The h Bar

0celo7

23:00

uh, ok

@Slereah where do the curvature terms go in Maxwell's equations

it seems like you'd have to make the shape of the Gaussian depend on the curvature somehow

Slereah

$F^{ij}_{;i} = j^{j}$

0celo7

so it cancels it in Maxwell's equations

>$j^j$

you monster

you need $\Box A^\mu=R^\mu{}_\nu A^\nu$

Slereah

If you use the Lorentz gauge $\nabla A = 0$, then it is $-\square A^i + R^i_j A^j = j^i$

0celo7

are these space indices

or are you a monster

Slereah

I am lazy

0celo7

23:05

then use a,b

Slereah

y

0celo7

does $j=0$ for a wave packet

because that's what I assumed

Slereah

Well we are doing it in empty space here

0celo7

wait a moment

Slereah

So yes

0celo7

23:06

we need @ChrisWhite

isn't that equation just

a weird wave equation

with a constraint

Slereah

In empty space we have $A(x) = f(u) + g(v)$

Just pick $f(v)$ to be a Gaussian

Apply it

Look at the movement of the center of the gaussian

0celo7

what is $f(v)$

or $f(u)$ or $g(v)$

what is $u$ or $v$

Slereah

Oh wait, I guess that's only for flat space

They are null coordinates

0celo7

ohhhh

Slereah

$x + t$, $x-t$

although I guess that if the spacetime is without sources, we can assume it Ricci flat :p

But then $\square$ is still the Laplace beltrami operator

0celo7

23:09

can we?

Slereah

So that doesn't help too much

Might be complicated to prove

0celo7

the EM EMT has F not j in it

Slereah

If true

Hence the approximation I suppose

0celo7

what is the EMT for EM

Electromagnetic stress–energy tensor

In relativistic physics, the electromagnetic stress–energy tensor is the contribution to the stress–energy tensor due to the electromagnetic field. The stress–energy tensor describes the flow of energy and momentum in spacetime. The electromagnetic stress–energy tensor contains the classical Maxwell stress tensor that governs the electromagnetic interactions. == Definition == === SI units === In free space and flat space–time, the electromagnetic stress–energy tensor in SI units is where is the electromagnetic tensor and where is the Minkowski metric tensor of metric signature (−+++)...

that can be nonzero

it's not Ricci flat dude

there's a light ray causing gravity beyond Ricci flat

Slereah

Test field limit

You butt

0celo7

23:12

that's still an approximation!

Slereah

Well then solve it exactly

what do you want from me

You need to solve it exactly for every spacetime

0celo7

@HDE226868 So I read the first few chapters of an AnCap book

DanielSank

@ACuriousMind Holy $&!%

0celo7

@HDE226868 It starts off by saying there's no basis for ethics and morals to vary from culture to culture just as the laws of physics do not vary from planet to planet.

Slereah

Too bad it still does

0celo7

23:15

Furthermore, relative ethics are what allow for wars and all atrocities that have been "justified."

Slereah

Moral objectivity people are weird to me

They can't accept that the universe doesn't agree with them

0celo7

@HDE226868 The idea is that "right" and "wrong" should not depend on whose soldiers patrol the streets.

HDE 226868

@DanielSank See also meta.stackexchange.com/questions/269600/…

@0celo7 Interesting.

@0celo7 Ah, interesting. Just what you had been saying.

0celo7

@HDE226868 It also plainly says that we should take certain ethical lessons from children.

Slereah

Should we

Children are pretty shitty

0celo7

23:17

That the child's idea of "why does X get to do Y but I can't" is a very important thing to consider.

HDE 226868

@0celo7 How old can "children" be?

@0celo7 Absolutely.

0celo7

@HDE226868 Not sure.

DanielSank

@0celo7 I disagree with that strongly.

0celo7

@DanielSank Most people do.

DanielSank

The only possible way to define morals that doesn't boil down to religion is in a sort of Darwinian sense.

Slereah

23:18

not really

0celo7

Sadly.

Slereah

a fair amount of people believe in objective moral

0celo7

@DanielSank Religion?

Slereah

Darwinism doesn't really define morals

0celo7

Tell that to every atheist AnCap.

HDE 226868

23:18

@0celo7 Others besides me and ACM?

Slereah

Morality is more of a societal thing

0celo7

@HDE226868 You cannot believe in a moral government and accept objective morality.

Theft is bad...unless the state does it, in which case it's alright.

HDE 226868

@0celo7 I agree with that, although I don't believe in a moral government. If you try to right laws based on morals, then you'll mess up somewhere. You'll never be able to eliminate all cases of contradiction between moral codes and the laws.

@MadScientist The question has been phrased very cleverly to insinuate something wrong at Physics. In fact there is a deranged user who is slinging wild accusations at a number of established users. As in, this person desperately needs mental help and is unsuited for living in society, whoever they are. Yes, accusations were made against a moderator, and yes those have been deleted, but if you could see them you'd see the madness for what it is. — Chris White 18 hours ago

Thought you might find that summary interesting.

Slereah

I don't think defining morals from axiomatic principles is too useful, really

It never really works out

0celo7

@Slereah There are certain principles that can be "derived" but I'm not sure how bullshit that is.

Slereah

23:22

Sure, some of it is partly from biology

DanielSank

@0celo7 You can't invent absolute morals without just making them up.

Slereah

But even then it's not precise

0celo7

Of course, there's the good ol' "if a moral system allows rape, it's not moral".

Due to...Aristotle?

Slereah

Was Aristotle a rapist

DanielSank

@Slereah No, but I can define morals in terms of Darwinian ideas!

Slereah

23:23

Can you

Darwinian ideas just tells you what happens

Not what should be

DanielSank

@Slereah Exactly!

Morals can be thought of what is, not what should be.

ACuriousMind

@DanielSank Yeah.

0celo7

@HDE226868 A true AnCap says that's not an issue because most laws are immoral anyway.

Slereah

WHO IS JOHN GALT

0celo7

There are AnCap "laws" but these are societal things.

@Slereah Some fucker in Atlas Shrugged

Slereah

23:24

Whoooo is John Gaaalt

0celo7

He is

HDE 226868

@0celo7 I forgot about the "An" in "AnCap".

0celo7

wait

Slereah

Randroids are always good for a laugh

But only one

0celo7

@HDE226868 AnCap laws are not enforced by the state.

Slereah

23:25

They get old pretty fast

0celo7

They are enforced by business owners.

ACuriousMind

@Slereah Hm, I was also thinking that right now. I wonder why? :P

Slereah

Even worse

HDE 226868

@0celo7 Well, yeah.

0celo7

Rape the local bar maid? Good luck getting food.

Slereah

23:26

What if you are a big strong man

and can still get food

0celo7

Theft?

Or living innawoods?

Slereah

Well yes

Who's gonna stop you

YOU ARE BIG AND STRONG

0celo7

Are you robbing people?

Slereah

^pictured

yes

0celo7

Is that shark real?

Slereah

23:28

If he is, he seems alarmed

0celo7

I'm not allowed to ping ACM anymore...

Aww

ACuriousMind

@DanielSank ? Commonly, "morals" are precisely thought of as the code of "what should be". Are you redefining what we mean by "morals"?

Slereah

Also do we have to discuss this

All political decisions between random assholes are basically always the same

Pretty sure that discussion was had like 4000 years ago

ACuriousMind

@0celo7 ?

0celo7

Ignore that.

DanielSank

23:29

@ACuriousMind I won't call it "redefining" until you propose a definition :D

ACuriousMind

:25616832 Chill out, you may ping me

Slereah

Morality is the set of actions that will be met with societal approval and the set of actions that will be met with frowny faces

0celo7

no ACM you said not to

Slereah

^a frowny face

0celo7

@HDE226868 Another issue is that one should be able to derive the basic truths of everyday life from "big truths" aka "principles"

Slereah

23:31

Yeah but you won't

DanielSank

@Slereah Hah, that matches exactly with my Darwinian idea.

0celo7

So "don't ping ACM" may be derived from "don't be an annoying shit"

Slereah

The human brain doesn't work like that

DanielSank

That's not a "should be" definition. That's a "what actually is" definition.

0celo7

Or "don't punch" follows from "violence is wrong"

Slereah

23:32

Yes, but it's not darwinian

0celo7

The problem with relativistic morals is that there are little truths that defy the principles.

ACuriousMind

@DanielSank Heh, alright, being on the defensive is easier, eh? Okay: A "set of morals" is a prescription of how human beings should and/or should not act in particular (or general) situations.

Slereah

@0celo7 what about punching a murderer

So he doesn't murder

Or punching a baby crying on a plane

0celo7

@Slereah Self defense?

Slereah

Both are obviously good

Well yes but that doesn't fit your definition

0celo7

23:33

@Slereah Actions taken to prevent violence are not violence with these definitions if I'm correct.

Slereah

But they are in themselves violent!!!

Wait, what if both people want to commit violence, and decide to stop each other

Are they both justified

0celo7

I think violence here is defined as unwanted force taken without reason.

Slereah

But violence is always for a reason

ie baby crying

0celo7

Hmm

Slereah

Morals taken from a few axiomatic ideas never feel right

Because the real world is too complicated and humans don't really function on such principles

0celo7

23:35

Is a murder murdering someone defending themselves from being murdered legit?

Slereah

I say kill everyone

0celo7

so ACM why can't I ping you anymore

if you don't mind humble 0celo7 asking

ACuriousMind

@0celo7 I said chill out you may ping me

0celo7

I am chill

It's actually freezing

now pinging you feels wrong

like calling a prof by his first name

Slereah

Really I feel for the most part people don't have that different moralities

0celo7

23:37

or...dear god...wearing a shirt that isn't ironed

Slereah

They just have different ideas on how the world works

DanielSank

@ACuriousMind Sounds like a religion.

0celo7

@Slereah indeed

That's the point of Universally Preferable Behavior

ACuriousMind

@DanielSank Yeah, every religion has its morals.

0celo7

Take the stuff that 99% agree on

Slereah

23:38

If you ask them "Why do you think X is wrong", they will tell you a reason

0celo7

And iron out the inconsistencies

DanielSank

@ACuriousMind No, I mean that sounds like the definition of a religion.

Slereah

And not just "It is axiomatic in my moral system"

DanielSank

@0celo7 That's descriptive, like Darwinism.

0celo7

@DanielSank A religion literally has a deity (or pantheon)

Slereah

23:38

If witches really do put curses on you, would it not be a good idea to burn them

@0celo7 what about buddhism

HDE 226868

@0celo7 Not necessarily.

Slereah

Can we stop this conversation, really

0celo7

example?

Slereah

It's the eternal "random assholes discussing morality"

0celo7

merriam-webster.com/dictionary/religion

@Slereah I'm not completely an asshole

Slereah

23:40

In French we would call it "une conversation de bistrot"

0celo7

and legs

I have some arms

Slereah

a pub discussion

HDE 226868

@0celo7 Taoism.

Slereah

The kind of debates that random pub goers would have

0celo7

@HDE226868 do they worship nature

Slereah

23:40

Taoism has some divinities, IIRC

Confucianism doesn't, though

0celo7

wait wait wait

what is it

Slereah

Though I wouldn't call confucianism a religion

0celo7

if there's no deity

how are we defining religion

Slereah

"religion" is poorly defined

HDE 226868

@Slereah I don't think anyone would call it a religion.

0celo7

23:41

If I define religion using a deity and you don't, we shouldn't argue about what's a religion

Slereah

Religion is kinda "those systems that have some points in common"

ACuriousMind

@DanielSank Hm, and here I thought religions were about the supernatural and mystical.

HDE 226868

@0celo7 Fair enough.

Slereah

Religions are a mixture of like

Divinities, the supernatural, cosmology, moral system, rituals

ACuriousMind

@DanielSank But this just tells me you apparently disagree with my definition of morality, so what is yours?

DanielSank

23:42

@ACuriousMind Interesting. I always equated "religion" with "faith".

0celo7

cosmology

@ChrisWhite is a pastor

Slereah

Religions love a good cosmology

Not all of them, but still

A lot of them with eggs or water

Because we know a good metaphore when we see one

GUYS

IT COMES FROM AN EGG

ACuriousMind

@DanielSank Hm, no I think there are many things one can have "faith" in that I would not call a religion.

Slereah

Also what is faith

ACuriousMind

For one, "faith in humanity".

0celo7

23:43

I have faith in this building not collapsing

HDE 226868

I have faith in the system of Stack Exchange.

On most days.

0celo7

Of course our CE department is pretty good

Slereah

@HDE226868 This might be a religion

0celo7

So I'm not too worried

@HDE226868 I usually don't.

Slereah

and wrong

HDE 226868

23:44

@Slereah How so?

Slereah

Obviously it is supernatural belief :p

0celo7

@Qmechanic is probaby god

HDE 226868

Well, yes, I always thought that Jon Skeet couldn't be an ordinary human.

0celo7

who?

HDE 226868

He must be a god.

0celo7

23:45

is that Qmechanic's real name?

800000 rep

wtf

HDE 226868

479

A: The Many Memes of Meta

Meme: Jon Skeet Originator: Jon Skeet Cultural Height: Every Day. Ever. Background: Jon Skeet is an avid user of Stack Overflow, whose many answers (primarily in c# and .net) have earned him hundreds of thousands of reputation points. This makes him the top-ranked SO user. Related: Jon Skeet ...

Slereah

who has the highest rep here

0celo7

probably @DanielSank

Slereah

Rennie apparently

0celo7

all of his sock puppets

DanielSank

23:47

Heck no. It's @ACuriousMind.

Slereah

I mean PSE

Not this chat

0celo7

$10 Daniel Sank controls @JohnRennie

dmckee

Arrggghhhhhhhh! I shouldn't have to explain that stuff in that much detail to someone who asks that question, damnit!

0celo7

@dmckee has the most rep here

Slereah

what thing

dmckee

23:47

@0celo7 Not compared to John R. The man is a god. Or a sockpuppet.

0celo7

@dmckee link?

ACuriousMind

@0celo7 Not for long! (Just give me another few months)

HDE 226868

@dmckee Was that about physics.stackexchange.com/questions/220066/…?

0celo7

you still didn't tell me why I ~~can't~~ couldn't ping

do you not want to prove random GR things?

dmckee

@HDE226868 Yes. That question is one a grad student should have, so they should be able to follow the answer without every step spelled out in detail.

Slereah

23:49

Hey guys let's do 1D GR

0celo7

@dmckee The book is undergrad level.

Slereah

Is the connection on a 1D manifold always trivial

0celo7

@Slereah ok

no

the circle is curved, obviously

DanielSank

@ACuriousMind Prescribe some conditions you're interested in: maximum population, minimum population, highest production of chocolate, whatever. To get that condition, you might be able to prescribe certain behavioral patterns of the people in the society. Morals are human-digestible notions which encourage those behavioral patterns.

ACuriousMind

@dmckee I feel you. I've had that before - give an answer that should satisfy anyone who knows what the terms in the questions are, only to find out that they actually have no idea what they're doing...

Slereah

23:49

But

Every 1D metric is diffeomorphic to flat space

0celo7

@ACuriousMind hey

Slereah

Remember

dmckee

@0celo7 Only for some pretty special undergrads.

Slereah

On the other hand

0celo7

it's usually because your explanations confuse me

Slereah

23:50

The connection could be non-metric

So I dunno

ACuriousMind

@0celo7 Not you, silly

0celo7

@dmckee the book literally says "for undergraduates" in the front

ACuriousMind

These guys are far worse than you

0celo7

It's on my shelf

@ACuriousMind so wtf is a tensor again

also

Slereah

It is a matrix

Don't you follow Duffield

ACuriousMind

23:51

@DanielSank So you have just now excluded Kantian ethics from your definition of morality :P

0celo7

the book is used by the author in an undergraduate class @ Cambridge

Slereah

Debating on definition is the first sign that the conversation is going nowhere :p

0celo7

^^^^^

like the definition of homogenous space

dmckee

@0celo7 That tells you about the undergrads the author is used to, or hopes for, or selects for. The (very few) courses I had at that level at my undergrad school were all co-numbered with graduate courses. For a reason.

0celo7

@dmckee And yet Shankar wrote his book for grad students at Yale but it's a third year book at my school

things are weird

ACuriousMind

23:54

@DanielSank The assumption alone that it is the outcomes which should dictate morals is a moral position known as consequentialism. A large class of moralities, called deontologist, hold that it is the actions themselves which are moral or immoral, regardless of their actual consequences.

0celo7

they probably don't cover the whole thing

or something

HDE 226868

Oh, didn't that guy ask an astrophysics scattering question earlier?

Slereah

The next step is debating the definition of "definition"

what is even a definition

Assigning meaning to symbols

But what is meaning

dmckee

@ACuriousMind And then there is the position that the reasonable expected outcome is the controling factor. Or you can swirl them all together and wing it.

Slereah

Do we even exist

Do I even exist

0celo7

23:55

yes

Slereah

Is the thing that I call me just a bundle of perceptions

0celo7

otherwise we would not be having this conversation

Slereah

How to differentiate perceptions of the outside world from my own internal processes

Is this distinction meaningful

Can we even prove anything

0celo7

you're insane, that's meaningful

Slereah

But how do I know you exist

All I have are perceptions!

Does time even exist, or are memories just more perceptions

ACuriousMind

23:56

@dmckee Yep. Most humans opt for winging it.

0celo7

@dmckee I understand the answer

am I special?

Slereah

So far I have eaten very few babies winging it

dmckee

@0celo7 You're a precious and unique snowflake. Of course you're special. Just like everyone else.

0celo7

@dmckee bullshit

ACuriousMind

@0celo7 You're not special.

0celo7

23:57

if everyone is special no one is special

ACuriousMind

Man, there's an SMBC for everything :D

0celo7

@ACuriousMind I thought that was going to be a chat post where I said something asinine

ACuriousMind

@Slereah You've never had "baby wings"?

Slereah

Hm, eating baby angels

ACuriousMind

@0celo7 I would not know which one to choose.

Slereah

23:58

@ACuriousMind It has been going on a while

Also a lot of xkcds

0celo7

@ACuriousMind burn

dmckee

@0celo7 So much for my efforts to be that uncle, who always get the kids to believe stupid stuff. Foiled again.

Slereah

Just like Calvin's dad

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