Relativity and temperature question

[Physicsguru]

Not necessarily. IF there is an increase in temperature in the moving frame, it is possible there may also a corresponding increase in the critical temperature. So the Meissner effect is preserved.

Creator

Yes necessarily. Tc is measured in the rest frame of the object.

Regards,

Guru

 

[K.J.Healey]

Yes necessarily. Tc is measured in the rest frame of the object.

Regards,

Guru

No, he was probably right. Theres a Tc and a Tmax that must both be measured for calculating the visible meisner effect. In the reference frame of the magnet/superconductor, it would be what you would expect. But if you were to observe it from a frame that views the magnet traveling at 0.8c, you would see the temperature of the system changed, as well as the necessary critical temperature.

You can't think of critical values as constants, the only one that is is "c" itself(and therefor mu and epsilon).

 

[gonzo]

I'm not sure how relevant this is here, but from just having read Taylor and Wheeler, isn't this all just handled by the 4-vector momentum-energy, which is always conserved in an isolate system?

Mass is invariant and the same in all inertial frames, and is the magnitude of the 4-vector. Somtimes part of this mass can come from heat. They say this specifically as an example, and even point out that in theory heat should be weighable. They even talk about the mass difference of water at different tempuratures, using celsius.

So, if temperature is just mass, then it would be seen differently in different inertial frames, since the *composition* of the 4 vector is different in different frames, although the magnitude is the same, right? Or maybe not?

They didn't really discuss this aspect in detail. But if you look at an object in a different inertial frame, it has different energy and different momentum, but isn't it's energy just equal to it's rest energy plus it's apparent kinetic energy in frame you are observing from? Which would seem to me to mean that temp. would be the same in all frames observing the object.

However, an isolated system *can* change tempurature. They give the example of an inelastic collision ... to objects smash into each other and stop. After the collision, the two objects are warmer and have greater mass from that. Kinetic energy has been converted into rest energy (which, of course, is just equal to the mass, since this is the case of zero momentum), which I guess is related to temp.

That was a lot of rambling...