Temperature and Time.

[Magnum GS]

I have been thinking for a while about the the value of 0 Kelvin. Having a temperature of 0 K means that there is no moleculer movement at all. I was just wondering this.
If the entire universe was at absolute zero would that mean that time would also stop? That is, if there is no movement anywhere wouldn't that just be like a snapshot in time (that could last forever) that can never move?

[QED Stepfiles]

I'm not sure if there's any physical meaning to this question, since zero kelvin is more of an asymptote that we can never reach than an actual physical quantity. It's sort of like asking "what would happen if we could travel at the speed of light?" Well, it's ultimately not a very useful thing to think considering our current model of physics suggests that something such as that will never happen. Divide by zero ftw.

That being said, temperature isn't really relevant to time. Just because something is moving more slowly does not mean that this something's perception of time is somehow altered. Just because there is no thermal energy for anything to happen does not mean that time is not proceeding normally while nothing is happening. So, no, I don't think it's very useful to make a comparison between temperature and time, because ostensibly there is no direct comparison (length and time, however, is a whole different story).

As my roommates and I like to say at times, your units don't work.

[Bynary Fission]

Well, to expand on what was said below, time is independent of any physical processes that occur in the universe - that is to say, it doesn't exist. It is a perception we as humans use to chart the length of something, how long it lasts, when in history we or something else is, etc. Physical processes stop, but time doesn't, being that it is technically imaginary (e.g if all clocks were to stop, time would not because it is independent of physical processes).

In a way, you could argue that time does stop at 0 K if you measure time by physical means - since time is also measured at the rate things change, advance, process, and occur, in a physical sense time would have stopped, but only in a perceivable manner.


~Bynary Fission

[ledwix]

Originally Posted by Bynary Fission

Well, to expand on what was said below, time is independent of any physical processes that occur in the universe - that is to say, it doesn't exist. It is a perception we as humans use to chart the length of something, how long it lasts, when in history we or something else is, etc. Physical processes stop, but time doesn't, being that it is technically imaginary (e.g if all clocks were to stop, time would not because it is independent of physical processes).

In a way, you could argue that time does stop at 0 K if you measure time by physical means - since time is also measured at the rate things change, advance, process, and occur, in a physical sense time would have stopped, but only in a perceivable manner.


~Bynary Fission

Time is relative, though, and two objects traveling at very different speeds with respect to one another are going to have very different perspectives on time in the physical world. Space and time, as we discovered in the 20th century, are intertwined into spacetime, meaning that time IS dependent on physical processes. What we should be getting at is whether time is the measure of change or simply the potential for change. But it certainly does exist.

If time does not exist, then we have no benchmark for what a schedule is. When you state where an object's location is, you need to locate its position in the x, y, and z physical directions. But time permits a sort of ambiguity in where an object is located, in that once you know the position of an object, you don't necessarily know where it will be the next time you look at it. We have to assign where it is in the t dimension. So it is because time exists that we have the ability to conceive of a schedule, not the other way around. (other way around meaning we "invent" time so that we can conceive of a schedule)

Anyway, it would take an infinite amount of time to reach 0K, because it's asymptotic. Total entropy can only equal zero after an impossibly large unit of time.

[Reach]

Well, I would argue Bynary Fission is definitely wrong; time does exist and is a necessary, fundamental property of the universe. Just as all objects have width or length component (which we measure arbitrarily), if General Relativity is correct, all objects also have a time component. Logically, one event could not transition into another without this component - the transference of energy within a system requires some bound on where and when it takes place. Otherwise, the universe would be an indeterminate chaotic mess where you could not differentiate one event from another (Potentially the state of the universe before the big bang?)

However, to deal with the actual question, absolute zero should not stop time. Energy, nor motion will ever completely cease at absolute zero, so assuming you don't remove space itself, time will continue to pass.

[Bynary Fission]

Originally Posted by Reach

Well, I would argue Bynary Fission is definitely wrong; time does exist and is a necessary, fundamental property of the universe. Just as all objects have width or length component (which we measure arbitrarily), if General Relativity is correct, all objects also have a time component. Logically, one event could not transition into another without this component - the transference of energy within a system requires some bound on where and when it takes place. Otherwise, the universe would be an indeterminate chaotic mess where you could not differentiate one event from another (Potentially the state of the universe before the big bang?)

I worded what I said sloppily. I'll address my viewpoint in a different manner to better illustrate it, since you've stated several points that are absolutely correct, and others that could be debated.

Let's bring out a hypothetical situation - everything in the universe has stopped. Nuclear reactions in every star in the universe stops, all living things freeze where they are, and the universe as a whole comes to a standstill. However, I am still aware of surroundings. I can see what lies in front of me, and I can sense the passing of time. Time has stopped - nothing is moving - physics no longer apply, as gravity and motion have ceased to exert any further effect - we remain where we lie. But yet, I can still sense time moving on. My thoughts go through my head as I wonder how long I've been sitting there, but indeed, time is still moving for me. Now take me out - time still moves, regardless of what is happening, because in the physical sense, time is no longer present. But in the mental sense (the kind humans use to measure dates, set schedules, etc) goes on.

The converse of this situation is what I am trying to get across - time does exist in a physical sense. For example, time affects how you versus everything else would perceive and see it at the speed of light. It affects how time (and space) change in approaching the event horizon in a black home, and on the list goes. But in the sense that most humans see it is, it doesn't. It's only a non-stop counter use to measure these physical processes.


I know - it's probably strange the way I'm seeing things. But to sum up what Ledwix also mentioned, time exists in a physical sense, but strictly a physical sense. I don't see it as existing other than in that fashion, since time as most humans see it was invented by us to measure events, to count the passing of days, and to measure our history in a way the human mind can encompass and perceive.


~Bynary Fission

[Reach]

Originally Posted by Bynary Fission

I worded what I said sloppily. I'll address my viewpoint in a different manner to better illustrate it, since you've stated several points that are absolutely correct, and others that could be debated.

Let's bring out a hypothetical situation - everything in the universe has stopped. Nuclear reactions in every star in the universe stops, all living things freeze where they are, and the universe as a whole comes to a standstill. However, I am still aware of surroundings. I can see what lies in front of me, and I can sense the passing of time. Time has stopped - nothing is moving - physics no longer apply, as gravity and motion have ceased to exert any further effect - we remain where we lie. But yet, I can still sense time moving on. My thoughts go through my head as I wonder how long I've been sitting there, but indeed, time is still moving for me. Now take me out - time still moves, regardless of what is happening, because in the physical sense, time is no longer present. But in the mental sense (the kind humans use to measure dates, set schedules, etc) goes on.

The converse of this situation is what I am trying to get across - time does exist in a physical sense. For example, time affects how you versus everything else would perceive and see it at the speed of light. It affects how time (and space) change in approaching the event horizon in a black home, and on the list goes. But in the sense that most humans see it is, it doesn't. It's only a non-stop counter use to measure these physical processes.


I know - it's probably strange the way I'm seeing things. But to sum up what Ledwix also mentioned, time exists in a physical sense, but strictly a physical sense. I don't see it as existing other than in that fashion, since time as most humans see it was invented by us to measure events, to count the passing of days, and to measure our history in a way the human mind can encompass and perceive.


~Bynary Fission

I'm not sure I understand your position; you state that time does exist in a physical sense (which was my entire point, so you're agreeing with me), but try to argue it does not in some other sense? It cannot exist and not exist. It either exists or it doesn't. If something is physical it has substance and existence, so you're going to have to clarify what you mean.

If you're trying to argue that it doesn't exist as something mental (Apparently non physical, according to you?), then ok, but that gets into something else entirely.


However, back to the initial topic; none of this changes my primary argument that 0 K would not stop time. Movement doesn't stop at 0 K, so regardless time still exists even using your (first) definition.

[Bynary Fission]

Originally Posted by Reach

I'm not sure I understand your position; you state that time does exist in a physical sense (which was my entire point, so you're agreeing with me), but try to argue it does not in some other sense? It cannot exist and not exist. It either exists or it doesn't. If something is physical it has substance and existence, so you're going to have to clarify what you mean.

If you're trying to argue that it doesn't exist as something mental (Apparently non physical, according to you?), then ok, but that gets into something else entirely.

This.

That's basically the point I was arguing - time may exist in a physical way, but the mental aspect of it that we as humans "created" doesn't really exist - it just serves the purpose of such functions as enabling us to chart the passing of days, to enable a tangible modern society to exist and function, etc.


~Bynary Fission

[Lipidman]

Originally Posted by Bynary Fission

Let's bring out a hypothetical situation - everything in the universe has stopped. Nuclear reactions in every star in the universe stops, all living things freeze where they are, and the universe as a whole comes to a standstill. However, I am still aware of surroundings. I can see what lies in front of me, and I can sense the passing of time.

Incorrect. You wouldn't be able to sense/see/feel/sensationalise anything under those conditions.

/nit pick :3

[devonin]

If such a thing were to happen, we couldn't think anything about it anyway. If the temperature of the universe were to somehow instantaneously reach absolute zero (And it would have to be both instantaneous and come from some magical impossible outside force [In order for it to happen naturally, my intuition is that we'd need every particle of matter to be infinitely far away from every other particle of matter, which would both take infinite time, and happen long after humanity ceased to exist] in order to actually happen instantaneously)

In such a case, to a magical outside observer who isn't bound by the laws of our universe, everything would appear to be frozen. To anything inside the universe, nothing would appear to be anything, because, well, everything would be frozen, which includes the various chemicals in our brains necessary for thought or awareness.

If things were then to go back to normal, not only would we not notice that anything had happened, from the perspective inside the universe, it would be the true case that nothing had happened. These stops and starts could be happening constantly and we have no way whatsoever to percieve them.

[igotrhythm]

Originally Posted by devonin

If such a thing were to happen, we couldn't think anything about it anyway. If the temperature of the universe were to somehow instantaneously reach absolute zero (And it would have to be both instantaneous and come from some magical impossible outside force [In order for it to happen naturally, my intuition is that we'd need every particle of matter to be infinitely far away from every other particle of matter, which would both take infinite time, and happen long after humanity ceased to exist] in order to actually happen instantaneously)

In such a case, to a magical outside observer who isn't bound by the laws of our universe, everything would appear to be frozen. To anything inside the universe, nothing would appear to be anything, because, well, everything would be frozen, which includes the various chemicals in our brains necessary for thought or awareness.

If things were then to go back to normal, not only would we not notice that anything had happened, from the perspective inside the universe, it would be the true case that nothing had happened. These stops and starts could be happening constantly and we have no way whatsoever to perceive them.

As scary as hell as the bolded portion is, I'd have to agree. I'm not 100% positive on this, but I believe at least one of the famous atomic clocks keeps track of time by using the metric definition of a second as the time it takes for an atom of a certain isotope of cesium to vibrate a certain number of times at a certain temperature.

Now think...if all motion in the universe were to stop (since we are at absolute zero), a second would thus be infinitely long to this magical external observer, but as pointed out, those inside the universe would have no way of perceiving it. We would not be frozen in time, for time itself has stopped in this universe, at least as far as the metric definition of the second (and thus all other measures of time) goes. But I agree, we would not be aware of it; however, this assumes that time continues to march on for the outside observer. It would perceive a snapshot of the universe at the state it was in when the temperature hit absolute zero.

I'm not sure about the stops and starts thing, though. (As long as we're postulating about magical observers that exist outside, and are thus not bound by the laws of, the universe we know...) If our universe were to suddenly go to absolute zero, what, then, would be the force that restores our universe to the state it was in before?

[Bynary Fission]

I'm aware such a situation is impossible (and contradictory) - hence why I stated it as hypothetical to aid in illustrating my point.

Originally Posted by igotrhythm

If our universe were to suddenly go to absolute zero, what, then, would be the force that restores our universe to the state it was in before?

Nothing. The universe would theoretically have perished by this time - nothing but black holes would remain as all stars (and galaxies, in turn) would have died and collapsed in on themselves (assuming this ever were to happen in the time span it could), creating a space of no life or light (and eventually, the black holes would disappear too, leaving nothing but protons). Then, in a-near infinite number of years (I forget the actual name of the measurement of time being described), the universe would have expanded so much that it eventually has a heat death or enters a universal state of absolute zero (assuming the universe is not a closed space, then the fate would probably be that it collapses in on itself in less time). But I digress. If this paragraph is completely incoherent and contradictory, it is likely because it's past 2 AM right now.

Damn, now this makes me want to talk about the end of the universe.


~Bynary Fission

[devonin]

Like I said above, the only "realistic" way for absolute zero to be achieved would require humanity to have long since been very very dead, so it isn't even really worth caring about.

It seems to me that the OP refers to a magical instant freeze which as I suggested would have to come from outside, and its effects on time.