About time and absolute zero.

[MiranoPoncho]

This is a question that has been on my mind for a few days now and I am sure that someone here knows the answer. Here it is:

If time were to stop, would absolute zero be reached, and vice versa?

My thinking on this question is simple: if time were to stop, there would be no movement possible at any physical level, thus causing absolute zero. If someone could help answer, that would be great!

 

[Matthias99]

What, exactly, does it mean to "stop" time? How would you even be able to tell if time was slowing down or stopping, unless you are somehow able to be "outside" of the normal flow of time? Does being "outside of time" really have any meaning?

Sorry that I can't give you a real answer, but basically this is a philosophy question. While the rate of time passage is relative, special relativity also says that you can never completely "stop" it unless you actually have something moving at the speed of light (which would require an infinite amount of energy).

 

[Gibsons]

Originally posted by: MiranoPoncho
This is a question that has been on my mind for a few days now and I am sure that someone here knows the answer. Here it is:

If time were to stop, would absolute zero be reached, and vice versa?

My thinking on this question is simple: if time were to stop, there would be no movement possible at any physical level, thus causing absolute zero. If someone could help answer, that would be great!

Pretty good explanation here Text

 

[DrPizza]

well, if you define temperature as average kinetic energy...
and do 1/2 m v^2 for the particles, then I suppose we'd need to calculate the velocity of those particles...

and, since velocity = displacement divided by time,
:x Division by zero! edit: 0 divided by 0

Temperature would be undefined.


edit2: p.s. dividing by zero does not equal infinity... that occurs in calculus problems when you are *approaching* zero. i.e. what is the limit of 5 divided by x^2 as x ***approaches*** zero. The answer is that as x approaches zero, 5 divided by x^2 increases without bound i.e. positive infinity. Nonetheless, anything divided by zero is... undefined.

 

[TheoPetro]

Originally posted by: DrPizza
well, if you define temperature as average kinetic energy...
and do 1/2 m v^2 for the particles, then I suppose we'd need to calculate the velocity of those particles...

and, since velocity = displacement divided by time,
:x Division by zero! edit: 0 divided by 0

Temperature would be undefined.


edit2: p.s. dividing by zero does not equal infinity... that occurs in calculus problems when you are *approaching* zero. i.e. what is the limit of 5 divided by x^2 as x ***approaches*** zero. The answer is that as x approaches zero, 5 divided by x^2 increases without bound i.e. positive infinity. Nonetheless, anything divided by zero is... undefined.

im pretty sure i was conceived by dividing by zero

 

[silverpig]

The real answer is to look at the thermodynamics.

1/T = dS/dE

So 1/temperature (funny that the REAL thermodynamic quantity is the inverse of what we call temperature) is equal to the rate of change of entropy with respect to energy. Or, if you like:

1/T = dS/dt * dt/dE

This results back to our original equation. Since dS/dt is undefined for zero dt, the equation does not make any sense.

So what we can do now is look at how this equation behaves when we take different values for dt (ie, big, small...). You can see that the equation does not depend on time at all, so temperature is independent of the rate of passage of time. (dt/dt* I guess?)

 

[iamaelephant]

The notion of stopping time is nonsense. I don't know why you guys are bothering answering a question like this using the laws of thermodynamics or kinetic energy calculations. The question is just plain nonsense so there is no logical answer. It's like asking for the square root of -1.

 

[bendixG15]

Originally posted by: Falcon39
The notion of stopping time is nonsense.........................

This is the place for questions that are not logical...
For some its stupid..for others its chicken soup.

Lots of people like chicken soup

 

[iamaelephant]

I didn't say it's stupid, I said it's nonsense. As in, it makes no sense to ask the question. As I said in my previous post, it's like asking for the square route of -1. You can't answer a question that has no basis in reality. Nonsense.

 

[MiranoPoncho]

Perhaps not, but what about controlling ones perception and the flow of time?

 

[DrPizza]

Originally posted by: Falcon39
I didn't say it's stupid, I said it's nonsense. As in, it makes no sense to ask the question. As I said in my previous post, it's like asking for the square route of -1. You can't answer a question that has no basis in reality. Nonsense.

Actually, you might be living in the 1700's if you think asking about the square root of -1 is "nonsensical." Initially, as imaginary numbers were being studied by mathematicians, they were thought to be just that - imaginary, hence the name. They were studied for the mere fun of it. (True mathematicians enjoy studying and advancing mathematical concepts, regardless of their possible future application to anything. This is similar to why people climb mountains - because they're there.) Hopefully, you are aware that there are real applications (electrical engineering, for example) where the square root of -1 is used. I'll agree that it seems nonsensical, primarily because it's one of those things that falls outside the realm of our intuitions.

Here's another example: non-euclidian geometry. Back when (Bolya?) and (Lobachevsky?) were playing around with it, I'm sure a lot of people were of your mindset - it's nonsense. In non-euclidian geometry, the circumference of a circle divided by its diameter isn't equal to Pi. Nonsense. But, these guys were happy to work on the pure mathematics, without regard to it possibly having any application to the real world; past, present, or future. Then along came this dude named Einstein. He said something like "screw you guys, the universe doesn't follow Euclidean geometry. It's non-Euclidean." For this, he became famous. For something unrelated, he won the Nobel prize in physics and had lots of babes who are attracted to really smart guys. Then, at some point, there was a solar eclipse. Some scientist(s) did a little observing (Mercury had something to do with those observations) and they made a statement like this (but, probably not quite as succinct): "Holy sh!t, Einstein is right!"

Yeah, the universe is a pretty nonsensical place. Some of the greatest leaps in our knowledge haven't been made by going with the flow, but rather, by someone proposing something that seems to completely go against the grain of all our collective knowledge.
So, unless you have an absolute complete understanding of the concept of time; and I don't think anyone does... I don't think it's fair to tell the OP that it's non-sensical to ask the type of question he did.

 

[iamaelephant]

I get your point DrPizza, maybe I am being a little closed minded here (I'm familiar, on a very basic level, with non-euclidian geometry and Einsteins General Relativity). In all fairness, even if we were able to "stop time," how would we know if anything is at absolute zero?

Now, admittedly, yes if time were to stop then everything would be at absolute zero, as heat itself is nothing more than the random motion of particles and motion is distance travelled over time. But if there is no time then there could not possibly be motion.

Here's a spin off question for those interested or knowledgable in special relativity - when an object is moving very quickly relative to my inertial frame, time will be passing slower for them according to me. Does this mean I would also measure their temperature as being lower than if they were stationary (in my inertial frame), because the atoms that constitute the object are also moving slower, relative to if they were stationary?

 

[silverpig]

Originally posted by: Falcon39
I get your point DrPizza, maybe I am being a little closed minded here (I'm familiar, on a very basic level, with non-euclidian geometry and Einsteins General Relativity). In all fairness, even if we were able to "stop time," how would we know if anything is at absolute zero?

Now, admittedly, yes if time were to stop then everything would be at absolute zero, as heat itself is nothing more than the random motion of particles and motion is distance travelled over time. But if there is no time then there could not possibly be motion.

Here's a spin off question for those interested or knowledgable in special relativity - when an object is moving very quickly relative to my inertial frame, time will be passing slower for them according to me. Does this mean I would also measure their temperature as being lower than if they were stationary (in my inertial frame), because the atoms that constitute the object are also moving slower, relative to if they were stationary?

Nope.

 

[fsardis]

Originally posted by: Falcon39
I didn't say it's stupid, I said it's nonsense. As in, it makes no sense to ask the question. As I said in my previous post, it's like asking for the square route of -1. You can't answer a question that has no basis in reality. Nonsense.

the square root of -1 is i....

 

[AZReDWiNG]

As that link mentioned, even at absolute zero there is zero-point energy (E=mc^2 -- if something has mass, it has energy). If something has potential energy, it has the ability to do work and therefore the ability to move.

As for time.. This is off the subject a bit, but I found it pretty interesting. My physics teacher was giving a lecture about entropy and went on some tangent. If time flows towards the direction of entropy increase, then once the state of the universe is finally one of complete disorder, everything stops. Energy can no longer be transfered to anything else. You must do work to do ANYTHING -- including die, vaporize, whatever, it all takes work -- so everything stops. But then, the gravitational pull of everything on one another will create a singularity -- the opposite of the Big Bang. All the energy will collect back into where it was at the very beginning of time.

Logically, if time flows forward in the direction of entropy increase (the 2nd Law, or on a more fundamental basis the 0th Law, I guess), then if entropy decreases (the energy is gathering back as a singularity), time must be flowing backwards. Therefore, everything that has ever happened in the universe, including me typing out this reply, will happen again -- only backwards. Interesting, no?

But on a philisophical note -- if a system is in a state of disorder to the point that every particle in the system is equally in disorder, is that order? In which case, will time continue to flow forward (since entropy naturally increases)? How could the universe as a system become more disordered if every part of the system is already in equal disorder? Is the system, at that point, in a simultaneous state of order and disorder? Does time move sideways at that point? (I was making a funny, haha.)

0.o

 

[Soccerman06]

Heres another thought for you, if time freezes how can you see? Everything stops moving, electrons stop jumping from their current orbits, no photons are emitted, and no light is produced. So you couldnt see anything at all. Or is my theory just nonsense.

Edit: this assumes you stand perfectly still and dont move, so that you dont intercept photons in the way.

 

[AZReDWiNG]

Originally posted by: Soccerman06
Heres another thought for you, if time freezes how can you see? Everything stops moving, electrons stop jumping from their current orbits, no photons are emitted, and no light is produced. So you couldnt see anything at all. Or is my theory just nonsense.

Edit: this assumes you stand perfectly still and dont move, so that you dont intercept photons in the way.

If time freezes, how would you know you could not see?

There's the hole in that argument.



EDIT: In all seriousness, it takes work (aka energy) to create a thought, or even to fire a neural impulse. Therefore, if time could "freeze" in the sense that everything has stopped (which it can't unless entropy gets as far as I mentioned, in which case it would instantaneously start moving backwards anyways), you wouldn't be able to appreciate the fact that you can't see anyways.

 

[Soccerman06]

Originally posted by: AZReDWiNG

Originally posted by: Soccerman06
Heres another thought for you, if time freezes how can you see? Everything stops moving, electrons stop jumping from their current orbits, no photons are emitted, and no light is produced. So you couldnt see anything at all. Or is my theory just nonsense.

Edit: this assumes you stand perfectly still and dont move, so that you dont intercept photons in the way.

If time freezes, how would you know you could not see?

There's the hole in that argument.



EDIT: In all seriousness, it takes work (aka energy) to create a thought, or even to fire a neural impulse. Therefore, if time could "freeze" in the sense that everything has stopped (which it can't unless entropy gets as far as I mentioned, in which case it would instantaneously start moving backwards anyways), you wouldn't be able to appreciate the fact that you can't see anyways.

Ok lets assume that this is like time freezing like it does in STNG (any of the numerous times), how all time seems to stop except for one or a few people, if they just stood still, could they see anything or would it appear to be black.

 

[AZReDWiNG]

By STNG you mean Super Teenage Ninja Turtles? Teehee

If time suddenly stopped, everything would be frozen in its last state. You can see things only because the light (as a wave, not a particle -- but it probably doesn't make a difference) is absorbed by the surfaces it bounces off of (Snell's Law). The different frequencies at which the light is at after it is absorbed by the surface determines the color. If time stopped, everything would be at the same frequency it was before it stopped.

However, you could not be able to see it. The light never reaches your eyes. Obviously, if light doesn't reach your eyes, you can't see. If you started moving (and bumping the photons) you may get a picture for an instant, but no more.

 

[Stonejaw]

Well if by meaning that it reaches absolute zero then well I guess it does but you or whatever is in this stopage of time will not feel the effects of freezing because you do not have the time to freeze hehe sorry for the pun. Also because as soon as time resumes, assuming it does, you will actually have been at absolute zero (frozen) for a total time of zero anyways Hehe

 

[Netopia]

I?m not physicist, but isn?t time now simply considered a dimension? As such, isn?t it considered relative and not absolute? My point is, to me the question is sort of like asking ?what would happen if you stopped yellow?? or ?what if we could make vertical freeze??. Yellow as relative to WHAT? Vertical from WHOSE perspective? These are things that IIRC are not absolute, so you can?t talk about them being in an absolute state.

As to the professor that spoke about the universe ultimately ending in a new singularity, hasn?t recent evidence shown that the universe is accelerating at an ever increasing rate and not only won?t recollapse, but will eventually be so big that even light won?t be able to travel from star system to another because distances will be so great? Sort of sad, huh?

Joe

 

[AZReDWiNG]

Originally posted by: Netopia
I?m not physicist, but isn?t time now simply considered a dimension? As such, isn?t it considered relative and not absolute? My point is, to me the question is sort of like asking ?what would happen if you stopped yellow?? or ?what if we could make vertical freeze??. Yellow as relative to WHAT? Vertical from WHOSE perspective? These are things that IIRC are not absolute, so you can?t talk about them being in an absolute state.

Yellow IS absolute. The color yellow is the frequency at which light is emitted after bouncing off a particular surface. That's a moot point, though, I guess. "Vertical" is a relative perspective, yes, but if you change your axes of reference (for instance, if you're making a force diagram of a block moving down an incline, you'd rotate your X-Y plane by theta degrees), the relationship between the axes stays the same. They're still 90 degrees apart. So, while "vertical" is not absolute, the relationship between "vertical" and "horizontal" is.

Time is considered a dimension, yes, but unlike the other three dimensions, you can only move forward in time (towards entropy increase). It's not treated as the other three are. You don't measure movement forward/back, left/right, or up/down in terms of entropy increase, but time depends on entropy increase.

As to the professor that spoke about the universe ultimately ending in a new singularity, hasn?t recent evidence shown that the universe is accelerating at an ever increasing rate and not only won?t recollapse, but will eventually be so big that even light won?t be able to travel from star system to another because distances will be so great? Sort of sad, huh?

Joe

That's actually an AP Physics teacher (with a Ph.D in physics, so i guess he may as well be a professor -- whatever). In any case, every particle has SOME gravitational potential energy relative to other particles, unless you're an infinite distance away from something (which is for all intents and purposes impossible). EVENTUALLY, the particles will gravitate towards each other. It's all hypotheses. We can never know. My take on it: energy in the universe must be conserved. The universe can't just keep expanding without expending energy -- it's doing work to expand. If it is constantly expanding faster and faster, where is it getting that energy to do that work?

 

[silverpig]

Originally posted by: AZReDWiNGIn any case, every particle has SOME gravitational potential energy relative to other particles, unless you're an infinite distance away from something (which is for all intents and purposes impossible). EVENTUALLY, the particles will gravitate towards each other. It's all hypotheses. We can never know. My take on it: energy in the universe must be conserved. The universe can't just keep expanding without expending energy -- it's doing work to expand. If it is constantly expanding faster and faster, where is it getting that energy to do that work?

No, that's not the way it works. The universe is accelerating outwards as though there was an anti-gravity force. It beats gravity.

It's getting the energy from the same place that gravity gets its energy to pull stuff together...

 

[silverpig]

double post

 

[DrPizza]

Here: escape velocity
Yes, there would always be a force of attraction. But, as the object is moving away, the force is decreasing.
Yes, the force of attraction never reaches zero... but that doesn't necessarily mean the velocity will ever reach zero either.

If you google for a couple more links, I'm sure one will explain it well enough for you to get a good grasp of that concept. Quite honestly, a lot of people's intuition (coupled with knowledge) is one of the reasons it's hard to grasp.