Behavior of systems near absolute zero

[alpha2cen]

Is it possible to flow electric current at 0.0001K? Is electron movement an energy?

Edited February 11, 2011 by alpha2cen

[lemur]

Also if all the particles in the system got to the same 0 energy state, wouldn't that violate impenetrability? Maybe that's a more accurate reason why 0K doesn't occur. There would always be forces resisting the particles from occupying the same space of 0 energy.

Are you basically saying that the electrons repel each other due to same-charge, so as long as there is electrostatic force attracting them centripetally toward the nucleus as well as same-charge repulsion causing invigorating their orbital motion, they would maintain some level of energy? That is interesting because I have always read/heard that there is no physical reason to prevent the electrons from descending into the nucleus in any planetary/Bohr-type model, but it seems logical in this example that the centripetal attraction of the protons' positive charge would cause the electrons to draw increasingly nearer to each other is they occupy spherical planes of decreasing area. Since the electrons would repel each other more and more often within a smaller sphere-area, their speed would increase thus increasing their momentum in resistance to falling into the nucleus. It's as if the electrostatic same-charge repulsion of the electrons would translate the electrostatic attraction of the nucleus into the momentum that keeps the electrons "orbiting" at a certain radius from the nucleus. Or am I overextending the logic of what you said?

[swansont]

Is it possible to flow electric current at 0.0001K? Is electron movement an energy?

 

In principle, yes. Energy ≠ temperature. Having the current flow in a superconductor would give you no resistive heating.

[alpha2cen]

In principle, yes. Energy ≠ temperature. Having the current flow in a superconductor would give you no resistive heating.

Near oK

Which energy is related to temperature?

Total Energy = Particle mass energy + others

Which one is low energy state between divided particles and combined particles at the molecular level?

[swansont]

Near oK

Which energy is related to temperature?

Total Energy = Particle mass energy + others

Which one is low energy state between divided particles and combined particles at the molecular level?

 

Temperature is the average atomic vibrational/translational kinetic energy.

[steevey]

It doesn't "get" the energy from anywhere. It's just that the energy of the particle cannot be precisely determined, so it might just have enough energy to get out. And occasionally it does.

 

But the energy is what's being more precisely determined. 1/1,000,000,000 of a degree above absolute zero is pretty determined.

[Cap'n Refsmmat]

Good luck trying to constrain and measure the kinetic energy of every particle in a large system that accurately.

[steevey]

Are you basically saying that the electrons repel each other due to same-charge, so as long as there is electrostatic force attracting them centripetally toward the nucleus as well as same-charge repulsion causing invigorating their orbital motion, they would maintain some level of energy? That is interesting because I have always read/heard that there is no physical reason to prevent the electrons from descending into the nucleus in any planetary/Bohr-type model, but it seems logical in this example that the centripetal attraction of the protons' positive charge would cause the electrons to draw increasingly nearer to each other is they occupy spherical planes of decreasing area. Since the electrons would repel each other more and more often within a smaller sphere-area, their speed would increase thus increasing their momentum in resistance to falling into the nucleus. It's as if the electrostatic same-charge repulsion of the electrons would translate the electrostatic attraction of the nucleus into the momentum that keeps the electrons "orbiting" at a certain radius from the nucleus. Or am I overextending the logic of what you said?

 

I'm still considering the wave mechanics of the standard model. You can't have an equilibrium between no energy and something else to get no energy, but scientists didn't use that to cool atoms down to form bose-einstein condensation, they did a series of other things such as using magnetic fields and lasers tuned to the same frequency in a system of multiple particles. At that point, the atoms are in their lowest energy state that's been discovered so far. But, the reason that a substance can't be at 0K is because the waves of the atoms would all have the same properties making them violate impenetrability. But also, even when an electron is a wave, charge still matters. It's still a thing. An electron doesn't fall into the nucleus though because its a wave which has its existence in specific areas. It's not to say the charge of particles don't matter. In protons and neutrons, even though they are waves and I think entangled, they still have color charge to attract each other and that changes with each individual quark.

 

Good luck trying to constrain and measure the kinetic energy of every particle in a large system that accurately. People have gotten substances to be only one billionth of a degree above absolute 0 and they won the Nobel prize for it.

People have gotten substances to be one billionth of a degree above absolute zero/0K and won the Nobel prize for it. I think it was bose-einstein condensation oddly enough.

Edited February 12, 2011 by steevey

[Cap'n Refsmmat]

People have gotten substances to be one billionth of a degree above absolute zero/0K and won the Nobel prize for it. I think it was bose-einstein condensation oddly enough.

Sure. But temperature is an average value, and some particles in the system will inevitably have higher energies than others. Hence the uncertainty in energy, and hence my comment of "good luck constraining the kinetic energy of every particle in a large system".

[swansont]

I'm still considering the wave mechanics of the standard model. You can't have an equilibrium between no energy and something else to get no energy, but scientists didn't use that to cool atoms down to form bose-einstein condensation, they did a series of other things such as using magnetic fields and lasers tuned to the same frequency in a system of multiple particles. At that point, the atoms are in their lowest energy state that's been discovered so far. But, the reason that a substance can't be at 0K is because the waves of the atoms would all have the same properties making them violate impenetrability. But also, even when an electron is a wave, charge still matters. It's still a thing. An electron doesn't fall into the nucleus though because its a wave which has its existence in specific areas. It's not to say the charge of particles don't matter. In protons and neutrons, even though they are waves and I think entangled, they still have color charge to attract each other and that changes with each individual quark.

 

Impenetrability? If that's supposed to refer to the Pauli exclusion principle, it only applies to Fermions, not Bosons.

[alpha2cen]

But the energy is what's being more precisely determined. 1/1,000,000,000 of a degree above absolute zero is pretty determined.

 

Theoretically 0K easy to describe. But how to measure 0K is not easy.

And, Is the measured 0.1K really 0.1K? There was no discussion about near 0K temperature measuring. We only believe their data. How to and why the temperature is 0.?K??

[steevey]

Sure. But temperature is an average value, and some particles in the system will inevitably have higher energies than others. Hence the uncertainty in energy, and hence my comment of "good luck constraining the kinetic energy of every particle in a large system".

 

The uncertainty doesn't cause the higher energies, its the result of lower energies because your determining the energy more. I can get how under the uncertainty principle that it will inherently have a less determined position, but I don't see how it gets the energy to have a less determined position to carry it to the next energy level.

 

Impenetrability? If that's supposed to refer to the Pauli exclusion principle, it only applies to Fermions, not Bosons.

 

So two bosons can occupy the same space? Like two electrons can have all of the same properties?

Edited February 13, 2011 by steevey

[Cap'n Refsmmat]

The uncertainty doesn't cause the higher energies, its the result of lower energies because your determining the energy more. I can get how under the uncertainty principle that it will inherently have a less determined position, but I don't see how it gets the energy to have a less determined position to carry it to the next energy level.

Uncertainty isn't required for the first part of my statement. Temperature is average, and some particles will be hotter than others. That's just how temperature works; no uncertainty principle required.

 

Now, I don't think that at low temperatures you know the energy with higher certainty. You'd only know that if you tried to measure an individual atom's kinetic energy.

[steevey]

 

Now, I don't think that at low temperatures you know the energy with higher certainty. You'd only know that if you tried to measure an individual atom's kinetic energy.

 

Well your more precisely confining the measurement of energy when you move from something like 33 degrees to .00000000000000001 degrees. It's the same way that I more precisely confine the specific area in which light travels through, therefore making its direction less determined (which has been done).

[Cap'n Refsmmat]

Well your more precisely confining the measurement of energy when you move from something like 33 degrees to .00000000000000001 degrees.

How? Temperature is an average; any individual atom can have a range of energies inside the material. Changing the average doesn't affect that. The only way to constrain an individual atom's energy is to observe it with greater precision than it was observed before.

[alpha2cen]

Well your more precisely confining the measurement of energy when you move from something like 33 degrees to .00000000000000001 degrees. It's the same way that I more precisely confine the specific area in which light travels through, therefore making its direction less determined (which has been done).

 

Low temperature energy measurement is more difficult.

For example

0......1.....2.......3.........4......5.........6 hr

0......0......1......0.........0......0.5.......0K signal

Which degree is it?

At the low temperature the rate to the thermal equilibrium is very low.

Edited February 13, 2011 by alpha2cen