The h Bar

AccidentalFourierTransform

20:00

@ACuriousMind I have one, but this comment is too narrow to contain it

DanielSank

@AccidentalFourierTransform Hi.

Semiclassical

Someone needs to do a William Goldman-style adaptation of ncatlab

ACuriousMind

Hopefully that right there wasn't AFT's last theorem :P

Semiclassical

which is to say, only the good parts :P

Bernardo Meurer

@ACuriousMind Lol

@DanielSank Hire me

AccidentalFourierTransform

20:01

@DanielSank look who finally showed up :-P

how are you

DanielSank

@AccidentalFourierTransform Good. How are you?

AccidentalFourierTransform

im all right

It's nice in here, I like the weather

DanielSank

good

AccidentalFourierTransform

although North America is weird

I can't buy wine at the supermarket

Bernardo Meurer

@AccidentalFourierTransform IKR

AccidentalFourierTransform

20:03

what's up with that?

Bernardo Meurer

It's ridiculous

NA is so flipping conservative

DanielSank

@AccidentalFourierTransform Sure you can.

Bernardo Meurer

Honestly Mexico is the only sane country in north america

AccidentalFourierTransform

Im not going to go to a liquor store, that's for drunk people

Semiclassical

It varies from state to state.

In MN, you can buy liquor at a grocery store but that part of the store is technically separate from the rest

AccidentalFourierTransform

20:04

@DanielSank where? in the aisle next to the guns? ;-)

mexico is south america (cc @EmilioPisanty)

Semiclassical

"Off sales of liquor are restricted to licensed liquor stores. Liquor is only sold in liquor stores, not supermarkets as you may be used to from other states, or gas stations as Wisconsin does. Some supermarkets operate their own liquor store right next door to their food supermarket, notably Trader Joe's...3.2 beer is less strictly regulated. It can be sold in grocery stores and it can be sold on Sundays. High alcohol spirits like Everclear are illegal in Minnesota."

DanielSank

@AccidentalFourierTransform do you want to talk about physics or discuss United States social and legal situation?

Semiclassical

by contrast, Wisconsin's laws are a good deal weaker. So that means you occasionally have people driving over the border to buy alcohol and drive back

DanielSank

I'm at work. I just had lunch so I can talk a bit, but I have things to do.

dmckee

@AccidentalFourierTransform Depends on the state. And in some states on the county (key phrase "county option").

AccidentalFourierTransform

20:07

@DanielSank physics is fine I guess

although discussing the idiosyncrasy of NA is much more fun tbh

Bernardo Meurer

the US is insane when it comes to alcohol

DanielSank

@AccidentalFourierTransform I'm happy to stick to that, if you want.

Semiclassical

parts of the US

dmckee

The funny thing is that in dry counties you can spot the county lines because every road into a neighboring wet county has a liquor store right on the other side of the line.

Bernardo Meurer

@dmckee Lol

Semiclassical

20:08

the US is too big and weird for it to be consistent

Bernardo Meurer

@Semiclassical Brazil is large and it's consistently alcoholic

I don't buy that argument

DanielSank

@Semiclassical Thank you for saying that.

dmckee

They say of prohibition that the nation voted dry and drank wet. This is just an extension of the same.

Semiclassical

hmm

Bernardo Meurer

We all bond over our hate for our livers

Semiclassical

20:10

The thing which complicates the US/Brazil comparison is that, while they're roughly comparable in square miles, I'm not sure how the population density compares

DanielSank

Yeah that and the very different economic situations.

Bernardo Meurer

@Semiclassical Actually, I think that's very similar. Some large, very dense, metropolitan areas, and then large spots of land with no one in them but cows

Semiclassical

actually, even that's probably too simplistic considering how drastically the population density varies

Yeah.

Bernardo Meurer

The U.S. has more people tho, about 90 mill more

Semiclassical

I'm still not convinced it's an apples-to-apples comparison.

DanielSank

20:11

Bernardo, movie tomorrow?

Bernardo Meurer

@Semiclassical Well, nothing ever is

@DanielSank I'm moving?

Ah

Semiclassical

I would also tend to think that you tend to have more dry counties in rural areas of the US than in urban areas

Bernardo Meurer

Yes, let's!

Black Panther, State St, Dinner?

DanielSank

@BernardoMeurer yeah that works.

Semiclassical

which I guess means the point shifts from "the US is weird on liquor laws" to a more specifically rural context

DanielSank

20:13

^

Bernardo Meurer

@DanielSank Deal, let me check times

@DanielSank What cinema is the good one in State?

@Semiclassical The 21 drinking age is my pet peeve

DanielSank

It's absolutely incredible how often a European says "The United States is messed up in {some description of a thing that is messed up in some part of the United States, but which is also messed up in some parts of Europe, just not their home country which is the size of a medium US state}".

Bernardo Meurer

Because far more dangerous things than drinking are 18

dmckee

@BernardoMeurer Not fair. I'm getting nostalgic.

Semiclassical

You can blame drunk driving for that, I think.

DanielSank

20:14

@BernardoMeurer There are only two.

Bernardo Meurer

@dmckee Awww, come join!

Slereah

btw the good version of Haag's theorem is in Streater and Wightman

it is stated fairly straightforwardly

Bernardo Meurer

@DanielSank Metro 4 and?

DanielSank

@BernardoMeurer The Arlington, which only has one screen.

Bernardo Meurer

Ah, right

DanielSank

20:15

Oh no, wait... there's another one.

Bernardo Meurer

Ye

DanielSank

Whatever. Just pick something.

Bernardo Meurer

I thought it was 3

k

Semiclassical

Though I tend to think we're pretty silly with drinking laws anyways. Young people in high school do drink; I'm not sure restricting it like we do really helps with that.

dmckee

@BernardoMeurer Can't Astro lab tonight.

@DanielSank One screen but it's a classic.

Semiclassical

20:16

(And the puritanical obsession with marijuana is just absurd. no argument there)

DanielSank

@Semiclassical Yeah except that that's quickly dying.

AccidentalFourierTransform

well what about the nutrition info on food?

DanielSank

@AccidentalFourierTransform Other countries do that too, don't they?

AccidentalFourierTransform

no consistency there

Semiclassical

I'll agree that it's fading.

I'm not sure I'll agree with 'quick.'

DanielSank

20:17

I've seen food with energies quoted in Joules.

@Semiclassical It's already dead in several states, including California.

AccidentalFourierTransform

@DanielSank not in the UE - here it's x grams of sugar/100 grams of product

always

Bernardo Meurer

@DanielSank metrotheatres.com/movie/198436/Black-Panther/2018-04-05

ACuriousMind

@AccidentalFourierTransform UE?

AccidentalFourierTransform

EU

ACuriousMind

The Ü.

Semiclassical

20:17

Sure, but at the federal level it's firmly entrenched.

Bernardo Meurer

@DanielSank In Brazil it's mandatory to say how many joules your food have ( no joke)

DanielSank

@BernardoMeurer Right. Here it's Calories.

Semiclassical

I think marijuana will ultimately get legalized, but I don't foresee it going quickly.

DanielSank

Ok, 18:20 show tomorrow.

@Semiclassical It's already happened, dude.

Bernardo Meurer

@DanielSank Yeah, they make you put both IIRC

@DanielSank Deal, 18:20

DanielSank

20:19

Legality of cannabis by U.S. jurisdiction

In the United States, the use and possession of cannabis is illegal under federal law for any purpose, by way of the Controlled Substances Act of 1970. Under the CSA, cannabis is classified as a Schedule I substance, determined to have a high potential for abuse and no accepted medical use, thereby prohibiting even medical use of the drug. At the state level, however, policies regarding the medical and recreational use of cannabis vary greatly, and in many states conflict with federal law. The medical use of cannabis is legal (with a doctor's recommendation) in 29 states, the District of Columbia...

Semiclassical

"At the state level, however, policies regarding the medical and recreational use of cannabis vary greatly, and in many states conflict with federal law."

DanielSank

Yes.

But in 8 states it's already completely legal.

AccidentalFourierTransform

I couldnt care less about marijuana but I want my mother-fn wine

DanielSank

This is going to go the way of gay marriage. More states will switch and then the federal government will change policy.

AccidentalFourierTransform

is it legal in Canada?

ACuriousMind

20:21

I find it pretty funny how some of you said "let's talk physics" and then directly proceeded to discuss everything but that from drug policies to nutrition information :D

DanielSank

@AccidentalFourierTransform So go buy some. Where in the USA can you not buy wine?

AccidentalFourierTransform

in Ontario, USA

Slereah

@ACuriousMind Streater has a chapter on QM and drug policies in his book

DanielSank

@ACuriousMind I came here to talk physics with AFT, but he chose to talk about this stuff instead. I'll leave soon, and poor AFT won't get answers to his question.

Semiclassical

I think that's a spurious comparison. I don't think there's going to be a Supreme court case which rules marijuana regulation as unconstitutional.

ACuriousMind

20:22

@Slereah huh

Semiclassical

I mean, do you think gay marriage would be legal at this point if it was left up to Congress to decide?

Slereah

@ACuriousMind To expound the importance of conditional probabilities

DanielSank

@Semiclassical It's hard to say, but I don't get your point.

When the states and the fed disagree, it goes to the court. That's how the system is designed.

Semiclassical

Only when it's not clear which of them has priority.

Bernardo Meurer

Honestly I turn 20 this month

And then it's just one more year until I can legally drink again

And I swear to god

DanielSank

20:23

@Semiclassical Right, which could happen if someone e.g. transports a lot of pot across state boarders.

Bernardo Meurer

I am going to die when I can drink again

April 30th 2019 is the day I die

AccidentalFourierTransform

why dont you make moonshine at home?

Bernardo Meurer

@AccidentalFourierTransform Because my housemate is a prude

DanielSank

Buddy Holly & The Crickets - That'll be the Day

►

ACuriousMind

@AccidentalFourierTransform Why don't you make your own wine? :P

Or ask @DanielSank for mead recipes

Bernardo Meurer

20:24

@DanielSank Exactly :P

Slereah

@ACuriousMind Because home made wine is terrible

Bernardo Meurer

@DanielSank Make me mead

DanielSank

@BernardoMeurer WTF?! I thought your housemates were Scandanavian.

AccidentalFourierTransform

NA wine is terrible anyway

Slereah

Home made wine is reserved for people stranded on a desert island or prison

Bernardo Meurer

20:25

@DanielSank Yes, but they're swedish, they hate alcohol and fun

DanielSank

@ACuriousMind I didn't forget that I promised you mead. I just haven't made more, and the last batch wasn't good enough to share.

Semiclassical

The other point I'd make is that getting sensible Supreme Court decisions relies on having sensible Supreme Court justices.

DanielSank

@BernardoMeurer I'm pretty sure Swedes don't hate alcohol.

Bernardo Meurer

You can go around showing your titties, but you can't have a damn beer WELCOME TO SWEDEN

@DanielSank Any country that forbids open containers in public hates fun and alcohol

ACuriousMind

@DanielSank it's fine, you tried to send me some once but it turned out you would have needed something like an alcohol export licence or whatnot, remember?

Semiclassical

20:26

My overall point being that, while I think marijuana legalization will come in time

Bernardo Meurer

Also, from here onward when I say "fun" just know I mean "alcohol"

DanielSank

@ACuriousMind Yes, well...

AccidentalFourierTransform

sunday funday

Semiclassical

that doesn't mean that I expect the federal govt to flip on it any time soon

especially to the extent that it's a policy being enforced by the current administration

I mean, look to the liquor laws. Prohibition was repealed how many decades ago, and we still have weird liquor laws

dmckee

@BernardoMeurer Hmmm ... the way I recall it from my undergraduate days, it was very easy for ... uhm ... a friend to get booze despite being underage.

Semiclassical

20:28

Do we really expect that marijuana is going to change faster than that?

AccidentalFourierTransform

ah, the good old days of fake id's

dmckee

IN fact you could get cases Keystone Lite in IV for less than cases of soda.

Bernardo Meurer

@dmckee Not on the quantities I require for survival

DanielSank

@dmckee Sir, beware what you are saying!

Bernardo Meurer

Back in Rio I had a deal with the supplier

dmckee

20:29

Which in a sensible world would be because no one wanted Keystone lite. But this was U Can Study Buzzed in the nineties.

ACuriousMind

@DanielSank Sweden actually has a pretty strict regulation on alcohol sales and a state monopoly on selling bottled alcohol (as opposed to drinks in bars)

Bernardo Meurer

^

DanielSank

No respectable student like Bernardo Meurer would ever think to subvert the law of his host nation simply to imbibe a small quantity of ethanol...

Bernardo Meurer

@DanielSank All I do is subvert the law

I've done a lot more for a lot less

Semiclassical

subverting the law, subverting the law

hmm, not quite as catchy

dmckee

20:30

I subverted the law and the law won. Doesn't scan.

AccidentalFourierTransform

lol

Bernardo Meurer

lol

skullpatrol

:D

DanielSank

I have no idea what's going on here any more.

Bernardo Meurer

@DanielSank David is trying to get me to become a criminal, but he doesn't know it's too late

skullpatrol

20:35

Smooth criminal

Slereah

$C^r$ criminal

ACuriousMind

Piecewise continuous criminal?

Bernardo Meurer

Lol

Semiclassical

analytic criminal

AccidentalFourierTransform

5

ah, what a beautiful country

Smooth operator

Bernardo Meurer

20:38

@AccidentalFourierTransform Lol, oh my god

ACuriousMind

@AccidentalFourierTransform I, for one, welcome our new geese overlords.

AccidentalFourierTransform

STARE DOWN THE FUCKING GANDER

dmckee

Anyway, I posted this further up incorrect addressed to @Emilio, so let's try again:

@AccidentalFourierTransform*"What prevents me from saying that the electromagnetic field is a probability amplitude?"* Can you get the distinct rules for coherent and incoherent outcomes with classical electromagnetic fields?

And do we dare ask Marty if he has any papers to recommend?

AccidentalFourierTransform

hmm I don't know

what is coherent/incoherent?

I dont know much about physics btw

dmckee

@AccidentalFourierTransform Fermilab's biggest source of reportable injuries are the large number of Canada geese that nest there every year.

Bernardo Meurer

20:41

@AccidentalFourierTransform You're at fermilab?

dmckee

@AccidentalFourierTransform If there are multiple ways to achieve a particular result to your experiment the probability that you get that result can be computed in two distinct ways:

AccidentalFourierTransform

oh, we have something similar in my hometown, but with storks

dmckee

(A) You can add the probability amplitudes and the square the sum to get the probability.

AccidentalFourierTransform

you cannot take down their nest, it's illegal

but they are very heavy and big

dmckee

(B) You can compute multiple probabilities by squaring the individual amplitudes and then add to get the overall probability.

AccidentalFourierTransform

20:42

and they will block chimneys and whatnot

Bernardo Meurer

@AccidentalFourierTransform Reminds me of that time when Fermilab employees had a war with invading raccoons

dmckee

Which you do depends on whetehr or not you can tell which "route" gave you the result.

AccidentalFourierTransform

@BernardoMeurer no, Im in Canada

where is fermilab by the way?

Bernardo Meurer

Illinois

dmckee

@BernardoMeurer I've worked at Fermi a couple of times. Once for a summer and once for a year. Come spring a lot of information about the geese gets posted.

Semiclassical

20:44

Not too far from Chicago iirc

Bernardo Meurer

> "At 1:24 a.m., Operations reported a raccoon attack in the Linac gallery. It seemed to be a coordinated effort. Fortunately, by 1:53 AM, a joint force of operators and Pbar experts managed to drive the raccoons out of their hastily made fortifications.

AccidentalFourierTransform

@dmckee well, you do certainly add electromagnetic fields, and then square the result to get the intensity (which is what you measure)

Bernardo Meurer

@dmckee Lol

dmckee

@AccidentalFourierTransform Right, but do you also get the case where you square the fields separately and then add the results?

AccidentalFourierTransform

I'm not sure -- optics never was my cup of tea

ACuriousMind

20:45

...or glass of wine, as it were

dmckee

Hmmm ... on thinking about it you can square the RMS field intensities and then add the results for (wait for it) separate, incoherent beams impinging on the same detector.

But those are averages, and I'm not sure it is the same thing.

AccidentalFourierTransform

oh and how come the only brands of coffee you can get at the supermarket are McDonalds, Starbucks, Tim Hortons, etc.?

I want some real coffee

not some fast food chain bullshit

Semiclassical

blame consumer culture for that

ACuriousMind

@dmckee I don't understand the question. Let's take the electrostatic field of a single charge. For what event is that even supposed to be a probability amplitude?

Bernardo Meurer

@AccidentalFourierTransform Buy online?

dmckee

20:49

If you can find an unaffiliated local coffee shop they probably sell unbranded, high-quality coffee by the pound.

Semiclassical

It helps if you're in a college/university town

AccidentalFourierTransform

@BernardoMeurer shipping costs are rather high here

dmckee

@ACuriousMind This discussion is spill over from

6

Q: What makes a theory "Quantum"?

Say you cook up a model about a physical system. Such a model consists of, say, a system of differential equations. What criterion decides whether the model is classical or quantum-mechanical? None of the following criteria are valid: Partial differential equations: Both the Maxwell equations ...

Bernardo Meurer

Here in SB I get my coffee eiither from French Press or Handlebar

dmckee

I proposed that probability amplitudes in some form are a necessary feature of quantum theories that are not part of classical theories.

Not that I'm positive about that, but it was the first thing that came to mind.

Semiclassical

20:52

"Can you violate Bell's inequality?" might be another criteria

dmckee

AFT asked how that differed from electric fields (presumably talking about $I \proprto E^2$ for light, or so I took it).

ACuriousMind

@Semiclassical You can build strange theories that are completely different from quantum mechanics that also violate Bell, though

AccidentalFourierTransform

Im not sure the concept of probability is crucial here -- some would argue that the emergence of probabilities is only due to our measuring methods and things like decoherence

Semiclassical

fair.

Bernardo Meurer

I violate Bell's Inequality all the time

AccidentalFourierTransform

20:54

why would you

please be nice

ACuriousMind

@AccidentalFourierTransform Well, I'm not sure the concept of "quantum" is really a well-defined property of a theory rather than being extensionally defined by "we call this collection of theories quantum and this collection of theories classical".

AccidentalFourierTransform

yeah, that's kind of what I thought

I really cant define what it means to be quantum

ACuriousMind

GR is "not quantum" because it has no unification with the rest of the theories that are "quantum".

DanielSank

@BernardoMeurer eh?

AccidentalFourierTransform

when we say "we need to quantise gravity", what do we exactly mean by that?

DanielSank

20:55

Oh sure, now we're talking about physics, after I left.

Jerks.

Semiclassical

lol

ACuriousMind

@AccidentalFourierTransform I really think it means "we want a theory which has both QFT and GR as limits".

Bernardo Meurer

So, US laws

Now that Daniel is back

What's the deal

AccidentalFourierTransform

well, just because we cant couple two theories doesn't mean they are not both quantum mechanical, right

so it's not a problem about quantisation

we may agree they are both quantum mechanical, and we dont know how to get them to work together

ACuriousMind

@AccidentalFourierTransform Well, a priori GR looks a lot like any other classical field theory, so we put it in the bucket that says "classical" on it.

AccidentalFourierTransform

20:57

GR looks a lot like the Schrödinger equation too

ACuriousMind

As I said, I don't think "Is this theory quantum?" is a question about anything but language conventions

Semiclassical

I think you could put a quantum information spin on this as follows.

DanielSank

I agree with @ACuriousMind.

AccidentalFourierTransform

I have to pee

Bernardo Meurer

'Look to my coming on the fifth day. At dawn, look to the east.' 'And look to the west to see our shadows!'

DanielSank

20:58

@AccidentalFourierTransform Schrodinger's equation is literally the diffusion equation with $t \to i t$.

@BernardoMeurer lolololol

Bernardo Meurer

@DanielSank ikr?

I laughed hard at that one

Semiclassical

Suppose you have two observers, each with access to some set of observables. For simplicity, I'll take those observables to all be dichotomic i.e. results are either +1 or -1.

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