The h Bar

12:00 AM

@Danu Ah. Well, there could be something hidden there, but given that quantization works "the wrong way", anyway, I don't think anything deep is hidden in the "symbols of classical observables" -> "quantum observables" maps.

(I would not be surprised if I had to retract that statement someday)

DanielSank

Anyone know how to compute tunneling rates in a bistable potential with damping?

ACuriousMind

::hides::

Stan Shunpike

LOL

Danu

@DanielSank Yaaaaawn... Huh, what?!

DanielSank

I think there's some kind of simple way of doing this with path integrals. A nice pedagogical resource would be much appreciated. I'm particularly interested in getting an answer, whether numerically or otherwise. I don't really need to understand what I'm doing ;-)

Stan Shunpike

12:02 AM

@ACuriousMind I didn't know there was anything you hide from besides @0celo7 's questions about GR

Danu

What's a bistable potential

and what does damping mean in this context

@ACuriousMind I think my above comment shows you should retract it already, but ok

0celo7

@StanShunpike I had a really technical question about connections that he was afraid of earlier.

DanielSank

@Danu One with two local minima.

@Danu I'm not entirely sure how you want me to answer this.

One point of view is that the system is coupled to an infinitely dense set of harmonic oscillators (Caldeira Leggett model). The results of this is that the system experiences decay from higher energy levels to lower energy levels.

Danu

Okay, I don't know or care enough about that to have any form of an answer :P

Stan Shunpike

@0celo7 Not surprised. He doesn't seem to jump for joy at GR questions the way he does others. Although, he usually knows enough to answer mine. That's not saying much though :D

DanielSank

12:05 AM

@Danu Why the yawn?

ACuriousMind

@Danu As beautiful as geometric quantization is, it's still the wrong way for being "fundamental", in my view. Not every quantum system is a quantization.

Danu

@DanielSank It's 2 AM

DanielSank

@ACuriousMind Ha! Thought you could hide, eh?

Stan Shunpike

Good thing Sofia isn't here @Danu She'd spend the next 10 minutes trying to explain to you what a bed time is...

Danu

@ACuriousMind Meh, I'm not sure you can prove this?

ACuriousMind

12:06 AM

@Danu Fermions.

0celo7

#rekt

DanielSank

@ACuriousMind Grrrrr.

@0celo7 LOL

Danu

@ACuriousMind But we can still take a classical limit

I thought that was you meant, apparently not

ACuriousMind

@DanielSank Damn, you caught me. Well, I frankly admit that I've no clue how to do what you want to do :)

Danu

@0celo7 Not really.

DanielSank

12:07 AM

@ACuriousMind Dang.

Danu

@ACuriousMind So what do you mean by this?

ACuriousMind

@Danu Quantization is a map "classical systems"->"quantum system". I don't think it is fundamental because it is not surjective, since fermionic systems, for example, have "empty"/non-physical classical limits.

Only if every quantum system arose as a quantization of a classical one you could convince me that these operator prescriptions really mean something

Danu

@ACuriousMind Fermionic systems have non-physical classical limits? Do you mean something technical here?

DanielSank

@ACuriousMind I agree with this, FWIW.

Danu

Fermionic statistics go to Boltzmann statistics, agreed?

Ah, you're talking about the other direction

dmckee

12:11 AM

Undirected carping:

Danu

In that case, I must ask... Why do you not say bosons?

dmckee

"What is the intuition behind [X]" is too damn easy to say when you mean "I'm to lazy to really think about [X] and want you to try explaining it again."

Danu

@dmckee Agreed. However, it is also sometimes the most important question

dmckee

and I postulate that there is some magic field associated with the first time people hear about relativity that causes them to believe that no one else has ever noticed how weird it is.

7

Danu

@dmckee :D :D :D

dmckee

12:14 AM

Probably QM too.

@Danu Oh yes. The intuition question is important when asked by someone with the right preparation. That's what makes it immune to angry responses and makes it sooooo safe for the lazy.

ACuriousMind

@Danu I say fermions because the only time fermionic (super-Poisson bracket) relations show up in classical mechanics is when you are trying to make gauge theories nice. No "natural" classical phase space coordinate will ever be fermionic

Danu

super-Poisson?

Marcel

@ACuriousMind @Danu: I once heard that geomertic quantization is somewhat similar to the way you get spin out of angular-momentum algebra. One takes the universal covering space subject to that algebra.

Danu

Over-muh-headddd

Marcel

geometric quantisation is somewhat similar to taking the covering space of the symplectic structure

but dont ask me mroe

Danu

12:16 AM

Okay, that sounds interesting

I'm really surprised you dislike it, ACM

ACuriousMind

@Danu I don't...dislike it. I just don't think any quantization procedure is more than a crutch for us who we cannot stop wishing the world is classical.

Marcel

well. my world is classical. haven't notice any other since now. just some books telling me different ^^

Danu

lol

ACuriousMind

@Marcel Never seen the double-slit?

Marcel

I did, and explained it with EM-dynamics ;)

ACuriousMind

12:21 AM

@Danu Yeah. The proper treatment of gauge theories is weird. I've learned a lot about classical gauge theories reading Quantization of gauge systems. Not what I imagined, but it was definitely interesting.

@Marcel Never seen Stern-Gerlach, then^^

Danu

@Marcel Electrodynamics... how exactly? Let's take the single-photon-at-a-time version.

Marcel

EM-dynamics != photons

Danu

Yeah

Marcel

just some intensity pattern that causes reaction

chaotic on low intenstiy

Danu

I mean, the one that is usually explained with QM because there's only one photon at a time

Marcel

12:26 AM

but still the propability is like the density pattern

ACuriousMind

I think that Danu's point is that you can actually do low-intensity measurements when you can see single photons hitting the detector in slow succession.

You can't explain these dots showing up with EM.

Danu

Exactly.

ACuriousMind

You also can't explain the photoelectric effect, for that matter

Danu

Let's do, say, one photon per minute.

Marcel

you can explain that by small (chaotic but deterministc) intensity fluctuations in EM-dynamics

a very small intensity will cause a material system to react on single points since that material system consits of discrete atoms

ACuriousMind

12:30 AM

@Marcel Ah, next problem, stability of electron orbits :P

Marcel

got me there ;) but I'm a bomian. my orbits are stable too ;)

Danu

@Marcel Okay, but this means that you adhere to a theory that experimentally exactly copies the standard QM.

I think this is very strange when looking at your earlier supposed classical explanation

Marcel

photon != elcetron

matter waves != EM-waves

Danu

Haha okay

Have fun with that :) I give up

Marcel

next point in line would be photo-electric effect

ever tryed to just put a harmonic oszillator and see what the maximum velocity depends on (linearly)

ACuriousMind

12:34 AM

And now for something competely different: @Marcel: What's that knubbly thing in your profie picture?

Marcel

right, frequency

RP^2

Danu

PSA: I think everybody gave up on interrogating you

ACuriousMind

There are too many deformed spheres around^^

Marcel

yeah, don't take me seriously btw

I just got that ugly thing from wikipedia

Boy's surface

In geometry, Boy's surface is an immersion of the real projective plane in 3-dimensional space found by Werner Boy in 1901 (he discovered it on assignment from David Hilbert to prove that the projective plane could not be immersed in 3-space). Unlike the Roman surface and the cross-cap, it has no singularities (i.e., pinch-points), but it does self-intersect. Boy's surface is discussed (and illustrated) in Jean-Pierre Petit's Le Topologicon. Boy's surface was first parametrized explicitly by Bernard Morin in 1978. See below for another parametrization, discovered by Rob Kusner and Robert Bryant...

Danu

I think it's related to sphere eversion thing, a.k.a. my previous profile pic

Stan Shunpike

12:42 AM

That looks like a really messed up pacifier or ear.

ACuriousMind

I think I'll change my pic sometime soon again. I'll keep the obscure RPG character theme, though.

Stan Shunpike

You should do the meatbag guy!

the robot man

whatever his name is

ACuriousMind

@StanShunpike Yes, I was thinking of HK-47 :D

0celo7

@ACuriousMind Care to offer some advice? I'm not sure about this fusion he's talking about.

Marcel

well guys, gotta sleep

Danu

12:46 AM

A guy about to win 20k: twitch.tv/pokerstaples

ACuriousMind

@0celo7 He seems to be under the impression that a fast-moving stone will cause the air to fuse with it. I've no idea whether that happens or not, but I think not.

@Marcel n8

0celo7

@ACuriousMind If it does, surely the effect will be negligible, right?

ACuriousMind

@Danu It's been quite long since I last played a good game of poker :(

0celo7

@ACuriousMind You mind commenting somewhere and expressing your doubt on the fusion?

ACuriousMind

@0celo7 How should I know? I'd say it is, but I've got no idea, really.

0celo7

12:50 AM

@Sean A few more points and we won't have to approve your edits :D

Danu

@ACuriousMind He just won the tourney

0celo7

@ACuriousMind What's the time constraint on accepting answers?

ACuriousMind

@0celo7 You can accept an hour after posting, I think, but I'm not sure

@Danu ::tips hat::

Danu

@ACuriousMind I've been watching this guy for quite a long time. Pretty epic. This is the second time he wins this tournament (each time 19.x k) in a month.

0celo7

@ACuriousMind This is his source for the fusion: what-if.xkcd.com/20

what-if.xkcd.com/1

Kyle Kanos

12:58 AM

@DanielSank: I won.

0celo7

@ACuriousMind Should I delete my answer?

@ACuriousMind 41 to go.

ACuriousMind

@0celo7 Uh...if you think it is wrong, yes. I've no idea what's correct here.

0celo7

@ACuriousMind Those links seem a little far-fetched.

I'll leave it unless I get downvoted.

Jimmy360

@0celo7 thinking about it deeply, huh

0celo7

@Jimmy360 You really think fusion will happen on the surface of the stone?

Jimmy360

1:05 AM

bad sources, I know, but xkcd has always seemed to use legitimate science

0celo7

Even if it does, which I'm not sure if it will or will not, the effect should be negligible.

Jimmy360

and in what-if.xkcd.com/1 it hapened on a baseball

0celo7

@Jimmy360 I'm skeptical at Mr. xkcd throwing around "fusion" without any sources or proof.

@Jimmy360 If you get a better answer, I'll remove mine.

Jimmy360

Even if it is negligible, I calculation or good estimation on the added output caused by it would be appreciated

ACuriousMind

@0celo7 He did link a paper for the meteor one (I haven't checked it)

0celo7

1:09 AM

@ACuriousMind I see a simulator, not a paper.

Regardless, my answer is probably a decent start.

ACuriousMind

@0celo7 I meant this link, but as I said, I really don't know anything here.

0celo7

OH

Jimmy360

@0celo7 your answer is excellent, but I want the answer to account for the fusion

0celo7

@Jimmy360 Huh, I have to read that paper!

Jimmy360

awww, I hate it when you have to pay

wait, you have

0celo7

1:12 AM

@Jimmy360 Piracy mane math.uwaterloo.ca/~sdalessi/Tunguska.pdf

Thank you kind stranger who is repping me like crazy.

@ACuriousMind I'm #12 in rep gained this year!

I beat Jim and Chris today.

ACuriousMind

@0celo7 I see the gamification has got you :D

0celo7

1 more!!!

C'mon!!

That's so sad.

Jimmy360

ill get ya

there you go

0celo7

@Jimmy360 Noice!!

Jimmy360

because your answer is good

ACuriousMind

1:19 AM

@0celo7 Cute ;)

0celo7

@ACuriousMind Now how do I ban fools??

Jimmy360

XD

ACuriousMind

@0celo7 lol

We can't do that

Jimmy360

I'm scared. I might need to take that back.

ACuriousMind

We have to rage at the (seemingly) ineffectual power of closing a question 20%

0celo7

1:20 AM

...

THAT's what I worked for???

...I...have to overtake Lubos.

ACuriousMind

@0celo7 Well, you can always hope to be elected moderator :P

@0celo7 Then John is still ahead of you

0celo7

@ACuriousMind Pretty good for a 17 year old, no?

ACuriousMind

@0celo7 Certainly, you'd have had no fun with 17-years-old me

abt

@ACuriousMind you did not read a lot back then?

0celo7

@Jimmy360 Wait, it doesn't fuse after all??

John Rennie's rep is just ridiculous.

Every answer gets points.

ACuriousMind

1:24 AM

@abt I have always read a lot, but fiction. Everyone of the 17-years-olds here surpasses what I knew of physics back then by far

0celo7

@ACuriousMind Still, how do I VTC someone's hopes and dreams?

@ACuriousMind How many of us are there?

Regular users, that is.

I know of myself, Jamal, abt, HDE...

ACuriousMind

@0celo7 There should be a new close link between edit and flag.

abt

@0celo7 Visceral Toxicosis of Catfish?

0celo7

@abt Viscous Tenacious Catfish

@ACuriousMind You now have a gun, point it.

ACuriousMind

@0celo7 I don't know of any others off the top of my head

abt

1:28 AM

I know someone.

user: GRrocks

Jimmy360

@0celo7 at very high speeds 99.9% and up, it doesn't fuse

0celo7

@Jimmy360 It says that in the article? (Haven't read it yet)

ACuriousMind

@0celo7 I don't tell others what to VTC unless I'm out of votes.

0celo7

@ACuriousMind I have all this power now, I can't just not use it.

abt

close my question

its so bad it's humiliating

please

ACuriousMind

1:30 AM

@0celo7 Then visit the close vote queue!

0celo7

@ACuriousMind where the heck is that??

Jimmy360

it says that in a lesser source what-if.xkcd.com/20

@0celo7 physics.stackexchange.com/review

ACuriousMind

0celo7

@ACuriousMind So how many of these things do I have?

@ACuriousMind wow no need to show us your rep

ACuriousMind

Click the review button next to help

0celo7

1:32 AM

We all know you have a BBC e-peen :P

ACuriousMind

And you have 24 close votes per UTC day

0celo7

@ACuriousMind do we generally VTC on questions that should be migrated?

abt

wait so you cannot delete questions?

0celo7

@abt No that's 20,000?

Jimmy360

you can only close them

abt

1:33 AM

too bad

0celo7

vote to close

Kyle Kanos

@abt 15k rep can vote to delete after 1+ days for a closed question with no upvoted answers

ACuriousMind

@0celo7 If you think they don't belong here, yes. But if you merely think they'd be better somewhere else, then no.

Jimmy360

there have been too many "could dark matter/energy be" questions lately

ACuriousMind

You can directly vote for something to be migrated to math.SE, but all other things you just VTC with a custom reason.

0celo7

1:35 AM

Well this is...underwhelming.

@ACuriousMind You and the others got me all fired up for a VTC fest.

ACuriousMind

@0celo7 Huh? That was really never my intention

Jimmy360

@0celo7 I'm scared now. You seem to want anarchy.

Kyle Kanos

Yeah, not a VTC-fest.

0celo7

@Jimmy360 Crap, I forgot to subtract off the rest mass.

Kyle Kanos

But doing work to keeping the site clean of HW-type questions

0celo7

1:36 AM

That explains why my numbers are funky.

ACuriousMind

But you need to use these votes, because we have not enough regular reviewers, in my opinion.

Jimmy360

@0celo7 and you put c instead of c^2

0celo7

@Jimmy360 Lol, crap.

abt

indefinite suspension...

ACuriousMind

@KyleKanos This. Most other off-topic types are not that much of a problem, but even the most obvious HW-like questions take quite long to be closed.

abt

1:39 AM

when does the "year" cycle reset for rep?

Kyle Kanos

@ACuriousMind I wish the golden ban-hammer worked for not-dupes

I'd totally get it just to slam shut all the HW q's

@abt huh?

ACuriousMind

@KyleKanos Then we would still only have John to bash the GR questions, because Lubos doesn't do voting.

@abt Aptly, at 01.01.YEAR

abt

@0celo7 you started answering at the best time.

0celo7

@Jimmy360 Fixed it.

Jimmy360

@0celo7 I might have to take that upvote back if you don't correct your mistakes...

0celo7

1:42 AM

That was really bad.

Jimmy360

bringing you below 3000

0celo7

@Jimmy360 I'll get it back.

Jimmy360

@0celo7 I was bluffing anyway. My upvote is locked.

0celo7

Huh?

It's fixed now, at least I hope.

abt

they should implement titles.

0celo7

1:44 AM

Well I'm off for tonight.

ACuriousMind

Btw, I still encourage people to bring good (especially experimental) questions to my attention so I can bounty them.

0celo7

@abt i.e. "Padawan" for high schoolers?

abt

@0celo7 perhaps?

0celo7

@ACuriousMind I've got a neat string theory question here that might be of interest.

Jimmy360

@ACuriousMind A bounty would get my question so many answers... but unfortunately my question isn't bounty worthy.

0celo7

1:46 AM

It's about strings.

abt

wait 0celo7 you should try to get as much rep as possible before you turn 18 yrs.

ACuriousMind

@0celo7 Heh, I'm not gonna bounty that again for at least ~1month

0celo7

@ACuriousMind We need Danu to interrogate Gerard.

ACuriousMind

It seems everyone either doesn't know what 't Hooft means or has very weird and handwavy ideas about it.

DanielSank

@KyleKanos Congradulations, Dr. Kanos.

ACuriousMind

1:48 AM

(or considers it so trivial that it's not worth answering)

Jimmy360

If I attain at this rate, when I'm 18 I will have 336000 rep

0celo7

@ACuriousMind Einstein the cat has finally worked up the courage to kill and eat spiders...I now have a ninja exterminator that doubles as a vibrator.

Jimmy360

of course, the rate probably will not stay constant

Kyle Kanos

@DanielSank Thank you

0celo7

@Jimmy360 Wow, you're 13?

ACuriousMind

1:49 AM

@0celo7 Heh, my cat also loved to hunt spiders. Unfortunately, he also smashed everything in his path when hunting them (or insects) :D

Many of my mother's vases have cracks as testament to that fact

Jimmy360

@0celo7 yep

DanielSank

@KyleKanos Shouldn't you be celebrating instead of internetting?

ACuriousMind

Oh, you passed your defense, @KyleKanos? Congratulations!

0celo7

@ACuriousMind Einstein licked up the ants during the Great Ant Crusade of 2015

Kyle Kanos

@DanielSank I did celebrate by going out to eat w/ the wife

0celo7

1:52 AM

I can't imagine that being pleasant.

Kyle Kanos

But I also did (typographical) corrections suggested by one committee member

@ACuriousMind Thank you

Jimmy360

Yes!!!!!!! physics.stackexchange.com/users?tab=newusers

0celo7

@KyleKanos Congrats, now you can use the "because I said so" defense on the internet.

Kyle Kanos

@0celo7 Wait...I could not do that before?

Jimmy360

XD Do it on one of my questions

ACuriousMind

1:53 AM

@0celo7 Ah, my cat loooved to chew on plastic :D I can't imagine that being pleasant, either, but you had to pay attention to not leaving any plastic thing lying around that was small enough to be swallowed by a cat.

0celo7

@ACuriousMind Straumann has bite marks.

ACuriousMind

nice^^

I long for the day I live in a place where I can have a cat again

0celo7

My cat also bullies my dog. The dog is submissive to the cat so we have to lock him away when feeding the dog.

abt

I just have a fish.

I feed him 3 times a day, and he can do tricks.

ACuriousMind

@0celo7 Einstein seems to be a real boss :P

Kyle Kanos

1:56 AM

My kids found a frog in the backyard, so now we have Fred the Frog

ACuriousMind

@KyleKanos That's cute :) How old do frogs get?

abt

@ACuriousMind What area of physics do you research in particularly?

Jimmy360

@0celo7 You named your cat Einstein? That is awesome. "Hey, my dog's name is Rex." "My dog's name is Einstein."

ACuriousMind

@abt I'm not really a researcher yet, but my primary interests are gauge theories and non-perturbative QFT.

Kyle Kanos

@ACuriousMind No idea. I know nothing about them

abt

1:59 AM

@KyleKanos if they like frogs, then take them near a pond on a rainy day later in the spring, and if you stand above the elevation of the pond, you will see thousands of frogs escaping out.

it's creepy, i saw it by accident once.

ACuriousMind

I participated in carrying toads across roads when I was really young, it was somehow really fun :D

Jimmy360

To save them or to mess with them?

ACuriousMind

@Jimmy360 To save them. Their "toad migration" often leads them across dangerous roads here in our densely settled region, so there are volunteers who carry the toads safely across these death traps

abt

@ACuriousMind yes exactly I was mentioning that event.

@Jimmy360 what country are you from?

Jimmy360

@abt USA

abt

2:08 AM

are you going to try out for the ipho?

how much do you know btw?

for some reason 0celo7 does not do olympiads.

ACuriousMind

We also got to "catch" tadpoles a few weeks after (just gather them in a net underwater, look at them, and them let them go free again). There really was a significant satisfaction to see the offspring of those you rescued grow up^^

Joshua Lin

2:33 AM

Just a quick question: Is the energy of say a planet orbiting a sun equal to the Kinetic Energy (1/2 m v^2) + Rotational energy (1/2 I omega^2), or is it just the rotational energy? (disregarding the planets rotation about its own axis, just the axis of the sun)

Jimmy360

0

Q: Stone vs. Atomic Bomb

What would do more damage, a B53, a 9 megaton uranium bomb, or a medium sized stone (2 kg) stone throw at 90% the speed of light. One thing that I know that will have to be considered is that fact that at high speeds the air doesn't move out of the way and undergoes fusion with the stone. If the ...

does anyone else want to try answering

ACuriousMind

@JoshuaLin Define "the energy of a planet".

Joshua Lin

@ACuriousMind I guess the amount of work it takes to get it into that state

Jimmy360

0

Q: Stone vs. Atomic Bomb

What would do more damage, a B53, a 9 megaton uranium bomb, or a medium sized stone (2 kg) stone throw at 90% the speed of light. One thing that I know that will have to be considered is that fact that at high speeds the air doesn't move out of the way and undergoes fusion with the stone. If the ...

special-relativity nuclear-physics atomic-physics atoms fusion

come on guys

Icosahedron

3:48 AM

changed my username. initials are too boring.

Jimmy360

Icosahedron

interesting shape

What about Simplex

Stan Shunpike

For anyone who cares about brains, if you can get access, read Towards A Network Theory of Cognition by McIntosh. Its a short article but I found it amazingly summarized with evidence how complex cognition is on a neural level.

Icosahedron

particularly icosahedron is a platonic solid, though the reason i am interested in it dates back many years to when i was little.

Jimmy360

how little

Icosahedron

5 I think.

Jimmy360

3:58 AM

"When I was 5, I was fansnicated by platonic solids." - Wow, we were nerds from birth.

Icosahedron

heh although I think it was more of an aesthetic interest than a mathematical one, I thought it looked pretty cool.

Jimmy360

If anyone wants to take a look, he is a question that I asked. It doesn't seem like it should be right, but I cannot find anything wrong with the argument. physics.stackexchange.com/questions/175019/…

Icosahedron

it doesn't seem to be correct.

Jimmy360

I agree, but I cannot fin what is wrong in my reasoning.

Icosahedron

I think the sum converges to $ \pi^2 / 6 $, the limit approaches to 0.

Stan Shunpike

4:07 AM

Limit of what?

Icosahedron

of coulombs equation as r approaches infinity.

i don't think you should be summing it.

Jimmy360

so would I multiply

Icosahedron

no you would just take the limit

Jimmy360

oh

Icosahedron

$\lim_{r\to\infty} k(Q_1 Q_2)/r^2 = 0$

Jimmy360

4:12 AM

you should put that has an answer

Icosahedron

I decided not to answer any questions on this site until I finish QFT and GR, probably by late fall.

Jimmy360

why

Icosahedron

I don't know.

Jimmy360

...

limits are great

Icosahedron

I want all of my answers to be for hard questions, that is why.

Jimmy360

4:16 AM

some would say I'm obsessed

5 + 5 is approx. the summation 1/n^1.1062

who needs 10

Icosahedron

you are obsessed with limits?

wow that is weird.

Jimmy360

I'm half joking

or am I...

XD

another is dark matter question

Icosahedron

tutorial.math.lamar.edu/pdf/Calculus_Cheat_Sheet_Limits.pdf

study these then? sorry I'm not sure what level you are at, but you should know those limit laws.

Jimmy360

Yes! These laws satisfy my limit cravings.

Your age is also your reputation.

Icosahedron

I only recently turned 17, anyhow I started studying by myself very late.

Jimmy360

4:24 AM

I feel so young around all you 17+ guys.

Icosahedron

There are only a few 17 year old users here, we feel young too compared to the others.

By the way, any high school students here like myself interested in the IPhO?

International Physics Olympiad

The International Physics Olympiad (IPhO) is an annual physics competition for high school students. It is one of the International Science Olympiads. The first IPhO was held in Warsaw, Poland in 1967. Each national delegation is made up of at most five student competitors plus two leaders, selected on a national level. Observers may also accompany a national team. The students compete as individuals, and must sit for intensive theoretical and laboratory examinations. For their efforts the students can be awarded gold, silver, or bronze medals or an honourable mention. The theoretical examination...

Jimmy360

can you start as a freshman

Icosahedron

It's very elementary compared to what goes on here, though it is still hard in terms of solving the problems (to get a gold medal).

Jimmy360

where could one find sample problems?

Icosahedron

ipho.phy.ntnu.edu.tw/problems-and-solutions_5.html

Stan Shunpike

4:35 AM

My mind has been BTFO

Icosahedron

why?

Jimmy360

why?

Icosahedron

because of that neurophysics stuff?

Jimmy360

If it's that great then I will have to find it

Stan Shunpike

A bit. I have known for a while that brains prices using multiple regions at once. But the article I had to read for class...basically did a cognitive task involving using words. And the person had to either respond with mouse click, speak, or think.

And the mechanism they replied with influenced the actual processsing of the words themselves too.

And the authors point was that...we cannot think of brain regions as just having one function. But that everything is always context dependent ans there is much more....distributed activity than you would think.

Its a lot more....probabilistic...but key learning goes on that is measurable by looking at anatomic growth between regions and changes to firing pattern rates.

He did a much better job providing a convincing argument than I am giving. But I just never heard it summarized so neatly before.

Icosahedron

4:39 AM

this might be up your alley en.wikipedia.org/wiki/Implicate_and_explicate_order

"research suggests that memories may not be localized in specific regions of brains"

Stan Shunpike

Cool, I'll check it out. Bohm has a bunch of theories about the mind.

Icosahedron

yeah.

Jimmy360

too many could dark matter be questions lately

0

Q: Is dark matter spacetime with mass?

Dark matter is now understood to fill what would otherwise be considered to be empty space. 'Cosmologists at Penn Weigh Cosmic Filaments and Voids' http://www.upenn.edu/pennnews/news/cosmologists-penn-weigh-cosmic-filaments-and-voids "Dark matter ... permeate[s] all the way to the center of the...

general-relativity cosmology spacetime dark-matter

Ico, technically, you don't have enough rep to talk here.

Stan Shunpike

@Jimmy360 what kind of physics are u into?

Joshua Lin

@Icosahedron I'm going Apho in a couple weeks (apho.phy.ntnu.edu.tw) not sure if I

ll make ipho though

Icosahedron

4:45 AM

Which country?

Joshua Lin

Australia

Icosahedron

ah, good luck.

Joshua Lin

Apho you get to send 8 people, only top 5 make it through to ipho though lol thanks

Jimmy360

@StanShunpike Hard question... there is very little in physics that bores me, but particularly quantum and particle physics are the most interesting to me.

Icosahedron

I cannot participate in Apho because I live in Canada.

@StanShunpike are you in university?

I sort of lost interest in IPhO after meeting 0celo7.

Jimmy360

4:49 AM

what?

how did he make you lose interest

Icosahedron

Rather learn a lot more than to practice for hours on repetitive elementary concepts to get a gold in IPhO.

Jimmy360

Oh no

they are making a chemistry Se

Icosahedron

Though I can still try it next year, I'm in year 11 still.

Jimmy360

this is good for chemistry questions, but many people will take questions like this other there, not knowing that physics SE will be better for it

1

Q: Why some material is waterproof while breathable?

I am an outdoor lover. Sometimes I am addicted to the jackets made of high-tech materials. There are some materials waterproof while breathable, I wonder how this is possible. They(Liquid water and gas water) are water molecures anyway. Is it possible mainly because for liquid water we must cons...

everyday-life

I think that I should stop and appreciate this chat's name for a bit.

Stan Shunpike

5:05 AM

@Icosahedron yeah, just started. First year. Econ major.

But I love physics probably more than anything else (except music :D)

I'm an avid composer. Im working on song 66 right now. I started a couple years ago

@Jimmy360 true, that's like asking one to pick which child you love the most. Hard to do.

Physics Meta

10:01 AM

0

Q: Is there really "no registration required"?

When I am not logged in, I see this on the front page: Sounds good. But when I hit the "ask a question" button, I see this: Isn't that a contradiction? Maybe people find it dubious if there's no registration required yet they have to sign up in order to use the service.

bug new-users

Danu

10:34 AM

@0celo7 you wanted to know what "Russian style" meant right? Here's a nice example from the section on projective geometry in my algebra book:

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