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[TheBiggerFish]

no don't say that people might actually believe it

Er, isn't that how that happens, though?

[Rolan7]

But there's some other phenomenon which is sorta like temperature and it's being called temperature and it can go negative.

What you'll quickly learn is that all cases such as this were you being lied to as to the definition in the first place. The temperature that can go negative is the same temperature as what you use normally.

Like how momentum is mv, but really it's actually E/c, but that's harder to calculate for massive bodies (while being exactly equal for massive bodies) so you weren't taught that and now people freak right out over being told that light has momentum despite being massless god DAMMIT

I thought you were a descriptivist, though I may be mistaken.
If "temperature" in everyday life is whether we feel hot or cold...
And "temperature" in physics is activity of the atoms, with a clear bottom at 0 Kelvin for "inactive, but practically impossible"...

Where the hell is the lie?  Because some physicists found a weird interaction near absolute zero and decided to describe it as "negative temperature"?  That's on them!  That's literally redefining the word "temperature" in a way that makes no sense to anyone but them!

And I'm not sorry that it's fucking weird that a thing with no mass can have momentum.

[Putnam]

I'm a descriptivist, yeah, but scientific terms are specifically invented by individuals to mean something, so it's sort of important that they have a well-defined, non-colloquial meaning. The colloquial meaning of temperature is a strict subset of the meaning that allows for negative temperature, and the definition of temperature you'll see in articles about negative temperature is the same one used for positive temperature. The lie is on the same level as "you can't subtract 5 from 4".

And I'm not sorry that it's fucking weird that a thing with no mass can have momentum.

I am, because it means you weren't taught well somewhere along the line.

[milo christiansen]

While playing a game late at night (as is my habit) it suddenly minimizes and a console window displays for a split second. Yesterday I finally figured out why. Apparently MySQL runs a command line app as part of its attempt to check for updates, and on Windows this generates a console window unless you make a special effort to hide it.

Hey, who uses their development computer late at night? No one will notice...

[Frumple]

Awww, shit mil. You just said it in a public place. No one notices because everyone that mentions it gets their knees broken by the ninjas microsoft's PR keeps on retainer. I hope you've got good insurance

[i2amroy]

Also have a look at the article i edited in, it's pretty fascinating, since they also mention going very slightly below absolute zero, which causes a number of odd effects (including, apparently, replicating the effects of dark energy). But, the zero itself still hasn't been reached, they just merrily skipped past it by abusing quantum mechanics. Or uh, something like that, i can't claim to actually understand it. :v

This is a case where the authors of the article don't really perfectly understand what's going on either and are getting slightly confused, (much as you are). As noted by Rolan7, this comes from eh fact that we use the term "temperature" in two different ways, as "kelvin temperature" and as "thermodynamic temperature". Kelvin temperature is the one that absolute zero happens in, and is related to the total amount of kinetic energy in the atoms present. Thermodynamic temperature, on the other hand, doesn't measure kinetic energy in the atoms, but rather measures how much energy wants to flow towards or away from a given sample. The original experiment mentioned is talking about thermodynamic temperature, i.e. they have managed to make a weird thing happen where they got energy to flow from a colder (kelvin temperature) object to a hotter (kelvin temperature) one (i.e., giving it a negative thermodynamic temperature). The author of the nature article, (like many other authors did when that particular experiment first hit the net), is falsely conflating the negative thermodynamic temperature (which just means energy is flowing from a colder place (kelvin temperature) to a hotter one (kelvin temperature) with a negative kelvin temperature (which is impossible, as it would mean that you had negative kinetic energy in the atoms).

Don't worry about the confusion, as I mentioned, if you search back around the time that that article was posted you'll find plenty of other people (some of them fairly respected science journalists) getting confused about the fact that the terms are the same.

[Rolan7]

I'm a descriptivist, yeah, but scientific terms are specifically invented by individuals to mean something, so it's sort of important that they have a well-defined, non-colloquial meaning. The colloquial meaning of temperature is a strict subset of the meaning that allows for negative temperature, and the definition of temperature you'll see in articles about negative temperature is the same one used for positive temperature. The lie is on the same level as "you can't subtract 5 from 4".

And I'm not sorry that it's fucking weird that a thing with no mass can have momentum.

I am, because it means you weren't taught well somewhere along the line.

Most discussions of "negative temperature" I'm finding begin by pointing out that it relies on a controversial or different definition of temperature.  If I say that temperature is a measure of the activity of atoms, I'm not wrong.  This negative temperature idea uses a different, potentially interesting, model.  I wish it'd use a new term, but it doesn't make me wrong.

The colloquial is "ow I burned my hand" or "jeeze it's chilly" which is why I pointed it out.  "Kinetic energy in atoms" isn't colloquial, it's very scientific.

As for mass:

In physics, mass is a property of a physical body. It is the measure of an object's resistance to acceleration (a change in its state of motion) when a force is applied. It also determines the strength of its mutual gravitational attraction to other bodies.

So if I'm so wrong, go edit Wikipedia instead of giving me a hard time.  Except you can't, because that's the tried and true definition of the word and the one everyone understands!  Even physicists with deeper understanding of what's actually going on understand that "mass" is resistance to acceleration, at least outside their specific field of study.  If they want to define "mass" as something else, good for them, I hope it advances science.  Doesn't change the definition of the word.

Photons are *weird*, okay??  They don't obey the same rules as matter.  That doesn't mean I wasn't taught well in high school, thank you.

[Putnam]

That definition of mass is correct and I never said anything that implied otherwise. I'm saying the definition of momentum as mass*velocity is wrong (it's a convenient way to calculate it for massive objects, not the definition).

Photons are *weird*, okay??  They don't obey the same rules as matter.  That doesn't mean I wasn't taught well in high school, thank you.

No, see, this is the problem, putting different things into different boxes and saying they play by different rules implies a compartmentalized universe, which is a bizarre way of looking at things.

[Rolan7]

Fair enough, thanks for explaining it some.

[hector13]

We haven't reached absolute zero because absolute zero cannot be reached. It's an asymptote, a singularity, like the speed of light.

Yeah.  If you reach negative Kelvin you overflowed the universe's temperature datatype and wrapped around.

Like nuclear Gandhi.

[pisskop]

I seem to remember some media player or another being able to save youtube/other videos that were streamed for later viewing.  is this true?

[Frumple]

Quick google does make it look like there's at least a couple that can capture streaming video. Don't ask me which one's worth a damn, though. Never used one, heh.

[pisskop]

:p

Jerkhole, I was hoping somebody would handhold me through it.

I got it to work on good ol' vlc.  Just needed 10 or so minutes of fiddilin'.  thanks

[Frumple]

Sudden terrifying urge to figure out a way to make a forum where you can only communicate through smilies/emoticons/etc. All text disabled, no formal languages allowed. The Great Emoji Pantomime Orgy from Hell. Abandon hope, all ye. Not just those that enter. Everyone.

[pisskop]

I believe theyre calling the movie 'Emojii'

Please kill me

We're gonna have to make it a suicide pact, you and I.
Who the hell is even this Leondis person and why does he think it's a good idea?

He seems to have written a few unnecessary sequels to Disney movies and a couple of mediocre original animated films. The best-rated film he's worked on was Prince of Egypt, for which he had the crucial, project-making role of story artist.

Barely comprehensible press release (warning: press release may cause blindness and vomiting)