Physics chat session 2016-04-05

David Z

Apr 5, 2016 16:01

Glad you asked! Welcome to our biweekly chat session, everyone. This is a time when a bunch of people get together in the chat room to discuss stuff.

John Rennie

OK. I have a spacetime diagram in the NMT's frame with the origin at the NMT's position at the year 2010. In this frame the trajectory of the NMT is the vertical line x=0. In this frame the trajectory of the Earth is the vertical line x=-10.

David Z

It's not very fancy :-P

barrycarter

Crap, we'll have to stop for this chat or move to another room @JohnRennie

@0celo7 If you're an engineer, you're not a mathematician :P

David Z

@barrycarter yeah, if you wouldn't mind. Feel free to just put it on hold until we get to open discussion.

I want to try something new this time: we're going to have an agenda, which is pinned in the sidebar.

I'll copy the post here too:

59 mins ago, by David Z

Agenda for the chat session (w/ appx time caps):

1. Intro, welcome newcomers, take policy questions (10m)
2. Recent physics developments (5m)
3. Chat bot for the h Bar @MAFIA36790 (5m)
4. Canonical relativity answers @barrycarter (10m)
5. Guiding new posters seeking HW help @barrycarter (10m)
6. Homework policy replacement @DavidZ (10m)
7. Open discussion

Please keep the room clear of other topics during the chat session

So to start off, is anyone new here? Either new to the site or new to chat sessions?

ArtOfCode

@DavidZ waffles

David Z

Apr 5, 2016 16:04

:-P

Fancy seeing you here @ArtOfCode

ArtOfCode

Serial lurker. What can I say?

0celo7

@barrycarter I'm a double major

ArtOfCode

I think your 10 minutes estimate may have been a little over...

David Z

Not much, not while you remain a lurker

@ArtOfCode It's an upper bound

hi @Abobie

barrycarter

@0celo7 Not now.

ACuriousMind

Apr 5, 2016 16:05

@DavidZ User below 20 rep, can't reply.

David Z

Huh really? I thought people with <20 rep couldn't even get chat accounts.

Sorry, then.

ACuriousMind

They get these silhouettes instead of their actual profile pic as chat pic to mark they can't actually chat.

David Z

Ah, okay then. I had no idea.

ArtOfCode

Diamonds can grant write privileges if they feel like it, though.

0celo7

@barrycarter What?

David Z

Apr 5, 2016 16:08

Well, anyway, if we don't have any introductions to do, that's cool. The intent of this part of the agenda (which will be a fixture each time) is to help new members feel welcome and to catch any concerns they have about getting used to participating in the site.

barrycarter

@0celo7 Discuss later, not now.

David Z

@ArtOfCode ah, yeah... I forget how to do that :-/ I kind of wish we could remove the rep requirement for the chat session.

ArtOfCode

@DavidZ plz halp hao do i mek gd qstion

0celo7

What?

David Z

haha

ArtOfCode

Apr 5, 2016 16:09

@DavidZ room > control access

David Z

@ArtOfCode aks babby

But anyway, we should move on.

Oh right.

John Rennie

I don't think abobie has an account in the Physics SE ...

David Z

See, 10 minutes went by like nothing :-P

ArtOfCode

nope, only SO

John Rennie

Recent physics developments then?

David Z

Apr 5, 2016 16:11

Yeah. I put recent physics developments on the agenda to try to encourage us to exchange some actual physics news.

barrycarter

Newtonian mechanics apparently don't work well above certain speeds.

David Z

I didn't have anything particular in mind, but are there any recent events in the physics world anyone found interesting?

ACuriousMind

I haven't heard about any recent events :/

ArtOfCode

bbc.co.uk/news/science-environment-35938886

David Z

The LHC just started up for 2016

barrycarter

Apr 5, 2016 16:12

LHC?

ArtOfCode

Tangentially related, but sort of

barrycarter

oh, large hadron collider, never mind

ACuriousMind

@ArtOfCode lol

David Z

@ArtOfCode wow

John Rennie

Wouldn't we need to know where the aliens were to know when to turn on the laser?

ArtOfCode

Apr 5, 2016 16:13

How to make people not notice you: shine all of the bright lasers in their eyes

@JohnRennie You probably just saturate

John Rennie

And wouldn't we need a laser with the same spectrum as the Sun?

0celo7

Turn on lasers all the time in all directions.

David Z

So, make a star.

John Rennie

@0celo7 bloody engineering solutions

0celo7

@DavidZ Brilliant.

barrycarter

Apr 5, 2016 16:13

But that would mean aliens in difference directions would see us brighter... like a double star.

ArtOfCode

@0celo7 shine lasers at the sun, what happens then

0celo7

@ArtOfCode Supernova?

ArtOfCode

probably not enough energy

0celo7

Get more lasers.

barrycarter

We could just randomly blow up planets in our own solar system to show how tough we are.

John Rennie

Apr 5, 2016 16:14

@0celo7 let's try it and see. If it goes wrong we can restore from the last saved game.

ACuriousMind

@JohnRennie That's how you have so much rep! You just wait to see which questions become popular and then reload and answer them!

0celo7

@JohnRennie I have my finger perpetually on F9.

Just in case the sun blows up.

David Z

(hm, I'm thinking 5 minutes is not enough for this slot)

barrycarter

@0celo7 What does F9 do?

ACuriousMind

@DavidZ for the times where we have actual physics to discuss, probably not

David Z

Apr 5, 2016 16:16

@ACuriousMind yeah, definitely not. But this time we barely had anything, and there go our 5 minutes.

barrycarter

@0celo7 Also, saying you're an engineer/mathematician is like saying you're a brain surgeon who works a side job digging latrines.

ArtOfCode

ugh don't

John Rennie

Perhaps we should move on to the chat bot?

David Z

Yeah, good idea.

ACuriousMind

What's up with the chat bot?

David Z

Apr 5, 2016 16:17

@MAFIA36790 you around?

ArtOfCode

gonna go with no

barrycarter

@DavidZ I can't add agenda items during the meeting itself, right?

David Z

@barrycarter they can get tacked on at the end

John Rennie

5

Q: Do we want chat notifications of potentially low-quality posts?

There is a chat bot called Smoke Detector, active on several other SE sites, that automatically checks for potentially low-quality posts and writes chat messages to notify people about them. These messages can be posted to a dedicated chat room, as for Mathematics SE, or to the main site chat, as...

That chat bot?

0celo7

Why were both messages deleted?

barrycarter

Apr 5, 2016 16:18

@DavidZ Move or mirror this chat to something Pidgin can access so we don't need a bloody separate window for it.

John Rennie

He says, determinedly trying to keep on topic

user116211

@DavidZ: ??

David Z

Anyway, basically, @MAFIA36790 suggested that it might be useful to have a chat bot for this room to do... stuff. I'm not sure exactly what you had in mind though.

Maybe you can explain how it works in the chem room?

ArtOfCode

oh chemobot?

David Z

yeah, just as an example

ACuriousMind

Apr 5, 2016 16:20

What does it do, cook the chemicals I tell it to cook?

David Z

I don't actually know all that the bot they have can do, but the possibilities are quite broad

Looking up references, for instance

ArtOfCode

or if you're up for it, make your own

David Z

I think in chem they can post something like !!doi:[number] and it posts a link

ArtOfCode

I'm on the dev team of a framework for chatbots on SE

ACuriousMind

Can it onebox arxiv links?

David Z

Apr 5, 2016 16:21

I've been tinkering with the technology, but it would be great to use a framework if we can. No need to bug everybody about that, though; what I wanted to collect here is ideas.

@ACuriousMind no, a chat bot can't do custom oneboxing (but there is a script for that)

A bot can only read messages that are posted in the room and post replies

or it can post just plain messages, not replies

ACuriousMind

Hmmm

barrycarter

In theory, a chat bot could link this room to the outside world?

David Z

What do you mean?

user116211

in The Periodic Table, Mar 24 at 18:44, by Hippalectryon

Hi! I'm the (for now) unofficial bot of ChemistrySE's main chatroom. Here are the useful commands I provide : (don't add the brackets)
* img[molecule's name] -> I will try and upload an image corresponding to your molecule. You can give its name, formula, SMILES, or any common identifier.
* changelog -> shows the changelog
* help -> displays this message
~ Syntax : !!commandName/[arguments] ~
I also greet new users, and have a few more less useful commands for fun. If you find me annoying, you can ignore me by clicking on my profile image and chosing "ignore this user".

barrycarter

Like take messages posted here and post them somewhere else? and take messages elsewhere and post them here..... or I can save this until the last agenda item where I ask the same thing

David Z

Apr 5, 2016 16:23

@MAFIA36790 ah yes, thanks

@barrycarter It could, sure. It can do basically anything a normal chat user can do. The bot would run using a normal SE chat account - perhaps a person's account, or a dedicated account

ACuriousMind

Hmm...the molecule thing is cool, but we don't need that here

barrycarter

@DavidZ I was trying to sneak in my idea of connecting this chat room to Pidgin-compatible something via the bot topic.

user116211

Also:

user116211

in The Periodic Table, Mar 27 at 8:55, by Hippalectryon

David Z

@barrycarter you're far from the first to think of that - I'm sure there are questions about it on Meta Stack Exchange, but the team is not in favor

barrycarter

Apr 5, 2016 16:24

I could use a steaming hot cup of an image of coffee right about now.

David Z

that does sound kind of nice

Anyway, we're already a few minutes behind schedule - not a big deal, but probably time to move on. This is something to think about for the future.

barrycarter

@DavidZ Yes, I think I've had the battle elsewhere... but, could we create one just for Physics without riling meta.se?

I've threatened to create one myself, but I'm too lazy.

David Z

@barrycarter no, and ask me later why not

So what's the next topic?

John Rennie

4. Canonical relativity answers @barrycarter (10m)

barrycarter

OK, here goes:

There are a LOT of questions about special relativity on this site, people being confused by Lorentz contractions, time dilation, simultaneity, etc, and there doesn't seem to be a good canonical answer. Someone named @JohnRennie should write one.

ACuriousMind

Apr 5, 2016 16:27

Hasn't John already tried that? With quite a lot of success?

John Rennie

40

Q: What is time dilation really?

Please will someone explain what time dilation really is and how it occurs. There are lots of questions and answers going into how to calculate time dilation, but none that give an intuitive feel for how it happens.

relativity time-dilation

barrycarter

Has he? I still see lots of unanswered questions, or questions with multiple unaccepted answers, or... hmmm. OK,

@JohnRennie But how about Lorentz contraction and the Lorentz transformation and simultaneity?

ACuriousMind

Also relevant:

13

Q: Do we want and need a set of canonical questions with canonical answers?

This is a proposal that has been discussed to some extent in the h bar chat (especially with @ACuriousMind and @alemi), and a meta post to gauge the response of the rest of the community is long overdue, so here we go: All long-time SE users are aware that there are always a number of questions ...

discussion questions site-faq duplicates

John Rennie

As for Lorentz contraction, it should be banned from all mention. It's not a contraction it's the rotation of a four vector.

barrycarter

@JohnRennie I think the problem is not time dilation, etc, but the problem of combining these with each other.

John Rennie

Apr 5, 2016 16:29

To be honest it's hard to see how such an canonical question could usefully be written without ending up as textbook length

barrycarter

The canonical answer to: how do Lorentz contraction (which maybe doesn't exist but people believe in it, so you have to deal with it), time dilation, and simultaneity all interact with each other?

ACuriousMind

They...don't "interact". Those are just different manifestations of changing frames.

John Rennie

@barrycarter I would struggle to write an even remotely concise answer to that

barrycarter

OK, I think the problem run into isn't using contraction/dilation, but when they start combining them with each other.

ACuriousMind

I think we want canonical answers, but not to such broad questions

barrycarter

Apr 5, 2016 16:30

@ACuriousMind Yes, but many people try to treat them individually.

John Rennie

The solution is to understand that relativity is a geometric theory

David Z

An answer needs a question, of course. So it might be useful to start by thinking, what question would need to be answered?

barrycarter

OK, but the questions I see are of the form "but when we combine the LC and time dilation, the waves from Earth are 3 times as fast as themselves"

John Rennie

Once you have grasped this the rest comes naturally

barrycarter

@JohnRennie Yes, but I'm talking about newbies here.

John Rennie

Apr 5, 2016 16:32

They need to be told that relativity is a geometric theory

barrycarter

@JohnRennie I prefer the matrix transformation myself, but that's not going to stop people asking questions about LC and dilation.

John Rennie

@barrycarter you need to be told that relativity is a geometric theory!

barrycarter

So that's it? "relativity is a geometric theory, so your question doesn't make sense"?

David Z

@barrycarter do you have specific examples you can link to?

John Rennie

... and here's how to reformulate it to make sense ...

barrycarter

Apr 5, 2016 16:33

Let me find the one that started the huge "fight" between WillO and me... two secs

ACuriousMind

We can't clean up every specific confusion that people have because they read the horribly confused and outdated presentations from school textbooks, just like we don't clean up every confusion in questions that assume the big bang happened at a point. We close those questions as duplicates of "Did the Big Bang happen at a point" and move on.

John Rennie

It feels a bit as if we're edging into:

barrycarter

This will take some time. It was basically someone coming up with a relativity "paradox" by showing two times must be less than each other.

John Rennie

5. Guiding new posters seeking HW help @barrycarter (10m)

Bill N

I think it would be admirable if we DID try to clean up some of the confusion by having a description of why the rotation/matrix approach is better.

barrycarter

Apr 5, 2016 16:35

0

Q: Question/Doubt about Time Dilation Symmetry in Special Relativity

Apologies if this has been asked and answered before, as I am still having doubts reconciling the symmetrical effects of time dilation (i.e each frame sees clocks of other frame slowing down), and I am not sure where I am making a conceptual mistake. Assume that we have Earth and a distant plane...

special-relativity time-dilation

David Z

@barrycarter if you don't mind a quick edit:

barrycarter

I don't think we're ever going to get away from the fact people are taught relativity as LC and dilation.

David Z

I think oneboxing helps

barrycarter

@DavidZ That's what I wanted to do, but how do I do that?

David Z

Post only the URL. Nothing else.

barrycarter

Apr 5, 2016 16:36

Oh!

Bill N

Take a look at John Denker's work at av8n.com/physics/spacetime-welcome.htm

John Rennie

I'll have to take that offline to go through it. There's too much there for me to skim in the time frame of this chat.

David Z

Anyway, @JohnRennie is right, we do kind of need to be moving on.

barrycarter

OK...

David Z

We don't have enough time here to do more than touch on things.

So you also had some ideas about FAQs and guiding people seeking HW help?

barrycarter

Apr 5, 2016 16:37

Yes... I think we see a lot of basic at^2/t + vt + s0 questions here

John Rennie

@barrycarter which we close

barrycarter

Basic high school physics over and over again. IE, if the pressure of an ideal gas doubles and the temperature stays the same...

Yes, I'm saying we should have a prominent FAQ.

Bill N

When I see things like that, I'm wondering why they aren't going to see their teacher to get help.

barrycarter

@BillN That's sort of a good question, but people often complain that their teachers suck.

Or they don't speak English well or whatever.

ACuriousMind

@BillN I think they don't consider their teachers approachable

John Rennie

Apr 5, 2016 16:38

People won't read FAQs, instructions or whatever. It costs nothing to post, and they may get an answer, so they post.

David Z

@barrycarter My question is, where would you put the FAQ on the site to make it more prominent?

ACuriousMind

Whether because they're incompetent, or unfriendly, or whatever

barrycarter

I realize that you can get to a FAQ of sorts by looking for most duplicated answers, but let's make that link a lot easier to find.

David Z

I also agree with what @JohnRennie said, but for argument's sake... how to make it easy to find?

Bill N

Yeah, I experience that, too, but the ones who visit once come back regularly.

barrycarter

Apr 5, 2016 16:39

@JohnRennie OK, but at least we can say "read the FAQ".

ACuriousMind

Also, many of them don't actually want to learn anything. They just want the answer to get a passing grade.

barrycarter

@ACuriousMind I'd like to have a "please read the FAQ first and see if that doesn't answer your question" thing.

[back in 2m, sorry]

John Rennie

Wow, as if by magic we're moving seamlessly on to:

6. Homework policy replacement @DavidZ (10m)

Bill N

@ACuriousMind That happens, and we probably get mixed reactions when we brush them off.

David Z

@JohnRennie Ah, yeah... we ran a bit overtime with some of the earlier sections though so I think we can hold off on that for just a few more minutes

ACuriousMind

Apr 5, 2016 16:41

One problem is that the tour, which is supposed to be the starting point for new users, doesn't actually mention that questions may be about "physics" and still be off-topic.

John Rennie

@DavidZ I didn't mean we need to move on now, I meant we've started talking about homework

barrycarter

[back]

David Z

@JohnRennie fair ;-)

barrycarter

@ACuriousMind Plus no one reads it.

I suggest we take for granted that people will post questions without reading anything first.

ACuriousMind

@barrycarter Well, if they can't be bothered to read the thing you are explicitly pointed to after registering, that's not our fault.

barrycarter

Apr 5, 2016 16:42

The question is: what do we do after they've done that?

ACuriousMind

@barrycarter I disagree. I'm not going to accomodate laziness.

John Rennie

Could we require new users to go to the tour page before their first post

barrycarter

@ACuriousMind No, nothing's "our fault", but reality is reality.

We're not here to discipline users :)

John Rennie

They won't read it, but it might make them think twice ..

ACuriousMind

@JohnRennie Oh, like the EULAs you read everytime before installing something? ;)

barrycarter

Apr 5, 2016 16:43

I think trying to change luser behavior is difficult. If we really want to be helpful, we have to deal with that.

John Rennie

Math Overflow has a pop up that appears when you start typing an answer. Can we do something like that?

David Z

@barrycarter FWIW, we do that to some extent. At least when I'm interacting with new posters, I don't expect them to have read much of our policies; I treat them as things to be linked to and read on demand, rather than prerequisites to participating.

But it would be nice to get more people to read and understand at least a little bit.

barrycarter

@DavidZ Right. Now, can we say "we've created this here FAQ thing to answer basic physics questions.. read it, come back if it doesn't help". That's what I think will be most effective.

David Z

@JohnRennie do we not have that? We could ask about it

barrycarter

That's what many sites do. "we won't answer questions that are already answered in the FAQ"

People will just click it away.

David Z

Apr 5, 2016 16:45

@barrycarter I think that's the intent of closing as duplicate.

ACuriousMind

I bet many read the tour - but the information about "off-topic questions" is buried in the help center, which is declared to be about "in-depth information" in the tour. No one is going to assume to need in-depth knowledge to ask their first question.

barrycarter

@DavidZ OK, but I think the link you lead them to isn't really super helpful: it's more about policy than actual answers.

In the 80s, I cost the Internet hundreds, if not thousands, of dollars by posting news messages :)

David Z

@barrycarter for closing as duplicate? The link we lead them to is the question that answers what they wanted to ask.

Anyway, this is definitely something worth discussing further but now I think we might want to move on to the homework policy replacement. If that's okay?

barrycarter

@DavidZ Oh... ok, I thought they got led to the "we do not answer homework questions" link, at least that's what I've seen.

I'm good with that.

ACuriousMind

@barrycarter There's a difference between closing as HW and closing as duplicate.

barrycarter

Apr 5, 2016 16:47

@ACuriousMind Yes, I'm talking about HW, so we're right on topic :)

David Z

@barrycarter ah, no, that's different. That's... well, that's going to be changing soon anyway.

user116211

@barrycarter: You are deviating from the topic....

David Z

So, yes. Speaking of the homework policy, and getting rid of it finally: I know people are sick of this, but we have some work to do before we can change it over to a new policy.

I made a post on meta about this a few hours ago.

3

Q: Replacing the homework policy 1: what existing questions should be on/off topic?

TL;DR: post examples of current questions which are edge cases for the new policy, look through the list, and vote answers up if you think they should be on topic or down if you think they should be off topic. When we last left the ongoing examination of our homework policy, the community ha...

discussion featured scope homework insufficient-effort

Slereah

Hey

David Z

This is my proposal for a concrete plan to make the new policy and change it over.

user116211

Apr 5, 2016 16:48

@Slereah late....

David Z

howdy @Slereah

Slereah

Well I was going home

user116211

@Slereah oh. Well, the right time....Reformation of HW policy is in the table...

ACuriousMind

I mean... I guess it can't hurt to revise things with everything we've learned since the last time, but man I'm worn out on talking about homework. Maybe to put an optimistic spin on things, it's good that things are all running well enough elsewhere that this is all there is to discuss? — tpg2114 49 mins ago

Well...can't say he's wrong :P

David Z

Hey, I'm trying to make it easy on y'all with this meta post ;-)

barrycarter

Apr 5, 2016 16:50

I'd say close with a link to reference sites.

David Z

Any comments would be welcome, of course, but what I'm really looking for is to get a broad survey of how people would like to see existing questions handled - in terms of whether they should be on topic or off topic.

user116211

@barrycarter like?

barrycarter

@MAFIA36790 wolframalpha.com for computations

Slereah

I don't really care about the HW policy?

John Rennie

I generally go through the review queues first thing in the morning, so yes I can start picking out representative homework questions and post them as answers to your Meta post.

barrycarter

Apr 5, 2016 16:51

Or even the long post we have about homework help sites.

David Z

@JohnRennie yes, that would be fantastic.

user116211

@Slereah hmmm... don't you want the betterment of PSE?

David Z

I'm trying to focus on the edge cases - not the obviously off-topic ones, nor the obviously good and on-topic ones

barrycarter

So the goal is to find edge cases?

Slereah

Oh I have plenty of ideas for the betterment of PSE

David Z

Apr 5, 2016 16:51

Yeah, more or less.

Slereah

Can't discuss them or I'd get banned, tho

2

user116211

@Slereah :P

David Z

Basically, once we get a bunch of links, and a bunch of votes on those links to show what people consider on-topic or off-topic, I'll go through the examples and use them to help formulate a draft policy.

ACuriousMind

Edge cases with respect to the current policy or edge cases with respect to our own judgement?

John Rennie

With respect to our own judgement

David Z

Apr 5, 2016 16:52

Edge cases with respect to your judgement - or, what you think the new policy should be.

The questions' status with respect to the current policy doesn't really matter.

Slereah

So anyway

No more GR for now

It's gonna be ALL QFT ALL THE TIME

ACuriousMind

@barrycarter We have this meta post.

Slereah

Can't get a thesis with GR m8

David Z

@Slereah we're trying this new thing where we actually stay on topic during the chat sessions

Slereah

Gotta do the fancy QFT

Oh well

barrycarter

Apr 5, 2016 16:53

@ACuriousMind Yes, that's the one I meant.

Slereah

I'll go watch my soaps in the meanwhile

David Z

Anyway, the most useful links to collect will be those that really help pin down the nature of the new policy.

Not the obvious ones.

If everybody contributes a couple links and a few votes, we should have a pretty good sample.

and it won't be much work for anyone

Slereah

(and do the cardio!)

John Rennie

It will be interesting to see what others consider borderline.

Judging from the review queues I seem to be towards the lenient end of the scale (perhaps surprisingly)

David Z

I would hope there's not too much of a spread, but yes, this will be good to see.

So that's ~10 minutes on the replacement homework policy. Time for open discussion? This is meant to revisit any topics that people wanted to say more on but didn't have time, or to bring up anything new that could use the community's attention

barrycarter

Apr 5, 2016 16:58

I think that a lot of the policy discussion here is about how we can reform newbies and HW question askers to become better people. That's a lot harder than just accepting there will always be newbies, and we should try our best to give them some level of help, though not to the point we're actually answering questions for them.

Slereah

I have no issue to raise that I don't already know will not change :p

David Z

I would also welcome thoughts on the idea of having an agenda in the first place. Obviously the timings need some work, but overall do we think it's useful?

barrycarter

@DavidZ Why do we have these chats at all? Not that many more people show up?

John Rennie

It's good to have some focus, otherwise we just chat as usual

David Z

@barrycarter indeed there will always be newbies; I think we know that. But that doesn't necessarily mean we should try our best to give them some level of help.

ACuriousMind

Apr 5, 2016 16:59

@DavidZ I like it, it makes the session feel more session-y

David Z

@barrycarter Normally the disparity is more prominent - that is, there are a lot more people in the chat session than at other random times.

barrycarter

@DavidZ OK, that's where I think we disagree. There was some guy complaining about rudeness in meta.

David Z

@barrycarter Yeah, perhaps so. The thing is, people have many different ideas of rudeness.

2 days ago, by David Z

I suspect the poster of that question thinks of good treatment as getting their questions answered.

^^ for example

There is a lot more to be discussed on these topics, but unfortunately we're out of time.

John Rennie

@barrycarter it's not cool to be rude, but I don't think anyone hereabouts is deliberately rude.

FenderLesPaul

@Danu Bousso is so awesome!

I loved talking to him

I think he sold me; Berkeley it is

:)

John Rennie

Apr 5, 2016 17:01

Though sometimes they can be short - very short! :-)

David Z

Good chat session everybody. See you at the next one in two weeks!

The h Bar

Participants