What 'Negative Temperature' Really Means 204
On Friday we discussed news of researchers getting a quantum gas to go below absolute zero. There was confusion about exactly what that meant, and several commenters pointed out that negative temperatures have been achieved before. Now, Rutgers physics grad student Aatish Bhatia has written a comprehensible post for the layman about how negative temperatures work, and why they're not actually "colder" than absolute zero. Quoting:
"...you first need to engineer a system that has an upper limit to its energy. This is a very rare thing – normal, everyday stuff that we interact with has kinetic energy of motion, and there is no upper bound to how much kinetic energy it can have. Systems with an upper bound in energy don’t want to be in that highest energy state. ...these systems have low entropy in (i.e. low probability of being in) their high energy state. You have to experimentally ‘trick’ the system into getting here. This was first done in an ingenious experiment by Purcell and Pound in 1951, where they managed to trick the spins of nuclei in a crystal of Lithium Fluoride into entering just such an unlikely high energy state. In that experiment, they maintained a negative temperature for a few minutes. Since then, negative temperatures have been realized in many experiments, and most recently established in a completely different realm, of ultracold atoms of a quantum gas trapped in a laser."
Layman (Score:4, Insightful)
I do not think this word means what you think it means.
Re:Layman (Score:5, Funny)
layman
n.
A man who gets laid. Also known as a non-Slashdotter.
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or maybe it does
you will never know until you look inside the box... errr RTFA
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What, you couldn't understand that? It's perfectly simple! Here, let me summarize: words words words words spin words words words negative words words words FRICKIN LASER
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Re:Layman (Score:4, Informative)
Here's my take on a layman explanation:
It's a water model in the classical world. It doesn't model everything from the quantum world, but makes it easier to understand the concepts.
Imagine a long vertical tube, closed off at the bottom.
When it's empty, it has minimal entropy (a measure for the amount of disorder).
When you add an amount of water (which models energy here), the water level rises and so does the entropy.
Now the definition of temperature is amount of heat energy per amount of entropy (T=dQ/dS). In the above situation, both amounts are positive, so the temperature is also positive.
Now imagine we close off the tube at the top too. This will leave an amount of air trapped there.
When we add an amount of water (using a valve to make sure the air doesn't escape), at first the system will behave exactly the same.
But when the water level gets near the top, the air gets pressurized and starts pushing back. And this increasingly so until it's almost full.
If we would make a hole in the middle of the tube, the water would squirt out until a pressure equilibrium was reached. We could extract work from this, to power a little water wheel. This means the "full" state had a lower entropy than the "middle" state.
So in this system, entropy went from a low value to a certain (maximum) higher value, and then back to a low value. This for an increasing amount of water (low, medium, max).
So what does this mean for temperature as defined above?
We kept adding the same amount of water (dQ in our model).
The change in entropy (dS) this caused is the slope of a hill (low, max, low), so at first it is a positive amount, which gets smaller and smaller, to become zero at the equilibrium point. After that, adding more water (energy) will cause the entropy to go down again, so dS will become a small negative amount at first and a larger negative amount near "full".
When we plug this in in the equation for temperature (T=dQ/dS) we get:
Going from "empty" to "middle": dQ is positive and the same, dS is positive and gets smaller, approaching zero. So T starts at some positive value, then gets higher and higher approaching positive infinity.
Going from "middle" to "full": dQ is still positive and the same, the change in entropy dS is zero at first and then becomes smaller and smaller (negative). So T starts out at negative infinity and then gets higher and higher approaching some negative value.
This illustrates how the temperature scale goes for increasing heat energy: ... +inf -> -inf ... -0
+0
So a system with negative temperature has more energy than the same system with any positive energy.
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So a system with negative temperature has more energy than the same system with any positive temperature.
FTFM :)
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Now the definition of temperature is amount of heat energy per amount of entropy (T=dQ/dS).
My version of the "laymans explanation" would revolve around that. There are several ways to define temperature, or at least several equations from distant corners of physics with a "T" in them where a bit of algebra can isolate that "T" to the left side all alone. At "normal human temperatures" those different ways to calculate a "T" all match up. Hopefully you're not surprised that at extremes of size (like astronomically large or atomic small) or extremes of ... (dramatic pause) temperature ... the eq
now this IS news for nerds (Score:1)
kudos souskill
Less uncommon than the name suggests (Score:1)
At least nowadays. Plenty of lasers around.
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Plenty of lasers around.
No, lasers are not an example of negative temperature.
For a thermodynamic system, zero temperature is when you can't vary (as in... decrease it) the internal energy of the system, the order of system is maximum.
For a "negative temperature system" (no longer a thermodynamic one), this translates into "after a point, one can no longer pump energy into the system, the order has reach the maximum". This does not happen into a laser.
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For a thermodynamic system, zero temperature is when you can't vary (as in... decrease it) the internal energy of the system, the order of system is maximum.
For a "negative temperature system" (no longer a thermodynamic one), this translates into "after a point, one can no longer pump energy into the system, the order has reach the maximum".
This is ... inexact.
A zero temperature system is one where energy fluctuations are zero. Or, if you want the third principle definition, is a system with zero entropy. This will immediately tell you why you cannot reach absolute zero - you have to lose not only thermodynamic fluctuations, but quantum ones as well, which is impossible.
A negative temperature system, otoh, is one where you have a population inversion on the energy level distribution. The elementary case is a 2-level system where the higher energy level has a higher occupation than the lower one. In order to follow the appropriate statistical distribution (M-B, B-E or F-D, depending on the system) the temperature has to be negative. The transition happens through the point of equal occupation, which corresponds to 1/T = 0, so T "wraps around" through infinite temperature (a theoretical construct, as you pointed out further down in the thread).
What you are describing is a system who has *all* its components in the higher state (so that no more energy can be pumped, as there's nothing left to absorb it). This is indeed a case of negative temperature, but a trivial writing down of its distribution will let you know that you are at T = -0 (or 1/T = - infinity), which is as impossible to achieve in practice as the T = +0 case.
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Practically speaking, if you are operating in a regime where multiphoton absorption is not relevant, you won't be exciting anything significant to higher states, which is quite possible in some laser setups.
Practically speaking, one doesn't need the "negative temperature" concept to design/built/operate a laser.
From a more theoretical standpoint, you can just consider the populations in the states desired and treat the rest as the external environment, if done carefully.
Yes, but in this case, "negative temperature" becomes a theoretical construct. At most, something to make the theoretical formalism easier to operate (e.g. for example, involving complex numbers in singal processing or quaternions in dealing with 3D transformations).
Otherwise, there would be no negative temperature systems anywhere, as any experiment if you add enough energy, the whole apparatus would be excited into a state of plasma and there would be no upper bound on energy in any system. All that is really matters is that statistical mechanical models using negative energy are relevant to this systems as being used.
Agreed. But you need to admit the fact that "negative temperature" is rather a theoretical artefact - it's not that one would use a thermom
Uhhhh (Score:4, Interesting)
This doesn't really help. I pondered this for a while the other day when I read that first and gave up trying to wrap my head around it. I was always under the impression that 0 kelvin (absolute 0) meant a state at which there was no movement at the atomic/subatomic level. It would seem as though to reach a negative temperature, one would have to slow a substances particles to less than 0 movement. Then I realized they were talking about a quantum state and I pretty much gave up trying to understand it at that point, because anything which has the word 'quantum' in it suddenly defies all the rules I'd ever been taught about anything at all. :o)
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Did you know that that idea is doomed to remain a purely hypothetical supposition, since (without a re-definition of 'black hole') there is utterly no way to test the idea??
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oh so light can escape a black hole given its not exceeded a condition, but that doesn't sound as scary
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So, you never got it past the event horizon, eh?
Re:Uhhhh (Score:5, Insightful)
All quantum means is that energy can only have specific values. Imagine a stereo with a volume knob that clicks between values, ie it can be 1, 2, 3, n, but cannot be anything inbetween those numbers. Now you have a quantum volume knob.
Temperature is a statistical property of matter that only exists once we consider things as a continuum. At scales where we consider quantum mechanics, a molecule has energies (kinetic, rotational, vibrational, electrical, etc) which can only take on specific values (quantized) and these values are specific to the atom/molecule to some degree (atom makeup, radiative properties, etc).
That probably doesnt help wtih the sub-0 part of the article, but perhaps it will help with the quantum part.
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awesome, im totally buying that $2500 quantum volume knob from Monster Audio now. I bet it sounds amazing!
Re:Uhhhh (Score:4, Funny)
Hah, already got one. It goes to 11.
Re:Uhhhh (Score:5, Funny)
Mine's even better, it goes to -1...
I don't use it anymore after I damaged physical reality on its first use.
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Huh? What? Can u type a little louder? Can't read you.
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"It's very special, because as you can see, the numbers all go to -1, right across the board".
Comment removed (Score:5, Insightful)
Re:Uhhhh (Score:5, Informative)
The short answer is that physicists throw out the "temperature describes amount of molecular movement" definition and replace it with something more abstract.
The abstract definition of temperature allows negative values, and that's ok because nobody cares anymore about molecular movements in that case.
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The original meaning was the average speed of the molecules in a sample of matter - not atoms or subatomcs particles. Since speed is the length of a velocity vector, it cannot be negative, and hence there is no such thing as a negative temperature. It's a shame that physicists were too lazy to invent a new word for "slope of the entropy vs. energy curve" and decided, instead, to recycle - and corrupt - the meaning of a
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The English word "temperature" was used in 1531 by Sir Thomas Elyot, long before Robert Boyle wrote The Sceptical Chymist. So how could that be its original meaning?
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The word "temperature" comes from the Latin "temperatura", which is still the same word in Portuguese, Spanish, and Italian. It comes from "temperare", which means "to season" (food). Much like you mix herbs and spices in your food to achieve a desired taste, you mix cold water with hot water to achieve a desired temperature.
Latin is only 2000 years old, I'm sure you could trace it back even further. The Proto-Indo-European root *tep- means "warm" (as in tepid), I'm not a linguist, though.
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Take the verb : evacuate. How many times have you heard "We needed to evacuate the people to a safe location"? The correct way is to say "The building was evacuated". You evacuate a building, not people. If you evacuated people, that would be quite disgusting.
The great thing about English is that you imply all that is missing to make the sentence make sense. "We needed to evacuate the people (from the building) to a safe location." The "from the building" is implied, and redundant in current usage. You aren't evacuating the people, the people are the subject of the evacuation.
But your way must be wrong if it prevents sentences like "The spectators were evacuated through the vomitoria."
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evacuate
/i vakyoo at/
Verb
1)Remove (someone) from a place of
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You would think a bunch of nerds would be too busy saying "ah, that is really cool" in response to learning some new amazing things the world is capable of, instead of clenching their ego in pain because something challenged what is taught in high school chemistry.
The thing is that the headline would have us think that the world just turned out to be capable of something amazing, because it would defy what was taught in high school chemistry, As in turns out, what was achieved has nothing to do with any mechanics taught in high school chemistry. So what you end up with us to groups of people. Those who discard the news value because "it doesn't do what they said it does!" and therefore refuse to be impressed, and those who understand the more advanced interpretation
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That still doesn't explain how in the fuck you get below zero movement, how can you move less than none?
Read the article for explanation. You indeed cannot have below zero "movement" or "jiggling". Negative temperature, says nothing about movement. That is the definition of temperature does not involve the amount of movement.
That is, Temperature is not exactly equivalent to a measure of movement; there are things stated to have temperature where no notion of movement occurs; things like the magnetic s
Temperature (Score:5, Informative)
Actually, it's not to hard to intuitively understand negative temperature if you think of it as something hotter than the hottest possible temperature. Classically, that isn't possible, but then you need a bit of quantum weirdness.
In a typical system of normal temperature particles of occupy various quantum energy levels available to them. In thermal equilibrium, statistically, lower energy levels tend to get occupied first and higher energy levels have fewer particles. If somehow you can create a stable system where higher energy states are occupied, but by some quirk (of quantum mechanics), lower ones are not, it turns out that is what a negative temperature system is.
As it turns temporarily creating a system where the higher energy levels are occupied before the lower ones is something that people do all the time to create a pumped laser. But lasers aren't designed to be a stable system (you eventually want the higher energy state to emit light/photons and fall to the lower energy state), so although the population of the energy states are inverted (more in the upper energy states), it's not stable, so it's generally not accurate to call this a negative temperature system.
The reason the "sign" of the temperature is negative is just a problem with the definition of temperature. For most defintions of temperature, if you add energy, you increase entropy, so temperature is a measure of how these relate to each other (the slope). If somehow when you add energy to your system, you decrease entropy of your system (e.g, you pack the upper energy states even tighter reducing entropy instead of just letting particles in all energy states into statistically higher energy states), the slope is negative.
Comment removed (Score:5, Informative)
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Temperature requires equilibrium, not continuum (Score:3)
Maxwell-Boltzmann statistics, and the field of statistical mechanics in general, work quite well with quantized systems. As an example, if you look at Boltzmann's definition of entropy: S = k ln W, where W is the possible number of microstates that can contribute to the system, you can see how statistical mechanics does a good job of handling quantized energy levels. Likewise, the Maxwell-Boltzman distribution does a fine job of describing the population distribution of an equilibrium ensemble of molecules
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Think of temp behaving as if it worked based on an absolute value (you know the whole |x| notation). As you add energy to a negative system (i.e. |-x+2|), it behaves as if you subracted energy from a positive one (|x-2|) because in absolute terms it is the same.
Not Helpful at all! (Score:1)
This doesn't really help. I pondered this for a while the other day when I read that first and gave up trying to wrap my head around it. I was always under the impression that 0 kelvin (absolute 0) meant a state at which there was no movement at the atomic/subatomic level. It would seem as though to reach a negative temperature, one would have to slow a substances particles to less than 0 movement. Then I realized they were talking about a quantum state and I pretty much gave up trying to understand it at that point, because anything which has the word 'quantum' in it suddenly defies all the rules I'd ever been taught about anything at all. :o)
That was my first reaction when I learned about quantum mechanics - nothing fundamentally works the way I was taught it works, it only appears to work that way under certain conditions.
Though, for this article, my first reaction was And the relevance of this discovery (again) is what, exactly? I didn't understand it before, I don't understand it now, and I don't see how it makes any difference what-so-ever.
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Sounds to me like absolute zero means absolute zero temperature. But objects at absolute zero still retain energy, other than kinetic energy. One you reach absolute zero, those objects dig deep to find energy to give away, somehow converting that energy into heat, or kinetic energy.
Maybe what we need here is a new form of measurement, something like "absolute energy" rather than "absolute temperature". If/when an object reaches absolute zero energy, what happens? I guess all the matter has been converte
Re:Uhhhh (Score:5, Informative)
The point they're making is that temperature can refer to energy and entropy other than just the kinetic motion kinds.
Unfortunately understanding the definition still doesn't get us very far for those of us without intuitive models of those other kinds of situations, so we're no farther ahead.
Re:Uhhhh (Score:5, Informative)
MOD PARENT UP (Score:2)
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This doesn't really help. I pondered this for a while the other day when I read that first and gave up trying to wrap my head around it. I was always under the impression that 0 kelvin (absolute 0) meant a state at which there was no movement at the atomic/subatomic level. It would seem as though to reach a negative temperature, one would have to slow a substances particles to less than 0 movement)
My understanding on negative temperature [wikipedia.org] without requiring QM:
1. in the classical thermodynamics and forcing the terms, the temperature is defined as "the measure of willingness of a system to un-aided transfer energy [wikipedia.org] to another system". If, when set in contact, two system do not exchange energy, they have the same temperature [wikipedia.org]. If one system spontaneously (i.e. not aided, without intervention) transfer energy to a second, then the temperature of the first one is higher than the second one
2. you need to adj
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Negative temperatures do not violate the third law of thermodynamics, and can still be considered a thermodynamic system. Moving the temperature of a system toward absolute zero still causes the entropy to approach a constant value, whether you do so from the negative or positive side.
That's what I said: arrange for some strange meanings of the temperature scale - this means you are dropping the "classical" view of the temperature ("a measure of atomic/molecular kinetic energy") and replace it with a "generalized" meaning, extended to be self-consistent across the positive and negative side of the scale. But in doing so, one should abandon any attempt to use the older/"classical" meaning on the extended side and embrace the new definition/concepts the extension requires.
One does not nee
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You're thinking of "temperature" as only being a measure of the (average) kinetic energy of a collection of particles. However, in physics, it has a more general definition.
So, the short answer to "it doesn't make sense to have less than zero motion" is that that's not what's happening at all. So no worries.
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I found this article, linked at the bottom of TFA, much easier to understand: Leprechauns and Laser Beams [coffeeshopphysics.com].
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It wants to get colder (Score:2)
Comment removed (Score:4, Informative)
What 'Negative Temperature' Really Means (Score:5, Funny)
In the USA, it means its really, really cold, you'll have to dress well, including good gloves and hat. If there is any wind you'll wand to cover your face too.
and the air is very dry, inside, getting a humidifier is a good idea.. If your car or truck has been parked outside for a while you would need to start it and have it warm up for 10 minutes before driving off.
In the rest of the world its cold but bearable, since its just below freezing sidewalks may be slippery.
You mean, Canadian temperatures ... (Score:1)
In the USA, it means its really, really cold, you'll have to dress well, including good gloves and hat. If there is any wind you'll wand to cover your face too. and the air is very dry, inside, getting a humidifier is a good idea.. If your car or truck has been parked outside for a while you would need to start it and have it warm up for 10 minutes before driving off.
In the rest of the world its cold but bearable, since its just below freezing sidewalks may be slippery.
So, what you're saying is that the canadian climate has below 0 temperatures for two reasons: The system of measurement is fundamentally flawed, and it's colder than we get in this area, normally.
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footpaths
Spritsmus!
Purcell and Pound (Score:5, Informative)
It would have been nice for Aatish to go a bit into what Purcell and Pound did in their 1951 experiment, namely "inverting" the orientation of the fluorine nuclei in the presence of an applied magnetic field by application of a radio frequency magnetic pulse, where the frequency is the Larmor frequency of fluorine and the pulse amplitude and length was sufficient to cause a 180 degree nutation. The result is that the nuclei have the same order (entropy) as the rest state, but have higher energy. In NMR, this is referred to as applying a 180 degree or pi pulse.
Aatish's comment about reality being liberal is unconvincing.
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Aatish's comment about reality being liberal is unconvincing.
Only to the part of the population that isn't the 47%.
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Now, I know there are some polls out there saying this man [President George Bush] has a 32 percent approval rating. But guys like us, we don't pay attention to the polls. We know that polls are just a collection of statistics that reflect what people are thinking in reality. And reality has a well-known liberal bias.
Stephen Colbert said this to President Bush's face at the 2006 White House Correspondents' Association Dinner.
The joke that "reality has a well-known liberal bias" has since taken on larger meanings about Republican/Conservative ideas and ideology being divorced from reality and reality being biased towards liberal ideas because liberal ideas are more in tune with facts. See Also: Truthiness
So why am I inventing this socialist utopia with rampant income redistribution? Itâ(TM)s because this is closely analogous to the physics of heat (as Steven Colbert put it, reality has a well know liberal bias).
Socialist utopia with rampant income redistribution = his physics analogy = reality
Does the joke make sense now?
blah (Score:1)
It just means the pressure pulls inwards rather than pushes outwards. Given given P=nRT, that would correspond to a negative temperature (since it means the pressure is negative (like a vacuum) and since n and R must be positive (being a count and a constant respectively), thus you can only get the negative sign from T (temperature). Never mind that baked into R (Rydberg Constant) there are assumptions that would exclude the current application and thus the "Negative Temperature" assertion, it's marketing,
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Who modded this shit up?
It is yet another person who refuses to read TFA and make random assertions.
It basically amounts to saying he doesn't believe in negative temperatures because he doesn't like how the maths works out. Suck it.
Oh, for fuck's sake. (Score:2, Insightful)
Here! [wikipedia.org]
a system with a truly negative temperature in absolute terms on the Kelvin scale is hotter than any system with a positive temperature. If a negative-temperature system and a positive-temperature system come in contact, heat will flow from the negative- to the positive-temperature system.
That a system at negative temperature is hotter than any system at positive temperature is paradoxical if absolute temperature is interpreted as an average internal energy of the system. 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. Systems with positive temperature increase in entropy as one adds energy to the system. Systems with negative temperature decrease in entropy as one adds energy to the system.
You add more energy, but the entropy doesn't increase. Gods damn that moronic blogger and his useless "tricks" metaphor. You don't "trick" shit you stupid fuck. You wouldn't say gunpowder "tricks" a lead projectile to scurry from the gun barrel if you were explaining a gun. We're not idiots, we just need to have the terms defined because some of us hadn't heard the term before in relation to absolute zero.
Protip: Next time you want to submit or vote up a "follow-up" fucking read the damn thing
Oblig (Score:1)
http://www.youtube.com/watch?v=xxa7Y1TLjas [youtube.com]
So... (Score:3)
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Ok i will give it my best shot (Score:5, Informative)
I thought about explaining it, and i will do so *without* mentioning the Dalai Lama.
The Situation is very simple: The definition of Temperature you learned in school, namely that it is only related to the average energy of many equal systems *is right*, but only for *classical systems*.
What does it mean?
If i have a classical gas, e.g. air at room temperature and i have to input to it, i can add this energy in whichever distribution i want. Easy to do that, no matter at which temperature we are.
No lets consider a quantum gas (to be complete: a quantum gas and not consiting of harmonic oscillators), e.g. electrons spins which are aligned to a magnetic field. Each of the electron can either have an Energy of -1/2E or +1/2E, where E depends on the electron spin and the magnetig field, but is constant. This means that if i have N electrons, we wont be able to input more energy than N * E into the system. Moreover if only a single electron in not in the high-energy state, we have to flip exactly this electron to get the system into its highest energy state. That may be pretty hard, statistically speaking.
So now imagine a quantum gas somehow statistically exchanging energy with a classical gas. That means, in our case, to bring the quantum gas to the state of Total energy = N*E (from the state of (N-1)*E) a high energy gas molecule would have the hit the very last of the low-ebergy electrons. If the high-energy molecules bounce from the electron in the excited state, then nothing will happen.
It is intuitive that, even if the two gases are in contact, the avergae energy between the systems will *not* be the same, just because its unlikely to flip *all* or *nearly all*.
The fromal version if this consideration is the textbook definition of the Temperature as a property in statistical physics, which is T=dE/dS, where E is the total energy and S is the Entropy (yes, the very same one as in computational science).
In the case of the two-level systems we find (let n be the numebr of systems in exited state)
S is proportional to -(n*log(n/N) + (N-n)*log((N-n)/n))
E is proprotioanl to n
That means that the sign of the temperature changes, as soon as more systems are excited than not.
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Potential Energies have an arbitrary reference point. Nothing in my argument changes if you replace -1/2E by 0 and 1/2E by E.
If you would not be an trolling AC you probably would have had the attention span to read the 2 paragraphs to the end and see that.
I have adopted a notation which is very usual in some areas of physics, most notably the situation when a two-level system is generated in a double-well potential and you want to express the truncated Hamiltonian in terms of standard pauli matrices, i.e si
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Well. I did. Although that was a german public school in the 12th grade, in the focused physics course. And 20 years ago.
The article links to a better explanation (Score:5, Informative)
There's a link in the article to Leprechauns and Laser Beams [coffeeshopphysics.com], which IMHO does a much better job of explaining things. As I understand it, negative temperatures don't just come from the entropy-based definition of temperature. You also need to be talking about a system whose energy content is capped. Normal materials don't do this -- you can keep adding energy (speeding up atoms) as long as you want. But if you have a group of atoms with exactly two energy states (high and low), once every atom is in the high-energy state you can't add more energy. Apparently, one example of this is a laser.
From an entropy point of view, the lowest energy and highest energy states have identical entropy (i.e. none -- one possible state). Entropy reaches a peak with half of the atoms in the high energy state, since this gives the largest number of possible atom state combinations.
Temperature is defined as the slope of the energy/entropy curve. The curve goes vertical at max entropy. If I understand right, at this point the temperature overflows like an integer variable, going from +inf to -inf and approaching zero from the negative end. (It's not really a continuous curve, but I don't know enough to guess at what difference that makes.)
So it sounds like the recent news about a negative-temperature gas was more about creating a new material with these sorts of quantum states. The negative temperature part caught the attention of the reporters (and the rest of us), but isn't the real scientific discovery. That's my reading of it, anyway.
The modern layman (Score:2)
Do they have one for something less than a layman? Perhaps one written for a complete ignoramus like myself.
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We're going to need James Cameron.
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We're going to need James Cameron.
Just because we're talking about below-zero temperatures doesn't mean we need to involve ice.
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I think you meant François Petit [wikipedia.org].
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To make it short, everything with more energy (should I say hotter?) than the most likely state has a negative temperature.
We down't move downward from zero, we get into the negative by moving upward.
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It's called 'mod down' not 'downvote' you idiot. Go back to fucking Reddit where you belong.
Re:Anthropomorphism (Score:4, Insightful)
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Yeah. Systems hate snobs and their feelings get hurt.
Re:Anthropomorphism (Score:5, Insightful)
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In fact we Physicist often anthropomorphize when talking amongst ourselves
Yes. It's a great shame.
Re:Anthropomorphism (Score:5, Funny)
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Yes, but over the past 50 years or so, physicists have started using a lot of wording like that. The problem is there are a lot more crackpots out there than their are reasoned intelligent individuals. You, being a physicist don't generally run into these people. I, on the other hand, have to deal with them daily. They know I have an interest in such things so they like to bounce their insane ideas off of me, and it's hard to argue logic with them when you use shitty wording like that. What that sentence im
Re:Anthropomorphism (Score:4, Insightful)
You, being a physicist don't generally run into these people. I, on the other hand, have to deal with them daily.
You blame a wording used to more conveniently convey a meaning, because you surround yourself with idiots.
It's not a physicists problem that you end up with uncool friends. Give it up, no amount of "correct" wording is going to make sane people out of crackpots. Your attempts to teach them logic are going to be futile no matter what (hey, you called them crackpots, and you're _still_ arguing with them). Just give it up dude.
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Re:Anthropomorphism (Score:4, Funny)
Systems with an upper bound in energy don’t want to be in that highest energy state.
Sigh...
Well, I concur, anthropomorphising these systems is a big problem.
You see: the matter and energy (no matter their colour - dark/white, orientation - up/down, flavour/charm/strangeness, etc) are freer and have more self-determination than any human being will ever have. They only obey the laws of physics, while the human beings need to obey heaps of others (e.g. did you ever see an electron being groped by TSA agents when passing through a semiconductor gate?).
Anthropomorphizing is degrading for physical entities and, for their sake, need to stop. Join the movement for upholding the inalienable rights of energy and matter before is too late!
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...It'll have something to do with Australia.
Everything on Slashdot has something to do with Australia, now.
Of course it will. Australia is the centre of the universe. Even the name "Aatish Bhatia" is obviously Australian in origin, and Rutgers is a suburb of Sydney I think.
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...It'll have something to do with Australia.
Everything on Slashdot has something to do with Australia, now.
Of course it will. Australia is the centre of the universe. Even the name "Aatish Bhatia" is obviously Australian in origin, and Rutgers is a suburb of Sydney I think.
Considering how "new" australia is as a country, it's not surprising that these things may appear to belong to other parts of the world. It's called intertexuality, and it's a natural process of borrowing ideas from established works.
Laws against intertextuality (Score:2)
It's called intertexuality, and it's a natural process of borrowing ideas from established works.
Until people start using copyrights and patents to suppress this process.
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...It'll have something to do with Australia.
Everything on Slashdot has something to do with Australia, now.
It has less than nothing to do with ...
Re:News For Nerds? (Score:5, Funny)
If 'nerds' had paid any attention to their thermodynamics/statistical mechanics class they would have already know all this and we would have been spared two frivolous posts in the front page.
Why are you being so negative?
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If 'nerds' had paid any attention to their thermodynamics/statistical mechanics class they would have already know all this and we would have been spared two frivolous posts in the front page.
Why are you being so negative?
Actually, s/he's beyond infinitely positive.
(as in: correctly stating the problem is, most of the time, a necessary step to solve it. As in: yes, there is a possibility to solve a problem without knowing about it, but what's the probability?)
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Wow.
Just wow.
OK, I understand not getting it first time around. It's /., who reads TFA, after all.
So after a bunch of random ignorance and denial, one of the editors actually does a follow up. And instead of reading that, youjust trot out the same old line again.
Seriously, dude, RTFA. It's all in there.