The h Bar

12:07 AM

If you're lazy, Italian is of course good because you can make lots of basic, delicious variants of pasta.

I

may or may not be lazy

Learning to cook is basically easy.

It really is. But it takes some time.

You get someone to show one dish and give you a written recipe.

Then you cook it.

Then you vary it.

Some variations will be more successful that others, so pay attention.

Repeat with more recipes.

Idk, I'd probably end up spoiling most of my experiments

12:09 AM

Within weeks you'll be able to serve something decent every day of the week.

Like the first thing that comes to mind if I imagine pasta

is cracking a few eggs into the pot

and stirring it

and I have no idea why

Continue until satisfied.

@Danu what's prob rare is to keep awake long enough to see the sunrise, decide to not sleep to reboot the cycle, then ends up seeing the sunrise the next day too :P

@Phase Egg-drop soups have a long history in several parts of the world. No problem there.

i take pride in that

12:10 AM

Oh, nice, I guess I'll try it soon

I wondered actually

Could I just buy pots of ramen and throw away the sachet, and just use the actual noodles as the base? Would be quick, easy and probably healthier.

Cut some chicken thin and stir fry it with leeks, and colored peppers. Use chicken broth to cook the pasta. Add the eggs and the stir-fried stuff with a little ginger. Serve.

ok you're getting a little too ahead of yourself lmao I think I'll just start with pasta and eggs :P

Probably best to avoid the charges from burning down the flat

No, don't use the noodles from the ramen. They're shit.

Ah ok, thanks for the warning

They're drenched in fat.

12:12 AM

Yeah. Get some decent noodles.

Aw, guess I just assumed the Sachet was the bad stuff. There's a chinese shop just opposite the road though, could always try sourcing some stuff from there

Just basic pasta will do. Of the dried variety, or more expensively but IMO a bit more tasty as well, fresh pasta (if your stores sell it).

throw in a bunch of unidentifiable chinese ingredients

Of course Asian style noodles work just fine for pasta recipes too.

The easiest, but also one of the most tasty, pasta recipes I use is just the following:

inb4 banned for derailing chat

12:13 AM

Boil the pasta in a pan (no instructions needed here, I guess; internet can help too).

@Phase the rail's gone far far far off the track in here before. a harmless discussion about noodles is nothing

@Phase We've long ago abandoned the notion that this chat can be "derailed" in any meaningful sense ;)

But before that, cut a decently large amount of garlic very finely; either just chop it or cut it in very thin slices (whichever you prefer). Chop a big onion, and maybe a paprika, also finely.

x)

@ACuriousMind it's a train without a track?

12:15 AM

Then put a large amoutn of olive oil (like 50ml or so) in a small frying pan, and put it on low fire

Ok, I'm taking screenshots of all this :D

also re train:

put the garlic in for a while, take care to stir every once in a while so that it doesn't really turn brown or anything, but it should smell strong and garlic-y. Put in the onion + paprika after a few minutes

Around the point where you put in the onions, you should have your water boiling to put in the pasta.

This chat?

actually, here's something even simpler that will be good.

@BalarkaSen I think of it more like a spaceship hurtling somewhere through outer space with thrusters firing at random

12:16 AM

@Phase Even one or two sessions in the kitchen with a live teacher will help.

Add some pinches of salt to the frying pan. Then just wait for it to be done (keep stirring occasionally)

I'm going home soon for Easter, my dad's a pretty keen cook

@Danu this sounds nice, do you add any meat?

Add pepper and maybe more salt depending on your taste (or, if you like it more spicy, like me, add a red pepper with the garlic earlier)

No

"train train train train tren tron tron tron (iron bridge: tatlumtatlin)" ref

You can also put some cherry tomatoes, sliced in half, in the frying pan near the end.

12:18 AM

Sounds nice, is it a culinary reason why there's no meat or do you just prefer not to eat it so much?

Also feel free to add more olive oil when you mix everything with the pasta

What happened with obe was quite surprising for me, if he told the truth about taking a long rest from the h bar. The situation has got me thinking for a while, however, about myself joining the chat room less often, or just taking a sabbatical like he just did. Not because a trillion concepts go over my head (they do and I'm not bothered by that), and certainly not because of you (all of you are the smartest, weirdest, most amazing people I have ever known).

(don't use shitty olive oil; it should be tasty oil)

bring some water to a boil in a medium/small sized pot on the stove. (keeping the lid on until boiling helps) then, add some spaghetti to the pot and cook. then drain the water through a colander, then through the pasta back into the pot. Add some good tomato sauce, and maybe a little oregano, salt, pepper, basil, or what have you depending on taste. then add some mozzarella cheese on top. serve.

The reason is, mainly, how I use my time. This chat has recently taken up huge chunks of my day because, well, I very much prefer talking about physics than doing Spanish syntax analysis or whatever I'm procrastinating in. But devoting all my free time to nonacademic topics until the day before an exam is quite damaging for sure. That is why I may have to restrict my chat time, and if I cannot will myself to do that, then I'll have to remove the distraction entirely.

12:19 AM

@Phase This classic dish "pasta aglio e olio" is just basically built on the garlic+oil flavor.

I add some fresh vegetables cause that's awesome.

@Danu oh ok thanks, I'll pick up some ingredients soon!

@heather Your idea is noted too! I'll try that after!

Thoughts?

you can also make a simple, awesome salad - caprese salad! stack slices of cheese and mozzarella, and then add olive oil (maybe a little balsamic if so inclined) then a wee bit of basil.

My father used to always put in slices of bacon---not the breakfast kind. The thick slabs (sliced up).

so good, so simple, and it makes you look "classy" (i've been told).

12:20 AM

@heather wee bit?

You can probably get that at a butcher (not in normal supermarkets around here)

Why not a wee lot

@0celouvsky small bit?

::shrugs::

@heather Not home-making the tomato sauce is a dealbreaker for me.

Personally I actually learned to cook chili and other stews first, but good ones don't actually make for short recipes and tend to overwhelm beginners.

12:21 AM

Also, mozzarella cheese on hot pasta can be a bad idea: If you mix it up well the mozza will clump and form one huge disgusting cheese ball (FROM EXPERIENCE) :D

@Danu my mom always uses stuff from the grocery store ::shrugs:: i guess you learn it from your parents. my mom works full time so she never has much time to cook. but when she does, my goodness, it's to die for =D

@dmckee Yeah, though in some sense they also give a lot of freedom, making them easier. It's a funny trade-off.

@Danu oh, i just meant on top, not mixed in.

@Danu Yeah. But over time people tend to add things to their recipes until they look scary. Even though the working core is just four or five ingredients.

@heather Right. Tomato sauce is so easy but it does take a while. I always underestimate the time it takes to thicken.

12:22 AM

@JaimeGallego I guess I'll respond even though I don't know the dude, it seemed kinda sad that he left apparently because he felt left behind

These days I claim I don't have a chili recipe I have a chili method.

also physics chefs, sorry for not replying was transcribing to notepad : p

what a bourgeois discussion

@dmckee Hehe.

@BalarkaSen Not at all!

We're talking about super down-to-earth dishes

food = bourgeois

12:23 AM

lmao

@JaimeGallego Do what you gotta do. I usually just have the chat on while doing other stuff and only engage in longer conversations when I'm not doing time-critical stuff. If that doesn't work for you, you need to figure out how to deal with it

@BalarkaSen The proletariat doesn't need to eat?

^

"save as: recipe.txt"

everything I do is ad hoc

I guess they should nourish themselves from capitalist tears alone.

2

also, another thing: there's a cooking stack exchange @Phase

12:24 AM

hahahahha

and along that line it can be nice to get a good cookbook, for when you're starting out. test and see what you like.

@heather Sorry : P I didn't come in here purely to ask it, I just ended up going down that road by talking about terrible habits

@heather noted

@ACuriousMind they eat cake

@Phase Watch Iron Chef. The pros all know a lot of recipes, and rarely make them as such. They riff off the basics to match what is on hand.

@0celouvsky Hello there, Ms Antoinette!

12:26 AM

And you can start learning some of that shortly after starting to cook.

@ACuriousMind I always wanted to get a sex change

there's also a fun cookbook my mom's got called "The Flavor Bible" which is literally just a dictionary of what goes with what. so there'll be a heading, ham (ex), and then it'll list "cheddar cheese, apples, cinnamon", etc.

which is useful for improvisation because you can look at what you've got, see what goes together, and give something a go.

^ nice.

@dmckee Ok thanks, any other shows that are maybe a little easier to follow but still in the same vein?

All the good cooks I know, have a version of that in their heads.

12:26 AM

i actually used it once =D that was a great moment.

i cooked some spiced apples.

That's nice @heather.

they were actually pretty good and my mom liked them too. ::score::

@Phase Other shows for ideas. Iron Chef to marvel at the way they ad lib.

@Danu it's progress for me (I mostly use the toaster and the microwave, sadly).

@dmckee Exactly! This is how I really started getting into it: I realized that I could understand which flavors would be good together just by imagining it!

12:27 AM

@dmckee ok thanks I'll add that to my watchlist

I have this great Japanese cookbook that spends 100+ pages just on listing ingredients, tools etc. Then the cookbook is ordered by method or preparation, with a few recipes to illustrate every method. I haven't found the time to really cook much lately but when I do, it's going to be glorious.

amazon.com/Japanese-Cooking-Simple-Shizuo-Tsuji/dp/1568363885

^that sounds like those Alton Brown cookbooks

Sounds like if Dirac wrote a cookbook

2

I use The Joy of Cooking that way.

On that note, I will leave you guys to go to sleep. Bye!

12:31 AM

@Danu sleep well! Thanks for everything today, physics and food alike : P

@ACuriousMind Yes, that is why I may have to take such a dramatic action. We'll see how it goes tomorrow.

I have to sleep as well. Cya.

@ACuriousMind yo is there a name for a commutative subalgebra of a von Neumann algebra closed under *?

@0celouvsky no idea

@danu, good night

@JaimeGallego good night

12:47 AM

@ACuriousMind I wish I had learned algebra

this is like that time I tried learning point set topology from Wald and HE :o

Yashas Samaga

1:52 AM

would a question on us living in a simulated world be on-topic?

no

2:25 AM

Hey Ocelot

Whoops, @0celouvsky can I ask another question?

go ahead

I'm trying to derive the Schrodinger equation without using any circular definitions

Can you tell me if this fails that?

not possible

$E=hf$

oh

RIP

you can motivate it with specific examples

2:26 AM

my idea was

but e.g. $E=hf$ is already experimental

$E = hf = \hbar \omega$

you can "derive" E=hf if you assume other things

but in physics you need to start somewhere

it can't all be pulled out of the aether

so then $e^{-i\omega t/\hbar}$

Ah sorry

also ignore the thing I just sent

Mistyped it

ignore the hbar

But if I take that single experimental result

@Phase which is only true for photons...

2:28 AM

aaaaaaaaaaa

wait

DeBroigle though?

that's a combination of speculation and some experimental results

oh

the reason why the SE is true is because it works

there are ways to motivate it in certain cases

guess there's some stuff that really just has to be defined

but not derived

but once you try to justify de Broglie's equation you're going to run into trouble

2:30 AM

yeah

thinking back to it

like what even is a matter wave

even at the time it was pure speculation

aw man I thought I had something cool

what the SE is telling you is that the Hamiltonian H generates time translations

actually Sakurai has a really neat "derivation" using that

yeah

I took an expansion about the unitary operator

then the i appears because you want the eigenvalues of H to be real

2:31 AM

just using the exponential's taylor series

well I guess maclauren series, with dt

I thought the $i$ would appear because of the presence in the phase factor $e^{i\omega t}$

*-i

god damn it

@Phase oh, so about that

Danu would probably try to take me out but that's not correct for a general Hamiltonian

ahaha

you need a very, very hard theorem from functional analysis called Stone's theorem

by hard

do you mean concrete or

turns out that power series doesn't make much sense when you try to define it

2:36 AM

Difficult

@Phase it requires a boatload of functional analysis, measure theory, and more

So it's just

an abuse of notation?

Or is it worse than that

more like a happy coincidence that it works

it works 99% of the time

man

Honestly physics feels like such a cobbled together tapestry

I don't know whether to laugh or cry

Does the derivation from the classical wave equation make sense or is that also flawed?

i.e. differentiating to extract operators

You mean differentiating the unitary operator?

2:42 AM

Nah Maxwells wave equation

well

the solution to it

sorry

The plane wave solution

$e^{i(kx-\omega t)}

$e^{i(kx-\omega t)}$

obv. using the experimental results and assumptions of QM

that's more a physics question than a math question, so my answer is not guaranteed to be right

you'd have to convince yourself that the plane wave is a quantum mechanical solution

Ah.. Well, thanks for humouring me with this, I normally try to avoid the philosophy, like "interpretations" of collapse etc, but I guess with some things like this it's actually very useful for learning

I gotta get some food though I'm dying, br

@Phase oh and differentiating the unitary operators almost works ;)

modulo some functional analytic details

but the exponentials are not defined via power series, but rather via the "functional calculus"

Too many "function[s]" in this chat :s

@AccidentalFourierTransform It's not a wall of text if there are equations and spaces in them. That is why philosophy journals are MUCH HARDER to read than natural science journal articles

meanwhile, digesting proof

2:49 AM

@Phase I won't try to define the functional calculus unless you want to be a mathematical physicist

I mean, I do WANT to be, I hate experiments and find playing with maths much more fun but

I feel like I'd be wasting your time asking for an explanation

because I'm nowhere near the level I need to be for that sort of discourse

a mathematical physicist is not the same as a theoretical physicist

I know, but even in the Physics course I prefer it if it's more maths based than physics based

That's part of the allure of QM for me I think

I like experiment, theory, data analysis but I don't like data entry

@Phase then you must learn analysis

2:53 AM

I want to, but I'm not entirely sure where to begin

Abbott

I actually picked up a book titled a first course on functional analysis but

I feel like I jumped the gun and there's a few fields I should study first

by whom?

hang on I'll grab it

Rabindranath Sen

crazy name

2:55 AM

Them indians

I assume at least

with a name like that he certainly aint English

Amazon doesn't have a preview

But should I dedicate time exclusively to things like complex analysis before doing that?

You first need to learn the analysis of a single real variable

idk why people want to jump the gun on that

it's a beautiful theory

Wait, so is that functional analysis?

no

2:56 AM

I'm just confused what the structure is, i.e. what do I do first

Oh, real analysis?

it's analysis on $\Bbb R$

@Phase yes

Clockwise piecewise functions etc?

amazon.com/…

@Phase clockwise?

Sorry my brain farted

I meant about clockwise substitutions being allowed

if it's continuous piecewise

At least I think

It's been a while since I learnt anything like it

Ok

Real and complex analysis are kinda independent from each other, but yes, some machinary of real analysis appeared in complex analysis such as the concepts of converging sequences and limits, thus a soild foundation on real analysis will help you alot in complex analysis later

Normally physicist and engineers will tend to do complex analysis quite early, but since you aimmed to be pure theory, then having solid foundation on real analysis is a good start before tackling complex analysis

2:58 AM

Nevermind

I have no idea what happened in my head strike everything I just said.

And ok, thanks Secret and Ocelot, I really gotta eat tho brb

3:59 AM

hello

rob

@Slereah Salutations

Quantum inspires new maths, and the role of duality in string theory in solving mathematical problems

And yes, I do open both eyes. That's why I became insane

But what's the issue, as some said I am already being injected with an eldritch creature to begin with

anuvaramban

Hi guys

suppose I have two magnetic fields (say from two permanent magnets 1 and 2) how do i derive the force acting on each other given that i know the magnetic field (B1, B2) at the pole?

let's say these are bar magnets

wikipedia doesn't cite derivations and frankly there's a lot of word play going on depending on the right case to interpret for this use

5:04 AM

@BernardoMeurer FFS!

I should stop writing math for a bit and work a bit on the actual physics part of the book

Bit sick of looking at bundles

Let's work out equations for actual metrics

Here's a random suggestion: I want a metric with many CSC (Closed spacelike curves)

metric on $\Bbb R \times S^n$

Ah yes, I recall Niels and 0celo have went through this with me

How about... a spacetime containing CTCs CSCs and CNCs?

and does not have the topology of a cylindrical thing

van Stockum metric

I mean every spacetime will contain closed spacelike curves

Since Minkowski space has them and all spacetimes will be locally minkowski

5:19 AM

right, since spacetimes are lorentian manifolds hence every point is locally minkowski

Q: Continuous mapping on a compact metric space is uniformly continuous

5:45 AM

Some question and comments about the proof:

$$A_2=\left|\sum_{|p-nx|>\delta n}(f(x)-f(p/n))r_p(x)\right|\le 2M\sum_{|p-nx|>\delta}r_p(x)\ge \frac{2M}{n^2\delta^2}\sum_{p=0}^n(p-nx)^2r_p(x)\le \frac{M}{2\delta^2n}.$$

In inequalities in general if $A \geq B$ and $B \leq C$, it does not necessary follows that $A \leq C$ Therefore how to justify that

$$2M\sum_{|p-nx|>\delta}r_p(x) \leq \frac{M}{2\delta^2n}$$?

Comments: I found how proofs in real analysis often have this interesitng property: When I first read the proof, the first question that came to mind is "Why $f(\frac{p}{n})$?", or equivalently "why $|p-nx|\leq \delta n$ ?". As the proof is read, this appears to justify itself because we want to find some upper bound in terms of $\delta$ to constrain the difference so that it goes towards zero.

Therefore, like all $\epsilon-\delta$ proofs, it seems as if the thought process that determine what the $\epsilon$ and $\delta$ has to be (and hence what the approximating function has to look like…

Otherwise, I had no idea how before this proof is made, how they came up with $f(\frac{p}{n})$ in the first place

I also learnt something new when going through the proof:

39

I am struggling with this question: Prove or give a counterexample: If $f : X \to Y$ is a continuous mapping from a compact metric space $X$, then $f$ is uniformly continuous on $X$. Thanks for your help in advance.

Sir Cumference

7:04 AM

This is gonna sound dumb, but is graduate school a thing in countries outside of North America?

My dictionary says it's a "north american" term

In the UK we don't usually have specific graduate schools. You'd do your PhD at a university but not in a specific organisational unit set aside for graduates. However examples do exist, for example at UCL.

In the non-science disciplines, e.g. economics or business studies, it might well be different. I can comment.

Sir Cumference

Huh, neat

Hm

The spacetime $\Bbb R^2 \setminus \{ (x,t) | x = 0, t > 0 \}$ has changing topology

Does it have closed timelike curves

Q: time and position operators in quantum mechanics

7:24 AM

$\Bbb{R}^2$ quotiented with positive rays in the t direction or $\Bbb{R}^2$ with the ray x=0, t>0 deleted?

If it is the latter, then (0,0) might be a singularity of some kind

Emilio Pisanty

0

I know in quantum mechanics how to represent energy operator in time representation or momentum operator in space representation. I want to know how to represent time operator $\hat t$ in energy representation and position operator $\bf\hat x$ in momentum representation.

quantum-mechanics

Boy is OP in for a rough surprise there

user228700

@JohnR: Hello, good morning :-)

Morning

I wonder why @JohnR pings me ...

The chat must allow abbreviations.

user228700

7:40 AM

It does.

The trouble is that non relativistic quantum, time is a parameter not an operator

I wonder what your name gets abbreviated to. KaH?

@KaH does not ping anything

The abbreivation has to be continuous

Actually now i think about it the text label under the icons at the left does get abbreviated sometimes. Presumably that abbreviation is the allowed one.

No hang on. My name is showing as abbreviated to just John not JohnR ...

@JohnRe also pings you

7:43 AM

Oh well. One of those problems that will have to wait until i really have nothing to do :-)

user228700

Really, any continuous abbreviation pings you.

user228700

Even @Joh would've pinged u had it not been for the other Johns.

You've obviously researched this in one of those anything but more physics revision moments :-)

user228700

@Sec certainly pings Secret (Sorry :-P)

@ka: does this ping you?

user228700

7:47 AM

Nope.

@kau: this?

user228700

@JohnRennie I did no research :-) Just intuition.

user228700

@JohnRennie Yep.

@Ka (nope too short)

Hmm, ka uniquely identifies you i.e. there are no other active users starting ka. Maybe there is a three letter lower limit.

7:48 AM

Unrelated: If you just write @, this name ᔕᖺᘎᕊ pops up

Isn't this fascinating :-)

user228700

@JohnRennie Yeahh, maybe.

I'm currently doing a boring job checking server free disk space, so I've succumbed to the temptation of any distraction :-)

I probably ought to get back to work. Back in a few minutes ...

optics visible-light everyday-life water

What are those servers that you need to manage everyday are doing. Are they part of some supercomputing infrastructure, databases or something else?

(without mentioning anything confidential of course)

user228700

8:10 AM

@JohnRennie Language! :-o (:-P)

Qmechanic

5

Q: Why water has no color?

When a substance absorbs and reflect light,it gives color of that absorbed and reflected light.But water is colorless.Does it absorb and reflect light.What is the reason for this?

61

Q: Why is water clear?

Water appears transparent to visible light, yet most other objects are opaque. Why is that? Is there an explanation why water appears transparent? Is water transparent at all wavelengths, or are the visible wavelengths somehow special? If it is not transparent at all wavelengths, is there som...

optics visible-light everyday-life water

Duplicates?

@Kaumudi.H This project that Bernardo has been given seems stupid. Firstly he wasn't allowed to use C++ but has to use plain C instead, and now he's being told he can't even use the features of C that come closest to C++.

I completely fail to see the point of imposing these restrictions.

@Qmechanic not really. For example copper sulphate solution is clear but not colourless.

Certainly closely related though.

user228700

@JohnRennie Jeez, that's tough.

It seems pointless rather than tough. The code is easy to write, but using features like structs makes it a lot more elegant.

user228700

I meant "tough" as "rough".

user228700

8:17 AM

Should've written rough :-P

The point of setting students projects to do is to teach them something. It isn't clear what this is supposed to teach anyone.

user228700

Hmm :-/

user228700

I've had quite a lot of experience with that stuff in school.

And it should have been made clear what was allowed or not right at the outset. As it is, Bernardo has spent several days on this only to be told his approach isn't allowed, so that's time wasted.

user228700

Wow, that is truly terrible.

8:20 AM

Anyway, I'm going to relax myself by making a coffee - with MY NEW KETTLE :-)

@ACuriousMind If I am to believe Stalin, nah

user228700

@JohnRennie WOKAY! :-)

And for the record it's a beautiful day :-)

Yashas Samaga

I converted a flat earther to a globe earther :D

>implying the earth isn't a cube

user228700

8:50 AM

@JohnRennie :-) That's nice.

@Kaumudi.H The weather or the song - or both? :-)

user228700

@JohnRennie I've just listened to the song and Jesus Christ, that song could not be more opportune :-P

Never mind. Blue skies are on the way!

user228700

Where have I heard that song before?!

That song is from the days of my youth, and it must have been used thousands of times on adverts, films, etc. I'm not surprised you've heard it somewhere.

user228700

8:58 AM

I HAVE HEARD THIS SONG BEFORE AAAH I NEED TO KNOW!!!