@ManishEarth You're right that allowing JS to be inserted by users is asking for trouble but I thought there was a chance that since the topic can only be set by moderators, it would be allowed.

@DavidZ Can't you cast non-unilateral VTC? I figured you have the option to VTC with mod powers or normal users powers.

@BrandonEnright Nope. Moderators can only close questions unilaterally.

Same goes for reopening, deleting, undeleting, and spam/offensive flagging.

Anyone here familiarize with QFT? I have a basic question. Considering the case of having a system of boson that can be created and annihilated, and suppose we know the mean number of boson <N>, then we can calculate the mean <E> and variance of energy due to the quantum fluctuation. But if the number of boson is fixed N, then is the total energy of the system really constant? (neglecting the uncertainty principle of course)

@BrandonEnright Yeah... That was twice addressed by @ChrisWhite - here & here :)

Okay... Chatjax now copy-pasta from Math meta :D

@CrazyBuddy Damn that second answer is really good.

Yeah, that was the first answer to clarify the whole topic in our site, I guess :D

@hwlau It really depends on exact state of quantum system. If $H \psi = E \psi$, than energy has certain value. Otherwise, you have system like one-particle wave-packet, that has certain value of N(=1), but energy has nonzero width(it is superposition of one-particle states with close enough, but not completely equal energies)

can u please help by answering a question on absorption spectroscopy??

we get absorption spectra because molecule jumps from lower energy state to the higher energy state, and therefore we get a corresponding decrement in intensity at that frequency of the exciting light. But my question is the molecule at the higher energy state will immediately jump to the lower energy state and thereby there should not be any decrement of intensity at that frequency?

youtube.com/watch?v=hW7DW9NIO9M Can someone watch this video and help me out with the equation?

It's hard to explain in messages

anyone?

But, I "hope" at least one of the 8 would be interesting and has the ability to convince me -_-

@Vladimir Thanks, you already answer my question. I am reading stuff on ground state of BEC. After a Hartree and a bunch of mathematical approximation, I get mess up with the interpreting the results.

@user22180 Not necessary. It usually (a) not reemitt immediately (b) emit in all directions, not only originally one (c) the remission pass through multiple state, thereby frequency changed.

@CrazyBuddy Can't you choose different courses youself, so that you can avoid some bad "species" lecturers ?

@hwlau The Indian higher education system is much less liberal than its American counterpart

You can take electives, but in most cases you have a fixed course plan. I'm more fortunate than others, the course plan for me gets liberal as the semester passes by (the fourth year is almost completely a choice-based thing as long as we take a good number of core physics courses, though which ones we take is up to us)

Random animation I made while learning a new software.

^ Now, of course, I'm going to spend hours playing with xcrysden's animation feature, instead of moving on to the next step :P

garr, SE's upload limit won't let the entire gif load

hi @ManishEarth

hey :)

this past 2 months have been hell on earth

am evaluating my continued involvement on a couple of sites

@Scrooge hope it gets better now :)

doesn't matter really, may be leaving these sites soon

@ManishEarth?

Hm?

Sorry, was doing some work

You're leaving? :/

It's your decision though, won't pester you about it

well not all sites, but quite a few - already have left Info Security

i have not posted on Astro or Space for a while

I know astronomy questions can be asked here

@ManishEarth what you working on?

@Scrooge Currently, trying to learn the ropes of Quantum Espresso (it's a quantum chemistry/solid state physics software)

I was using abinit but it was inefficient in some cases and I want to improve

hmmmm intriguing

other than majorly thinning out my memberships on here, I am writin a couple more apps

nice

can't decide whether to stay or leave astro

@ManishEarth I am, at this stage, definitely keeping Academia, Physics, Chemistry and of course MSO and A51... just not sure about Astro

@Scrooge Oh, good :)

is it just me, or has astro slowed

Well, just because you aren't participating in Astro right now doesn't mean you need to delete your account. Most of my SE participation is sporadic

@Scrooge Not really been on Astro for a while, things have gotten busy for me

Most beta sites have a slow period

Not sure if astro is going through it right now though

i am deleting biology and space, and have already deleted info sec

i'll stop disturbing you

@ManishEarth You were studying at a India university?

@hwlau I am currently

Ops, I didn't notice that before

@Scrooge Why do you need to delete an accout to leave a site? Just dont visit them if you have no time

@Scrooge There are less people visit Astro now. It was more than 150/day at the peak a month ago, but now there is less 100/day

@hwlau long and boring story