The h Bar

The people’s flag is palest pink,
It's not as red as most think.
We must not let the people know
What socialists thought long ago.
Don't let the scarlet banner float;
We want the middle classes' vote.
Let our old fashioned comrades sneer,
We'll stay in power for many a year

Bernardo Meurer

I registered for Ocean Kayaking next term

Balarka Sen

6:05 PM

That's my anthem

Bernardo Meurer

I will die

John Rennie

@BernardoMeurer to be fair, I have an ideologically sound OnePlus 3 but you'd still struggle to replace the battery without specialist kit.

Bernardo Meurer

@BalarkaSen Did you read the DRM essay?

John Rennie

I suspect that's true for most modern phones.

Balarka Sen

@Bernardo The one you put up on your blog?

Bernardo Meurer

6:05 PM

@JohnRennie Hmm

@BalarkaSen ye

Balarka Sen

Nope. I'll bookmark i

t

ACuriousMind

@JohnRennie I dunno, I can just take the battery out of my Samsung phone

0celo7

ACM is a commie, I wouldn't listen to him

@BernardoMeurer M and I are getting google phones next

Bernardo Meurer

@0celo7 Pixel?

0celo7

yes

Bernardo Meurer

6:06 PM

I can't believe M is leaving Apple

Or you

John Rennie

@ACuriousMind which model is that? I can't remember the last phone I had that had a removable battery.

A Samsung S3 I think ...

ACuriousMind

I think it might be an S3 mini, actually. Hm, that might not qualify as a "modern phone"...

Balarka Sen

Cancer causes iPhones. Remember that.

Bernardo Meurer

@ACuriousMind It doesn't

@BalarkaSen Weirdly true

ACuriousMind

But the one time I bought a state-of-the-art phone (the first OnePlus), I bricked it in less than a year, I'm not doing that again :D

0celo7

6:09 PM

how did you manage to do that

Bernardo Meurer

I can't believe I managed to convert an EXT4 to a BTRF partition in-place with no data loss

@ACuriousMind How?

ACuriousMind

@BernardoMeurer Dropped it on a stone floor, broke the screen.

Bernardo Meurer

Damn, sad :/

0celo7

is "idiot" an acceptable word here?

Bernardo Meurer

Lol

ACuriousMind

6:10 PM

Yeah, I really liked it

@0celo7 No, the appropriate word is "drunkard" :P

0celo7

I'm swearing off alcohol

Balarka Sen

Pettibourgeoisie

0celo7

it's the devil's juice

Bernardo Meurer

@ACuriousMind Lesson: If you really like your phone get an ugly cover for it and rejoice

John Rennie

@ACuriousMind there but for the grace of God go I :-)

ACuriousMind

6:12 PM

Although it is the only thing I ever broke being drunk, so I'd say it's an acceptable track record

Bernardo Meurer

@ACuriousMind Hearts? Morals? Tables? Chairs? Glasses?

Only thing?

ACuriousMind

@BernardoMeurer Hm, okay, add a few hearts and a snow shovel.

Bernardo Meurer

I need to ask you a moral question

ACuriousMind

Glasses I only break when sober :P

@BernardoMeurer Go ahead

Balarka Sen

John Rennie

6:14 PM

@ACuriousMind on one occasion I was so drunk I couldn't be bothered to lock my bicycle when I went into the takeaway to buy a kebab. When I came out, yes, the bicycle was gone. An expensive kebab really ...

ACuriousMind

@JohnRennie Ah, that's why I don't take the bike when I plan to drink ;)

Bernardo Meurer

Is it wrong to lure in $n>1$ women to a New Years party, but then actually take an entirely different one as my date?

0celo7

what title should I give the talk

@BernardoMeurer M and I are both dying

our backs hurt from too much sugar

Bernardo Meurer

@0celo7 "On the transmutational characteristic of sexuality in n-dimensional complex fiber bundles"

ACuriousMind

@BernardoMeurer Uh. That depends on what you mean by "lure"

Bernardo Meurer

6:19 PM

@ACuriousMind Invite with an implicit implication of being together and possible intercourse

ACuriousMind

@BernardoMeurer If you're sure you're communicating that implication clearly, then yes, that's wrong

I'm not sure where the moral dilemma is supposed to be, seems rather clear cut to me :P

Bernardo Meurer

Well, I never explicitly said those things

So I don't see what's wrong

It's their own faults for allowing their minds to jump to conclusions

ACuriousMind

Also, regardless of morality, I'm not sure it would be a very enjoyable party when you have several women who expected to spend time with you finding out they're not the only ones!

Bernardo Meurer

@ACuriousMind This is where you misjudge my planning abilities

The party has a friends-only zone which I have access to, and none of they do!

And regardless I have no shame and the house is large

ACuriousMind

@BernardoMeurer Well, I rather had the possibility in mind it could be the other way around: You think they're jumping to that conclusion but they're not, in which case it would be perfectly fine (although questionable if you intended them to draw that conclusion).

Bernardo Meurer

6:23 PM

@ACuriousMind There we go, perfectly moral!

ACuriousMind

Mhhh

Bernardo Meurer

Let the record show it's okay to overpromise and underdeliver knowingly and willingly!

ACuriousMind

I will shed no tear for you if you end up with several drinks in your face and going home alone :P

2

Bernardo Meurer

@ACuriousMind Another mistake, I have no intention of coming back home until Tuesday :P

By which point I'd like to come back alone

Also, I've been forbidden to bring hookups to my mother's house anyway

for unknown reasons

0celo7

Your life is a mystery to me

Bernardo Meurer

6:26 PM

How?

0celo7

you somehow got multiple women to want to have sex with you in the future

how does that even happen?

Bernardo Meurer

I have no idea, I'm always drunk

0celo7

again, a mystery

Balarka Sen

"I'm always drunk" - Hulk, 2017

ACuriousMind

@0celo7 It's all his talking about FREE SOFTWARE

Everyone digs that

Bernardo Meurer

6:28 PM

But mostly it's about being a good salesman

0celo7

@ACuriousMind hmm

Bernardo Meurer

@ACuriousMind You know what, women on average do love that

0celo7

what women are you talking to??

Bernardo Meurer

Iff you're able to sell it as you being an activist who sacrifices his comfort for what's right and tries to help others

which I do :P

ACuriousMind

@BernardoMeurer Sure. It's the passion you're showing, not the topic itself, that does most of the work of letting you seem attractive

Slereah

6:32 PM

the waffles are a failure

Bernardo Meurer

@ACuriousMind Exactly, so Free Software gets you laid

@Slereah Pics

0celo7

I'm passionate about inequalities but most women think I mean something completely different

7

Slereah

Good waffles are hard to make

Bernardo Meurer

@0celo7 Lol

0celo7

and then I go full trump when they think I mean social ones

Balarka Sen

6:32 PM

@0celo7 Beautiful

ACuriousMind

And as much as I'd love to discuss your soap opera of a life, I gotta go get drunk and play cards now

Bernardo Meurer

@ACuriousMind My life has way more drama than a soap opera

Play Go Fish in the name of me

0celo7

@ACuriousMind please don't drink the devil's juice

I tried to explain my work to my sister's skin care person yesterday

I got nowhere

Bernardo Meurer

lol

You gotta improve that skill

I can explain what I want to work with to my grandma

0celo7

computers are far more concrete than hypersurfaces in Lorentzian manifolds

Balarka Sen

6:34 PM

Who cares? Math sucks

I told you that

You work on trash bro

0celo7

@BalarkaSen why don't you leave?

Bernardo Meurer

@0celo7 I guess, I just explain what Optimization problems are and how QC's can help

@BalarkaSen We upload trash

Slereah

@0celo7 just tell them you're a rocker scientist

Bernardo Meurer

@heather When's your birthday?

heather

@Bernardo november

why?

Bernardo Meurer

6:36 PM

@heather So you're like 13 now?

Balarka Sen

@Bernardo Face down, trash begets trash

Bernardo Meurer

Because I was talking to my cousin these days

heather

@BernardoMeurer eh...bit older than that =P

Bernardo Meurer

and she's 14

so I wanted to remember how old you were

Ah, so you're in HS by now?

Right? Is that how it is in America?

heather

yup

Bernardo Meurer

6:37 PM

Oooooh, yeah, I remember now

We talked about this before

me and Dan gave you HS tips

heather

oh yeah

Bernardo Meurer

So, how do you hate it?

heather

it's...not great.

Bernardo Meurer

Yeah, that's how it is

heather

social studies is the worst.

engineering is the best.

Bernardo Meurer

6:39 PM

What even is that

heather

social studies = history, this year it's french revolution/imperialism through modern day, i think

Balarka Sen

@BernardoMeurer it's Not Good/10

Bernardo Meurer

Ah, I used to love that

Balarka Sen

:explosion noises:

heather

to give you an idea of how bad it is, one unit is literally called "asia".

Bernardo Meurer

6:39 PM

I always liked History

0celo7

@heather not good

Bernardo Meurer

@heather Oh, I see

heather

@BernardoMeurer i do too, i just don't like the class.

Bernardo Meurer

So this is how americans become "Americans"

0celo7

People who dislike history generally turn out bad

Bernardo Meurer

6:40 PM

@0celo7 You hate history

Balarka Sen

I like history. Just not the way it's taught.

heather

@0celo7 i dislike history class, which i think is significantly different.

don't worry, i won't be invading russia in the winter anytime soon.

Bernardo Meurer

CONFIRMED @heather HATES THE FRENCH

heather

oh, actually, i've got a funny story

related to the french

i was reading a british newspaper, the telegraph i think

Bernardo Meurer

That's never good

heather

6:42 PM

and it talked about a minor diplomatic scandal relating to the french and cheese

let me see if i can find it, it was hilarious

vzn

> those who do not learn from history are condemned to repeat it --santayana

heather

here we go: Fonduegate: How an incident between a Brit and a French cheesemonger caused a stink

Bernardo Meurer

@heather I refuse to give the Telegraph any traffic

heather

why?

0celo7

@BernardoMeurer how did you get that idea?

Bernardo Meurer

6:43 PM

@heather They are a shitty company :)

vzn

@bernardo enjoying the story of your new years eve sex life, maybe good blog fodder :P

Bernardo Meurer

@0celo7 You told me multiple times

Balarka Sen

@Bernardo (N+1)/N - 1 tends to 0 as N tends to infinity.

0celo7

You’re full of crap

heather

okay, whoever just flagged "I hate the French" needs to tone it down a notch.

Bernardo Meurer

6:44 PM

@vzn I am not posting about my sex life on my blog yet

I need to be at least 40 for that

vzn

uh oh random mod descends for flag o_O

heather

@BernardoMeurer [citation needed]

Bernardo Meurer

Oh, what the hell

Balarka Sen

Thanks, whoever unbanned.

Bernardo Meurer

@dmckee @ACuriousMind @DavidZ @rob This is ridiculous

heather

6:45 PM

who the heck confirmed that flag

@BernardoMeurer seconded, seriously.

Bernardo Meurer

@dmckee @ACuriousMind @DavidZ @rob This is no longer ridiculous

vzn

the tyranny of FLAGS aieee o_O

Bernardo Meurer

@vzn I flagged that, you offended the flags

vzn

@#%& FLAGS :(

heather

@vzn Vexillologists everywhere are offended.

Balarka Sen

6:47 PM

It wasn't a hate speech, just to clarify (even though it's quite obvious). It was tangentially funny given the earlier comment, but I do dislike a lot of French art and French philosophy. Nothing to do with the generic French person :p

vzn

lol wow learn something new everyday

Vexillology

Vexillology is the scientific study of the history, symbolism and usage of flags or, by extension, any interest in flags in general. The word is a synthesis of the Latin word vexillum ("flag") and the Greek suffix -logia ("study"). The constitution of the International Federation of Vexillological Associations (known by its French acronym, FIAV) formally defines vexillology as "the creation and development of a body of knowledge about flags of all types, their forms and functions, and of scientific theories and principles based on that knowledge." A person who studies flags is a vexillologist,...

Balarka Sen

Though I should just put that out just in case.

Bernardo Meurer

@vzn I'm a vexillologist :)

(Not joking)

vzn

← cites wikipedia to throw off ~~censors~~ mods :P

Bernardo Meurer

GOD BLESS ZSTD

heather

6:51 PM

hey, the top physics.se question got mentioned in what if (by randall munroe, the book, not the online version)

(i got a copy for christmas)

Balarka Sen

That's what I call achievement.

In what context?

Bernardo Meurer

amazon.co.uk/RELATIVITY-Theory-Everything-John-Duffield/dp/…

I got this for Christmas

heather

citing it as a source that's better than some scientific journals in one of his answers to a question @BalarkaSen

Balarka Sen

@heather Haha. Wonderful.

heather

@BernardoMeurer lol did you really?

Bernardo Meurer

6:53 PM

@heather No, lol

Slereah

you should

i'm sure it's a hoot

heather

oh, just noticed this particular q&a is on the website here so you can read it @BalarkaSen

Balarka Sen

Ahhhh yes I have read this

I forgot about that

Slereah

"The author obviously knows physics, but not how to teach it. Instead of enlightening the reader as repeatedly promised, he annoys the reader with too much adolescent humor, childish illustrations, unfinished thoughts, irrelevant distractions and in general too much nonsense."

I'm not sure I agree with "knows physics"

0celo7

I’ve got a weird bump on my finger

Slereah

6:58 PM

In two months, Duffield won't be banned anymore

Brace yourselves

0celo7

@Slereah title “What is the mass of spacetime?”

Sound good?

Slereah

It's catchy and simple enough

heather

@Slereah hoo boy. that should be...interesting.

Balarka Sen

Is the volume of the spatial manifold or whatever well defined

Slereah

Hopefully by then he'll be too old to come back

Balarka Sen

6:59 PM

I guess I don't know what volume means for Lorentzian objects

I was thinking in terms of Riemannian

Slereah

not really

I mean you can integrate the volume form

But it's not really a volume

Balarka Sen

what does that mean

also do we know if the integral is finite or anything

0celo7

Probably infinite

Slereah

Well take Minkowski space

It's infinite

0celo7

The entire volume of spacetime is rather uninteresting

Balarka Sen

7:02 PM

Is it interesting if you look at volume of a compact portion as time changes

so the metric changes too

Slereah

Since it's just $\int d^4x$

The spacetime volume is the action of the cosmological term

0celo7

Not really @BalarkaSen. There might be Cheeger-Gromov finiteness theorems for spacetimes, but I dunno.

Balarka Sen

I see

Slereah

I'd suspect that if the spacetime isn't compact odds are low that the volume is finite

Balarka Sen

Thanks for bearing with nonsense questions from a mathematics person for a change :)

Slereah

7:04 PM

Well

I guess you could have like

The spacetime of a ball

$\mathcal M = B^4$

Balarka Sen

@Slereah That's what I was thinking

I mean there are restrictions on the kind of metrics spacetime supports, right?

Slereah

Hm

Balarka Sen

"What are the manifolds with "spacetime metrics" which have finite volume?"

Slereah

If the spacetime is maximally extended and non-compact

Balarka Sen

Or something

Slereah

7:05 PM

Can it have a finite volume

0celo7

@Slereah yeah a ball

Slereah

A ball isn't maximally extended

Balarka Sen

maximally extended as in, complete?

Slereah

unless it has singularities all around

Well not necessarily complete

Maximally extended as in there's no spacetime where the original spacetime is a subset

Balarka Sen

Ah

Bernardo Meurer

7:07 PM

5 and a half hours later, still defragging

Slereah

Schwarzschild is maximally extended but not complete

0celo7

Maximally extended is a thing in Riemannian geometry too. Though I’m not sure why anyone cares

Slereah

Isn't it equivalent to complete in the Riemannian case?

Hm, I guess not

0celo7

Probably not

Slereah

Like the revolution surface with $1/x^2$

Or...

No I don't think that's a good example

Balarka Sen

7:11 PM

Why is that maximally extended

Ok, it's not

Slereah

It is maximally extended, but I thought it might be incomplete

But no I don't think so

Balarka Sen

tfw you change the question to make that answer right

@Slereah I don't get why it's maximally extended.

Take the revolution surface until $y = c$ for some large $c$

You know, I don't really get it. Any compact manifold is maximally extended, right? It can't be embedded as a proper subset of itself because of topology, not even geometry

Is $S^1 \times \Bbb R$ with the product metric maximally extended? Standard ways to embed it inside of itself topologically is to take $S^1 \times (a, b)$ inside it, which aren't complete, so these are not isometric to $S^1 \times \Bbb R$.

Just throwing easy examples to understand what the fuck is up.

Slereah

$S^1 \times \mathbb R$ should be, yes

0celo7

@BalarkaSen turning it into a finite cylinder fucks up tue metric

Slereah

Since there's no regular boundary points

Balarka Sen

7:18 PM

@0celo7 That's the argument.

So what's an example of something NOT maximally extended?

Slereah

You know what's weird though

There's compact manifolds with singularities

0celo7

@BalarkaSen any open set of a Riemannian manifold yhats mot the whole thing

Slereah

Which means that if you append the singular point to it, it is indeed a subset of a thing

I'm not sure what topology it has

Balarka Sen

@0celo7 But $S^1 \times (a - \epsilon, b - \epsilon)$ is isometric to $S^1 \times (a, b)$ isn't it?

Slereah

The typical example of a non-maximally extended manifold is like

$\mathbb{R}_{>0}$

because you can embed it in $\mathbb R$

0celo7

7:21 PM

@BalarkaSen homothetic, Not isometric

Balarka Sen

Ah, now you're talking.

0celo7

Random autocorrect capitalization

Balarka Sen

Okkie-dokkie. I get it now

Slereah

The maximally extended thing is basically to avoid garbage singularities where spacetime just stops because it feels like it

It's generally assumed that a real spacetime is maximally extended

0celo7

But to get maximally extended Schwarzschild you have to glue a second copy

The penrose diagram gets mirrored

Slereah

7:24 PM

Well you don't have to, but it's the most symmetric extension, yes

Balarka Sen

i should study geometry properly

it feels too dry

:(

Slereah

Do you mean

Balarka Sen

the dilemma is stronk

Slereah

EUCLIDIAN geometry?

The only proper geometry

Balarka Sen

Problem, Lobachevsky?

0celo7

7:36 PM

How could geometry be dry

Differential equations are very juicy

Slereah

they do have flows

Balarka Sen

I have to do chemistry now

help me

organic chemistry, no less

Slereah

gross

I hope you like learning nomenclature

I remember organic chem being just learning the giant sheet of nomenclature

Balarka Sen

IUPAC makes me want to die

Slereah

quantum chemistry is where it's at

Also there's RELATIVISTIC chemistry

But I'm not 100% sure if anyone has ever used it

I've got a book on it but how often do you really need relativistic corrections in chemistry

Physics Meta

7:43 PM

0

Q: Why is it written on somebody's profile that it has been visited 0 times, while in fact, I visited the profile 4 times?

I took a look at somebody's profile 4 times. But why it is shown that 0 persons have visited his profile?

Balarka Sen

i should just TeX all these chemical equations up

whats the latex package i need for chemistry again

DanielSank

@BernardoMeurer BEHOLD THE UNIVERSE ON MY HEAD!

ugh, it doesn't show up well

I'm going back to my purple hat.

Bernardo Meurer

@DanielSank lol and lol

CooperCape

This question asks "Is the set of periodic functions from $\mathbb{R}$ to $\mathbb{R}$ a subspace of $\mathbb{R}^{\mathbb{R}}?$ I get that it's probably going to be something to do with proving it is/isn't closed under addition, however short of checking a lot of functions $(f+g)(x)$ to see if they are periodic (and in turn hope that it isn't closed under addition) I'm stuck for ideas? Anyone help? =)

Balarka Sen

Your idea seems right to me. Why don't you try it?

Also is this simply the set of periodic functions, or the set of periodic functions with a fixed period?

CooperCape

7:55 PM

I'm not quite sure what kind to check? I started with trivial things such as cos(2x)+sin(x) but I think that was periodic

Fixed period I think

All functions f(x)=f(x+p) where p is a positive number

Doesn't state whether p is variable.

Slereah

Indicator function of the rational is a periodic function of no period

or of all periods, more accurately