The h Bar

Secret

18:00

i see

0celo7

Now three people have starred it!

bolbteppa

@JohnDuffield I randomly came across your science2020 bio, why did you never learn math despite such an interest in physics? I think I found a fascinating answer to that rotation = composition of reflections spin question I asked you about, fascinating stuff

@0celo7 physicists can usually solve quadratic equations...

0celo7

Four people? Seriously

There are four astronomers, great.

ACuriousMind

18:16

It seems you should not provoke THE ASTRONOMER by talking about stars :P

0celo7

$\mathfrak{The\,\,Astronomer}$ is evil.

ACuriousMind

Interesting, why does that look so weird, e.g. why is the $\mathfrak{n}$ raised above the baseline?

0celo7

Pic?

Looks fine on my screen.

ACuriousMind

0celo7

waaaaat

ACuriousMind

18:19

lol

0celo7

something's wrong with your TeX :p

you should get that checked out

HDE 226868

@0celo7 Dunno, I see the same as ACM.

DanielSank

@0celo7 Are we playing the post-mathjax-macros-to-screw-up-everyone's-rendering game?

I love that game.

0celo7

@HDE226868 You're Canadian

Danu

13

A: Proving Kepler's 1st Law without differential equations

Newton's original proof was in fact based on geometry (he hadn't invented calculus yet). Richard Feynman devised his own, simpler geometric proof for one of his famous lectures. You can find it in Feynman's Lost Lecture, by Goodstein & Goodstein, and in this article: Paths of the Planets from Hall &

this deserves more attention

HDE 226868

18:20

@0celo7 Again, nope.

0celo7

@DanielSank No?

@DanielSank never played it

ACuriousMind

@HDE226868: Which operating system are you on?

DanielSank

@Danu Whenever I read stuff like that I feel like it's just broke-ass calculus.

ACuriousMind

^

HDE 226868

@ACuriousMind Windows 7.

What about you?

Danu

18:22

@DanielSank 0/10

ACuriousMind

@HDE226868 Same. Probably to do with the installed fonts, then

Danu

I can appreciate some good ol' Euclidean geometry

0celo7

I'm on Yosemite ATM

brb switching to Win8.1

Danu

The question isn't amazing, but the answer is.

DanielSank

@Danu Yeah, but then people start making these infinitesimal constructions with limiting procedures.

At that point, just do the calculus and move on?

ACuriousMind

18:22

@Danu Geometry as done by Euclid is not what we call "Euclidean geometry" :P

DanielSank

@Danu I mean, those constructions are essential for teaching calculus, don't get me wrong.

0celo7

Danu

@ACuriousMind lol

@DanielSank No they're not :P

DanielSank

@0celo7 Why are we posting pictures of words?

@Danu ?

Danu

Oh you mean the general ting

the infinitesimal constructions with limiting

I thought you meant this particular ellipse thing

DanielSank

18:24

@Danu Yes.

@Danu That would be a ridiculous statement.

Danu

@DanielSank Hence my reaction

HDE 226868

@DanielSank There are some differences in what people's computers are rendering for that word.

ACuriousMind

@DanielSank I complained about $\mathfrak{The Astronomer}$ looking weird on my screen (e.g. the 'n' sticking out). Now we're looking for the reason it looks that way to me but originally not to 0celo7

DanielSank

@HDE226868 Can I play too?

0celo7

@DanielSank You're welcome

Danu

18:25

That's the ugliest capital letter "a" I've ever seen.

DanielSank

@0celo7 How do I play?

ACuriousMind

I think we can fairly resonably conclude that it has to do with different font installations on Windows compared to OSX.

Danu

@ACuriousMind It looks like that to me, too.

0celo7

@DanielSank render the word and take a picture

DanielSank

@Danu That's an "a"?

Danu

18:26

(Windows)

DanielSank

I thought it said "The Ustronomer"

0celo7

@ACuriousMind My second picture is on Windows!

Danu

@DanielSank Yeah, "zoom out" a bit

(squint)

DanielSank

@0celo7 How to render?

Danu

"Start ChatJax"

0celo7

18:26

uh, chatjax?

Slereah

hey

ACuriousMind

@0celo7 Yes, and the 'n' is sticking out.

0celo7

@ACuriousMind Not as severely, if I see correctly

ACuriousMind

@0celo7 That'd be the difference between Win7 and Win8, then

DanielSank

Oh, we're rendering it via chatjax? I thought you meant via a local TeX compiler.

ACuriousMind

18:27

Also, your picture is larger, it's hard to tell

0celo7

@ACuriousMind 1800p master race

DanielSank

Why is the "n" a little above the other letters?

0celo7

@DanielSank that's the question

@DanielSank you can do that too!

Danu

@DanielSank You a bit slow tonight? :D

DanielSank

@Danu That was a joke, dude.

0celo7

18:29

DanielSank

@0celo7 Now it's flat.

0celo7

From TeXShop

DanielSank

You know, there is a TeX Stack Exchange...

ACuriousMind

Yeah, TeX does it correctly, it seems this is a MathJaX issue

DanielSank

How do I get mathfrak?

ACuriousMind

18:30

@DanielSank What do you mean?

0celo7

I don't think \mathfrak is in default TeX

DanielSank

@0celo7 It's not.

0celo7

It wasn't in mine, I had to get a package.

Dunno which one

DanielSank

Apparently it's amssymb.

ACuriousMind

Try using the package amsmath

BTW, looks that odd way to me when I type it in an answer on the site, too, so it's not an issue with chat

DanielSank

18:31

Anyway, on my system (Ubuntu, TeX installed via texlive package), the n is where it should be.

0celo7

\usepackage{amsmath, amssymb, amsthm, yfonts, esint, fancyvrb, mathrsfs, tikz-cd, graphicx, bbm, physics}

It's one of those

DanielSank

It's amssymb.

What is physics?

0celo7

@DanielSank Unrigorous

ACuriousMind

Provides bras, kets and stuff

Leuchte

@DanielSank What is meaning life?

NeuroFuzzy

18:33

Fizks

Leuchte

skziF

0celo7

bbm?

ACuriousMind

Haddaway - What Is Love

►

DanielSank

@Leuchte A process which self-replicates and reduces local entropy?

0celo7

I have no clue what my packages do

ACuriousMind

18:33

@0celo7 I was just about to ask what esint is :P

0celo7

::eye twich::

ACuriousMind

@0celo7 lolwat? I found something that's blocked for you but not for me? :D

Mats Granvik

I just disproved Galileo's observation about falling bodies and their equal velocities.
You see, if you take a transparent shampoo bottle and turn it back and forth upside down you will find that a large air bubble rises much faster than a small bubble.

DanielSank

@ACuriousMind That's blocked for me too.

Danu

@MatsGranvik lol :D

Leuchte

18:34

@MatsGranvik Isn't that a rising body though?

:D

Danu

p-p-p-proxxxxy

0celo7

@DanielSank We are in the same country you know...

ACuriousMind

@DanielSank Then neither of you will get to know what love is...

Leuchte

or are we...

0celo7

You might think TN is full of hicks but we're just as American as you ;)

Mats Granvik

18:35

@Leuchte Yes but the amount of shampoo is constant.

and it falls

DanielSank

@ACuriousMind Nooooooooooo

0celo7

@ACuriousMind No idea!

ctan.org/pkg/esint?lang=en

Ah, multiple integrals.

And it makes the loop on the closed line integral larger.

DanielSank

@dmckee: with respect to your bountied question:

ACuriousMind

I never use these silly triple or loop integral signs

0celo7

@ACuriousMind I don't either

DanielSank

18:39

I see two different approaches. Frequently with circuit analysis the student is puzzled because he/she does not understand how to think about a linear response system.

0celo7

I just like the bigger o on the \oint

Wait you said "loop"

Well screw you

DanielSank

A possible answer could assume that Ohm's law is correct and then carefully explain why that law applied to each individual resistor results in shared voltage.

However, you may want a more physical approach wherein we start with basic physics such as the force on a charged particle from an electric field.

0celo7

@ACuriousMind What packages do you run?

DanielSank

If we start there, the standard course would be to derive Ohm's law, and then go back to the first approach.

Let me know what you have in mind and maybe I'll write it up.

0celo7

@ACuriousMind It spaces measures properly :)

Danu

18:42

@ACuriousMind How do you indicate loop integrals, then?

ACuriousMind

@0celo7 Those I need. Only ones I always use are hyperref, xparse and xcolor

DanielSank

@Danu Why bother changing the integration sign at all?

ACuriousMind

@Danu Uh, by having $\gamma$ be a loop and writing $\int_\gamma$?

0celo7

@ACuriousMind How do you get frak?

DanielSank

@ACuriousMind +1

0celo7

18:43

Wish I could -1 in chat

ACuriousMind

@0celo7 From amssymb. But not everything I write needs mathfrak

0celo7

@ACuriousMind Wait you assemble packages differently for each doc?

ACuriousMind

@0celo7 Yes.

DanielSank

@ACuriousMind Weird.

0celo7

Why?

ACuriousMind

18:44

Why would I want to load something I don't need?

DanielSank

@ACuriousMind Laziness.

0celo7

^

DanielSank

Although note that this is quite different from the usual notion of "lazy loading" :D

0celo7

Does the load even take a noticeable amount of time?

DanielSank

I crack myself up.

ACuriousMind

18:45

Also, the more packages, the greater the danger something might conflict among them

@DanielSank lol

0celo7

@DanielSank I didn't get it

DanielSank

@0celo7 Computer joke.

ACuriousMind

@0celo7 It's a CS term

0celo7

@ACuriousMind I figured, but why do you know about it

Your realm of knowledge never ceases to amaze me

DanielSank

@0celo7 Because knowing how to computer is really really useful?

ACuriousMind

18:48

While I'm not doing it much anymore, I like programming.

0celo7

@DanielSank I'm an engineer, I have to learn how to computer

@ACuriousMind I think it's like pulling teeth, but to each their own.

ACuriousMind

@0celo7 Your own or someone else's teeth? :D

DanielSank

@0celo7 >:(

@ACuriousMind eewwwwwwww

0celo7

@ACuriousMind Tie my tooth to someone else's and run at full speed away.

DanielSank

@0celo7 gross

0celo7

18:50

@DanielSank What?

@DanielSank no u

DanielSank

@0celo7 Programming is super fun and really useful!

@0celo7 wat?

0celo7

@DanielSank Hell no, agree.

DanielSank

@0celo7 I do not understand that sentence at all.

0celo7

Sewers are also really useful. Not so much fun.

@DanielSank you're a wat

@DanielSank "Hell no" to the first part, "agree" to the second part.

DanielSank

@0celo7 I see.

@0celo7 How come you're always talking about diffeo geo if you're an engineer?

0celo7

18:55

@DanielSank It's interesting

DanielSank

@0celo7 But not career material for you?

0celo7

@DanielSank God no

DanielSank

@0celo7 I see.

0celo7

I'm also a math major you know

DanielSank

That's how I feel about math.

0celo7

18:55

I think people forget this

DanielSank

@0celo7 Hard to forget what you never knew.

Danu

@ACuriousMind That costs more words :P

0celo7

@DanielSank Hmm, it says it right in my profile.

Danu

@0celo7 Duh

0celo7

@Danu Seriously?

DanielSank

18:56

@Danu I don't do that.

@0celo7 Not sure I ever read your profile.

Danu

Custom preambles all the way

Maybe you guys don't use a lot of packages

I use like 30+ in most documents, don't want all possible combinations in there

0celo7

@DanielSank I read everyone's if I talk to them. Maybe I'm strange.

DanielSank

@Danu I use maybe eight.

@Danu Woah.

0celo7

@Danu Holy crap

dmckee

@DanielSank In my ideal world we'd have (at least) one of each, and I'll take my guide in deciding the bounty from the voting.

I did a hand-wavy version of the microscopic model, without explaining the connection to Ohm's law, because my sense was that both posters (the sandwich model guy and yesterday's poster) wanted a intuitive feel rather than a careful explanation of math.

DanielSank

18:58

@Danu I have seven in my "always use this" preamble.

dmckee

I think the method assuming Ohm's law has the advantage of clear sequence, however; rather like a mathematical proof. And would appeal more to the nominal audience of the site.

Danu

@DanielSank Welp... :P

DanielSank

@dmckee I see. Indeed, deriving Ohm's law via the e.g. Drude model seems out of place there.

Danu

I don't see how you can use so few packages

DanielSank

In fact, I think I did this in chat with @0celo7 not so long ago...

@Danu amsmath, amstext, amssymb, graphicx, import, appendix

0celo7

19:01

You did. I didn't understand any of it.

DanielSank

The rest I define myself in a macros.tex file that I always \input.

Danu

amssymb, amsmath, amsthm, mathtools, enumerate, graphicx, tikz all absolutely mandatory :P

0celo7

At least, I wasn't convinced we had derived Ohm.

mathtools?

Danu

amsfonts

subcaption

hyperref!!

those are just the minimal things :P

oh yeah.. geometry for margins

DanielSank

@Danu I do margins in my class files.

Danu

19:03

I like this idea of splitting packages and macros

Maybe I'll start doing that next semester

my preamble is getting too long

0celo7

Pic?

Danu

It doesn't fit on a single screen unless I zoom out a lot

DanielSank

@Danu I try to respect the fact that TeX is a typsetting language. The fact that it's a programming language is a somewhat sad accident which has been abused up the wazoo.

Danu

@DanielSank meh

DanielSank

@Danu Nah, dude, this is not a "meh". Doing any kind of modularity management in TeX is really a pain in the butt.

Even sensible equation referencing is nigh impossible out of the box.

Danu

19:05

@DanielSank I don't really need modularity---but I understand that it's your thing

@DanielSank ? why that

DanielSank

@Danu You may want it when you write your dissertation.

Danu

@DanielSank Might

DanielSank

@Danu Suppose I write a personal note for myself. Then six months later I want to incorporate it into a book I'm writing.

How the crap do I manage name collisions on \label'd things?

Danu

@DanielSank Copy + paste the text

@DanielSank Be careful about the labeling

DanielSank

...

Danu

19:06

but I see what you mean

I don't number many of my equations so it's not an issue for me

DanielSank

Either you're joking or you've never worked on a large document or software project.

Danu

but I know that most people do

never worked on a software project, always stuck to sub-100 page documents so far.

DanielSank

"Be careful about labeling" is the road to hell.

0celo7

What is the shortest dissertation on record?

DanielSank

I need to write/find a package which can prepend labels with the full path of the object, i.e. the chapter/section/subsection.

Danu

19:07

26

Q: What is the shortest Ph.D. thesis?

The question is self-explanatory, but I want to make some remarks in order to prevent the responses from going off into undesirable directions. It seems that every few years I hear someone ask this question; it seems to hold a perennial fascination for research mathematicians, just as quests for...

DanielSank

@0celo7 I think it might be DeBroglie.

Danu

3 pages of content

0celo7

Wow. 3 good pages?

DanielSank

Anyway, @Danu, I see documentation somewhat similarly to how I see computer code: you want to re-use fragments to maintain consistency and reduce work.

This is why we reference papers instead of rewriting them every time we need a result.

Danu

@DanielSank That's a ridiculous analogy :P

DanielSank

19:12

@Danu I disagree, obviously.

Danu

@DanielSank So how'd you solve the equation referencing thing

DanielSank

@Danu Haven't yet.

My stop-gap solution is to use the full path of the labeled object in the \label macro.

ACuriousMind

@Danu You should not be putting in equation tags by hand, anyway

DanielSank

@ACuriousMind Howzat?

0celo7

@ACuriousMind What do you mean?

Danu

19:12

@ACuriousMind ?

That sounds rather ridiculous

ACuriousMind

Okay, one step backwards: What exactly do you mean by "equation referencing thing"?

Either I've misunderstood you or you've misunderstood me :P

DanielSank

I'm just gunna leave this here.

Danu

^still don't know how git works

DanielSank

@Danu Can still browse files.

0celo7

> \levelstay{Introduction}

This is a book about quantum computing.

\leveldown{Sub-introduction}

Quantum computing is cool.

\levelstay{Sub-introduction II}

No really, it's super cool.

Haha

DanielSank

19:15

^ ?

0celo7

@ACuriousMind Uh, by having $\gamma$ be a loop and writing $\oint$?

Less work.

And if there's only one loop there's no ambiguity.

Danu

O-Zone - Dragostea din tei

►

DanielSank

The chat room just got weird.

0celo7

@Danu What?

Danu

Spread MAXIMUM confusion! :D

DanielSank

19:18

@0celo7 Your comment about loop integrals came at a confusing time, and was marked as a response to another message in a way that doesn't make sense to me. Then @Danu posted more weirdness.

0celo7

It this now a music thread?

Danu

@0celo7 Don't post your "music" please ;)

Alex C Du hast den schönsten Arsch der welt

►

^German weirdness

DanielSank

I can't resist. This is my favorite piece of music ever written

Nostalgias - Orlando Marconi & Juanjo Dominguez

►

0celo7

Jay Z feat Mr. Hudson - Young Forever Official Video Lyrics

►

@Danu YES

I remember this!

Danu

@DanielSank That's a very strong statement.

DanielSank

19:20

@Danu It's also true.

0celo7

@DanielSank Wow, terrible taste in music I'm afraid.

DanielSank

@0celo7 :(

0celo7

@Danu Thanks for that song!

Danu

@0celo7 Says the hardcore guy :P

0celo7

@Danu I listen to a lot more than hardcore.

Danu

19:21

@DanielSank I think it's likeable---but not that special. It just doesn't do anything that really really stands out

0celo7

The only reason I'd move to Dutchland is for the dance music.

DanielSank

@Danu I listen to a lot of guitar and a lot of tango. This piece is special in several ways. Doesn't mean you have to like it.

0celo7

I think German music sounds strange.

Danu

Sexy song:

Janis Joplin - Summertime (Live -1969)

►

DanielSank

The melody is traded between the two instruments so smoothly that you don't even notice unless you really pay attention.

Danu

19:22

(although I like the album version slightly better)

DanielSank

It is difficult at times to really say which instrument is carrying the melody.

Danu

@DanielSank Yeah, but favorite piece ever is just too strong :P

0celo7

CA$H OUT - She Twerkin

►

Danu

Though I think it's too strong a statement for any piece of music

@0celo7 I hope you're joking :P

DanielSank

@Danu You have decided that people cannot have favorites? Who the hell are you, God?

0celo7

19:23

@Danu About?

Danu

@DanielSank Definitely

0celo7

A completely different flavor:

Chris One - Sin City (Phuture Noize Remix) [HQ/HD]

►

Danu

Haven't you noticed that I'm omnipotent, by now?

DanielSank

@Danu I see. Well I suppose I ought to apologize for past insults, etc. etc.

0celo7

@Danu The mod power has gone to his head!

Danu

19:24

@0celo7 Ah, you're in this phase

DanielSank

But seriously, piss off. I think I know my favorites better than you do @Danu.

0celo7

@Danu Phase?

Danu

@DanielSank No need, I could see you didn't mean it

0celo7

I like most hard dance.

Danu

@DanielSank Ai, did I anger you?

0celo7

19:25

It can be soft or really hard.

DanielSank

@Danu No.

0celo7

Coone & Jim Ferren - 150 BPM (Global Dedication) [HQ Original]

►

Danu

@DanielSank Then piss off is a bit strong, don't you think?

0celo7

Is this also "phase" music?

DanielSank

@Danu Uh, I don't know. Is it strong? In my head it's a silly phrase with almost no meaning since nobody in the US ever uses it.

Danu

19:26

@0celo7 For a younger me, it was

@DanielSank It's so non-standard that one only uses it when serious.

(typically)

I'm sure you've noticed that people that are really angry don't tend to go for the standard insults

0celo7

I listen to a sufficiently broad amount of music that I don't think it's very phase-y.

DanielSank

@Danu Oh. I mean, I don't think I've ever heard it said in real life.

Danu

@0celo7 Time will tell :)

DanielSank

In British movies it's used between people who are sort of mildly annoyed at their friends... I think.

Danu

But you're not British

DanielSank

19:28

@Danu Correct.

0celo7

@Danu Maybe. Wonder what I'll like ten years from now.

Hopefully not that dreadful "rock" thing.

Danu

In 2-3 years it'll already be very different---if my experience is any kind of guide

0celo7

Hmm, how long did your "phase" last?

DanielSank

@0celo7 Don't listen to him.

0celo7

And I don't listen to that much hardcore. The production quality of 90% of hardcore is abysmal.

DanielSank

19:30

I had a "phase" starting when I was 14 that hasn't ended yet.

If you like music you like it.

0celo7

I think I've listened to the same type of music for the last 4 years.

At least since BF3 came out. A guy on Symthic posted a Frontlinear song and I've been hooked ever since.

@Danu I just put on a hardcore album, thanks for the suggestion.

DanielSank

What does "hardcore" mean to you guys?

Metal?

0celo7

Hellsystem & Dj D - Daylight (Hellsystem Remix)

►

^ song that's on right now

Danu

@DanielSank Right, and your experience is likely to be a better guide because [citation needed]

0celo7

Best part about Dutchland

Danu

19:37

@DanielSank Definitely not true in my opinion.

@DanielSank It's a type of electronic music

Hardcore (electronic dance music genre)

Hardcore, formerly called hardcore techno, is a subgenre of electronic dance music originating in Europe from the emergent raves in the 1990s. It was initially designed at Rotterdam in Netherlands, derived from techno. Its subgenres are usually distinct from other electronic dance music genres by its faster tempos (160 to 200 BPM or more), the intensity of the kicks and the synthesized bass (in some subgenres), the rhythm and the atmosphere of the themes (sometimes violent), the usage of saturation and experimentation close to industrial dance music. == HistoryEdit == === EmergenceEdit ...

DanielSank

@Danu My baseless assertions are as valid as yours.

3

Danu

@DanielSank Yeah, so don't try selling them as more valid :D

DanielSank

@Danu Why not?

Danu

Right, fine, be like that ;)

DanielSank

@Danu Will do, thanks.

0celo7

19:39

@Danu I think most of my music is just hardstyle of rawstyle.

Angerfist - Fuck The Promqueen HQ

►

I'm definitely not into that.

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