The h Bar

Hari Prasad

7:04 AM

@JohnRennie What are firewalls in blackholes?

John Rennie

@KaumudiHarikumar I read two to three books a week :-)

Hari Prasad

@JohnRennie Real books or PDFs?

John Rennie

@HariPrasad I've only read the descriptions of the firewall idea in the scientific magazines like New Scientist, so I probably don't know any more about the firewall theory than you do.

@HariPrasad I almost exclusively read e-Books these days. Typically in epub format on an Android tablet.

Hari Prasad

@JohnRennie Can you suggest one for me?

John Rennie

@HariPrasad one what? Book or tablet?

user228700

7:09 AM

@JohnRennie :-) That sounds awesome.

user228700

Sir, I was reading the transcript of our conversation regarding Le Chatelier's principle last night, because I spent the whole morning trying to understand enthalpy and free energy and all, and I came upon this statement that u had made:

user228700

"As a rough guide if you increase the pressure you will increase the free energy of the right side more than you increase the free energy of the left side, so the $\Delta G$ for the reaction decreases."

Secret

To meta post people: I am sorry that the meta post have created so much unexpected pitchforking due to me getting a bit overboard when writing about it (details to be described later) and thus it looks more like a rally or protest or something. Thanks for fixing it so it looks more neutral. I will respond and fill in the missing gaps in the chat conversasions in a few moments

Hari Prasad

@JohnRennie Book.

user228700

How does an increase in pressure increase the free energy..?

John Rennie

7:12 AM

@HariPrasad I can't really because I don't know what sort of science fiction you like. I go to a science fiction book club and we've just read The Girl with All the Gifts by M. R. Carey.

Everyone liked the book, so I'm guessing you probably would too.

user228700

@JohnRennie Oh, that's what u meant by SFF meeting? Ah, I thought it had something to do with Church lol :P

Hari Prasad

@JohnRennie Thank you Sir. I'll try that.

John Rennie

Science Fiction and Fantasy - not especially religious :-)

user228700

@JohnRennie Yeah :P Anyway, do u have any time to answer that..?

John Rennie

My statement was rather vague, we'd need to consider a specific example for it to be more meaningful. A liquid truning into a gas perhaps? That's an example where raising the pressure opposes the process i.e. increasing pressure raises the boiling point.

Hari Prasad

7:16 AM

@JohnRennie Oh that book is going to be made into a movie :D

John Rennie

@HariPrasad the film is apparently pretty good.

Hari Prasad

She Who Brings Gifts.

user228700

@JohnRennie OK..?

John Rennie

@KaumudiHarikumar Do you remember the picture slereah posted? Where it talked about the fact that to make the rabit appear requires displacing the air and that's why there's a PV term in the enthalpy?

user228700

@JohnRennie Yep.

John Rennie

7:19 AM

If you increase the pressure the PV term is going to get bigger

user228700

Oh crap, somehow, my brain told me that the $PV$ term has a negative sign in front of it :/

Balarka Sen

@DanielSank It seems to me you are talking about the Gram determinant.

In which case, yes, that's essential to find volume of a Riemannian manifold: you get a $\sqrt{\det{g}}$ term in the volume form induces by the metric, which you integrate to get the manifold.

user228700

@JohnRennie: OK, so everytime something changes, we try and look at how ∆$G$ changes for this change and then how $K_{eq}$ changes for that and then we decide which direction the reaction shifts to..?

Balarka Sen

But I didn't read all the conversation, so feel free to ignore that if that's not what you wanted.

user116211

@KaumudiHarikumar \Delta...

user116211

7:24 AM

Hey @Hari.

user228700

@MAFIA36790 That's OK :P It works right? How was ur exam?

Hari Prasad

@MAFIA36790 Hey buddy good to see you :D

user116211

@JohnRennie, the congratulatory post is coming....

Balarka Sen

@0celo7 Linear algebra is a necessity. You probably haven't seen much of number theory if you think it's a bunch of party tricks.

Hari Prasad

@MAFIA36790 Where are you now and what are you doing?

user116211

7:27 AM

@KaumudiHarikumar okay. The questions were mostly of thermodynamics unlike I feared those to be of optics.

user116211

@HariPrasad Well, at my house ;)

user116211

Anyways, I'm off for a while for writing that post....

Hari Prasad

@MAFIA36790 NO I mean What kind of degree are you pursuing?

user228700

@HariPrasad Lol :P

Hari Prasad

@KaumudiHarikumar What happened?

user228700

7:29 AM

@HariPrasad No, I'm just chuckling at @MAFIA36790's reply: "Well at my house ;)"

John Rennie

@KaumudiHarikumar Yes

Hari Prasad

@KaumudiHarikumar Ah OK.

user228700

@JohnRennie OK! Now I'm gonna go practice some problems. Thanks for ur help sir! Have a nice day :-)

John Rennie

@MAFIA36790 I'd be inclined not to bother with the congratultory post because I don't see it achieve's anything.

Maybe you could do some work on the data explorer and calculate the total upvotes cast over time and show how this shows the site is getting more popular.

That would be something we could all applaud.

Hari Prasad

@JohnRennie What congratulatory post?

user116211

7:50 AM

@JohnRennie That's humble; but this is more of the first achievement in Physics so there should be a post on this.

user116211

@HariPrasad Majoring in Physics.

Hari Prasad

@MAFIA36790 From where?

user116211

Anyways, I would be busy with my exams; so ....

user116211

@HariPrasad That's a secret ;)

Hari Prasad

@MAFIA36790 Wait from where?

IISC?

user116211

7:52 AM

@HariPrasad No ;P

Hari Prasad

IIST?

IIT?

user116211

Okay: I'm in Calcutta....

Hari Prasad

Kolkata?

user116211

@HariPrasad yep!!

Hari Prasad

Ah got it

user116211

7:52 AM

@HariPrasad Don't say anything, please.

Hari Prasad

Congratulations

I am stuck in Engineering XD

user116211

@HariPrasad okay.

user116211

Which branch?

Hari Prasad

EEE so that I can have some Physics

user116211

@HariPrasad Good!!

Hari Prasad

7:54 AM

After B tech I am going for Msc or Phd

In Physics

@MAFIA36790 I am in an IEEE Computer Society program right now and doing PHP.

Physics Meta

8:10 AM

0

Q: John Rennie, the nerd, crosses the 200k. Congratulations!

That's it! He did it!! John Rennie, on 24-09-2016 became the first man ever in the realms of Phys.SE to reach the summit of 200k! For over five years, he travelled and saved people from the evils of confusion in almost every nook and corner of the kingdom of Physics. And now he has crossed thi...

2

Secret

9:34 AM

12 hours ago, by Emilio Pisanty

@ACuriousMind Honestly, the meta question itself was so byzantine and hard to read that I just left it and went to watch Scrubs clips on youtube

(placeholder)

You are not alone. (Separate thing) It seems in order to handle the issue of my communication problem, not only I need data from a negative control, but also a positive control as well. Previously, conversations between me and ACM in the chat have managed to identify the key factors on why my messages are confusing to some. Now in light of this confusion here, it seems I need to figure out why my messages are also not confusing to some others

There's something very weird in the way I communicate and only just recently by discussing with the h barers this year, that we started to understood it

12 hours ago, by ACuriousMind

"The typical fate of these questions is: D was overlooked, OP wants to clarify D, people lose patience for follow up questions and thus no extra response is given, question was effectively abandoned, result in dissatisfied OP." - Ridiculous accusation, given that I reopened the question as soon as I saw that I had misunderstood the question, which actually the first comment OP addressed to me made clear to me

I have noticed this. While at least to my experience I have seen similar questions suffering this fate (of which I failed to brought out any examples since I have not bookmark those questions), and ACM mentioned about the phenomenon of commenter get tired of OP moving the goalposts, I hastily tied this up to the current question at hand since it so strongly reminds of those past questions I read that did suffer from the fate mentioned above. When

writing the metapost, I was thinking whether this is actually a bit too strong given that the question at hand is, as ACM said, the OP's comment was left not very long ago thus the question can be reopened as the OP's comment made this clear. (Or in other words, too early to say about the fate of this question to be liek those I saw in the past). whereas for those cases I mentioned, it is highly likely that those OP's clarifications are still not clear

however, emotional reasons (to be elaborated) get the better of me and I end up with something that is accusating to this question as quoted above

@EmilioPisanty One possible reason for that might be I got way too overboard about the "raise the awareness" thing, which might result in a very strong tone. Therefore it is true that the metapost is poorly written and I am glad you guys have fixed the post so it looks neutral and still managed to bring out the point

12 hours ago, by ACuriousMind

@DanielSank The "raising awareness" phrasing comes off as pretty arrogant to some, I guess.

12 hours ago, by DanielSank

The post says "Here's a pattern that happens. Let's be aware of it".

12 hours ago, by DanielSank

@ACuriousMind Well that's a damned shame.

12 hours ago, by Emilio Pisanty

@DanielSank a.k.a. "Here is one common way that y'all are doing it wrong, I know how to do it right, here's how you do it"

12 hours ago, by Emilio Pisanty

> The author of the answers and comments must take time to understand why OP is confused. It's not enough to identify one particular (usually the easiest to address) proposition in the chain of logic, say that this proposition is false (and maybe cite stuff) and claimed the question is killed.

12 hours ago, by Emilio Pisanty

I just found the meta post to be so badly constructed that I couldn't make out heads or tails of it, nor did the post communicate clearly to me why I should spend significant amounts of time to puzzle out its byzantine logic

I thought the logic is clear (as I have verified that with someone else that is not me (thus obviously does not have the byzantine logic problem that I am commonly said of), but I agree the whatever strong emotions stemmed form my response to the aim of "raising the awareness" might have made the aim of the meta post poorly elaborated, result in the confusion

12 hours ago, by DanielSank

I find it slightly funny that this meta post got so much flak, while other meta posts we've had over the last few years, which are equally terrible, have gotten lots of answers and upvotes. It's rather interesting to speculate on why that happens.

user228700

10:02 AM

Hello and sorry for interrupting the conversation but if anybody is interested/free, can you please help me with a homework-tsy question?

user228700

I'm facing trouble with integration :/ I will specify the question and my problem in solving it: "A chain of length $L$ and mass $m$ is slowly pulled at constant speed up over the edge of a table by a force parallel to the surface of the table. Assuming there is no friction b/w the table and the chair, calculate the work done by the force till the whole chain is pulled onto the table".

user228700

Since the phrase " pulled *slowly* " is used, I assume no acceleration. Hence, the force, at any given time will equal the weight of the chain hanging. This force isn't constant and is given by $mg(L-x)/L$ where $x$ is the distance the chain has traversed *on* the table. Now, I have to integrate this w.r.t $x$ after multiplication with $x$ but how to do this..? If I consider $F.dx$, I will get integral[${mg(L-dx)/L}.dx}] As u can see, there are *two* $dx$ terms. What is the correct approach and what have I done wrong..? Can anyone please help me?

Secret

$\int\frac{mg(L-x)}{L}dx$

user228700

@Secret But how..?

Secret

You have been given the force of the chain as $F=\frac{mg(L-x)}{L}$, and you are asked the work done as the chain get transverse on the table. Therefore the work done is $W=\int_a^b F dx$ where a and b determine the initial and final position of the chain is on the table, hence this integral integrates the force over the distance travelled

which is the work done to pull the chain across the frictionless table

user228700

10:10 AM

@Secret Well, I wasn't given it, I deduced it in attempt at a solution but OK...

user228700

So I don't need to bring to the form $Fdx$? I do $F.d$ and then integrate it wrt $x$..?

Secret

dx is an infintesimal change in the variable x, therefore if you integrate dx alone over some interval [a,b] you will get x. So for this case integrating F over [a,b] will give you the work done

$\delta W = F dx$ thus $W=\int F dx$

and all you need to plug in is F

user228700

@Secret Oh crap, OK, I see.

user228700

Thanks so much! :-)

Secret

On brief inspection, your force also look sensible because as more and more of the chain is on the table hence $x\rightarrow L$ the force needed to exert tends to zero, which is consistent to what we observed when we actually carry out such experiment

user228700

10:20 AM

@Secret Don't go confusing me now. I'ma do it the way u suggested :P

Secret

Well I have not add anything new, I am just analysing the expression for F you derived

Secret

12 hours ago, by DanielSank

I find it slightly funny that this meta post got so much flak, while other meta posts we've had over the last few years, which are equally terrible, have gotten lots of answers and upvotes. It's rather interesting to speculate on why that happens.

It might have something to do with the tone I wrote it that might have accidentally make it sounds more like a protest of something

12 hours ago, by ACuriousMind

@DanielSank Well, it got flak from me because I felt that it took an honest mistake I made and promptly corrected as soon as I become aware of it and...accused it as being representative of some pattern I could not fully determine what it was.

Well I guess one possibility of this misconception might be because of the poor way I wrote the post. What is actually happening is that we initially thought the question is closed as a duplicate (which on that close banner list out you, Johnrennie and Jon Custer). However from the chat discussion that followed, we are then made aware that there's only one duplicate close vote and the other two votes are unclear close votes instead of all 3 being duplicate votes. (which brought back

to what daniel previously discussed with you and emilo about the close reason lyin problem)

The scenario is made more complicated because of how the pattern of events (the way the question is mistakenly closed, followed by the OP trying to clarify it with every second comment), strongly reminds of the typical fate of those questions I have seen in the past. Thus this strong association result in the two things to become linked up together and result in the confusing take home message that was written in the metapost

And this is made even more confusing because of my failure to have a list of those past questions as evidence ready that point out that pattern i am talking about (which strictly speaking may not apply to that question in the metapost because it is still too early to say the fate of it, as ACM adds how he now understood the OP's comment, made an edit and reopened the question)

12 hours ago, by DanielSank

Perhaps @Secret was pointing to a pattern so that we will be aware of it.

Currently, I can only say this pattern exists (whether it is as widespread as I said, you might have different opinions on it, but the lower bound is that I have seen at least one case in either MSE or PSE roughly per month). However I don't have those questions bookomarked yet (because I am not explicitly aware of them until I decided to make this metapost) thus I am unable to show you. The MSE I quote does illlustrate a simialr phenonmenon but technically speaking have no missinig node problem in it,

12 hours ago, by DanielSank

Note that no usernames were included in the meta post.

It is true, I am not accusing anyone, I am talking about the pattern itself. The identities of who in the pattern does not matter because it is not the full picture

12 hours ago, by ACuriousMind

@DanielSank No - it's fine if there is an overarching pattern that's clearly delineated and shown with evidence.

I will try to test my own claim by keep ing and eye for those questions with that pattern I mentioned about and perhaps that can help clarify it. However the missing node peoblem is now addressed by the metapost, thanks to the latest edit that masisvely tone it down an remove the "typical fate" diversion

12 hours ago, by DanielSank

Because clearly something about the wording has brought out the pitchforks.

12 hours ago, by Emilio Pisanty

@DanielSank Not sure I see the pitchforks

I suspect it might be because 1. The unedited post sounds like it is protesting something, and 2. I mistakenly linked the "typical fate" and the "missing node problem/people misread posts" together due to a very strong emotional reason (to be elaborated)

13 hours ago, by DanielSank

@ACuriousMind Yeah, that's it. The message is "People misread posts. Here's an example of a way that I (Secret) think I see happen with some frequency. Keep this in mind please. Have a nice day."

Yes guys, you are right, This is the main thing I and Danielsank want to made others be aware of in the metapost

Fermi paradox

10:49 AM

Assuming WW3 is about to start, which Geiger counter would you suggest buying?

Secret

Well, i don't see how different geiger counters will make a difference since everywhere is going to be filled with neutron radiation, gamma rays, alpha and beta particles anyway...

Fermi paradox

"Everywhere" is a rather relative term. Not sure if the radiation will spread uniformly. There will be areas not receiving any direct radiation from nuclear blasts. Their problem would be fallout. Which is based on .. luck

Secret

I am not sure then as I am not an expert, but if I were you, I will keep an eye on x ray and gamma levels

since alpha can be avoided easily as long you don't inhale the fallout

Secret

So to summarise, here's what I think that might have caused the pitchforking:

To start off:

yesterday, by DanielSank

@ACuriousMind @JohnRennie I have absolutely no idea why you guys closed this question as a duplicate.

This is our mistake caused by the cloe banner only list one close reason when the voters have different close reasons, aka the Close Lying problem that danielsank pointed out

Based on what I read through all your chat log, i believe the confusion about this is addressed. Now

yesterday, by Secret

(I will let you guys finish before I comment about the typical fate of questions like this. (It is a very common thing for any questions asked on the internet in general))

This message marks the begining of that memory association that the pattern of events by that question reminds me of. As a result my next post is a rather heated emotional statement

yesterday, by Secret

Typical fate of these questions are: D was overlooked, OP want to clarified it is D, people lost patience for follow up questions and thus no extra response followed, question effectively abandoned, disatisfied OP

As you can see it is all bold, thus it is actually very emotionally volatile

yesterday, by DanielSank

The author of the answers and comments must take time to understand why OP is confused. It's not enough to identify one particular proposition in the chain of logic, say that this proposition is false (and maybe cite stuff) and claim victory.

This is our initial draft of the metapost and what danielsank get from our analysis. For this post there is nothing pitchforking risk about it

However, I became extremely emotionally related when I saw these:

yesterday, by DanielSank

@Secret, I am very happy you brought this up. Often when I see these questions I just ignore them because I don't want to deal with explaining to OP that $D$ is the problem.

yesterday, by DanielSank

It's much, much worse when there are already statements by other users saying "NO YOU'RE WRONG BECAUSE B IS FALSE AND EVERYONE KNOWS THAT"

yesterday, by DanielSank

In such cases, I just move on, feeling dissatisfied.

The source of this emotion is as follows:

yesterday, by Secret

For me I don't (because of my extreme hate of unanswered questions). This is why sometimes to professors and others (and even the chat) they thought I seemed to be interrogating them when I ask them questions, because I am guiding them to kill D

Suppose that "typical fate" pattern I mentioned above is actually insignificant, then it is possible my extreme hatred of people unable to answer people's question or unable to get satisficatory answers (in other words, me hate the unexplained) might have cloud my judgement and result in "people missing the point" to become link up with "typical fate" in my mind

Now the trigger message:

yesterday, by DanielSank

@Secret I strongly encourage you to make a meta post about this.

As soon I saw this, the following things are boiling in my mind:

>**FINALLY!, the time has finally come to make everyone clear of this annoying question abandoning problem and people constantly missing the point. Hopefully now with that meta post, we can finally declare war to the incorporeal entity of "unanswered or poorly answered questions" and with this point brought across, all these questions will slowly die and there will be less unclear mess left behind!**

Secret

11:17 AM

So Emilo is probably right about the lording suggestion. I am basically emotionally on hype when writing that metapost, which is why it is so poorly written with the "typical fate" problem get tangled with the "missing the point problem"

Because I knew I am emotionally on hype, and thus chance of distorting thigns without awaring, after the metapost is finsihed, I asked danielsank to double check whether it is still to the point with no distortion. Daniel have made edits to tone it down a bit, but for some reason it still attract a lot of pitchforking

(which until I read the most recent batch of chat log today, I don't thinkg there is any pitchforking, because everyone seemed to be responding quite normally with David Z giving a good suggestion on how to deal with it, and ACM highlighting the importance to put the edits into the question itself to fix the question and not just rely on comments)

Secret

So in conclusion, I am very sorry that my overheated emotions result in that poorly written metapost and I am glad that you guys have fixed it so now it can serve its intented purpose

Perhaps the next time when I decided to write a metapost and awaring that I am too emotionally hyped, I should ask someone else to write it for me instead

Slereah

Secret

Almost forgot: cc @danielsank, @ACuriousMind, @EmilioPisanty, for the massive summary above that hopefully will explain whatever gaps you guys have in the previous discussion while I was asleep

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