The h Bar

4:14 AM

@ManishEarth I added a comment to the answer. I think it is worthwhile because it entails more than just fluid-dynamics. Although it does actually border on meta-tag status since I can't imagine it being very informative just on it's own.

ManishEarth

8:09 AM

Thanks :)

Crazy Buddy

9:25 AM

@ChrisWhite: Space.SE got MathJax...

And @ManishEarth: Well, you know that... But, did you notice that Space meta also implements Math Jax... o_O

5

A: Writing equations (Mathjax and alternatives)

Nice Job. You put together a good proposal. This has been… $$ \Huge DONE $$

in The Pod Bay, 6 mins ago, by Crazy Buddy

Note the $$ \Huge DONE $$

Crazy Buddy

9:53 AM

0

Q: Humble message to the developers

I'm very happy that MathJax has been implemented in Space.SE. But, what's the necessity for MathJax in Space meta? Was that done by mistake or intended as a purpose? Have a look at Robert Cartino's answer here: Writing equations (Mathjax and alternatives) (P.S. As a Physics.SE user, I got somet...

ManishEarth

@CrazyBuddy Hmm, that's not exactly how you should phrase it :P

Crazy Buddy

@ManishEarth I'm not heroic in these things... That's why I mostly comment & go... :)

You can suggest something (since you can't edit it...) -_-

ManishEarth

Time crystals? Crackpot or mainstream?

Crazy Buddy

@ManishEarth Crackpot..! When we see the word perpetual, we can state the result blindly (as a Physics.SE user) :P

ManishEarth

@CrazyBuddy Really? Close this. I dare you:

3

Q: Quantum perpetual motion

Perpetual motion describes hypothetical machines that operate or produce useful work indefinitely and, more generally, hypothetical machines that produce more work or energy than they consume, whether they might operate indefinitely or not. (Source:Wikipedia) With this definition in mind, p...

quantum-mechanics energy-conservation perpetual-motion

Crazy Buddy

10:07 AM

@ManishEarth Within a few years, I'll close that & dissociate it forever :P

(I'll associate every post of yours to my profile before some daybreak) when you were asleep :)

ManishEarth

@CrazyBuddy Don't you know? I never sleep

Crazy Buddy

@ManishEarth I know... That's in chat... (I'll take control sometime) I won't tell you my secret plan... And, you can in now way hypnotize me :P

Delete everything... Someone's peeking into..!

ManishEarth

10:27 AM

@CrazyBuddy I can use mathematica and hypnotize you

Crazy Buddy

@ManishEarth Your tricks won't work with me... I'm learning Mathematica nowadays :P

But truly, it's very interesting ya know... I've shifted from CAD to Mathematica now ;-)

ManishEarth

cool

Dilaton

10:42 AM

@ManishEarth does the term [aircraft] have an additional meaning apart from this? If no, I really dont understand what it should have to do with fluid-dynamics, and at most question that need it could be engineering or mechanics questions, asking how (parts of) this device work, and it is not a physics keyword at all...

ManishEarth

The physics of flight, right? (which is itself quite a large topic)

@Dilaton In the context of physics, what can you ask about an aircraft?

Most questions about aircraft are engineering, yes

in the context of physics , most aircraft questions will be fluid dynamics

All tags on this site are in the context of physics

Basically, aircraft means "Physics questions about aircraft"

Crazy Buddy

@Dilaton @ManishEarth: Mind both of you-- You too are speaking in front of an aeronautical ~~engineer~~ undergrad :P

Dilaton

@ManishEarth but why would such questions need an additional aircraft tag too? Fluid dynamics, or mechanics if it is more about the engineering part, would be good enough.

ManishEarth

@Dilaton Because the physics of how planes fly is complex

Have a look at these

Crazy Buddy

@Dilaton Because the principles of aircraft combine different fields of Physics...

ManishEarth

10:46 AM

some are engineering, yes. But mostly physics

Crazy Buddy

But, on the other side, it shouldn't go too much...

ManishEarth

Though I guess merging the tag into aerodynamics wouldn't hurt

Crazy Buddy

@Dilaton: For instance, this looks like a decent aircraft question...

2

Q: How does an aeroplane maintain balance during maneuvers?

I understand the principle behind flight, how the lift is generated etc. What I don't understand is when there are maneuvers made where the plane flies such that the wings are in vertical plane, how does the plane not lose its balance? How are the forces acting to keep it steady and from falling?...

fluid-dynamics aerodynamics aircraft

Dilaton

@ManishEarth I dont see the point of introducing and keepind tons of such tags which are not physics keywords physicists would apply. From your POV we would also need tv, train, radio, and tags for each everyday keyword somebody could ask a physics question about :-D

ManishEarth

@Dilaton Are there tons of questions on that tag?

Crazy Buddy

10:50 AM

@Dilaton Radio & TV questions go to electronics + we don't get so much questions...

ManishEarth

@Dilaton The tag isn't a physics keyword... so?

Dilaton

@ManishEarth there are 60 questions at present.

ManishEarth

What makes software a physics keyword?

Crazy Buddy

To complete his point, tags are intended for search queries and not to group or filter questions..!

ManishEarth

What makes lie-algebra a physics keyword?

Questions in those tags are about that keyword in the context of physics

@Dilaton That's a lot

Dilaton

10:52 AM

@CrazyBuddy that is exactly what I mean, questions about rado, TV etc are electronics questions and we do not need to introduce a tag for each of this devices.

Crazy Buddy

@Dilaton You forgot the second point..!

ManishEarth

(except the carrier wave concept which is one question)

@Dilaton Radios are quite simple, and there's not too much physics about them

Crazy Buddy

What I meant there is, if it's too specific - it goes off-topic...

ManishEarth

Aircraft have tons of physics behind the scenes. That's why I pinged tpg on it

Crazy Buddy

That applies to aircraft too...

Anonymous

10:53 AM

@ManishEarth: Why did you remove the bsm tag from 2 posts? It seems relevant to the questions to me .

Dilaton

@ManishEarth software and lie-algebras are things used by physicists in their professional life, aircraft etc are not.

ManishEarth

@Dimension10 If you want the tag, meta post, it seems to be broad. BSM physics covers a lot of ground.

@Dilaton Yes, but the term software in general is not a physics keyword. The tag is software in the context of physics

Crazy Buddy

@Dilaton Ohh.. So, We shouldn't discuss things which has Physics behind it, but things which are used by physicists...???

Anonymous

@ManishEarth Oh, you removed the tag from all the posts with it . . .

ManishEarth

@Dimension10 there were 2

That's not much

Anonymous

10:55 AM

I thought that you removed it because you thought it was irrelevant .

Dilaton

@ManishEarth why did you remove the BSM tag? It should be there for questions adking for example about searches for BSM physics which are more general than just SUSY etc. For particla physics this is a very useful tag and we should definitively have it!

ManishEarth

But to me the BSM tag would basically mean string-theory+other stuff

@Dilaton Would you ever search for BSM or would you always specify which type of BSM physics you want?

Crazy Buddy

@Dilaton If you think you should have, ask it away in meta..! And, you should slow type... lotta mistakes :)

ManishEarth

The reason I removed it was that it's just on two posts right now, and it actually applies to a few hundred

Which means mass retagging

Which means meta post

Anonymous

there was a meta post by ali, I think . . .

Anonymous

10:58 AM

2

Q: Tag Request, Beyond Standard Model

The title sums it well. While Beyond Standard Model is an active area in physics(Check arxiv, there are more than displayable results), we don't have a tag for it. I basically wanted to use it for this post, but I couldn't find anything related to it.

feature-request tags interesting-tags

Anonymous

yup .

Anonymous

but then again, there are other tags .

Anonymous

att least,

Anonymous

if not string theory/lqg

ManishEarth

5

A: Tag Request, Beyond Standard Model

The diversity of possible theories and possible observation that our Beyond the Standard Model (tm) is enormous, and the tag would be so broad that it would provide little characterization of the question. Consider that it is non-unreasonable to consider neutrino oscillation as "beyond the standa...

Anonymous

10:58 AM

,

ManishEarth

Hm, that would be a very broad tag... We have more specific ones for BSM physics topics like supersymmetry, etc for example. To make a new tag while tagging, you can just type in the word followed by enter, to create it. — Dilaton Jul 23 at 8:54

Anonymous

there i s

ManishEarth

Hey, @Dilaton, that's you!! ^

Anonymous

the toe

Dilaton

@ManishEarth yes ST for BSM for example. At the LHC there they do many general BSM physics searches, which are not just focused on ST or SUSY, but includ for example kaluza-klein modes, mini black holes, and many other possible BSM physics effects. At conferences there are often talks about such general searches for example

Anonymous

10:59 AM

lqg

Crazy Buddy

Haha.... Caught the tongue... :D

Anonymous

i mean

Anonymous

qg tags .

ManishEarth

@Dilaton Basically, would you ever search for BSM or would you always search for [string-theory] or [susy] or whatever?

Crazy Buddy

@Dimension10 I don't understand why you always message word by word -_-

ManishEarth

11:00 AM

Anyway, there is a meta post, post your arguments for the tag there

Dilaton

@ManishEarth yes did not see the usefulness of such a tag, but then I agreed with what Matt Reece said:

Anonymous

@CrazyBuddy to ensure that the re aren't a hoarde of messages before mine .

Dilaton

I don't agree and think the context of the OP is exactly the right one where this kind of tag is needed: there's some effect which is not present in the SM and a question about what it means and how it can be interpreted, not linked to any particular model. General things like questions involving bounds on higher-dimension operators---of which the proton charge radius is, more or less, an example---would be a good use of this tag.

Crazy Buddy

@Dimension10 You can edit your own msgs then... Why dump and confuse everyone..??? o_O

Anonymous

or               time limit

Anonymous

11:01 AM

is too short .

Dilaton

@ManishEarth if I want to know what BSM physics effects potentially exist, I would search for BSM, yep

ManishEarth

@Dilaton Hmm

Anonymous

                          "What are the shortcomings of the SM of Part Phys?".

Anonymous

also .

Dilaton

@ManishEarth and I think for filling exactly the gap Matt Reece mentioned, the BSM tag is useful.

Anonymous

11:04 AM

ManishEarth

Sure, note that in your answer there. It's an interesting idea.

Anonymous

1

Q: Magnitude refers to number or number with units?

This question is about terminology for physical quantities. When we talk about magnitude (while talking about scalars and vectors) do we refer to just number or Number along with units? example: If a person weighs 120 pounds, then "120" is the numerical value and "pound" is the unit. Which i...

terminology measurement units

Anonymous

So tempted to put

Anonymous

Research-level tag if

Anonymous

I ever

Anonymous

11:06 AM

get 2000

Anonymous

or whatever .

Dilaton

@Dimension10 :-D

Anonymous

physics.stackexchange.com/questions/tagged/…

Anonymous

Thankfully .

Anonymous

physics.stackexchange.com/questions/tagged/…

Anonymous

11:12 AM

physics.stackexchange.com/questions/tagged/…

Anonymous

This could be tagged as the latter: physics.stackexchange.com/questions/72280/f-ma-in-string-theory .

Dilaton

11:30 AM

@Dimension10 all but the last link point to the Nirvana, the questions seem not to be there...?

@CrazyBuddy well, I did not mean that we should not discuss things which have physics behind it, but we do not need a tag for everything which one can ask physics questions about. Tags should be reserved for physics subfields and physics keywords physicist apply, because Physics SE is about physics and not about the things one can discuss from a physics point of view.

@CrazyBuddy BTW if you think I write many typos when typing too fast, you should see my typos when I am ANGRY , those are really SCAAAARY then ... ;-) :-D :-P

Crazy Buddy

@Dilaton So, you were ignoring my msgs..? :D

(that now you're recalling everything) :P

Dilaton

@CrazyBuddy which one?

In fast chats I have troubles catching everything ...

immediately

Crazy Buddy

@Dilaton See... We have a lot of aircraft questions (which are much concentrated on the ~~mechanics~~ Physics of it), without going deeper into aviation or RC-models or engineering designs...

@Dilaton "not about things one can discuss from physics point of view" Can you clarify that?

We're discussing both things you mention..! There hasn't been anything ruled out on that YET..!

Dilaton

11:45 AM

@CrazyBuddy what do you then mean in this case by the physics of it? I am sure if they are on-topic, there exist physics tags to characterize them such as fluid dyamics or mechanics, etc such that they dont need an additional aircraft tag. It is enough to mention aircraft in the title and/or the body of the question and then attack just the physics tags

Crazy Buddy

@Dilaton Where would you put the questions (asked much) that concentrate on a specific fields... That's what I'm trying to say... There are a lot of questions...

Dilaton

An some additional things one can discuss the physics of it but they need no tag would be train, flute, balloon, etc and I dont think that water and air are that great as tags either, even though many questions are tagged like this.

Crazy Buddy

@Dilaton "Water" and "Air" can be gone.... But, questions on train, flute and balloon aren't much... So, why do we need those? I'd also suggest that "Trains" are more inclined to the Physics side...

Dilaton

@CrazyBuddy for me it would be quite easy to look at the questions tagged by no-physics-keyword and replace them by more physicsy tags we have. Would be a lot of work of course ...

Crazy Buddy

In your point of view, tags like planets, asteroid, sun, star, nebulae, galaxies (and more) can be represented by celestial-body... So, you mean we don't need other things?

Dilaton

11:54 AM

@CrazyBuddy I did mean that we dont need tags named train, ballon, flute, etc

Crazy Buddy

@Dilaton IMO, If the Physics behind something is asked more & more (lot of times), we can create a tag for that...

It shouldn't necessarily have to be Physics-ish...

Dilaton

@CrazyBuddy the tags you now mention are good astrophysics-keywords used by astrophysicists, so they are good.

Crazy Buddy

@Dilaton What about simulation then...? We don't need that? o_O

Dilaton

Maybe I would summarize sun and stars as stellar-physics as the sun is a star too, but they are ok IMO.

Crazy Buddy

@Dilaton But, it can be represented by the celestial-body. That's what you're saying...

Dilaton

11:58 AM

@CrazyBuddy well I guess the physics of stars, and of comets for example are different enough, such that they deserve differet tags.

Crazy Buddy

@Dilaton The same goes to aircraft... Lift, Fluid mechanics, propulsion can't be juggled in different ways to form aircraft's principles... It needs more... ;-)

Dilaton

@Simulation is an important tool for physicists in the same way as perturbative expansions for example. The simulation tag has a bit the issue that the questions have to be physicsy enough and not just ask about how to implement code etc ...

Crazy Buddy

@Dilaton: I know... But, you're still in your circle. Any tag defined in this site should be a tool for physicists or some keyword for physicist. Come out...! It's for PHYSICS :D

Dilaton

@CrazyBuddy do we have lift? This is not a physics keyword either... IMO fluid mechanics and maybe propulsion (slightly engineering but can be ok) are physicsy enough.

@CrazyBuddy :-D? Yes any tag defined should be a keyword, subfield, or method physicists apply is what I mean and said. BTW I am not the only one saying this, other people said the same thing in a meta question concerning tags about two years ago ... just a moment ... have to search for it ...

Crazy Buddy

I leave this here... I don't agree with the last sentence anyway. Maybe someone may respond to that -_-

Dilaton

12:10 PM

... @CrazyBuddy now I have found it... Cedric H expressed the same opinion in a comment below this answer too

I have to go too, spent too much time in chat already ...

ManishEarth

12:40 PM

@Dilaton Just one note: With many of the other tags like train, there aren't (m)any posts on that topic. That makes them unsuitable for now. aricraft has >50 questions, most of them good.

So having aircraft doesn't mean we have to have all the other tags too. The aerodynamics of aircraft, again, is a very large and interesting physics topic

2

> Yes any tag defined should be a keyword, subfield, or method physicists apply is what I mean and said.

See Shog's answer:

Anonymous

@Dilaton I said "Thankfully" because the questions don't exist (kinematics + string theory, etc.)

ManishEarth

> This notion that everything on the site should be lumped into a tiny handful of tags is somewhere between misguided and harmfully stupid.

We don't need to use tagging for just subfields

This is not like arXiv tagging

Anonymous

To summarise, "train, bus, aircraft, flute, table, door, doorknowb, cars, etc." are man-made object s so they don't need a tag . "air, water, hydrochloric-acid" tell you absolutely nothing about the topic. I s it asking for whether air has mass? The chemical compositions of air? Why living organisations need air to seurvive? The number of air molecules + The number of water molecules? Whether air came from a supernova explosion? It says absolutely nothing. Therefore, such tags should be di.

Anonymous

scarded.

Dilaton

@Dimension10 and this kind of tag should also not appear on the first tags page or it would make people think our site is about such man made things instead of about physics ...

Of course not everything should be lumped into (broad) subfield tags (I agree with Shog9 concerning this), but the tags we have should still be keywords meaningful for physicists (concepts, theories, methods used by physicists, etc) and not just man made things and everyday language terms.

Crazy Buddy

1:19 PM

@ManishEarth: Ready to answer something..?? ;-)

So, I was thinking... Imagine some snooker ball moving at 1000 m/s in a direction. A piston-like structure (the face-plate is around 1 cm diameter) and arranged exactly perpendicular to the the ball's direction

The ball crosses the piston's field-of-hit within $10^{-5}\ s$

But, my piston is quite clever and it's so much accurate to a precision of about a microsecond..

If the piston manages to hit a ball with some speed, say 1200 m/s (at exactly right angles), that the force doesn't add any speed to the ball, but just changes the direction...

Common sense suggests that the ball moves exactly perpendicular after impact... ;-)

But, this scene is totally against my intuition... :D

I can't really visualize the scene. That's why I don't get a stable answer -_-

(What about a comic statement - the ball is moving at 6 'o clock while the piston smashes it from 9 'o clock) :P

ManishEarth

1:51 PM

@Dilaton Again, how do you know that aircraft is not a keyword meaningful to physicists?

It probably is meaningful to those in fluid dynamics

And other such fields

Crazy Buddy

^~^

Crazy Buddy

2:30 PM

arxiv.org/abs/1308.1292

People are going crazy... (John Rennie's link)

Anonymous

2:46 PM

physics.stackexchange.com/review/suggested-edits/21183

Anonymous

                                                      @Bernhard:

Anonymous

It's

Anonymous

actually

Anonymous

2

Anonymous

. . .

Physics Meta

3:32 PM

-1

Q: Flags and technical innacuracies

Why can't flags indicate technical innacuracies? Given the large number of upvoted wrong answers (e.g. Is time continuous? (totally fails to understand QM), What experiment would disprove string theory? (totally fails to understand falsification), What experiment would disprove string theory? ...

feature-request answers flagging

Physics Meta

5:38 PM

0

Q: How do I flag a comment I've accidentally upvoted?

I tried to flag a comment, but accidentally upvoted it, and I can't remove the upvote because I have only 1 minute to remove it, which I've only recently discovered. How do I flag a comment I've accidentally upvoted?

support

Crazy Buddy

8:11 PM

@ManishEarth: I won't let you live... until you see my ping ;-)

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