# Absolute Zero & Time

1. Jan 13, 2004

### JSK333

Hello,

I think of time simply as movement or distance traveled. No movement = no time.

Going with such a concept, could the inability to reach absolute zero explain our inability to manipulate time?

If at absolute zero, movement ceases, then time would also cease for that area.

What are your thoughts on this connection?

2. Jan 14, 2004

### Integral

Staff Emeritus
I know of no physical principles which say that time is dependent upon movement. We know that if something moves time must be passing, but that does not mean that if something does not move time does not pass.

3. Jan 14, 2004

### JSK333

If nothing moves, including electrons, protons, neutrons, then nothing changes--no aging, no degradation, etc. When nothing changes we have no awareness of timing passing.

At absolute zero, nothing moves/changes, correct? All activity stops.

4. Jan 14, 2004

### chroot

Staff Emeritus
As Integral said, there is no connection between movement and time. You are free to choose your coordinate system such that some object is at rest in it. In other words, you're always free to consider any object you wish to be absolutely at rest. Time, however, still marches on.

- Warren

5. Jan 14, 2004

### LURCH

I tend to dissagree. When we speak of time dilation, we mean the slowing of movement, provided that slowing is homogenous. If all movement ceases completely, then it can be said that time has infinitely dilated, or "stopped".

Or if one takes the thermodynamacist's definition of time, it is considered the increase of entropy. But again, if all movement ceases, entropy can no longer increase, so time must still be seen as "stopped".

6. Jan 14, 2004

### chroot

Staff Emeritus
The definition of time dilation makes no reference to movement at all.

The bottom line is this: I have a baseball. I can define a frame of reference such that in it the baseball is at rest. I will assign the baseball the spatial coordinates (0, 0, 0). The time coordinate is unaffected by my choice of spatial coordinates.

The definition of 'rest' is a relativistic one, and requires the defintion of an observer. The baseball may be at rest with respect to me, and not be at rest with respect to you. Does that mean that time stops for the object, or not? You're sitting in a chair right now. Your butt and the chair are at rest. Do your butt and chair experience no time?

- Warren

7. Jan 14, 2004

### JSK333

You aren't thinking it through as much as I have.

A chair is not a fundamental particle. It is made up of particles that are moving. Even if the "chair" is not moving, what makes it up is.

If each one was stopped, it would be at absolute zero, and there would be no movement. It would not age/degrade, because nothing is happening; i.e., no time.

Do you see what I mean now? Even what we think of being "at rest" is not truly at rest, because of its more fundamental makeup.

Last edited by a moderator: Jan 14, 2004
8. Jan 14, 2004

### chroot

Staff Emeritus
On the contrary, I've probably thought about it much more than you.

It doesn't matter whether the particle is fundamental or composite. You can just as well declare a frame of reference within which your favorite subatomic particle is at rest (or, at least, the peak of its wavefunction is).

Besides, it's a completely moot point. Absolute zero is not reachable, so it doesn't really matter what would or would not happen there -- it's not definable. I'm tempted to put this thread in Theory Development at this point.

- Warren

9. Jan 14, 2004

### JSK333

This is the main reason why I posted this, as I mentioned in the first post.

Since we are not able to reach AZ, could this also be why no one has been able to achieve time travel and/or a complete stasis field?

Question: why is AZ not reachable?

10. Jan 14, 2004

### chroot

Staff Emeritus
Time travel? Statis field? Off it goes.

- Warren

11. Jan 14, 2004

### JSK333

I mentioned manipulation of time in my first post.

Sorry if I chose the wrong forum. I thought Absolute Zero as the main subject would put it here.

12. Jan 14, 2004

### Loren Booda

Dynamics do not cease at absolute zero. For instance, spin-1/2 particles are in a nonzero minimum energy state there.

13. Jan 15, 2004

### dwf

the definition of time

Jsk33, your thoughts are very close to mine, but you should start to find a mathematical prove that time is dependent from energy and events.

I think this topic has to do with theory of groups and simmetry operations. For example, for the molecules in difusive movement, there´s no distinction between past and future. In my opinion, the only thing that can break this simmetry are referential events (so they could be used as a clock).

In absolute zero, there´s and even stronger simmetry. All operations are simmetrycal. You can´t say if time is moving or if it is stoped. The arrow of time disappear and time becomes an arbitrary variable.

Question: is entropy necessary for time to exist?

14. Jan 15, 2004

### Sariaht

It's true that in a referencesystem that's warm....
time passes slower...

and in a refferencesystem thats cold time passes faster.

but Dxobject within the referencesystem is 0 when T=O

But T is never 0 because of Heisenbergs relation.

And

Dx2passing + Dx2object is always c2t2.

15. Jan 15, 2004

### Loren Booda

So you are saying that if the average particle velocity v=(kT/m)1/2 (by Boltzmann) due to temperature is reduced, so is the passage of time? No wonder food keeps better in the refrigerator!

Remember though, that time is observer-dependent, so I guess if both the observer and object systems were composed of spin-zero particles at absolute zero, time might stop. Brrrrrr!

(By definition, observer-object interaction must actually involve both bosons and fermions.)

16. Jan 16, 2004

### Sariaht

DELTA = V

Let's say you made a neutrino stopp moving.

First off all, you would need to stopp it from moving h/(m4(pi)Vx) meters per second IN EVERY INSTANCE. The acceleration you would need to slow it down to lets say 0.5 m/s would make it grow more than 10 times it's own weight.