absolute zero

have they reached absolute zero yet? i heard that noone has been able to get anything to that cold.

and i was also thinking, if absolute zero does stop all movement/vibrations, then does that mean that electrons stop orbiting? because if it does, then wouldnt that mean that the van der waals forces in a covalent molecules would fall apart from each other? which would make what ever it is just break up or turn to liquid or gas or whatever (which would be the opposite of what would be expected since it would be below its melting point.

I am pretty certain that the LHC can achieve this. Otherwise, it is been only reproduced in some labs. *Shrugs*

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No: it is impossible. Very close, yes. Extremely close, as in millionths of a degree close, but actually there, no.

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Originally Posted by Photolysis

No: it is impossible. Very close, yes. Extremely close, as in millionths of a degree close, but actually there, no.

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do you mean it is physically impossible, or impossible because we dont have the technology yet?

and also, what about my thing about things breaking down/melting/boiling at absolute zero, if it were theoretically possible to get to absolute zero, would this happen?


and o'nus, how could colliding protons make something get to absolute zero?

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do you mean it is physically impossible, or impossible because we dont have the technology yet?

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Physically impossible, according to the laws of thermodynamics.

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i was also thinking, if absolute zero does stop all movement/vibrations, then does that mean that electrons stop orbiting? because if it does, then wouldnt that mean that the van der waals forces in a covalent molecules would fall apart from each other? which would make what ever it is just break up or turn to liquid or gas or whatever (which would be the opposite of what would be expected since it would be below its melting point.

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At absolute zero, the atoms would be at the lowest energy state, but they would still have some energy (the zero point energy). This is energy that cannot be taken away.

Molecules wouldn't fall apart simply because they would have no energy to do so. Breaking stuff requires energy. Stuff at absolute zero would be a solid. And yes, Van der Waal forces would definitely still apply.

Electrons don't orbit atoms; atoms are not really like a model of the solar system despite what it often taught to students beginning to learn science. They're essentially thought of as a field of charge and the energy state is basically the probability of it being in a certain region around the atom.

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Originally Posted by slash112

and o'nus, how could colliding protons make something get to absolute zero?

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The entire LHC is required to be at the right temperature to make the magnets become superconducters. Simply google "LHC Temperature" to see how much Kelvin it is at. It is not the colliding of protons that make temperature.. lol.

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Originally Posted by Photolysis

Physically impossible, according to the laws of thermodynamics.



At absolute zero, the atoms would be at the lowest energy state, but they would still have some energy (the zero point energy). This is energy that cannot be taken away.

Molecules wouldn't fall apart simply because they would have no energy to do so. Breaking stuff requires energy. Stuff at absolute zero would be a solid. And yes, Van der Waal forces would definitely still apply.

Electrons don't orbit atoms; atoms are not really like a model of the solar system despite what it often taught to students beginning to learn science. They're essentially thought of as a field of charge and the energy state is basically the probability of it being in a certain region around the atom.

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but i was taught in chemistry that van der waals forces come about due to the orbiting of the electrons. and if the electrons were to stop, then the dipole or whatever you call it wouldnt be there anymore.

i know it isnt like the solar system, i know that electrons have an orbit which goes against all previous theories untill quantum stuff. and you lost me when you went on about feild of charge etc.

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Originally Posted by O'nus

The entire LHC is required to be at the right temperature to make the magnets become superconducters. Simply google "LHC Temperature" to see how much Kelvin it is at. It is not the colliding of protons that make temperature.. lol.

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oh, woops.

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but i was taught in chemistry that van der waals forces come about due to the orbiting of the electrons. and if the electrons were to stop, then the dipole or whatever you call it wouldnt be there anymore.

i know it isnt like the solar system, i know that electrons have an orbit which goes against all previous theories untill quantum stuff. and you lost me when you went on about feild of charge etc.

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You're not listening to me. Electrons don't orbit. It's false. The model of the atom you got taught is not true at all. That's the very simple model.

And as I said, electrons will always have some energy, you can't take it all away, even at absolute zero.

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Originally Posted by Photolysis

You're not listening to me. Electrons don't orbit. It's false. The model of the atom you got taught is not true at all. That's the very simple model.

And as I said, electrons will always have some energy, you can't take it all away, even at absolute zero.

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ok, lets just forget that i was shown a picture of the model of an atom (which you claim to not be true), i keep hearing about scientists going on about "the orbit of electrons isnt what would be expected according to einstein.
since they refer to the orbit of the electron i assamed it exists

According to classical physics, i.e. 'Einstein', there should be orbits. But really there aren't at all.

Basically it's due to quantum physics, which Einstein never really accepted. The electron is moving around randomly about the nucleus so fast that you can't tell where it will be at any one time. All you can say is where it will probably be. Think of an electron round the nucleus as being a sort of 'cloud of possible electron coordiantes'. The following pictures are called orbitals, they show where certain electrons have a 90% probability of being found:

http://personal.tcu.edu/~mfanelli/im..._orbitals1.jpg

As a matter of fact the electron could be anywhere in the universe. It's just that it's extremely unlikely to be very far away from the nucleus.

dont you not think that:

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there should be orbits. But really there aren't at all

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contradicts this:

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The electron is moving around randomly about the nucleus

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and this:

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are called orbitals

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...no? An orbit is a (roughly) circular motion around a point. As I just said, the electrons do not even have a path, they are constantly instantaneously disappearing and simultaneously appearing at random points around the nucleus.

What are you talking about?

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Originally Posted by Xei

...no? An orbit is a (roughly) circular motion around a point. As I just said, the electrons do not even have a path, they are constantly instantaneously disappearing and simultaneously appearing at random points around the nucleus.

What are you talking about?

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oh, well ok, maybe so, but why is that thing called and orbital then, if its not an orbit.
(god, im really embaressing myself here, oh well i can try)

It's probably called an orbital as a relic of the outdated model of 'orbits'. But it is a misnomer.

You learn all about this in your first few lessons if you do A-Level (or I suppose Baccalaureate for you) Chemistry. I wouldn't recommend it though, pretty much everything else is numbingly dull.

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Originally Posted by Xei

It's probably called an orbital as a relic of the outdated model of 'orbits'. But it is a misnomer.

You learn all about this in your first few lessons if you do A-Level (or I suppose Baccalaureate for you) Chemistry. I wouldn't recommend it though, pretty much everything else is numbingly dull.

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oh right.

whats a "baccalaureate"?
we call A-levels advanced higher. and i asked my chemistry teacher if you learn about this stuff in advanced higher and she said yes. but i wont be doing that, i suck at chemistry, i just need to hope i scrape a C in the exam. (yes im that bad at it) i much much prefer physics.



and back to what im trying to make sense of, if electrons dont have an orbit, then how does van der waals forces work? (ill need to kinda ignore the answer for 2 more days though because i need to use what i was taught for my chem exam on wednesday. but im still curious)

I thought in Scotland you sat the International Baccalaureate instead of A-Levels... my mistake.

Basically with Van der Waals' you have two electron clouds in close proximity. Because they are negatively charged, one of them distorts the other so that the electrons have a higher probability of being further away. The result is that the distorted electron cloud is more positive on the side in the space between the two electron clouds, which in turn distorts that electron cloud so it is more negative on the side of the space between the two, so then you have two slight positive and negative charges which attract each other.

I think it's largely mathematical though.

oh i see, i suppose its not too far away from what i was taught. you one just makes more sense. thanks

and was photolysis correct when he said that electrons movement cannot be stopped by absolute zero.

oh and i was also wondering, out in deep deep space, if there was a place so far away from any heat source, would there be no heat energy? and would the temperature be absolute zero if that was so?

Photolysis is correct.

It's complicated as to why, and you can research it if you want to, but it is indeed physically impossible.

i just dont understand why everything else stops moving exept electrons, they must defy every scientific law/theory in the universe.

No the nuclei are vibrating too.

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Originally Posted by Xei

No the nuclei are vibrating too.

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wow seriously? but what is it that vibrates/moves at room temp which is stopped by absolute zero?

Everything would stop at absolute zero, because temperature is a measure of the kinetic energies of the constituent particles. However, absolute zero is impossible to achieve.

It would require infinite energy to achieve the temperature of 0 Kelvin or absolute zero.

However we can get pretty close :)

Doesn't heisenberg uncertainty say that absolute zero is impossible? The particles would have to have exactly zero velocity, but they must have some velocity if they are dancing about with an infinitely uncertain position: proof by paradox. Or at least I think that was the argument...

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Originally Posted by RedfishBluefish

Doesn't heisenberg uncertainty say that absolute zero is impossible? The particles would have to have exactly zero velocity, but they must have some velocity if they are dancing about with an infinitely uncertain position: proof by paradox. Or at least I think that was the argument...

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actually that makes sense. you see i thought it was the other way round, i thought it was that if you cool something to absolute zero everything stops, not you need to make everything stop to make it absolute zero.

but that really does clear everything up in my mind now, because as xei said, temperature is a measure of the kinetic energy of the particles.