The h Bar

DanielSank

00:04

@0celo7 I made comments.

I'm down with it until you get to "Physicist's Definition of a Tensor".

At that point the whole thing gets really hard to understand.

I explained why.

0celo7

@DanielSank well because I haven't edited that yet??

the comments you left on that section the first time around are still there

DanielSank

00:26

@0celo7 Don't know what you're talking about.

I had not previously left comments, I don't think.

0celo7

wrong

see the last page

0celo7

01:01

@all If someone says they/their family is "not wealthy", pls ballpark yearly income.

user54412

@FenderLesPaul really??

Mike Miller

yes

0celo7

01:20

@ACuriousMind he remembered!!

let's see how screwed I am...

.-.

oh god I don't get any of this

ACuriousMind

Well, it'd be suspicious if you understood the paper after reading it once :P

(Or a sign of a really good writer)

0celo7

it's a report on radiation tolerance in complex oxides

wtf are these words

ACuriousMind

Oh gosh that sounds fascinating

/s

0celo7

ikr

/sssssssss

wtf

I wanted to learn more about crystals under extreme conditions, not chemistry

there's not even any math in this paper

ACuriousMind

lol

0celo7

01:27

@ACuriousMind I take it you can't help here :P

ACuriousMind

Yeah, I don't think so

0celo7

> In pyrochlores, the cation antisite is the lowest energy intrinsic disorder mechanism

Proof?

ACuriousMind

For all I know, that could've been generated by one of those paper generators :P

0celo7

that's what they call grad students in Germany now?

ACuriousMind

Haha

I meant those programs that generate "papers" by stringing together technical terms into grammatically correct, but non-sensical statements. Like snarXiv.

0celo7

01:32

@ACuriousMind the prof called one of the undergrads "the girl for everything" (ein Madchen fur alles) and all the non-German speaking people thought he called the guy a slut :D

no_choice99

are these programs good to get a latex template for an article or thesis?

ACuriousMind

@0celo7 xDDDD

0celo7

his Germanisms are amazing

he once said "a chicken who is blind might find corn"

ACuriousMind

It is quite hard to avoid those when speaking freely

0celo7

@ACuriousMind he also proposed to have the group meetings in a bar, but he was reminded of our barbaric drinking laws

apparently that's not uncommon in Germany

ACuriousMind

01:40

@0celo7 Depends on the people, but it happens

I wouldn't say it's exactly "common" though

0celo7

@ACuriousMind maybe the experimentalists are more fun than you blod theorists

ACuriousMind

@0celo7 Hehe, nah, I can say that at least some of them are quite trinkfest (uh...is there even an English word for this?)

0celo7

I'm not sure what that means in the lingua antiquia

Sie trinken viel?

ACuriousMind

Apparently it means one can hold one's liquor.

0celo7

that means you can drink a lot

(and not get wasted)

@ACuriousMind explain what it means to you in German

ACuriousMind

01:47

@0celo7 Well, it means you can drink a lot, but it also has a strong subtext that you like to drink.

Although I guess it is technically possible to be trinkfest and dislike alcohol

0celo7

I'm a good child and I've never been around alcohol so I wouldn't know about the American version

@ACuriousMind does snarXiv generate new papers with every click?

ACuriousMind

I have no idea how it works internally

0celo7

these are amazing

ACuriousMind

Maybe it just has a giant stash of those and cycles them through

0celo7

if they're randomly generated...huge props

ACuriousMind

01:51

@0celo7 They are definitely randomly generated

0celo7

wtf does $Fd\bar 3m$ mean??

ACuriousMind

Probably nothing :D

Perhaps it's some weird name for some weird manifold, though

0celo7

my paper says Pyrochlore $(Fd\bar 3m)$

I know what pyrochlore is

ACuriousMind

Oh, you didn't get that from a snarXiv paper :D

0celo7

it might be the name for the symmetry group of the crystal

> Many simple oxides such as magnesia
(MgO) and alumina (Al2O3) are susceptible
to void swelling (5).

ffs I have to go on a literature hunt

ACuriousMind

01:54

@0celo7 Well...what did you expect. That is what happens when one reads papers :P

0celo7

I'll just take experimental facts for granted

no use hunting down the proofs

wait, what even is void swelling??

ACuriousMind

A weird name for the expansion of the universe?

Bernard Meurer

A bad porn category?

0celo7

@ACuriousMind Oh, my prof showed that $\operatorname{End}V$ is not isomorphic to $V^*\otimes V$ for a general vector space

the proof used functional analysis

in particular, he claimed there was no way to define the identity as an element of $V^*\otimes V$

ACuriousMind

@0celo7 You'll want to be careful here - what even is the tensor product of infinite-dimensional spaces. Abstractly, I think they are isomorphic as vector spaces because they have the same cardinality. But they're probably not isomorphic if they're Banach spaces (and the tensor product is then not the algebraic tensor product)

0celo7

02:00

Well, he wasn't exactly clear on that either. Apparently he's not an algebraic topologist. He works in PDE, does stuff with "spectral" in the name and has 20 alg.top books

I just made the leap of logic

ACuriousMind

Alternatively, he also could've shown that there is no canonical isomorphism.

0celo7

@ACuriousMind Honestly, I don't know exactly what he showed.

It was way over my head.

I think we were worried about completely different things.

ACuriousMind

Hmm, yes, probably he showed that the map $V^\ast\otimes V\to\mathrm{End}(V), f\otimes v\mapsto (w\mapsto f(w)v)$ is not an isomorphism in the infinite-dimensional case (and it is this isomorphism I use to define the trace of an endomorphism through the tensor product)

0celo7

@ACuriousMind He claimed the map $V^*\otimes V\to\operatorname{End}V$ failed surjectivity

ACuriousMind

Now I wonder whether possibly the trace-class operators are exactly the image of that map.

0celo7

02:04

he also said something about free products and $\bigoplus_n\mathbb{R}\ne \times_n\mathbb{R}$

I was very confused

@ACuriousMind Ok well even I know that the identity is not trace class

ACuriousMind

@0celo7 Ah, yes, infinite products are not the same as infinite coproducts. Not sure why he said that, though

0celo7

@ACuriousMind ::shrug::

ACuriousMind

(It's bad style to use $\oplus$ for the coproduct when it's not the biproduct, though :P)

0celo7

@ACuriousMind He then said something about categories

ACuriousMind

Haha, I like this guy already ;)

0celo7

02:06

He's a UH grad

but I've told you that 10000 times, right?

ACuriousMind

Yes

but, believe it or not, there are people here I don't like

0celo7

he's a UH grad

say, did you know that he's a UH grad?

would you believe that he's a UH grad!?

Mike Miller

@ACuriousMind It's bad style to use notation that might confuse others. Denoting the infinite direct sum of vector spaces by $\oplus$ will confuse no-one; denoting it with $\coprod$ will confuse most.

ACuriousMind

@MikeMiller I always have trouble remembering whether the infinite $\oplus$ is supposed to be the product or the coproduct, but that might just be me, then

0celo7

@ACuriousMind what's the German word for "modules"

ACuriousMind

02:11

@0celo7 Modul.

stressed on the first syllable

Mike Miller

Really? Interesting.

0celo7

plural!

ACuriousMind

@0celo7 Moduln

0celo7

hmm

Mike Miller

Might just be artifacts of our education. I feel as though if I showed those two symbols to grad students here I would get the responses I expected above the vast majority of the time.

0celo7

02:11

I swear he said "moduli"

ACuriousMind

@0celo7 Nah, Moduli are, well, moduli.

0celo7

I know, but when I asked him what that was (I don't remember the definition of moduli), he told me what a module is

ACuriousMind

@MikeMiller Well, I think most math people I know would be fine with either way

@0celo7 I don't think the definition of "moduli" is any narrower than "something which modulates some structure" in general

Mike Miller

Anyone without a familiarity with the notation of category theorists (a good chunk of people here...) would be confused by the coproduct symbol; at best I think most people see it in the context of spaces.

0celo7

@ACuriousMind as in "vector space but scalars in a ring"

I misread, ignore that.

ACuriousMind

02:14

@0celo7 I know what modules are ;)

0celo7

@ACuriousMind What part of ignore don't you get

Bernard Meurer

I find it funny when you guy's refer to mathematicians as 'people'. Well known fact that they're here to take over

0celo7

Those guys couldn't take over a broom closet

They'd be too worried about the symmetry groups of the cobwebs

ACuriousMind

...why would anyone want to take over a broom closet?

0celo7

TO STEAL BROOMS

see^

No vision.

Bernard Meurer

02:15

Hahahaha @0celo7 you're probably right

ACuriousMind

What would a mathematician do with a broom?

Bernard Meurer

@ACuriousMind Fly away to his family?

0celo7

@ACuriousMind do some real work for once

I did overhear someone today "physicists are a cantankerous bunch"

ACuriousMind

::looks up cantankerous::

Huh.

0celo7

it must have been either math, chem or engineering faculty

ACuriousMind

02:18

Well, I guess you can get the impression if you go to physics colloquia and seminars (at least here, the questions tend to be...aggressive)

0celo7

Lumo is cantankerous

Bernard Meurer

My questions are agressive. Agressively dumb

0celo7

can confirm

Secret

@user36790 you are right that given some time dependent expression that describe the physics $v(t) \rightarrow v(-t)$ and that $v(-t)=-v(t)$ when time reversal symmetry is obeyed

The issue is that I am not sure what equations will describe the numbering of the frames. 50 40 30 20 10, thus I am not sure how to apply $t\rigtharrow -t$ in this case

Anyone else can help him out?

ACuriousMind

@Secret I have an answer written up for that, but he deleted his question before I could submit it.

@0celo7 That's not wrong.

0celo7

02:22

oh so now you're an expert on the word

you should do my lit readings

ACuriousMind

@0celo7 I am able to process a dictionary entry in less than a minute, yes :P

0celo7

@ACuriousMind well I'm so sorry, we can't all have IQs greater than 150

Bernard Meurer

It's pretty easy if you go so low you break the IQ variable and come back on top

ACuriousMind

@0celo7 Trivially true, because 100 has to be the median/mean/whatever "mid" they take

Also, I have no idea what my IQ is, and no particular desire to find out

0celo7

average IQ is rising, I don't think it's being adjusted

@ACuriousMind >150

only Einstein, Hawking, Lumo, etc. can process definitions that quickly

you're among the greats

Bernard Meurer

02:24

IQ is just snake oil

but with numbers on it and pretty images on the test

ACuriousMind

@0celo7 It's rising based on the "outdated tests". Each "new" test is devised such that the median is 100 for an "average" sample of a population, whatever that means

@BernardMeurer Well, it accurately measures your ability to take an IQ test :P

Bernard Meurer

@ACuriousMind Which doesn't really imply any practical use tho

ACuriousMind

But it also seems to be a surprisingly good predictor for various things one also associates with intelligence and success, so whatever it is, it is not arbitary

0celo7

IQ is very well correlated with many measures of life success.

Bernard Meurer

Definitely not arbitrary

I'm just bitching about IQ because mine is low

0celo7

02:27

Or maybe just the one that matters

"income"

@BernardMeurer what is it

unless it's below 140 there's still hope

Bernard Meurer

119

0celo7

(mine is below that)

Bernard Meurer

or 114 I don't recall it's been a while

0celo7

114 backwards is 411 which is 9 away from 420

ACuriousMind

mind=blown ::hits blunt::

Bernard Meurer

02:29

You're the best psychologist @0celo7, I feel better already

ACuriousMind

Why did you feel bad?

Secret

My IQ is measured to be 145, but effectively my IQ is around 100 because of things like forgetfulness, low SQ and EQ causing me to unable to function my IQ abilities most of the time

ACuriousMind

Is it usual for people to take IQ tests where you all live or is it coincidence that I seem to be the only chatter right now who hasn't taken one?

Bernard Meurer

@ACuriousMind My testing skills in general are hideous and that constantly pisses me off because a lot is based on tests

Secret

People in our era usually have IQ test taken as part of some routine body check when we are just babies

ACuriousMind

02:37

@0celo7 I hope your recurring "I'm not smart" episodes are not based on that :P

0celo7

My skills in general are hideous

ACuriousMind

@Secret Uhhhh...how can you make a baby take an IQ test? oO

They can't hold the pencil!

0celo7

They can blink the correct answer.

ACuriousMind

@0celo7 Well...any baby that does that is off the IQ scale anyway, I think :D

Secret

Then I think I should be saying at least primary school, cause that roughly when I have my IQ measured

I only rememebr I was very littel when I took my IQ test as part of a body check o assessment in a clincic

0celo7

02:39

@ACuriousMind No, it's probably a result of having a hardass father who I never felt really loved me

Bernard Meurer

I got tested last year amidst my senior year for mysterious reasons

0celo7

But that's not so funny as me sucking at analysis, is it?

Bernard Meurer

the principal just called me in, tested and that was it

Mike Miller

@ACuriousMind Yes, and both correlate reasonably well to your family's wealth...

0celo7

Also I suck at analysis.

@MikeMiller Smart people tend to be more wealthy. I don't know why this should surprise anyone.

ACuriousMind

02:40

@BernardMeurer oO

@0celo7 :| I don't find it funny that you (think you) suck at analysis, either.

Bernard Meurer

@ACuriousMind Yeah I still wonder whether he thought I was really smart or really dumb at first

ACuriousMind

@BernardMeurer You didn't ask him why?

Or did he refuse to answer?

Perhaps you narrowly evaded a secret government program that harvests the smartest minds of the next generation

Bernard Meurer

@ACuriousMind Hell me? I don't ask someone who's a superior his motives unless I'm looking for some whooping

It's Brazil @ACuriousMind we harvest the minds with the largest booties for the programs

ACuriousMind

@0celo7 You could also see it the other way - wealthy people can afford a lifestyle that tends to make you smarter

Jan 18 at 18:20, by ACuriousMind

Note to self: Don't go to Brazil.

0celo7

@ACuriousMind I think regression towards the mean is present in all populations though

Bernard Meurer

02:46

@ACuriousMind As I saw written somewhere in Germany when i visited last year "The best minds one hangs"

0celo7

@ACuriousMind apparently not Chinese babies!

ACuriousMind

@BernardMeurer Never heard that expression. Some googling shows me you probably saw the title of a book that's called that.

Bernard Meurer

@ACuriousMind It was in the checkpoint charlie museum

I have a pic, wait a second

user116211

@ACuriousMind: Hi! Well, I've undeleted it: physics.stackexchange.com/questions/231740/… . Would you answer that now?

ACuriousMind

@user36790 Done ;)

user116211

02:57

@ACuriousMind: You seemed to be faster than the only fastest man alive: Barry Allen:P Thanks for your help; I would read it now.

0celo7

Barry Allen sucks.

ACuriousMind

@BernardMeurer Ah, yes. Interestingly, the German version uses the archaic henkt instead of hängt, of which I'm not sure if it should really be translated with "hangs", since a Henker is more a general executioner (although it surely derives from him hanging people)

user116211

@0celo7: You don't like Flash?

0celo7

@user36790 I like the doctor better.

ACuriousMind

@user36790 Well, I'd already written it, I just had to click "post your answer"

Secret

02:59

Ah I see, so that's how velocity got a minus sign when t reversed

and that's where I got wrong when I am tring to explained to user36790

Bernard Meurer

@ACuriousMind It does sound more poetic with hängt though; to my ears at least

ACuriousMind

@BernardMeurer Well, henkt and hängt sound almost the same - most people will not be able to reliably tell which one someone is trying to say

Particularly if they come from a region where the difference between g and k is non-existent

Bernard Meurer

@ACuriousMind sound was bad choice of words, I didn't mean phonetically but rather in meaning

ACuriousMind

Oh. Well, I somehow also prefer the hängt

But probably only because henken is such an unusual word

Bernard Meurer

@ACuriousMind You're lucky I only met you recently, I'd have explored you so much with German questions while studying last year

Or tried to at least

ACuriousMind

03:07

Haha, well, you'd not be the first, @0celo7 asks such questions from time to time, too

Secret

lol I am going to just focus on get my head around quantum first

0celo7

wtf is henkt

Bernard Meurer

@0celo7 It's a kind of chicken

ACuriousMind

@0celo7 A form of henken, which is in turn an archaic form of hängen

user116211

@0celo7: You would surely like tomorrow's episode where Reverse Flash gets resurrected again (from nowhere:/)

user116211

03:11

Eobard Thawne is back.

0celo7

I haven't watched any TV since getting to college.

:(

I think I last saw when the doctor (can't remember his name!) was sent back

or something like that

it's been a while

user116211

@0celo7: Neither do I. I download these. Are you talking about S1?

0celo7

I...don't know.

I'm saying I haven't watched any TV series

regardless of the medium

user116211

@0celo7: Doctor...hmm; WTF; I can't even guess what you wanted to say:(

FenderLesPaul

@ChrisWhite really what?

0celo7

03:15

@user36790 The guy who runs the accelerator

Reverse Flash, Eobard Thawne

that guy

ACuriousMind

@FenderLesPaul That the two Baez are cousins

FenderLesPaul

oh

yeah they are

user116211

@0celo7: You mean Harrison Wells.

0celo7

Yes!

user116211

@0celo7: Well; he is back in S2; but from earth 2!! Cisco, in hatred or some of that sort, never calls him Dr.Wells; he addresses him as Harry:/

0celo7

03:18

Cisco is the stupidest name ever

Even worse than Bajoran

ACuriousMind

@0celo7 The Bajorans are a proud race that have suffered terribly at the hand of the Cardassians. They do not deserve your mockery.

0celo7

@ACuriousMind be quiet, Bajoran

go mourn your unfortunate name

@ACuriousMind seriously, no one can pronounce your name :P

user116211

@0celo7: There are countless flash in S2: Barry's Flash; Jay Girrick's Flash from earth 2; Wally West's (yes, detective Joe West has another son, who came from nowhere) Kid Flash; Jesse (Harry's daughter) Quick; the villain: Zoom; and lastly Eobart's Reverse Flash!!!! So, many Flaaaaaasssssshhhhh!!

0celo7

wtf

ACuriousMind

@0celo7 :(

Secret

03:27

This thing is here because U is continuous with time

user116211

They've made it a jumble!!!! I wonder how many flash are more in their pockets:/

DanielSank

Hey guys.

Anyone do anything interesting today?

0celo7

@DanielSank I finally have a job

ACuriousMind

I listened to a talk I did not understand a single word of

DanielSank

^ Academia in a nutshell, eh?

0celo7

03:29

@ACuriousMind it's true, sadly

DanielSank

@0celo7 Nice, like a lab job?

0celo7

it's a nice sounding name if done properly

but no one can do it properly

@DanielSank Si

DanielSank

@0celo7 Well, go on...

0celo7

my first task is to summarize a paper that I don't understand a single word of and is way outside of my comfort zone

and then I have to present it to the group

DanielSank

@0celo7 What's it on? What does the lab do?

ACuriousMind

03:32

@DanielSank All too true

But this one was unusually arcane

DanielSank

That's too bad.

Folks should try to make talks accessible, otherwise they're just wasting everyone else's time.

ACuriousMind

@DanielSank Well, some people in the room understood it. This seminar is just not consistent in the prerequisites, I think the speakers just pick a random point to start in their exposition, and this one started too far in for me

DanielSank

@ACuriousMind Oh I see.

ACuriousMind

It's difficult to set a baseline, though, because the attendance is highly fluctuating based on the week's topic

Secret

for me, Trying to do a time dependent perturbation theory to work out how quick the time evolution operator detect a new interaction (we believed it is ~c as there is no memory of the switch)

Therefore I am currently self learning time dependent perturbation theory using that set of lecture note

DanielSank

03:39

@ACuriousMind Right. That sounds very difficult.

@Secret Memory of the switch?

ACuriousMind

@Secret I, uh, was not actually advising you to go and calculate that. If you haven't learned the rest of basic quantum mechanics, or time-independent PT, do that first.

Secret

I have learned time independent PT from my 3rd year course up to second order (although we lay out the full framework)

my*

0celo7

@DanielSank Solid stat physics under extreme conditions (heat, radiation, pressure)

DanielSank

@0celo7 Neato.

0celo7

@DanielSank Yes, this should give me some experience that the fusion people will find useful when I'm a senior/grad student

ACuriousMind

03:43

@DanielSank Well, it's the organizer's "fault" for doing a completely different topic each week, but it is kind of nice to get a first-hand overview about how many diverse things can be called "mathematical phyiscs" (or "physical mathematics" in this case because there was already a "mathematical physics" seminar :D )

DanielSank

@0celo7 You wanna work on fusion?

0celo7

Sadly there's much less math in it than I'd like

@DanielSank Yes

DanielSank

@0celo7 Here?

0celo7

I don't know yet where...

DanielSank

Cool. Fusion is neat. You wanna build stuff or calculate stuff?

Or both.

0celo7

03:46

Probably calculate. I've never liked building stuff, but I'm not sure hating wooden truss bridges and whatnot counts.

DanielSank

@0celo7 Give building stuff a shot. Then you'll be sure you don't like it if you really don't.

ACuriousMind

@DanielSank: I just realized that I don't know if you primarily calculate or build stuff

...is that even a sensible question for someone working with quantum computers? You probably do both

DanielSank

@ACuriousMind Compared to most of the people around here, I am basically a plumber.

ACuriousMind

That doesn't mean anything, our current dean once said in a talk "Basically, string theory is like plumbing" :D

DanielSank

I calculate some stuff. In fact, I've come across some relatively difficult calculations in my work. I have one right now that I think is rather tricky. I'm considering posting it as a question but it will probably be completely ignored.

0celo7

03:50

@DanielSank fixes borke shit

@DanielSank I hope I get to build something interesting in this job

DanielSank

@0celo7 Well, usually you work up to that, you know?

For example, you have to learn calculus before you can do anything interesting in GR.

To build interesting stuff you're going to have to learn to... build stuff at all.

The best thing you can do is find someone in the lab willing to mentor you and stick by that person. Do whatever they need help with and ask for help as you need it.

Whatever you do, if you're building something take pride in your work.

0celo7

@DanielSank how do you know I didn't do that one backwards

DanielSank

If you do a good job and make things reliable, people will love you.

I can tell you, people who do crappy soldering jobs and waste my time figuring out why something is broken... I do not appreciate that. When I see something done rock-solid I know whoever did that is a true homie.

In a lab you depend on one another for everything.

If you solder a wire well, that wire might run in an experiment for ten years.

@0celo7 I suppose I don't.

0celo7

I can solder pretty well...

Can I get a job at Google now?

DanielSank

@0celo7 Awesome.

One of my interview questions I some times use is to show a copper coax cable and ask the candidate what they think of it.

It has an SMA connector soldered on each end. One end is crap and the other is good.

ACuriousMind

03:59

You have an interview cable you use to test people?

That's an...interesting approach

DanielSank

We're a hardware lab, dude.

0celo7

real science

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