# Zero kelvin!

1. Sep 24, 2010

### tanzanos

If time requires movement in space time in order for change and hence time to occur then how does absolute zero in temperature effect time since no molecular or atomic movement is possible at such temperature?
Does vibration constitute movement that can affect time in relativistic terms?

Is it possible that a vibration equalling to the speed of light is possible with mass? If so how will this effect time regarding the mass?

2. Sep 24, 2010

### Kevin_Axion

Quantum Fluctuations always inhibit something from having a temperature of absolute zero.

3. Sep 24, 2010

### tanzanos

OK! Now what about achieving a vibration frequency equal to that of C. How will time effect the mass vibrating at such frequencies?

4. Sep 24, 2010

### Kevin_Axion

A vibrational frequency of c is impossible unless it is massless.

5. Sep 24, 2010

A vibrational frequency of c is impossible period. C and frequency dont have the same units, you cannot compare a speed to a frequency.

6. Sep 24, 2010

### karan1114

would 0 kelvin change the speed of light?

7. Sep 24, 2010

### Kevin_Axion

8. Sep 25, 2010

### tanzanos

Time is change and change is movement. Vibration is movement albeit a 'palindromic' one. If in theory one was to vibrate a mass at frequencies that translate to a movement almost the speed of C then will this effect the relativistic time of the mass?

9. Sep 25, 2010

### Drakkith

Staff Emeritus
I don't see how time requires movement in space for it to occur.

But if 0K did have an effect on time, then i would say that it would be the least relativistic that one can get. (If that makes sense)

10. Sep 25, 2010

### tanzanos

If I were to fly to the moon and back then that would constitute a cycle. If I were to do that repeatedly without interruption then that would constitute palindromic cycles and thus for all intents and purposes no different to any mass travelling to and fro repeatedly from point A to point B. Now if in all the cases the speed was approaching C then relativistic effects would occur. How is this any different to vibration of a mass; since in both cases one is moving atoms to and fro at relativistic speeds?

11. Sep 25, 2010

### Drakkith

Staff Emeritus
I completely understand and agree that vibrational energy could be considered a speed. Did you not understand what i was asking in my post?

12. Sep 25, 2010

### tanzanos

That is a possibility!

13. Sep 25, 2010

### Drakkith

Staff Emeritus
I was asking why time would depend on movement? Can time not continue forward if you have 0 movement?

14. Sep 25, 2010

### mikeph

I agree with that challenge... if nothing changes in a room, how does it affect time?

Does that make a clock stop in another room?

Without change you might not be able to infer time, but that doesn't mean it doesn't exist.

15. Sep 25, 2010

### pallidin

Right. Though time is an aspect of change, and that without change one cannot have time, one must take care to consider the "entire" system.
It is only when the entire system ceases to change in anyway that time itself can be considered to be completely stopped.

16. Sep 25, 2010

### mikeph

I disagree that it can ever be completely stopped. First, there is no reason to think the mere lack of motion of matter can stop time. We don't define it that way. Otherwise, if something stops moving, and stops time, how does it every start again?

Second, you are suggesting a local cause to a global phenomenon. Time is universal, though not universally constant, and the movement of matter is local. How is the lack of change in one part of space going to affect the flow of time in another part of space?

Third, the system can never be completely stopped, because of quantum fluctuations.

My opinion is that your personal definition of time might depend on change (which is very reasonable conceptually) but it does lead to such contradictions that you are currently arriving at.

17. Sep 25, 2010

### pallidin

It's NOT the lack of motion of matter that stops time, of course.
Rather it is the lack of change of EVERYTHING throughout the entire system that stops time, as time is a relationship and NOT an independent "force"

As you said, quantum fluctuations forbids this.
That was my point. One must cease change in the ENTIRE system in order for real time to stop. This is not possible as we currently know it.

18. Sep 25, 2010

### mikeph

If A then B,
but A is not possible.

So it is not meaningful to suggest that A causes B. You can't make a conjecture and then claim it's disprovability.

19. Sep 25, 2010

### pallidin

When A is impossible, any equation dealing with A is, by default, nonsensical.

20. Sep 25, 2010

### alxm

Both premises of this question are wrong. Neither time nor absolute zero are defined by motion.

The original poster, as well as Kevin_Axion, seem to be under the common, but false impression that absolute zero is defined as the temperature where molecules, atoms etc are stationary.

It isn't. You do not need to know anything about motion or atoms to define absolute zero. In fact, the earliest values of absolute zero were calculated well before the modern atomic theory was proposed by Dalton. You only need classical, pre-statistical, thermodynamics. Its existence and definition doesn't rely upon atoms or motion more than classical thermodynamics does, which is to say: Not at all. Classical thermodynamics also prevents you from attaining absolute zero.

Vibrational zero-point energy means molecules will not be stationary at absolute zero, not that they can't be at absolute zero (although they still can't for other reasons).