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dmckee

02:54

@Arafat I've been told by people who ought to know that it is very hard---perhaps impossible---to identify a photon with a packet of classical EM waves.

3 hours later…

Brandon Enright

05:57

Looks like @JohnRennie will cross 100k rep tomorrow. Crazy!

John Rennie

06:18

@BrandonEnright: there haven't been that many really interesting questions recently. Well, not really interesting to me. Maybe when the universities restart we'll get a bit more activity.

Brandon Enright

@JohnRennie I've felt like there has been a decrease in interesting questions too but I attributed that to my own knowledge growth.

4 hours later…

Arafat

10:44

@dmckee you are saying that photon is not a packet of classical EM waves. If photon is a packet of probability wave are those probability waves emitted from accelerated charged particle?
Please give me any physics stackexchange link if any or any external link.

ACuriousMind

@Arafat What do you mean, "packet of probability wave"? To every particle you can associate some "wave function" representing its probability to be found in an extent of space by projecting it onto the position basis of the Hilbert space - but that doesn't mean that the particle "is a packet of probability waves".

(On a related note: Has anyone else grown to hate the term wavefunction because it always makes people think of actual waves?)

Danu

11:28

@JohnRennie @BrandonEnright I feel the same way, although the rise of Floris and his everyday-physics magic is quite cool

@ACuriousMind Yes! I also have a sneaking suspicion that this enormous confusion about measurement etc. is mainly due to that damned wave picture.... or perhaps I'm wrong.

Arafat

12:07

By "packet of probability wave" I mean two or more probability waves superimposed to form packets of wave. @ACuriousMind

@ACuriousMind I asked it earlier:

Photons can be considered as a wave packet. A wave packet is superposition of two or several waves. Are these waves physical wave or they are probability wave?
If they are probability waves, can we conclude that charges create fields which are in some sense probabilistic?

Physics Meta

12:52

Q: Can't close question with open bounty?

I just tried to vote to close the question How to measure the energy consumption class of a home appliance? because it is squarely about engineering and not about physics. However, it told me something like "questions with open bounties can't be closed". That seems like a odd rule. A bounty do...

discussion

3 hours later…

David Z

16:01

Chat session time! Anyone here?

Bob

hii

@DavidZ

Danu

not too much to talk about really

I was thinking of making a follow-up to my fairly succesful meta post

David Z

yeah

Danu

trying to flesh out the details (community wiki or not etc)

David Z

There is that one featured meta post about whatever it was

Bob

16:04

i want to take some suggestions

David Z

Q: Closing "Insufficient Effort" questions

Some time ago, John Rennie asked, ...in many cases it looks as if the OP simply can't be bothered to put any effort in. Do we have a policy for closing (or not closing) such questions? The Meta question has received not a downvote (12/0 at time of writing). The answer by Ben Crowell says (e...

discussion featured vote-to-close

@Danu I only really suggest making things CW when you really want them to be collaborative

Danu

@DavidZ I think everybody agrees that the best policy here is downvote+comment

Bob

@DavidZ

David Z

Seems so

Danu

@DavidZ I'm still debating whether CW is a good idea

David Z

16:08

@Bob what were you looking for in particular?

Bob

i am an undergrad and currently having a course in classical mechanics

Danu

There were also some other issues about which topics we pick etc etc, but i'll think about it more later

Bob

and i want to study this topic in deep...

so what can i do to cover most of the topic during this semester...

@DavidZ

David Z

You could take a look at our book recommendation question on classical mechanics

and that might give you some sources to continue with

Bob

@DavidZ

i am following goldstein for now which will be the next level

David Z

16:21

Yeah that's generally thought of as a fairly good one

Danu

oh man oh man I might finally hit the rep cap for once :D :D :D

Phonon

haha

gratz

Danu

16:37

at 190 now, should be possible to get 1-2 more :D

David Z

anyway I guess we can let the chat session trail off for today and reconvene in two weeks

Danu

Yes :)

hwlau

@Danu Now you hit it :)

Danu

Ole! My first time :D

Phonon

hehe

ACuriousMind

16:59

Here I was, thinking how many pages of chat session I would have to read, and it's just this? Also, congrats to the Mortarboard @Danu.

Why is that badge called Mortarboard, anyway?

Phonon

@ACuriousMind probably best question so far today :D

Danu

17:18

@ACuriousMind the mortarboard is the thing you wear on your head whn you graduate, a.k.a. the graduate cap (har har har)

ACuriousMind

@Danu Ahhh...that makes a bit of sense, considering the...punny nature of many badges. ;) I only found the literal translation of mortarboard to German, which is exactly equivalent to a board for mortar, and made no sense at all.

Danu

It's what the cap looks ilke :)

@ACuriousMind do you know any reason why a separable space deserves that name?

ACuriousMind

17:34

@Danu Good question! Answers are here

..and here

There's a lot of French there (which I cannot understand), but it seems even the mathematicians are a bit confused on why especially those spaces are called seperable.

It might also have something to do with the Kolmogorov quotient dividing out "non-separable points" producing a $T_0$ space whose square-integrable functions are actually a Hilbert space one would want to look at

Danu

17:54

I can read the french, @ACuriousMind, thanks :D

it's basically just a shitty name :)

Jim

@Danu everything has to be called something

Would a rose by any other identifier not stimulate a similarly pleasant olfactory response?

Danu

I mean... 'densely countable' would've done just fine

Jim

As a name for a rose? That would be terrible! It's not fine at all

Danu

Hah :)

Jim

Densely countables are red, violets are blue.....

Danu

18:08

whatever happens, I won't separate you

Physics Meta

Q: Why wasn't this question moved or put on hold?

I know this might be unusual since people usually ask the opposite question, but I simply have to ask this. It's about this question: Can a "superhuman" move so fast as to be invisible? I really think that this question belongs on http://cogsci.stackexchange.com/ (maybe http://biology.stackexch...

discussion

4 hours later…

Physics Meta

22:37

Q: Bad Question Warning

I was about to ask a question on the website today when I saw a message saying: "Wait! Some of your past questions have not been well-received, and you're in danger of being blocked from asking any more." However, I have only ever asked 2 questions, one with 3 upvotes and one with 4.