah

it's not...quite what I'm hoping for tho

because then you have to integrate twice...yikes.

it looks like a fucked system

Captain Bohemian

so-called dry food i mean noncooked food. I have tried many dry food when hungry, finding only peanuts can solve hunger.

@CaptainBohemian peanuts in peanut butter are roasted

jam is boiled

you just played yourself

@BalarkaSen the nice thing is that you've got some asymptotic conditions that really narrow the space of solutions

like what

4:21 AM

somehow it's enough to determine a fourth-order PDE

I'm not trying to think too rigorously

hm

@BalarkaSen this is actually for an exam so I'm not saying any more

oh ok

@0celo7 law abiding citizen eh

PDEs are out of my league man

4:22 AM

@BalarkaSen will you read my thesis?

i am a simple ODE man

@0celo7 sure

if you make it readable at least

Captain Bohemian

i only like eating peanuts in whole grain, not pulverized peanuts, like peanut butter.

Yes. I am including a lot of background

you're done?

Cool. That'd be dope

4:23 AM

@ooolb not even close

nice

I'm working through the hardest (and most controversial) chapter now

Anonymous

@CaptainBohemian It's not you. Food with high water content makes everyone feel more full (compared to a an equivalent amount of dry food). I think this has some interesting science behind it. You could ask on Bio SE ;).

Captain Bohemian

can negative research result easily be published?

what does that mean

Captain Bohemian

4:26 AM

@Blue i have never visited bio SE.

Narcissus jewel

@ooolb As in, showing something is not the case, rather than showing that it is.

good bot

Anonymous

@CaptainBohemian Hmm. So?

@CaptainBohemian depends if it's controversial

@CaptainBohemian depends on how many people think it's true

Captain Bohemian

4:32 AM

but i guess not many people know the formulation i test because the editors usually spend long to find the referees to review it.

if you really want it published you can put the preprint on vixra

but it's shady af

Captain Bohemian

but i can't upload it there

oh ur not in science

Captain Bohemian

i have graduated and all of my academic emails are all cancelled

vixra doesn't need one i believe

Captain Bohemian

4:35 AM

i used yahoo to publish a paper

lmao

is that even a thing

Anonymous

yahoo!?

Anonymous

gosh

just make a website and upload it there

so ppl can find it if they search

Captain Bohemian

i mean yahoo email

Anonymous

4:36 AM

Also uploading on a peer reviewed site doesn't mean publishing

Anonymous

@CaptainBohemian wtf...

@Slereah uses Yahoo

@0celo7 youtube.com/watch?v=0VaeyqMK0GU

degenerate

sigh, nvm

4:37 AM

@0celo7 what?

Captain Bohemian

i know a uk professor also used yahoo email to publish papers.

Anonymous

@CaptainBohemian What's your paper's topic tho ?

You heard me

Captain Bohemian

gr

@0celo7 say it louder

4:38 AM

ooolb u should listen to vaporwave

i do sometimes

link me up b

feel the vapor

@BalarkaSen retarded question (unrelated to exam): I have $\lambda:[0,1]\to\Bbb R$ continuous in a neighborhood of each point of the domain. That means it's continuous on the whole thing and the image is connected, right?

inhale the vapor

be the vapor

@0celo7 Locally continuous means globally continuous yes

Thanks

Just making sure

4:40 AM

oh right

@BalarkaSen did you mean

listen to

$$\mathsf{V \,\,\,\,\,\, A \,\,\,\,\, P \,\,\,\,\, O \,\,\,\,\, R \,\,\,\,\, W \,\,\,\,\, A \,\,\,\,\, V \,\,\,\,\, E}$$

yes, A E S T H E T I C C M U S I C

I like my music with T H I C C b A S S

like Macintosh Plus リサフランク420 / 現代のコンピュ

I don't get vaporwave

you're not hip enough

4:42 AM

I'll hip your butt

@0celo7 that [song i linked] has a really thicc bassline

@BalarkaSen i can't believe you didn't watch cowboy bebop

should i? i searched around and it looks like a seriously good anime

dude

i am not big on animes

it's not like anime

definitely watch it it's really good

has all the elements i feel you'll like

4:46 AM

very nice, i will

it's episodic

damn

the prof dropped epic hints

with a lil story line but not really

I'm on the right track

@BalarkaSen watch this scene

4:46 AM

@BalarkaSen Do you do any real drugs?

@BalarkaSen youtube.com/watch?v=bn-uxaIZVXI

i love this it's incredibly deep

@0celo7 i do the yellow bugpowder

(dw about spoilers it's episodic)

@BalarkaSen :o

teach me your ways please

Meeting the case officer - 'Naked Lunch' (HD)

4:49 AM

Big Sean & Metro collab!????!?!

@ooolb damn

watch it lol

episode 1 is kind of bad though

don't let it give you a bad first impression

@ooolb what's a good yandere anime?

Captain Bohemian

actually i found using yahoo email to publish papers is better than using academic email if you are just a student or research assistant because academic email will be cancelled some short time after you graduate or leave your position

@ooolb mmkay.

4:57 AM

@0celo7 dude do i look like a dude who watches anime?

i've only seen like 7 animes smh

Yes.

u give off a lo fi hip hop vibe not gonna lie

but good to know you're not an anime boi

@BalarkaSen is that a compliment

i used to listen to lo fi

well, just a general remark on your online appearance. see, guessed that right

@ooolb prolly not

4:59 AM

I listened to lo fi before it was cool

the one good music tastes are pop music and classical music

like in 2015

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