The h Bar

user54412

00:16

@dmckee you're too fast ;) I was just about to flag that post for deletion

dmckee

@ChrisWhite He's splashing them around with wild abandon. So I was deleting in bulk. Also, I've asked the team to craft a content ban

tpg2114

00:30

@dmckee @DavidZ physics.stackexchange.com/review/suggested-edits/21971

dmckee

@tpg2114 Hmmm.thanks for the heads up. Mark such edits as spam.

tpg2114

I did it as vandalism, but I didn't know if that brought it to the mods' attention or not

Some day people might grow up. Some day.

user54412

@tpg2114 cc/ @dmckee this philosophy probably doesn't help that issue

user54412

sigh - the internet

tpg2114

Yeah... like I said, some day people will grow up

And stop trying to circumvent the way things work

user54412

00:40

in other news, @tpg2114 I'll probably be following your lead and doing more hydro sims

tpg2114

@ChrisWhite Welcome to the club!

user54412

i chose a thesis project - roughly, develop a general relativistic MHD code (with radiative transfer!)

user54412

we'll see how far into that goal I get....

tpg2114

I'm trying to find something for you if I can...

There's a guy in our lab who is doing something similar for his thesis, he's in the process of wrapping it up. I'm trying to find his proposal

Downloading it from his home directory... good thing I know the root password... heh

@ChrisWhite Send me an email at tim dot gallagher at gatech.edu and I'll send this along

Replied

user54412

01:30

lol - a gold badge awarded for 10k views, and the OP hasn't been seen since the minute he asked that question

2

user54412

25

Q: Will a hole cut into a metal disk expand or shrink when the disc is heated?

Suppose you take a metal disc and cut a small, circular hole in the center. When you heat the whole thing, will the hole's diameter increase or decrease? and why?

Anonymous

01:59

@tpg2114 Haha, that person has still not stopped putting silly comments against me in the edits... He probably doesn't realise that that edit was to remove my accidental downvtoe.

tpg2114

@DImension10AbhimanyuPS I'm not sure, but trivial edits is probably not the correct way to reverse a vote. You might want to ask the mods, but I would think flagging them is a better approach than trivial edits

Anonymous

@LarryHarson I do agree that David Zaslavasky . has "inversted a lot of time and effort in making this a great site for people interessted in physsics.". However, that is no reason to to stop criticising him for his wrong actions.

tpg2114

@DImension10AbhimanyuPS Criticize actions, not people. That's been discussed many times -- "You are wrong" is not good, "This answer is wrong" is better.

6

dmckee

Last time I knew the consensus about trivial edits to reverse downvotes on the mother meta was along the lines of "well, you shouldn't but no one is going to get really worked up about it either...", so when possible the solution is to make a non-trivial edit incorporating some info from the comments, which is also in keeping with the "comments are ephemeral" ethos.

3

tpg2114

@dmckee I would agree, except based on the comments on the edits, somebody is getting worked up about it... Not that it's a huge problem, but it's annoying to have suggested edits that are vandalism

dmckee

02:10

@tpg2114 Yeah. Starting a edit war in order to reverse a lousy downvote is counterindicated. Likewise rubbing someone on a spot known to be tender.

Eka

Hey b4 asking this question in main SE i want to know whether its the right place to ask this question. "How much accurate is the linear fitting using a software". I have some datas which i linear fitted using OrginLab 8 but when i showed those fitted data to my faculity he was concerned about the accurracy. Can you recommend any other softwares?

tpg2114

@Eka What is the r^2 value of your fit?

dmckee

@Eka That is not really suitable for Physics.SE as we don't do computation questions. On the whole I would say that fitting lines is a well understood problem and the only questions is about what features each fitter has (error weighting, log likelihood versus chi^2 and so on).

tpg2114

@Eka scicomp.stackexchange.com would be the home for it

dmckee

I don't know if they will want to discuss the pros and cons of individual software packages. That kind of thing is iffy on most stacks.

Eka

02:17

@tpg2114 the r^2 is approximately -0.2

tpg2114

@Eka Well, that's problematic for 2 reasons

One, it's negative when it should be between 0 and 1 (it is a squared term after all)

And two, a perfect curve fit is r^2 = 1, while a terrible fit is r^2 = 0

So the closer to 1 you get, the better the fit is. If you are close to 0, it's a sign that linear isn't the right fit for the data

Assuming you pruned outliers appropriately

Eka

@tpg2114 hey thanks a lot for the info :)

tpg2114

en.wikipedia.org/wiki/Coefficient_of_determination

More reading about it if you need a direction to go

And en.wikipedia.org/wiki/Goodness_of_fit also has more information

All of that is independent of the software used

theUg

10:42

I need more votes for an answer. I only have one answer, it looks good, but I would like community confirmation with votes, or comments, other answers:

1

Q: Thermodynamic process when nebula is heated

The basic thermodynamics problem is stated as follows. The nebula contains a very tenuous gas of a given number density (atoms per volume) that is being heated to a given temperature. What is the gas pressure? What are the basic assumptions that should be taken in solving this problem? The...

homework thermodynamics ideal-gas

Anonymous

@tpg2114 You're just getting the literal meaning of what I said, which is useless here. n

Crazy Buddy

12:37

C'mon people... Tell me WHY..!!!

To whoever typed 'why is arwen dying': GOOD. FUCKING. QUESTION.

Well, you can hover on the image....

Anonymous

13:12

@CrazyBuddy I flagged that to get rid of the vulgarities.

Anonymous

...

Crazy Buddy

Ohh... If that hurt you, I'm sorry :P

Anonymous

@CrazyBuddy No, not to get rid of the image; only the vulgarity, it isn't appropriate.

Anonymous

Would you put it in a question title ? , .

Crazy Buddy

What..?? o_O

@DavidZ You really are a moderator... You should teach me ya know :P

(I was really waiting for this, because I expected the same)

Physics Meta

15:00

0

Q: Asking purely physics questions

It has not been many days since I joined this site. I thought of using this as to clarify my doubts while doing problems or increase my knowledge in physics. I put questions and ask just to give me hints on doing them and try my maximum to solve those before posting them here. But my questions al...

discussion down-votes

Crazy Buddy

15:11

-1 for the casual sexism — EnergyNumbers 31 mins ago

Wondering why... Hmm... o_O

ManishEarth

@CrazyBuddy "he" and "his"

Anonymous

@CrazyBuddy "Mother" meta and "guy".

Crazy Buddy

@ManishEarth Meaning? What should I use then? o_O

She & her...?

Anonymous

I agree that that's a silly downvote reason.

ManishEarth

@DImension10AbhimanyuPS He's joking, I think.

Anonymous

15:15

You can use Meta-SO, or MSO, or something , of course.

Anonymous

@ManishEarth No, check the vote counts.

Crazy Buddy

@ManishEarth ahh.... Silly me... :)

Anonymous

There's a +4 -1.

ManishEarth

@DImension10AbhimanyuPS So?

Crazy Buddy

I can't even recognize a joke :D

ManishEarth

15:16

FWIW there's a lot more impetus to being politically correct in other countries.

Anonymous

@ManishEarth So, he really downvoted it.

ManishEarth

And?

A joke downvote. On meta. On a +4 post. No biggie.

Anonymous

@ManishEarth And therefore, he must have downvoted it.

ManishEarth

Such language is considered sexist in certain circles.

Anonymous

Oh, a joke downvote...

Anonymous

15:17

I see what you mean.

ja72

15:29

So what are we supposed to do about insuting comments in a post from the OP. (See physics.stackexchange.com/q/75331/392) ?

ManishEarth

@ja72 flag!

Or ping me in chat

Crazy Buddy

@ja72 Seize him..!!! :)

ja72

@ManishEarth I did a flag a few min ago on needing moderator attention.

ManishEarth

Ah

Crazy Buddy

@ja72 Okay... Then, feel free to come to chat... If mods aren't there, you can get a company for additional flagging :D

(I'm around) :P

ManishEarth

15:32

Well, I'm busy now, so I check the flag queue every few hours or so but a ping will usually get to me

Crazy Buddy

@ManishEarth So, the user has been deleted..!!!??? o_O

@ManishEarth Good policy :)

ManishEarth

I have reasons

Not related to the post itself

Crazy Buddy

Can you speak about this?

ja72

Are the comments going to be deleted?

Crazy Buddy

@ja72 They're deleted..!!! (and he's smoked) :D

ManishEarth

15:33

They should already be gone

ja72

ty

ManishEarth

15:46

What a rule man. You may think I'm selfish because I'm not able to get answers for my question but, there are many others who don't have qualified teachers nearby to clear their doubts. I thought this would be a nice platform. By, allowing homework questions(the one you consider as off-topic) this site would become a large resource of interesting questions which checks students conceptually as well as their problem solving ability. Many others would also benefit by solving other's tricky problems. — Rajath Krishna R 3 mins ago

sigh

Crazy Buddy

I think that explains "why there are very diffuse Indians in SE" :P
(Because, they always come in with a lot of expectations) :D

BTW, the important point there is that "homework questions" doesn't necessarily mean that it's pure physics :)

Anonymous

16:04

testing

Anonymous

...

Anonymous

\begin{test}

Anonymous

text

Anonymous

\end{test}

Anonymous

m

Crazy Buddy

16:06

Unusually, I find a lot of people in h-bar today... Hmm... Do we have any sessions? :P

Anonymous

@ManishEarth And finally this will end up in him saying "It's closed because none of you know how to answer it!".

Anonymous

@CrazyBuddy In 23 hours.

Crazy Buddy

I know :)

Gugg

16:49

@ManishEarth What is the current count of temporarily suspended accounts on Physics SE?

Anonymous

@CrazyBuddy You mean you would write the vulgarity in the hover-text in a questioan title?

Anonymous

What's this recentb outbuirsts in no-wiiork homework questions?

Anonymous

That too all of them with the title "PHysics Numerical" in them? .

Crazy Buddy

@DImension10AbhimanyuPS Nope... I don't write it. It's automatically synced from XKCD :)

(I see a lot of starring around. Hmm...) O_O

Anonymous

@CrazyBuddy Those are from me. Most of them.

Anonymous

17:02

Feed provides unclear question...

Logan M

@Gugg This is easy enough to find with Data SE. I count 3 users suspended to cool down, 4 suspended for voting irregularities, and 1 suspended network-wide (which he requested himself as far as I can tell).

3

Crazy Buddy

@DImension10AbhimanyuPS I know that too :D

Anonymous

@LoganM Who;s the third'? Other than Ron Maimong and Dilaton?

Logan M

@DImension10AbhimanyuPS Neo

Anonymous

@LoganM Oh, yes; , Neo. I forgotm about him. Oh, and by the way, couldq you ggive a link to the data.se script? .

Logan M

17:05

@DImension10AbhimanyuPS I used this one and then checked which of the users are actually suspended.

Anonymous

@LoganM Thanks.

Crazy Buddy

@LoganM What does this network-wide mean?

I mean, what leads to a punishment like that?

Gugg

@LoganM Thanks. Self-requested. Interesting.

Logan M

@CrazyBuddy He's suspended on all sites, not just physics SE. In this case I'm pretty sure he requested it himself, but in general it's a very serious thing that requires the SE devs to get involved. As far as I can tell it's only done in cases where there's abuse across multiple sites.

hwlau

@LoganM I only see 6

Ok, I use another script

Logan M

17:13

I'm sure there's at least 8, though there could be more if they were suspended recently or if they were suspended at 1 rep.

hwlau

That's more than what I thought

Anonymous

How can this user be at 1 rep even if he should have 31?

Crazy Buddy

@LoganM ahh...

Anonymous

5354332221333333332311322322

Logan M

@DImension10AbhimanyuPS Post is CW, so he doesn't get any rep.

There are several cases like that which you just have to ignore.

ManishEarth

17:15

Uh, don't clutter the star board :s

Crazy Buddy

I think I'm sleepy... I see stars appear & disappear over Logan M ;-)

Anonymous

How much reputation does one need to make a CW question? The priveleiges page doesn;t mention' it.

Gugg

@ManishEarth What is the "hollow" star on top about?

ManishEarth

@Gugg Pinned

Logan M

@DImension10AbhimanyuPS CW questions can't be made except by moderators anymore.

2

Crazy Buddy

17:17

@DImension10AbhimanyuPS No thing :)

Anonymous

My stars disappeared??????!

Crazy Buddy

They should have some for editing though...

@DImension10AbhimanyuPS Now, I can see the most of them disappeared :)

Anonymous

@LoganM I see, since this post was made CW by Noldorin (with 2751 rep, some how the same, as Dilaton's user id.), but it was in 2010...

Gugg

If a star is very far off, it will not be less visible, but only visible intermittently, right? Is that what is happening?

Anonymous

@ManishEarth: I know you can't give a full reason for the suspension of users, but can you at least tell us whether Ron Maimon was suspended again for his recent comments or the ones before his previous suspension ?

ManishEarth

17:21

Obviously for his recent activity.

Gugg

It wasn't a "cold case" then.

ManishEarth

We don't suspend for actions before a previous suspension, unless said action is much more severe than the reason behind the suspension

Anonymous

@ManishEarth But he hardly participates on the site anymore; comments on his own post?

Crazy Buddy

@Gugg Hey... Only frogs see that. We've blind spots very far :)

ManishEarth

@DImension10AbhimanyuPS So?

Keyword: "Hardly"

Gugg

17:23

@CrazyBuddy Yeah, I just read about that today. :)

ManishEarth

That's all I can tell you.

Crazy Buddy

@Gugg Evidence for photons bumping you --> blip, blip, blip :D

Gugg

@CrazyBuddy I can't keep track of the user names. Did you recommend The Particle at the End of the Universe to me?

Anonymous

I've fully used my vote allowance from the day, no! : )

Anonymous

6

A: What happened to David John Candlin?

I googled a little bit a while ago, and found him. I didn't get any insights into the history of this discovery, he didn't respond to my email. The person I contacted in order to reach him was eventually so offended by my rude email questions that he told me to buzz off. I am only posting this be...

Anonymous

17:25

@ManishEarth Related to this:

Anonymous

?

Crazy Buddy

@Gugg Actually, it was Chris... So, have you completed it? :D

ManishEarth

@DImension10AbhimanyuPS All. I. Can. Tell. You.

Gugg

@CrazyBuddy About halfway.

Crazy Buddy

@Gugg So.... How's it? Can you provide a critic's review? ;-)

Gugg

17:26

@CrazyBuddy And then The Shape of Inner Space. Looking forward to it.

Crazy Buddy

@Gugg Hmm... I'll search it -_-

Anonymous

@ManishEarth The first vversion of your comment seems to indicate a yes...

ManishEarth

@DImension10AbhimanyuPS Huh? No, I was saying that I can't tell you anything more.

Gugg

@CrazyBuddy I'm not a critic, just a reader. I like it. Feels like I'm learning something.

ManishEarth

Because that would involve a specific comment on the situation.

hwlau

17:27

@Gugg Probably you need 10 photon in 1/15s to trigger a blip signal from your retina neuron

ManishEarth

Your previous question could be answered with something that applied to all suspensions.

Crazy Buddy

@Gugg ahh... I didn't know that :P

Anonymous

@ManishEarth Ok...

Anonymous

@Gugg That's a nice way to avoid trouble of having to review a book : ) .

Gugg

@ManishEarth So, the strategy is to provide lots of abuse or other "wrongs" in code, then get suspended for something else, and then, after being "reinstated", provide the key to the code.

Anonymous

17:31

I'll star that once I get more vote allowance tomorrow.

ManishEarth

@Gugg lolwut?

Anonymous

4 mins ago, by Gugg

@CrazyBuddy I'm not a critic, just a reader. I like it. Feels like I'm learning something.

Gugg

@ManishEarth Just a strategy around your policy.

Anonymous

@Gugg Are you sure you didn't meean to @ Crazy Buddy? I don't see how retiina neurons and A particle at the end of the universe is related to suspensions???

Gugg

@DImension10AbhimanyuPS I think I got it right.

Anonymous

17:38

For some reason, Data.SE thinks I'm someone called "jon.doe11482".

Gugg

@CrazyBuddy If I find something wrong or unclear, I'll make sure to ask about it on the main site, as I've done before. But first I want to see how it ends. See if the butler did it.

hwlau

19:12

@LoganM Whats up with Dilaton

Logan M

19:37

@hwlau He got suspended on Physics. Since that was his parent site he can't chat either until the suspension is lifted. According to him on Lubos' blog he got the following message when he was suspended.

Hello,

I'm writing in reference to your Physics Stack Exchange account:

http://physics.stackexchange.c...

Despite multiple warnings
against it, we've noticed that you continue to make inappropriate,
unfounded accusations against moderators and other site members. For
that reason, the moderators are suspending your account for 120 days.

Regards,

David Z

Physics Stack Exchange moderator

Mods here won't discuss suspensions with other users (SE policy doesn't allow mods to discuss suspensions unless they have the permission of the suspended user) so there's no real way to verify that this is even the right message or why he was suspended.

hwlau

@LoganM ic.

Do you think that it is appropriate to post whole content directly here?

And is it only the site moderators?

I think there is a way for them to discuss before suspend

Logan M

Maybe that post was too long. I thought it was going to compress it. I can't edit it anymore so if a mod wants to delete it go ahead.

@hwlau I don't know what happened. If they followed the normal protocol he'd usually be given warnings before being suspended for the first time. I don't think this is the first time though since it's a 4-month suspension.

hwlau

@LoganM I remember his was warning somewhere here last Dec, but I think it is fine for him after that...

"doesn't allow mods to discuss suspensions unless they have the permission of the suspended user" I would think some users want them to discuss

rather than say nothing.

Logan M

@hwlau IIRC if they have the permission of the suspended user, they are allowed, but not required, to discuss the details of the suspension.

If the mods here take the stance that they're not going to ever discuss the details of suspensions in public, that's their decision.

hwlau

@LoganM ok, I almost never see mod discuss these publicly. Probably avoid further arguing.

Logan M

19:50

Anyway all I know is what he's posted on TRF. With just that information and without knowing what mods can see I can't make any educated statements about whether the suspension was justified, if it could have been avoided, etc. According to him he's already contacted SE devs to check and possibly challenge the suspension, so if anything was done wrong (not that I necessarily think it was) it should be corrected.

hwlau

It seems that he doesn't know the exact reason of suspension, a bit surprise.

David Z

20:27

FYI my personal policy regarding suspensions is not to discuss specific cases at all, with or without permission of the suspended user.

Global SE policy doesn't require, but does allow, us to take that stance.

Asphir Dom

21:25

actually is dilaton user same as lubosh motl?

Larry Harson

21:41

@LoganM users are given plenty of warning beforehand to modify their behaviour before being suspended. You also need to ask yourself whether a user has been suspended in the past.

Logan M

21:51

@LarryHarson Yes, this is how it is supposed to happen, and it's probably how it happened. I don't have any evidence to support that anything was handled differently in this case, but it's also not something that I can confirm personally. I also don't know Dilaton's suspension history.

In reality, I don't really care about any of these either. These are things that I don't know and don't really care to know and this site isn't one I'm so active on anyway.

I guess people think that because I've been talking with him I support him universally, but that's not really the case. If he was doing things that deserved suspension, it's perfectly acceptable in my opinion for him to get suspended. The only reason I've been talking with him a lot is because we have shared interests that are not related to the reasons he was suspended.

David Z

By the way guys, even just discussing your lack of knowledge about suspensions like this can subtly lead other people to ask questions that they're not equipped to answer, and that in turn leads to facts being made up. (Not that I'm saying you're making anything up, but as I'm sure you know, there are people out there who would.) That's why I ask (but don't require) that community members also refrain from discussing specific suspensions.

3

As you know, if someone suspects that a suspension was inappropriate, that's okay, but instead of speculating in public and deciding based on partial information, they should take their concerns to the people who do have access to the relevant information to make that decision, i.e. the SE community team.

Larry Harson

@DavidZ yeah, not mentioning names is the key, and keeping it general.

Logan M

@DavidZ That's reasonable to me. I don't really have any intent or desire to continue the discussion here anyway, and I've already said more than I care to say about it. Questions like this are better dealt with by moderators and the community team, not individual users.

David Z

Yeah, I was really just throwing that out there in general. (I appreciate your restraint!)

Larry Harson

22:08

@LoganM it's OK to ask about suspensions in general. Of the nearly three years I've been here, I've only come across three high-profile users getting suspensions varying between a day and one year, and I felt they were fair. I've probably had less than 10 comment deleted over this time, and rarely warned about my behaviour. So it's serious to even be suspended for a day here.

Mostafa

22:31

@DavidZ Do you think the homework tag applies for this question or not?: physics.stackexchange.com/questions/75367/…

I added the tag but the OP removed it.

David Z

23:39

@Mostafa It definitely does. Although the question was also a no-effort homework question so it goes on hold. If it gets reopened it should have the homework tag at that time, but if it winds up closed (because the OP doesn't feel inclined to improve it) then it doesn't really matter.

Andreas Bonini

hey guys this question is probably too basic to post on the main site, but I'm studying for a test and it asks:

The power needed for a lift of 500 kg to go up 10 meters in 50 seconds is approximately: .... and then there is the list of answers

The correct one is 1,000 W, but I can't figure out why or what formula to use, if anyone can help me out it's appreciated

Transcript for