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# Quantum Gas Goes Below Absolute Zero

#### samzenpus posted about a year and a half ago | from the stop-moving dept.

264

First time accepted submitter mromanuk writes in with a story about scientists at Ludwig Maximilian University of Munich who have created an atomic gas that goes below absolute zero. "It may sound less likely than hell freezing over, but physicists have created an atomic gas with a sub-absolute-zero temperature for the first time. Their technique opens the door to generating negative-Kelvin materials and new quantum devices, and it could even help to solve a cosmological mystery."

cancel ×

### Re:Not as new as it seems (1)

#### Intrepid imaginaut (1970940) | about a year and a half ago | (#42473573)

So we can make stuff out of lasers now? I would like to place an order for my lightsabre, please!

### Re:Not as new as it seems (5, Funny)

#### 140Mandak262Jamuna (970587) | about a year and a half ago | (#42473677)

Epic fail. Every Jedi knight builds his own light sabre. What the galaxy is coming to now a days, aspiring jedi knights nonchalantly ordering their light sabre by mail order... What next? Subject verb object order Yoda learns?

### Re:Not as new as it seems (3, Informative)

#### devent (1627873) | about a year and a half ago | (#42473691)

Next is a pre-school class with Yoda with a bunch of 5 years kids. Also the kids get the light sabres from the dead Jedi, it's all in the brochure: So You Want Your Kid To Be A Jedi. Oh yeah, your kid need to take drugs if they get to puberty, because love is forbidden and leads to the dark side.

### Re:Not as new as it seems (1)

#### Impy the Impiuos Imp (442658) | about a year and a half ago | (#42474147)

Not one of those clowns looked competent to build his own saber, including Darth Vader, who also wasn't competent with engines or cobbling together a droid from junk parts.

### Re:Not as new as it seems (2)

#### Joce640k (829181) | about a year and a half ago | (#42474317)

Darth Vader doesn't worry about his honor, he orders them by the dozen from Farnell.

### Re:Not as new as it seems (1)

#### Anonymous Coward | about a year and a half ago | (#42474479)

A series produced protocol droid from junk parts. And no, that is not the only thing that bothered me with those movies.

### Re:Not as new as it seems (1)

#### whoisjoe (465549) | about a year and a half ago | (#42474377)

What the hell want you from 900 year old man? English perfect?

(From Mad Magazine's spoof of Return of the Jedi)

### Re:Not as new as it seems (4, Funny)

#### Noughmad (1044096) | about a year and a half ago | (#42474407)

What the hell want you from 900 year old man? English perfect?

The Doctor seems to be doing quite well for his age.

### Re:Not as new as it seems (2)

#### GameboyRMH (1153867) | about a year and a half ago | (#42473947)

I want a laser wallet to store laser beam currency! (That's what they use in the future.)

That'd be the coolest wallet ever!

RvB is the best

### Re:Not as new as it seems (0)

#### Anonymous Coward | about a year and a half ago | (#42474067)

More prior art: Costello et al [youtube.com] anticipated these developments in the '70s.

### better explanation (5, Informative)

#### ssam (2723487) | about a year and a half ago | (#42473469)

wikipedia has quite a good explanation of negative temperature.
http://en.wikipedia.org/wiki/Negative_temperature [wikipedia.org]

### Re:better explanation (5, Interesting)

#### hydrofix (1253498) | about a year and a half ago | (#42473527)

An interesting quotation from that article:

A substance with a negative temperature is not colder than absolute zero, but rather it is hotter than infinite temperature.

It seems this is a very specific quantum mechanical perversion, and no classical systems can reach the state quantum physicists call "negative temperature".

### Re:better explanation (0, Troll)

#### BitZtream (692029) | about a year and a half ago | (#42473547)

It seems to me to be a retarded description, like calling infinity + 1 a negative number.

They need to use a proper name for it, not something that only makes sense if your the kind of person that likes to say things in such a way that no one else understands what you mean just so you can claim its technically correct with a smug attitude.

### Re:better explanation (3, Informative)

#### Anonymous Coward | about a year and a half ago | (#42473615)

Sure, don't bother trying to learn why this is; just blame it on someone else and think yourself the better man for being ignorant.

### Re:better explanation (2)

#### Zontar The Mindless (9002) | about a year and a half ago | (#42473621)

Next on Slashdot... AC informs us that water is wet... Right after these important messages...

### Re:better explanation (3, Funny)

#### JMJimmy (2036122) | about a year and a half ago | (#42473693)

Water is not wet, it just feels that way ;)

### Re:better explanation (0)

#### Zontar The Mindless (9002) | about a year and a half ago | (#42473749)

Next time I grow a hair, you're welcome to split it.

### Re:better explanation (1)

#### JMJimmy (2036122) | about a year and a half ago | (#42473891)

wow... someone can't take a joke. Note the smiley face.

So is yours.

### Re:better explanation (0)

#### Anonymous Coward | about a year and a half ago | (#42473991)

> Water is not wet.
It certainly is. If you look at water molecules under a microscope you can definitely see moisture dropping off of them, like rain. So they're definitely slippery little devils. To see this, try picking a single water molecule up with your bare fingers. It's impossible!

### Re:better explanation (1)

#### Anonymous Coward | about a year and a half ago | (#42474019)

Water is not wet, it just feels that way ;)

Actually it's just drier than infinite dryness..or something...

### Re:better explanation (4, Insightful)

#### Anonymous Coward | about a year and a half ago | (#42474293)

Sure, don't bother trying to learn why this is; just blame it on someone else and think yourself the better man for being ignorant.

Richard Feynman [wikiquote.org] : "If you can't explain something to a first year student, then you haven't really understood it."

I'll take Feynman's attitude towards obtuse, confusing jargon over your smug shit any day.

### Re:better explanation (3, Interesting)

#### ElectricTurtle (1171201) | about a year and a half ago | (#42474397)

While I think he gave himself an out in the specification/qualification of 'first year student', there's a degree of hypocrisy in that vs. this [youtube.com] . (Specifically after the 4 minute mark where he basically says you can't properly explain certain things in physics through intuitive metaphors.)

### Re:better explanation (-1)

#### Anonymous Coward | about a year and a half ago | (#42473619)

> They need to use a proper name for it, not something that only makes sense if your the kind of person that likes to say things in such a way that no one else
> understands what you mean just so you can claim its technically correct with a smug attitude.

You know, that criticism would carry a lot more weight if you hadn't phrased it in a an overly-long run-on sentence that has to be read four times to be be understood.

### Re:better explanation (1)

#### Schmorgluck (1293264) | about a year and a half ago | (#42474015)

While the absence of punctuation is condemnable (and you're guilty of it too), that sentence doesn't qualify as a run-on, since it doesn't contain two independant clauses, but one main clause and a chain of subordinate clauses.<\pedantrysquared>.

### Re:better explanation (0, Troll)

#### Anonymous Coward | about a year and a half ago | (#42474611)

> the absence of punctuation is condemnable (and you're guilty of it too)

Would you believe I was aiming for ironic but, for the sake of readability, left it a bit too short to be effective?

While I'm here, I also forgot to mention the GP's hypocritically smug sense of "I dun need no fancy book lernin'" reverse snobbishness against anyone who seems to know more than he does in a given field which also is also probably a bit too long to go without a comma but isn't technically a run-on sentence until I add this bit here on the end of it.

### Re:better explanation (5, Informative)

#### Anonymous Coward | about a year and a half ago | (#42473637)

Temperature isn't defined in physics as anything to do with heat, but the derivative of energy with respect to entropy. Absolute zero is the temperature at which there is no energy left in the system. At normal temperatures, it is positive. At absolute zero, it's zero. If you can create a system with dU/dS as negative, it's technically negative temperature, even though the system still has energy.
It's hard to explain due to how things like temperature and energy are defined, not because physicists are being smug. There isn't a proper name for it because it doesn't happen very much. That's why it's news.

### Re:better explanation (0)

#### Anonymous Coward | about a year and a half ago | (#42474127)

Temperature isn't defined in physics as anything to do with heat, but the derivative of energy with respect to entropy.

Sure it is. From the 0th law of thermodynamics: If body A and B are in thermal equilibrium and B and C are in thermal equilibrium, then A and C are in thermal equilibrium. Thermal equilibrium means that no heat is transferred (Q=0) and two bodies that are in thermal equilibrium have the same temperature (T_A = T_B). Thus, if bodies are not in thermal equilibrium, they are transferring heat and have different temperatures. The direction of transfer from hot to cold is due to entropy and the 2nd law.

### Re:better explanation (1)

#### Anonymous Coward | about a year and a half ago | (#42474501)

(Not original AC parent...)

The laws of thermodynamics refer to entropy, energy and temperature, not necessarily to heat. There is no contraction to what the previous AC said and the laws of thermodynamics. By far, the most common application is to systems where the internal energy is stored as heat. But the laws and thermodynamics have been found to be way more general in modern statistical mechanics, and there are places it can be applied to where temperature has different direct meaning, but follows the same principles and laws. Some of those cases have negative temperatures in addition to positive temperatures, and it falls straight out of the same expressions naturally, as the previous AC was trying to get at, and not just some arbitrary label.

### Re:better explanation (0)

#### Anonymous Coward | about a year and a half ago | (#42474637)

I stopped reading when you started talking about storing heat. You don't store heat, you transfer it. Heat is a transfer of energy. It is not something that can be stored.

### Re:better explanation (2)

#### slashmydots (2189826) | about a year and a half ago | (#42474581)

So with zero energy, the atoms aren't moving at all. So what are the atoms doing at negative temperatures?

### Re:better explanation (5, Funny)

#### Rogerborg (306625) | about a year and a half ago | (#42473665)

"Technically correct" is the best kind of correct.

### Re:better explanation (5, Funny)

#### mrbester (200927) | about a year and a half ago | (#42473787)

It's the previously unquantifiable temperature of a McDonald's Apple Pie.

### Re:better explanation (1)

#### OolimPhon (1120895) | about a year and a half ago | (#42474025)

It's the previously unquantifiable temperature of a McDonald's Apple Pie.

For very small values of "Apple".

And "Pie".

### Re:better explanation (2, Informative)

#### Anonymous Coward | about a year and a half ago | (#42473819)

If by "retarded," you mean "correct," then yes, that explination is very "retarded." If you bothered reading the wikipedia article, it explains it pretty clearly:
"The paradox is resolved by understanding temperature through its more rigorous definition as the tradeoff between energy and entropy, with the reciprocal of the temperature, thermodynamic beta, as the more fundamental quantity."
"The inverse temperature = 1/kT (where k is Boltzmann's constant) scale runs continuously from low energy to high as +, . . . , ."

### Re:better explanation (1)

#### Anonymous Coward | about a year and a half ago | (#42474201)

The paradox is resolved by understanding temperature through its more rigorous definition as the tradeoff between energy and entropy, with the reciprocal of the temperature, thermodynamic beta, as the more fundamental quantity."

Translation for non-physics geeks: There are some slight differences in how we can define 'temperature', and Kelvin's definition of Absolute Zero is not exactly correct in all cases.

As my physics teacher told me once, "There is no such thing as a paradox. If your results appear to be a paradox, then you've done something wrong, defined something wrong, observed something wrong, or understood something wrong. Or any combination of the above."

But as for why this is news, it's because they've done this at the atomic level, previously this was confined to the sub-atomic level.

### Re:better explanation (3, Insightful)

#### Sockatume (732728) | about a year and a half ago | (#42473851)

Surely it's more important that technical terminology be technically correct than intuitively graspable? There's a reason that computer techs don't refer to the whole computer as the "hard drive", even though that's obviously exactly where you put all your files when they're on the computer.

LUDICROUS SPEED!

### Re:better explanation (2)

#### tgd (2822) | about a year and a half ago | (#42474153)

It seems to me to be a retarded description, like calling infinity + 1 a negative number.

They need to use a proper name for it, not something that only makes sense if your the kind of person that likes to say things in such a way that no one else understands what you mean just so you can claim its technically correct with a smug attitude.

Just means the computers the Matrix is running on happen to use signed values.

### Re:better explanation (1)

#### JasterBobaMereel (1102861) | about a year and a half ago | (#42474167)

It's all a trick due to the weirdness of quantum states trying to be defined in classical terms

They change the quantum state of atoms with almost no energy, to a higher energy state and keep them there using less energy than the change in state ... so in classical terms the energy had to come from somewhere and so the average temperature must have gone down.... but the missing energy is not really missing and the real temperature is still positive ...

### Re:better explanation (5, Insightful)

#### serviscope_minor (664417) | about a year and a half ago | (#42474391)

This is one of the things I love about slashdot. People with no knowledge of a subject call professionals "retarded" and get modded insightful.

It seems to me to be a retarded description, like calling infinity + 1 a negative number.

They need to use a proper name for it,

How about "nagative temperature". That's a proper name for it.

Temperature is defined by energy and entropy. Add energy and the entropy increases. That means the temperature is positive. How positive is how big that change is. Nice, straightforward, works well. Does whay you expect.

Then some quantum physicists discovered that adding energy makes the entropy go down. Well, plug that into the definition of temperature and the number comes out negative.

So basically, what you are claiming is that physicists are retarded because you don't like how the maths work out and you would rather they change the perfectly good classical definition of temperature to fit your sensibilities.

Deal with it. Quantum physics is very strange and many ideas you bring with you from the classical world simply don't work.

That doesn't make the professional physicists retarded, by the way.

### Re:better explanation (5, Funny)

#### Rhaban (987410) | about a year and a half ago | (#42473557)

So, temperature uses unsigned floats?

### Re:better explanation (5, Interesting)

#### Anonymous Coward | about a year and a half ago | (#42473611)

Is this proof of a simulated universe?

### Re:better explanation (1)

#### mrbluze (1034940) | about a year and a half ago | (#42473689)

Maybe it's an imaginary temperature?

### Re:better explanation (0)

#### Anonymous Coward | about a year and a half ago | (#42473743)

No, it's proof of a non-infinite, negative temperature beyond infinite temperature.

What???

### Re:better explanation (2, Insightful)

#### should_be_linear (779431) | about a year and a half ago | (#42473831)

There cannot be any proof, it is obviously impossible to distinguish between "simulated" and "real" reality

### Re:better explanation (1)

#### marcello_dl (667940) | about a year and a half ago | (#42473903)

Bingo. Not from the inside of it anyway.

Anyway there is no wrap-around in temperature, as I read the explanations, and without wrap-around it is difficult to go on and say "it smells like" a simulation.

OTOH genesis 3:22 speaks about obtaining root privileges so Eden appears as a simulation with bad security, ain't that interesting.

### man pages (4, Funny)

#### jabberw0k (62554) | about a year and a half ago | (#42474275)

You mean -- The serpent offered Eve a Perl script to parse /etc/passwd, and Adam's punishment was crypt (3) ...?

### Re:better explanation (1)

#### wonkey_monkey (2592601) | about a year and a half ago | (#42474033)

There cannot be any proof, it is obviously impossible to distinguish between "simulated" and "real" reality

Not that obvious to me. You're assuming the simulators have made a perfect simulation, which they may not have done. Or they could leave deliberate clues, if they so wished, which would help us distinguish simulation and reality. Of course, on a broader philisophical point, you could argue there would still be no difference - reality could be a simulation and still be real. http://www.technologyreview.com/view/429561/the-measurement-that-would-reveal-the-universe-as-a-computer-simulation/ [technologyreview.com]

### Re:better explanation (4, Funny)

#### Savage-Rabbit (308260) | about a year and a half ago | (#42474119)

There cannot be any proof, it is obviously impossible to distinguish between "simulated" and "real" reality

Not that obvious to me. You're assuming the simulators have made a perfect simulation, which they may not have done. Or they could leave deliberate clues, if they so wished, which would help us distinguish simulation and reality. Of course, on a broader philisophical point, you could argue there would still be no difference - reality could be a simulation and still be real.

Hi there,
You can stop philosophizing, I just deleted that guy from the simulation, he was getting annoying. Incidentally, if you subscribe to the specific flavor of mass delusion you guys call 'Christianity' and are wondering when the rapture will happen, it'll come the day I finally slip up while combining wild-cards and the 'rm' command on my Simulatron 6000 (TM).

Sincerely,

### Re:better explanation (1)

#### ScaledLizard (1430209) | about a year and a half ago | (#42474349)

OK, please refrain from hacking and crashing our simulated universe. Thank you.

### Re:better explanation (3, Funny)

#### Anonymous Coward | about a year and a half ago | (#42473645)

No, the temp was calculated with the original Pentium!

### Re:better explanation (5, Informative)

#### locofungus (179280) | about a year and a half ago | (#42473687)

It's a quirk of the way the temperature scale was defined.

One possible definition of temperature:

Put lots of little magnets in a magnetic field. They will line up with the field. At absolute zero there will be no (technically minimal[1]) deviation from them all being perfectly aligned. As you warm them up they will start to be less and less well aligned until at what we call infinite temperature, there is no alignment with the field at all and the alignment is completely random.

But, if instead of warming them up, you flip the magnetic field they will then "cool" through "infinite" temperature.

If we use this definition of temperature then it would make more sense to have absolute zero as negative infinite temperature, infinite as zero and still hotter temperatures as greater than zero.

This makes the unreachability of absolute zero make more sense. "Infinite" temperatures (and greater than infinite) are only unreachable via trying to add more heat.

Lasers utilize population inversion - which is a state that is impossible via naive thermodynamics and also does not have a sensible temperature as a result.

[1] Zero point energy.

Tim.

### Re:better explanation (0)

#### Anonymous Coward | about a year and a half ago | (#42473767)

why not just say that absolute zero is different than originally given? Science changes dates of origin of things all the time, Duh

### Re:better explanation (1)

#### Anonymous Coward | about a year and a half ago | (#42473865)

To me this seems like an overflow error. Once again proof that our universe is just another simulation on some basement dwelling alien's Beowulf cluster.

### Re:better explanation (0)

#### dissy (172727) | about a year and a half ago | (#42473875)

It seems this is a very specific quantum mechanical perversion, and no classical systems can reach the state quantum physicists call "negative temperature".

Indeed, classically speaking that would be the same as claiming that each and every last atom in the substance slowed down so much that they all came to a complete stop (aka zero degrees K), and then after being fully stopped, continued to slow down even more (aka below zero K)

### Re:better explanation (3, Informative)

#### Prof.Phreak (584152) | about a year and a half ago | (#42474371)

they all came to a complete stop

which (seems nobody mentioned this) violate quantum mechanics in a very big way.

### Re:better explanation (5, Informative)

#### cgaertner (1004238) | about a year and a half ago | (#42473881)

It seems this is a very specific quantum mechanical perversion, and no classical systems can reach the state quantum physicists call "negative temperature".

This is by no means a quantum perversion, just a natural consequence of the definition of temperature as 1/T = dS/dE. There's nothing mysterious about negative temperatures from a thermodynamical point of view, it just happens that calssical systems don't exhibit this property because they do not come with an upper limit on energy, whereas there are quantum ones that do.

The common interpretation of temperature as average energy per degree of freedom comes in via the equipartition theorem, but breaks down in various edge cases, eg when the energy levels cannot be approximated by continuity (eg heat capacity of diatomic gases) or for non-ergodic systems (some plasmas, I believe).

As to the problem of infinite temperature: In a sense, thermodynamic \beta = 1/kT is the more natural measure of hotness and coldness and has a pole at T = 0. Coming from T > 0, this corresponds to infinite coldness, whereas coming from T < 0, this corresponds to infinite hotness.

### Re:better explanation (2, Funny)

#### Anonymous Coward | about a year and a half ago | (#42474737)

Hotness frequently dances around a pole.

### Another reason to ditch quantum mechanics (-1)

#### Anonymous Coward | about a year and a half ago | (#42474113)

Particles traveling in negative time for instance, they don't, anymore than lightning travels up into the sky. We observe the effect of their interaction with matter, not the particle itself. The effect can certainly travel backwards. Lightning appears to go up because it ionizes the air on the way down, not enough to create observable light. Once the arc to the ground is made, the discharge is rapid and we see a flash, starting first at the ground and heading up. The reason it appears to go 'up' is because the mechanism we use to observe it (in this case our eyes) has a lower threshold. If we were quantum physics, we could claim the lightning travels backwards in time up into the sky. Yet we have electronics to analyze what happens, an no, the unobservable first part of the discharge is sky to ground.

Single photons in two places at once, (the classic two slit single-photon interference). Yet we can only detect photons due to electron promotions, so we could never detect the half photons, so we build models as though the photon (the thing we observe) can't exist in partial forms. But what we call a photon is just an effect we observe of something else, our model describes the effect not the thing causing the effect.

And negative temperature, well build your equations around it if you will, but you're basing the energy of your 'particles' on a probability of their energy density. If you have more energetic ones and overall the temperature is just above absolute zero, then theoretically some of those must be at a negative temperature.... Well either that or our particle isn't.

Negative temperature is just another indicator of the broken model, quantum mechanism is bunkum.

### Re:Another reason to ditch quantum mechanics (1)

#### Anonymous Coward | about a year and a half ago | (#42474619)

. Yet we can only detect photons due to electron promotions, so we could never detect the half photons, so we build models as though the photon (the thing we observe) can't exist in partial forms

I wonder if you are the same AC that posts this every other topic on quantum mechanics, or if multiple people think that is how things work. It has been repeatedly pointed out that this is incorrect, there are ways to detect photons that are non-destructive and ways other than using electron transitions. There are non-discrete ways of detecting photons in common use.

Also, if you are basing your bashing of quantum mechanics on the idea of negative temperature, then you have really no idea what you are talking about. Negative temperature is a classical concept and does not require quantum systems to implement or demonstrate. There are examples of quantum systems that produce it much as there are examples of quantum systems reproducing just about any aspect of classical mechanics.

### Re:better explanation (1)

#### slashmydots (2189826) | about a year and a half ago | (#42474575)

How about you instead explain in normal people terms (or at least computer specialist terms) how atoms can have less motion than not moving at all, because that sounds completely made up and impossible.

### Re:better explanation (0)

#### Anonymous Coward | about a year and a half ago | (#42474609)

How is this sub-zero temperature being measured?

### Not specific to quantum mechanics (0)

#### Anonymous Coward | about a year and a half ago | (#42474659)

Negative temperature is a concept from classical thermodynamics and there are classical systems that exhibit it. Quantum systems just give more options and variety for finding more examples.

### Re:better explanation (0)

#### Anonymous Coward | about a year and a half ago | (#42473589)

Oh, right. So there's an overflow when we add one to +inf, and it goes back to -inf. Standard two's-complement arithmetic with the catch of infinite binary digits. Quantum computing at its best :)

(AC because I don't remember my credentials here at work. tzot.)

### Re:better explanation (0)

#### Anonymous Coward | about a year and a half ago | (#42473685)

The main problem here is that temperature T is not the right physical quantity. The right physical quantity is the inverse temperature =1/T :

- = + infinity (T=0+) : infinite cold : the sytem is frozen in its state of minimal energy.
- >0 (T>0) : the system favors its less energetic micro-states
- =0 (T=+infinity=-infinity) : the system is uniformly distributed along its micro-states.
- 0 (T0) : the system favors its more energetic macro-states -
- = - infinity (T=0-) : infinite "hot" : the sytem is "frozen" in the state of maximal energy.

Note that the ordering in is logical, contrarily to the non-sensical ordering in function of T.

### Re:better explanation (1)

#### Anonymous Coward | about a year and a half ago | (#42473721)

Phew, if that was a better explanation, I am glad I, as a self respecting Slashdot reader didn't RTFA. Anyway, since nobody has yet given us a car analogy I thought I'd start on that.

The wiki says "T = dq[rev]/dS" where T is temperature and dS is the entropy. As we can see, temperature is inversely proportional to entropy.

So in car analogy this is like if you ride your car down the street in a real hot summer day with your air condition on. When I say "ride", of course you are in a queue, so you barely move. In your dashboard you have a few wunderbaums, some car registration forms, your toothbrush, a couple of mints and a few other important items stacked together. You used to have a system, but your gf messed it up. This is your entropy. Now, you need to find your tickets for the game fast. What you can do then is open the window of the car, which makes the inside of the car warmer, which in turn decreases the entropy, therefore making it easier to find your tickets.

I think I have a good start here, but it seems a bit... unfinished. Can anyone help me to improve this to make it also cover the subzero Kelvin part ?

### Re:better explanation (0)

#### Anonymous Coward | about a year and a half ago | (#42474041)

Your girlfriend will let you go to the game on your anniversary when hell freezes over.

### Re:better explanation (0)

#### Anonymous Coward | about a year and a half ago | (#42474593)

Phew, if that was a better explanation, I am glad I, as a self respecting Slashdot reader didn't RTFA. Anyway, since nobody has yet given us a car analogy I thought I'd start on that.

The wiki says "T = dq[rev]/dS" where T is temperature and dS is the entropy. As we can see, temperature is inversely proportional to entropy.

So in car analogy this is like if you ride your car down the street in a real hot summer day with your air condition on. When I say "ride", of course you are in a queue, so you barely move. In your dashboard you have a few wunderbaums, some car registration forms, your toothbrush, a couple of mints and a few other important items stacked together. You used to have a system, but your gf messed it up. This is your entropy. Now, you need to find your tickets for the game fast. What you can do then is open the window of the car, which makes the inside of the car warmer, which in turn decreases the entropy, therefore making it easier to find your tickets.

I think I have a good start here, but it seems a bit... unfinished. Can anyone help me to improve this to make it also cover the subzero Kelvin part ?

None of the cars are moving cause they are all stopped at a light. This light changes like a christmas tree at a drag strip, so everyone anticipates when the light will turn green and steps on the gas. Now all cars are still bumper to bumper but going 80mph.

A car in the oncoming traffic flashes its highbeams. The tickets stick to the windshield in front of your view. Mysteriously the mints and toothbrush have moved to the car next to you and back seat smells of dead cat.

### pump pump pump (-1)

#### Anonymous Coward | about a year and a half ago | (#42473491)

camels with a penis for a hump

### SONY RFID CDROMS - mark of the beast technology? (-1)

#### Anonymous Coward | about a year and a half ago | (#42473565)

TLDR: Mark of the Beast contender (RFID) makes way to CDROMS as method to communicate with hardware.
--
Examining Sony's Internet-free method for blocking used game sales

New patent filing describes using RFID chips to tie games to a single user.

by Kyle Orland - Jan 3, 2013 5:55 pm UTC

"A newly published patent application filed by Sony outlines a content protection system that would use small RFID chips embedded on game discs to prevent used games from being played on its systems, all without requiring an online connection. Filed in September and still awaiting approval from the US Patent Office, the patent application[1] for an "electronic content processing system, electronic content processing method, package of electronic content, and use permission apparatus" describes a system "that reliably restricts the use of electronic content dealt in the second-hand markets."

[1] http://www.freepatentsonline.com/y2013/0007892.html [freepatentsonline.com]

Used game sales continue to be a major concern for many big-name publishers and developers, who see the practice as a drain on the revenue they earn from selling new software. Sony's patent explicitly points out that suppressing the used game market will "[support] the redistribution of part of proceeds from sales of the electronic content to the developers."

The used-game blocking method described in the patent involves a "radiofrequency tag" and a type of programmable ROM chip that are paired with each game disc and can communicate wirelessly with the game system. The tag and chip can be used to store "unique information" about each console the game has been played on. Thus, when the game is used on a second system, the unique information stored on the disc can be compared to the information stored inside the new hardware, and in turn checked against "use permission" data stored on the EEPROM chip itself. As described in the patent, this "unique information" could be a system identifier or some sort of unique user ID that is somewhat portable between systems.

The patent describes users being asked to "pass the use permission tag over the RF reader/writer," suggesting some sort of near-field communication (NFC) area on the system itself that is used to launch this confirmation process. The patent also describes the RFID tag being used to decrypt content on the disc, which could provide a method for locking certain on-disc content to certain users who have unlocked or paid for the privilege. The system would theoretically also make game discs much harder to pirate, since illicit copiers would have to include correctly configured security chips in their copies, rather than using off the shelf media.

Of course, the fact that Sony has applied to patent this idea is a far cry from confirmation that this kind of protection system is in the works for the PlayStation 4. Even if it is, Sony could easily leave it to individual publishers to decide whether or not to implement it. In May, industry analyst Michael Pachter recounted a conversation[2] with SCEA president Jack Tretton where the Sony executive said he was "totally opposed to blocking used games."

It was about this time last year that rumors started to swirl that Microsoft was planning to block used games from being playable on the next Xbox. In March, similar rumors popped up surrounding the PlayStation 4[3], codenamed "Orbis" in leaked documents.

At the time, we examined some potential technical methods[4] for implementing this used-game blocking, including the kind of disc-linked solution being discussed in this patent. While this kind of resale-blocking technology would seemingly run afoul of the first sale doctrine codified into US law, legal experts seem unsure[5] about whether that doctrine would be enough to overcome the end-user license agreements common to video game sales. After all, the practice of restricting game resale is already taking root through the wide adoption of digital distribution, which prevents players from reselling downloadable games in almost all cases.

Now that Sony's patent has proven that the company is thinking about whether it could block used game sales, the question from the company's point of view becomes whether or not it should. While a total technical ban on used game sales across an entire console would have an effect on the market for new games, it's far from clear what that effect would be. The availability of cheaper used games does discourage people from picking up new games (GameStop alone sells roughly \$2 billion in used games each year), but the money or store credit players get from selling used games is usually plowed right back into buying more games[6], many of which are sold new. In a world in which all used video game sales were blocked through technical means, the new game market would quickly reach a new equilibrium of supply and demand for titles that are locked to a single system.

In the end, Sony's decision of whether or not to implement the idea outlined in this patent application will probably come down to the collective weight of two countervailing forces. On one side, there are the developers and publishers lobbying for tighter controls to protect their markets. On the other, there are players who might not be too keen on buying a system that can't play secondhand games (or on buying games that they'll never be able to resell)."

--
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### coincidentially (0)

#### Anonymous Coward | about a year and a half ago | (#42473649)

the mesaured temperature happened to be -2147483648

### Dark Energy (5, Interesting)

#### metamarmoset (2728667) | about a year and a half ago | (#42473671)

Observtions during the experiment could point to new research on dark energy.

From TFA:

Another peculiarity of the sub-absolute-zero gas is that it mimics 'dark energy', the mysterious force that pushes the Universe to expand at an ever-faster rate against the inward pull of gravity. Schneider notes that the attractive atoms in the gas produced by the team also want to collapse inwards, but do not because the negative absolute temperature stabilises them. “It’s interesting that this weird feature pops up in the Universe and also in the lab,” he says. “This may be something that cosmologists should look at more closely.”

### Re:Dark Energy (1)

#### michelcolman (1208008) | about a year and a half ago | (#42474319)

I was wondering where atoms would go if they would be repelled by gravity:

if part of the cloud is at a negative absolute temperature, some atoms will move upwards, apparently defying gravity

Here on earth, in most experiments we only have to consider the gravity of the earth because all other gravity will cause the same accelleration for earth as for our objects, apart from very minimal tidal effects, so we won't notice the difference. Sure, we're being centripetally accellerated towards the center of the galaxy, but so are the earth and the sun so we don't care. But what if you turn all gravitational attraction into repulsion? Those atoms would not only fly away from the surface of the earth, but also away from the sun, away from the center of the galaxy, away from other parts of our local cluster, etcetera. Which direction exactly would they end up accellerating in, relative to us? Could we even answer that question without an absolute reference frame in an infinite universe with gravitational attractions from just about everywhere?

And how exactly would you reconcile this with General Relativity? Gravity would no longer be equivalent to accelleration, but have the opposite effect. Mind you, it's not the atoms being pushed away by other atoms (like a helium balloon in a car which does indeed go forward during accellerations and backward when braking), but being pushed away by gravity itself! They will still act normally when their container is accellerated, unlike the helium balloon. Say bye bye to the very basics of GR.

### Your momma so fat even absolute zero shocked away. (0)

#### Anonymous Coward | about a year and a half ago | (#42473719)

Your momma so fat even absolute zero shocked away.

### Pff (-1)

#### Anonymous Coward | about a year and a half ago | (#42473741)

They know we don't understand anything related to quantum physics anyway, so they just make stuff up now!

### Older hardware (5, Funny)

#### alendit (1454311) | about a year and a half ago | (#42473761)

Sadly, our universe runs on a quite old hardware, which allowed the scientists to overflow the temperature variable. Why the Great Programmer didn't use unsigned longs ist beyond me, rookie mistake, really!

### Re:Older hardware (1)

#### Tom (822) | about a year and a half ago | (#42473905)

Since he is infallible, it is obviously a feature and not a bug.

Or, being omnipotent, he will simply declare it a feature.

And then he's going to be sued for copyright violation by Bill Gates. :-)

### The color-temperature of the universe? (1)

#### Paul Fernhout (109597) | about a year and a half ago | (#42474223)

Maybe because the Great Programmer wanted us to be able to use buffer overruns to invoke the debugger and thus do magic?
"I've thought about writing a sci-fi novel based around three interacting groups (taking off on Arthur C. Clark's ideas of any advanced technology is indistinguishable from magic):
* Those who have expanded human consciousness in a transhumanist technical nanotech/biotech direction and can do magical-looking things like with nanotech (like when nanites rebuilt the Red Dwarf).
* Those who have found this debugger link or just a bug and can affect reality in magical seeming ways (so, like Harry Potter or Earthsea, where words an incantations and symbolic movements and symbolic devices like wands are combined to create patterns that invoke complex programs written in arcane symbols, such as from "lumos" causing light to all sorts of complex spells invoked in complex ways -- maybe with a high degree of secrecy involved in who makes these things and who is told about them).
* Those who have just expanded humanity in a brute-force sort of way throughout the solar system and beyond through self-replicating space habitats duplicating themselves from sunlight and asteroidal ore, and maybe also have recently learned to tap zero-point energy and so create energy and matter in empty space (so, they can duplicate things out of thin vacuum as it were).
I have no idea where that would go. But those are the major sorts of "magic" things I can imagine in our future, and all are hard-sci-fi "plausible". Would the mystery of consciousness be an underlying theme?"

Or perhaps there are deeper aesthetic issues involved that we have only just begun to be aware of? :-)
"Still, ultimately, you may be right as far as there always being some issue to be in conflict about, and how on a cosmic scale, groups may well disagree fundamentally about things like enclosing stars. I'm also reminded of the Red Dwarf theme of David Lister's cat's descendants fighting over what color hats they should be wearing. :-) So, I'll go you one further -- are people going to fight over what color-temperature their local Dyson sphere should be tuned to? :-) Or even the color-temperature of the universe? Would you like a naturally balmy 2.725 K background temperature in the universe, or is that excessively wasteful and just an unasthetic looking color, and 2.724 K would be better? :-) Or maybe a slightly warmer 2.726 K would be worth it for making a peppier cosmos?"

### Simple (4, Funny)

#### famebait (450028) | about a year and a half ago | (#42473861)

Heat is just atoms moving around, after all, so negative temperatures are easy:
just make the atoms move backwards.

### Re:Simple (0)

#### Anonymous Coward | about a year and a half ago | (#42474125)

But what if they move sidewards?

### Re:Simple (0)

#### Anonymous Coward | about a year and a half ago | (#42474393)

Then you get buffer sideruns. Duh.

### Make it the new absolute zero! (0)

#### Anonymous Coward | about a year and a half ago | (#42473907)

Now that we've found a temperature colder than absolute zero, we need to adjust the scale so that zero is this new low.

Just recalibrate. Simple.

### The real question... (-1)

#### Anonymous Coward | about a year and a half ago | (#42473997)

The real question scientist need to look at here is can they use this gas to finally prove that greatest of scientific missions: That there is no God.

### I was right! (2)

#### mjr167 (2477430) | about a year and a half ago | (#42474029)

HAH! When I was a freshman in college a long long time ago, I lost points in a computer science assignment because I did not perform error checking to ensure the user enter temperatures were above absolute 0. Prof didn't believe me when I told her that wasn't a hard limit, so there!

### Does not compute (1)

#### Askmum (1038780) | about a year and a half ago | (#42474037)

Normally, most particles have average or near-average energies, with only a few particles zipping around at higher energies. In theory, if the situation is reversed, with more particles having higher, rather than lower, energies, the plot would flip over and the sign of the temperature would change from a positive to a negative absolute temperature

I'm sorry, but to me that is just absolute bollocks. So if you have more particles with a higher energy, you have a lower temperature? If I flip my thermometer upside-down, I'm also measuring a decrease in temperature when I heat it up. That makes sense too.

### Re:Does not compute (1)

#### serviscope_minor (664417) | about a year and a half ago | (#42474423)

I'm sorry, but to me that is just absolute bollocks.

Well, that's your problem, not the problem of physics. Try reading the wikipedia article on negative temperature.

### Sub Means below? (3, Interesting)

#### NSN A392-99-964-5927 (1559367) | about a year and a half ago | (#42474049)

So is this story misleading to say that absolute zero was achieved. Wikipedia The Celsius and Fahrenheit scales are defined so that absolute zero is 273.15 C or 459.67 F. https://simple.wikipedia.org/wiki/Absolute_zero [wikipedia.org]

But in the news story it says SUB and SUB means below, yet there is no mention of the temperature whatsoever in the article and going beyond absolute zero is not possible even out in space! You can get close, but not to absolute zero otherwise you would have created the ultimate weapon!

Enough said.

### Re:Sub Means below? (0)

#### Anonymous Coward | about a year and a half ago | (#42474139)

From the article: "This result, described today in Science1, marks the gas’s transition from just above absolute zero to a few billionths of a Kelvin below absolute zero."
Seems like a mention of temperature.

### Re:Sub Means below? (1)

#### NSN A392-99-964-5927 (1559367) | about a year and a half ago | (#42474287)

From the article: "This result, described today in Science1, marks the gas’s transition from just above absolute zero to a few billionths of a Kelvin below absolute zero."
Seems like a mention of temperature.

Well pointed out!

### ZPMs ? (0)

#### Anonymous Coward | about a year and a half ago | (#42474297)

This sounds like ZPMs - zero point modules - from Stargate.

### Maybe it's the 13 (1)

#### Impy the Impiuos Imp (442658) | about a year and a half ago | (#42474301)

Negative temperatures, vomiting robots, and "you're a snotty person" taxes on electric cars. 2013 is starting off just swell!

### right. (0)

#### Anonymous Coward | about a year and a half ago | (#42474359)

Sigh.... or the Kelvin scale is simply incorrect and does not reflect absolute zero. Damn scientist newbs.

### Hot angles (0)

#### Anonymous Coward | about a year and a half ago | (#42474605)

How many not so hot angles fit on the head of a pin head?

### Move Kelvin? (1)

#### PenguinJeff (1248208) | about a year and a half ago | (#42474795)

I thought if they have replicable results showing a lower temperature that they where suppose to update the Kelvin scales adjustment so that the lowest temperature is zero.

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