I never knew there was a different zero than the zero on a scale. So more than -400+ degrees is absolute zero. Why??

Just like with mass, there are different units of measure. Absolute zero refers to 0 Kelvin, which is the point where all subatomic particles stop moving. It is equal to -273.15 degrees Celsius, and -459.67 degrees Fahrenheit.

So if I am dropped into liquid nitrogen and frozen, subatomic particles in my body are still moving?

So if I am dropped into liquid nitrogen and frozen, subatomic particles in my body are still moving?

Absolutely.

Note:

The point where all atomic motion is stopped. True absolute zero can never be reached though due to quantum effects (we would know the atoms exact position and momentum and this is verboten).

So if I am dropped into liquid nitrogen and frozen, subatomic particles in my body are still moving?
Not sub atomic. But yes, your atoms and molecules are still moving plenty.

and how does anyone know that?

and how does anyone know that?
What?

Know that subatomic particles are still moving in my frozen solid body

Know that subatomic particles are still moving in my frozen solid body
Quit saying subatomic. It's atomic. Subatomic are the particles that make up atoms, among other things.

Because you still have a temperature well above absolute zero when frozen in liquid nitrogen at ~ -196C. This is still "hot" compared to -273C.

Hey, IdleMind said subatomic. Is he wrong?

So a frozen person has never been sliced up and someone said "Yep, atomic particles are still moving"?

my particles are the same as water or plant particles? All stopping at the same temp?

Absolute zero is defined by the total lack of nett energy I think, which basically means that no movement can take place at that point.
Actually heat is a form of energy possessed by atoms or molecules by virtue of the vibrational movement.

so my completely frozen body and a rock give off heat?

Hey, IdleMind said subatomic. Is he wrong?
Yes, he's wrong.

So a frozen person has never been sliced up and someone said "Yep, atomic particles are still moving"?
Err... probably not...

my particles are the same as water or plant particles? All stopping at the same temp?
All molecules have a specific temperature at which they freeze. At room temperature, iron is frozen, while water is a liquid. At 0C, water will freeze.

Temperature is nothing more than a measure of the amount of kinetic energy the molecules in a thing posess. Solids, liquids, gases, and plasmas all have a temperature.

As you remove energy from a thing by lowering its temperature, you are slowing down the molecules. This is where absolute zero comes into play. How can anything move slower than dead stop? It can't. This is the temperature where all molecular motion is as stopped as it can be. Dead stop. Quantum issues can prevent you from getting to true absolute zero, but you can get asymptotically close.

Questions?

so my completely frozen body and a rock give off heat?
Absolutely.

I have one.. if at 0 K no nett energy is present how can matter still exist ?

I have one.. if at 0 K no nett energy is present how can matter still exist ?
No kinetic energy - energy of motion. Matter still has an energy equivalent of E = mc2 in it's rest frame.

No kinetic energy - energy of motion. Matter still has an energy equivalent of E = mc2 in it's rest frame.

So electrons never stop, not even at 0 K ?

...Quantum issues can prevent you from getting to true absolute zero, but you can get asymptotically close.

Questions?

what does asymptoblah mean? :o

Is there anywhere in the universe where its thought to be absolute zero?

So electrons never stop, not even at 0 K ?
No. Not that they are moving anyway in the way you might think of it. Electrons in orbitals are more like standing waves of probability than moving particles.

what does asymptoblah mean? :o

LMAO! :D

"Asymptotic" means that a quantity or a thing can get arbitraritly close to a reference but never get there. A nice way to visualize this is based on Zeno's paradox. You are 1 meter from a door. Take a step forward that's half the remaining distance. You're 0.5m away. Do it again, you're 0.25m away, then 0.125m and so on. You can take as many steps as you want and get as arbitrarily close as you want but can never actually reach the door (of course you have verryyy tiny feet...:D)

Is there anywhere in the universe where its thought to be absolute zero?
Well, nothing can get to true absolute zero, but there are a few places where it's theorized to be just a degree or so above (inside giant molecular clouds). Scientists have gotten atoms to within 0.0001 or so degrees of absolute zero in the lab.

thanks for not laughing at me...oh wait :p lol

so, where have they theorized?

thanks for not laughing at me...oh wait :p lol

so, where have they theorized?

Places like this, deep inside cold molecular clouds. They're all over the galaxy:

http://www.paulruffle.com/molecularclouds.htm

Until its proven, is absolute zero a theory?

Until its proven, is absolute zero a theory?
?

Umm... no. It's a fairly simple fact actually. It's been known since the discovery that molecules are little bits of matter, a century or so.

Nope. It's a real, basic, well understood and proven thing.

http://www.phy.hr/~dpaar/fizicari/kelvin.html

so the fact that there is an absolute zero is a given. Is the temp at which it is reached a theory?

so the fact that there is an absolute zero is a given. Is the temp at which it is reached a theory?

Nope. That's a solid fact also. Like I said, the only thing that prevents you from reaching true absolute zero is quantum uncertainty (and the funds from the NSF to push it that far. That's a joke...)

The theories behind this stuff are the atomic theory of matter and quantum mechanics. What they predict and are subsequently verified are scientific facts.

so what would happen to me if I reached absolute zero?

so what would happen to me if I reached absolute zero?

Some would say you're already there... HA! (sorry :()

You'd be very cold. That's really about it. Nothing else unusual. (of course you can't get to true absolute zero, remember?)

If I went into that cloud I could.

If I went into that cloud I could.
Nope. It's a degree or so above absolute zero.

Not being able to reach true absolute zero isn't just a matter of not trying hard enough, it's forbidden by the laws of the universe.

Laws don't change? Laws can't be wrong?

so pretend I got to absolute zero. What do you think would happen? Nothing? I'd just be super frozen?

Laws don't change? Laws can't be wrong?

Hmm... I suppose. But the laws we're talking about here are the most fundamental and well tested in all of science. Really. I kid you not.

so pretend I got to absolute zero. What do you think would happen? Nothing? I'd just be super frozen?
If you insist...

Since this would violate the foundations of physics as we know it, I'd say you would collapse into a singularity of improbability and ruin the day for many well paid quantum physicists.

Otherwise, yes. You'd just be super frozen.

No. Not that they are moving anyway in the way you might think of it. Electrons in orbitals are more like standing waves of probability than moving particles.

Aren't they more like standing waves of probability of moving particles ?
I fail to see how matter is held together at 0 K..

...Otherwise, yes. You'd just be super frozen.

see, was that so difficult. :shrug: :D
Thanks for answering my questions. :thankyou: I know it must have been exasperating for you.

Aren't they more like standing waves of probability of moving particles ?
I fail to see how matter is held together at 0 K..
Well, atoms are still bound to each other by valence electrons, even at absolute zero. Only the overall atomic motion is "stopped". When I say they don't move in a conventional sense, I mean they're not "orbiting" the way some think. They can't be moving in a nonuniformly accelerated way (i.e. circular orbits) because they'd radiate away their energy in a burst of photons and fall into the nucleus and there'd be nothing (electrons that are moving non uniformly radiate photons).

That's all I meant.

I know it must have been exasperating for you.
Nah. No prob.

Yust wondering but how would a particle behave if it got to -1°K.
would it radiate cold in stead? Would the atomic motion be reversed, would it get antimatter like characteristics?

Yust wondering but how would a particle behave if it got to -1°K.
would it radiate cold in stead? Would the atomic motion be reversed, would it get antimatter like characteristics?

That's a completely meaningless question. How can an atom or molecule be moving slower than "not moving at all" which is what -1K implies?

:confused:

And we normally don't say "degrees kelvin" or use the degree symbol. We just say "kelvins" or 273K.

That's a completely meaningless question. How can an atom or molecule be moving slower than "not moving at all" which is what -1K implies?
please note that I don't really know anything abouth the subject

But I wonderd if -1K would react similar like 1K so that it's spin would increase again (altough reversed) and would show share similar differences like matter Vs antimatter.
If it's not imposible in theorie Then would this particle gain energy when it's radiating it?

please note that I don't really know anything abouth the subject

But I wonderd if -1K would react similar like 1K so that it's spin would increase again (altough reversed) and would show share similar differences like matter Vs antimatter.
If it's not imposible in theorie Then would this particle gain energy when it's radiating it?
Well, if you read the thread, you'd know that temperature is a measure of the motion on molecules and atoms. And that "absolute zero" is where all motion stops. And therefore, speculating about what -1K (negative stop-ness???) means is meaningless.

Well, atoms are still bound to each other by valence electrons, even at absolute zero. Only the overall atomic motion is "stopped". When I say they don't move in a conventional sense, I mean they're not "orbiting" the way some think. They can't be moving in a nonuniformly accelerated way (i.e. circular orbits) because they'd radiate away their energy in a burst of photons and fall into the nucleus and there'd be nothing (electrons that are moving non uniformly radiate photons).

That's all I meant.

Sorry to nag you... lol

But 0 K is complete lack of energy right ?
How can anything be energetic at 0 K then ? No matter how electrons move, can't keep that up at zero energy, right ?

0K is yust as likly to achieve like c(lightspeed), you can get pretty close but you will never get there

0K is yust as likly to achieve like c(lightspeed), you can get pretty close but you will never get there

I know, it's the hypothetical point at which zero energy is achieved or something, right ?

0K is yust as likly to achieve like c(lightspeed), you can get pretty close but you will never get there
Exactly.

Sorry to nag you... lol

But 0 K is complete lack of energy right ?

No. It's a complete lack of kinetic energy associated with the molecules of the cold stuff.

How can anything be energetic at 0 K then? No matter how electrons move, can't keep that up at zero energy, right ?
Yes, they can. (just a reminder - 0K is theoretically impossible. 0.000001K is not)

The kinetic energy we're talking about is only about the movement of those atoms and molecules. The quantum behavior of the electrons in "orbit" around the atom is unrealted to the temperature of the atom as a whole. The atoms still share valence electrons so are still bound together in a normal way.

Think of it this way. You have a bunch of balls connected to each other with elastic in a Web-O-BallsTM. The web is on a big vibrating table. As the table vibrates, the balls are flung about, stretching the elastic. As you reduce the vibrations, the balls slow down and are pulled closer together (they "cool"). When you turn the table off (absolute zero) the balls are still there, still connected, and still in a web.

Yes?

I know, it's the hypothetical point at which zero energy is achieved or something, right ?
Huh? No. It takes more and more energy to get closer to c. Matter can only asyptotically approach c.

No. It's a complete lack of kinetic energy associated with the molecules of the cold stuff.


Yes, they can. (just a reminder - 0K is theoretically impossible. 0.000001K is not)

The kinetic energy we're talking about is only about the movement of those atoms and molecules. The quantum behavior of the electrons in "orbit" around the atom is unrealted to the temperature of the atom as a whole. The atoms still share valence electrons so are still bound together in a normal way.

Think of it this way. You have a bunch of balls connected to each other with elastic in a Web-O-BallsTM. The web is on a big vibrating table. As the table vibrates, the balls are flung about, stretching the elastic. As you reduce the vibrations, the balls slow down and are pulled closer together (they "cool"). When you turn the table off (absolute zero) the balls are still there, still connected, and still in a web.

Yes?

Yes, thanks for the example :)
So I guess it's safe to say that electron do not possess kinetic energy then ?

Huh? No. It takes more and more energy to get closer to c. Matter can only asyptotically approach c.

Huh? How did light speed get involved ?

Huh? How did light speed get involved ?
Post #46?

Yes, thanks for the example :)
You're welcome!

So I guess it's safe to say that electron do not possess kinetic energy then ?
When bound to an atom and in a ground state (not excited by outside sources), I would have to say, classically, no. I could be wrong, but I've never heard of bound electrons being described by anything other than their excitation states or potential energy.

Post #46?

Yes of course.. but that was a mere comparison.. never mind though

You're welcome!


When bound to an atom and in a ground state (not excited by outside sources), I would have to say, classically, no. I could be wrong, but I've never heard of bound electrons being described by anything other than their excitation states or potential energy.

Thanks :)

How does absolute zero work on PLASMA (The 4th state of matter)?

Liquid helium is fine below 1.K . Molecular motion is supposed to stop at 0.K but atomic motion continues, as in matter does not collapse and so cease to exist. This suggests that a "colder" temperature may be possible where all motion does cease.

How does absolute zero work on PLASMA (The 4th state of matter)?
Well, a plasma is a gas that has been heated to such temperatures that its atoms become ionized. i.e. some outer electrons become unbound and the "gas" is now electrically conducting. That's a plasma. So, as you cool the plasma, it will become a neutral gas again and then eventually a solid. So, it behaves just like anything else that you freeze. It just starts out one phase farther along than a neutral gas.

Liquid helium is fine below 1.K . Molecular motion is supposed to stop at 0.K
yeah but it stil freezes at 0.95 K what is still verry cold... makes you wonder could their be a element or a molecule that doesn't become solid when it reaches 0K?

yeah but it stil freezes at 0.95 K what is still verry cold... makes you wonder could their be a element or a molecule that doesn't become solid when it reaches 0K?
What is the definition of the word "Absolute"? And the word "Zero"?

Very interesting thread...

How can an atom or molecule be moving slower than "not moving at all" which is what -1K implies? Just a passing thought - what if it's gaining mass, so that more energy is required to get it back to +1 than was removed in getting it from +1 to 0 ?

Not serious ! Just consdiering - - -

What is the definition of the word "Absolute"? And the word "Zero"?Absolute: from the Latin: ab, and solutus, ab means from, or by (agency), or even after, solutus means unbound, free, or scattered. Zero comes from Greek, means zero.

There ye goest.

Originally Posted by superluminal
What is the definition of the word "Absolute"? And the word "Zero"? now what's the defenition of the word atom

negative kelvin might not be impossible even though I still have to finish reading the article
link (http://www.maxwellian.demon.co.uk/art/esa/negkelvin/negkelvin.html)

De le ted

Absolute: from the Latin: ab, and solutus, ab means from, or by (agency), or even after, solutus means unbound, free, or scattered. Zero comes from Greek, means zero.

There ye goest.

There ye GOETH. Asinus ad lyram

now what's the defenition of the word atom

negative kelvin might not be impossible even though I still have to finish reading the article
link (http://www.maxwellian.demon.co.uk/art/esa/negkelvin/negkelvin.html)

If you want to get esoteric about it, fine, but our common understanding and intuition about negative absolute temperatures is correct.

http://istd.gsfc.nasa.gov/cryo/introduction/neg_Kelvin.html

This sort of very specialized situation describes an abstract concept based on "population inversions" that I don't fully understand myself. It really has nothing to do with actual temperatures in normal systems.

This model even includes "infinite temperature" which, if you think about it, is physically impossible due to relativistic limitations (can't really have atoms moving infinitely fast, can we?).

Well, a plasma is a gas that has been heated to such temperatures that its atoms become ionized. i.e. some outer electrons become unbound and the "gas" is now electrically conducting. That's a plasma. So, as you cool the plasma, it will become a neutral gas again and then eventually a solid. So, it behaves just like anything else that you freeze. It just starts out one phase farther along than a neutral gas.

I think he meant the 5th state of matter - Bose–Einstein condensate.

I think he meant the 5th state of matter - Bose–Einstein condensate.
Hmm... Ok?

Well I think so because Bose–Einstein condensate like no other state is connceted with absolute zero.

By the way I think it's theoretically impossible to go lower than absolute zero,
at least not in our universe, or reach it for that matter.

Well I think so because Bose–Einstein condensate like no other state is connceted with absolute zero.

By the way I think it's theoretically impossible to go lower than absolute zero,
at least not in our universe, or reach it for that matter.
Right.

OK, so do any of you think Wolfgang Ketterle will eventually get absolute zero? I mean he got 810 trillionths of a degree above it.
Or, that is as close as we would ever want to come?

(and I am not understanding how he made the BEC at all. I mean really? Its not a gas, liquid or solid??? WTHell?!)

OK, so do any of you think Wolfgang Ketterle will eventually get absolute zero?
No, theoretically you can get very, very, very close, but not 0,000..., not in this universe at least.

At 170 nanokelvin atoms no longer behave like individual atoms, but due to quantum effects behave like one uniform wave. Fascinating really. There is nothing other like that in nature or in our human experience.

http://nlds.sdsu.edu/JPGs/double_oscillations_small2.jpg

BBC has a documentary "The race to absolute zero", you might want to see it.

http://www.mininova.org/tor/864833

There ye GOETH
Whither goest ye, ye GOETH?
Vades quosum, vadetis? Sic it adsumes.

No, theoretically you can get very, very, very close, but not 0,000..., not in this universe at least....

But I don't understand why?!

Universe is energy. Try getting rid of the universe.
Eventually you'll reach a point where extracting some particular ammount of energy would take 14bn years and a machine the size of the universe, and it doesn't stop there.

but aren't they trying to make a black hole in a lab? Why not absolute zero?

There's a fundamental theoretical and practical difference in the ammount of energy involved. Black hole doesn't mean getting rid of this universe.

Black hole doesn't mean getting rid of this universe.
Yeah yust this earth

Hang on everybody. Reality check.

You cannot even theoretically reach absolute zero because of a very fundamental feature of quantum mechanics. The uncertainty principle states that you can never obtain both the position and momentum of a particle to arbitrary precision simultaneously. The very act of pinning down one attribute (say momentum) means that you cannot know the position of the particle at all, and vice versa. This is a consequence of the fact that quantum particles really are more of a probabilistic combination of these attributes (and other quantum numbers like spin). By pinning down one precisely, the other goes out the window so to speak and becomes completely indeterminate.

So, true absolute zero implies that you would know the momentum of a particle (or a group of them) as being exactly zero, and the exact positions of the particles. This is a no-no. Not allowed. Can't do it.

I don't think anybody here is saying we can reach it. ;)

p.s. A joke question - could we reach it and not know about it? :D

I don't think anybody here is saying we can reach it. ;)

p.s. A joke question - could we reach it and not know about it? :D
Now that was funny! :D

My mechanic told me he was 100% certain what was wrong with my car. So I said that must mean he could tell me exactly what it was going to cost me. He said, no, that was forbidden by the fundamental laws of the universe.

:confused:

Apples and oranges. I don't think it is so. :)

Apples and oranges. I don't think it is so. :)
But it was funny, right? :shrug:

A bit. Yes. :)

My mechanic told me he was 100% certain what was wrong with my car. So I said that must mean he could tell me exactly what it was going to cost me. He said, no, that was forbidden by the fundamental laws of the universe.
The engine-space of your car will experience a wave-collapse, and no allowed harmonics will be admitted (i.e., will be forbidden states), once any required linear, distributive function--electric current, and hydrocarbon oxidation; no longer commute with any entropic cycle within the space.

As your mechanic says, this is not a random, or chaotic event, but the equivalent meaning in financial terms, unfortunately is.:confused:

The engine-space of your car will experience a wave-collapse, and no allowed harmonics will be admitted (i.e., will be forbidden states), once any required linear, distributive function--electric current, and hydrocarbon oxidation; no longer commute with any entropic cycle within the space.

As your mechanic says, this is not a random, or chaotic event, but the equivalent meaning in financial terms, unfortunately is.:confused:
Frud,

Is this meant as a joke in response to my joke? Please explain.

Thx,

SL.

It's only a joke if someone laughs. Otherwise it just falls over all alone in a forest somewhere.

*thud*