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JMac

00:00

Little does he know, as soon as I read that, I started finishing my theory of hyper-negative metaquantum space-time-temperature and how that causes relative de-expansion of the holograph of the universe

which will obviously supersede his theory, being far more accurate than his

Ryan Unger

maybe you'll get a prize for that

JMac

I better, it's definitely correct because it makes sense in my head

danielunderwood

I wonder if the people who post things like that ever take a step back and learn things properly

knzhou

00:15

It's just a shame -- such a small fraction of people actually care about learning physics that the cranks outnumber them.

To learn physics deeply you need a lot of things, but to be a crank you just need a few bad personality traits.

JMac

I don't think the cranks are really that prevalent. They're just a vocal minority.

vzn

01:07

in theory salon, 24 secs ago, by vzn

The AI that can make Mona Lisa smile: Samsung reveals algorithm that creates fake talking-head videos using just ONE photo / dailymail

lol whats with all the attitude about coding? ok, ok, zuckerberg severely tarnished, but cmon coding geeks are still super cool and this cachet can only climb higher. why software is eating the world/ andreessen (2011) wsj.com/articles/SB10001424053111903480904576512250915629460

... as for physics cranks, someone talking about warped spacetime at the dawn of the 20th century would have been considered a certifiable one. but something like that could never happen again, right? because science + physics has all the answers now lol!

7 hours later…

Slereah

07:53

morgen

Slereah

08:09

Jost's brief topology reminder is quite nice

Emilio Pisanty

@JMac ah, that delete button is so tempting

But it's probably better if this gets scooped up by the roomba in nine days' time

3 hours later…

user8718165

11:18

I have a doubt on a question on the site.....if anybody could help please physics.stackexchange.com/q/375614/208199

Danu

@ACuriousMind bahahaha! @EmilioPisanty Congrats, and have fun ;D

user8718165

Why doesn't the water move out of the bottle in the 1st setup even when there is pressure difference...is it only because of atmospheric pressure?

Emilio Pisanty

@user8718165 yes.

@Danu will do =)

user8718165

@EmilioPisanty oh thanks...is the net opposing force= force due to air inside the bottle+force from external atm.?

Emilio Pisanty

11:34

@user8718165 not quite. The force from the air pressure inside the bottle acts in the direction of pushing the water out

it counteracts a part of the force from the external atmosphere

which is why the pressure inside ends up being lower than atmospheric

so the net opposing force is really the force from the external atmosphere minus the force due to air inside the bottle

user8718165

@EmilioPisanty aha...I think I get it...so does just a little water flow out of bottle to make inner air pressure less than atm pressure?

Emilio Pisanty

exactly

(unless the bottle was completely full, in which case either the water doesn't drop, or it drops to form a vacuum above it.)

user8718165

@EmilioPisanty I think the card on inverted tumbler magic works the same way

Emilio Pisanty

@user8718165 yes.

user8718165

@EmilioPisanty oh thanks got it...so in order to have all the water out we need to have a sufficiently long neck or a very long pipe? is it(as is in the 2nd case)

Emilio Pisanty

11:41

@user8718165 or, more frequently, flow of air in through the opening at the bottom

which is suppressed by the surrounding water in the configuration you linked to

user8718165

@EmilioPisanty air from atm...into pipe...into upper part of the bottle? then the pressure inside the empty part of the bottle will be equal to atm pressure.The only force pushing the water out then will be hydro-static force...??

@EmilioPisanty Well...thanks you helped

5 hours later…

Emilio Pisanty

16:35

\today is not \today

@ZeroTheHero I just raised the arXiv timings thing as a GitHub issue, see above :-).

bolbteppa

Turns out theoretical physics is really hard :(

Kyle Kanos

16:57

@bolbteppa just use a computer

ZeroTheHero

17:23

@EmilioPisanty Thanks for the heads up. Sorry for being brief but leaving tomorrow on yet another idiodyssey (how do I get pulled into such schemes). (wave)

Emilio Pisanty

17:35

@ZeroTheHero ::wave::

(also ::particle::)

I'm not sure whether there's anything to do here - but it may help if you subscribe to the issue on GitHub (if you have an account). If nothing else, you'll find out if they fix it.