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Time in a box

  1. Aug 18, 2007 #1
    First post here...

    It seems to me (I have not read this anywhere, so forgive me if it sounds ignorant), that in a closed system, the measure of the quality we call "time" can only exist if there is a change in the form of energy or movement of something physical. For example, if I have a cube that contains 24 billiard balls with varying amounts of space between them, and we close the box so that the system is closed to the outside, then if there is no change inside the box (and I mean this to say that the billiard balls are absolutely stationary and are the smallest constituent particles that exist for this mind exercise), then there is no measurable change whether the box is opened 1 minute from now (by an outside observer) or 1 year from now, so there has been no passage of time inside that system.

    Now, lets change this by adding a conscious observer to the inside of the box with the same parameters as before. But he must follow the same rules as the billiard balls. His quantum state is absolutely static the moment we shut the lid on the box. He may promise that he will be able to notice and "feel" the passage of time, but I surmise that once the top is indeed closed, and everything inside the box becomes absolutely static until the top is opened, then our observer will not know, at all, whether we open the top 1 minute , 1 year or 1 decade from now.

    Obviously, this is just a mind game, as we cannot construct this experiment. But in your opinion, does it theoretically hold water?

    And by extrapolation, if the universe was/is a closed system, and everything inside it were "frozen" absolutely, nothing moved, no energy exchanged, and allowed to remain like this for a very long time, say a thousand years, and then, poof, things were allowed to continue instantly, would anybody be able to prove what just took place?

    Thanks for the opinions!!!

    I look forward to learning
  2. jcsd
  3. Aug 18, 2007 #2


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    This seems like an entirely philosophical question to me, so I'm moving it to the philosophy forum.

    It's a philosophical question and not a scientific one because I don't think it can be tested, even in principle. Another big clue that this is philosophical is that it is concerned with "existence".

    On a philosophical level, I don't understand why you think consciousness can exist in such a hypothetical box while you believe that time can not exist.

    If for example we assume that time is what we measure with a clock, and clocks are not possible within the box, then in some philosophical sense time isn't possible within the box either. So one might say "time does not exist". But is consciousness possible in this box? I don't see how. And if you come up with some way for consciousness to exist, it seems to me that whatever argument you use will probably imply that time "exists" as well.
  4. Aug 18, 2007 #3
    Apologies for putting it in the wrong forum. I am a very interested but equally uneducated fan of physics (and apparently philosophy!), but I understand your point.

    However, I suppose now that you mention it, I was assuming that consciousness would not exist without movement and energy changes. That if a quantum states were unchanged then consciousness would be suspended as well, which is why I supposed that the observer would literally "frozen" in time with no knowledge.
  5. Aug 22, 2007 #4
    C'mon, I may be new here but nobody has any opinion on the answer to this and it's far reaching implications?
  6. Aug 22, 2007 #5


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    You can't use a picture of a car as evidence that airplanes don't exist. Presenting a system that does not change with time does not at all imply that time does not exist.
    Well, if you seal the box and provide him with no food, water, or change of air, he'll die, so in that sense he'll sorta become static. Otherwise, no. The observer will observe the passage of time. And when he gets out of the box, it'll be all over his face (unless you provided him with a razor and shaving cream).
    You could, of course, prove that nothing took place. Again, that has nothing at all to do with whether time stopped.
  7. Aug 22, 2007 #6


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    How, exactly, would you seal this box 'time-tight'?

    I'm sorry if this sounds harsh, but what you are saying makes no logical sense at all.
  8. Aug 22, 2007 #7
    What I was getting at was that when I was reading all around about what, exactly, time is, there seems to be no clear answer. Add Einstein to the equation that there is no absolute time, and that makes it even more vexing.

    So I thought, well we measure time in some form or fashion by looking at change, where it is physical or electromagnetic or whatever. But something has to change.

    So I wondered, well, if nothing, and I mean absolutely nothing, including quantum states, changes, then how could you prove that time passed? But obviously, it would only work in a closed system. If you had an observer that was outside of the system, they would still have changes, and hence time.

    I know you cannot make a person stop changing, or anything stop in the quantum state. Maybe I went to far instead of getting back to the basic question about what is time.

    As far as the remark about the guy in the box starving, well you missed my point. I was saying that if EVERYTHING in the box, including him and all of his quantum states were frozen, then how would he know how long he had been "frozen". He wouldn't, at least inside the box. To him the process would be instantaneous, wouldn't it?

    And "if" everything in the universe were frozen, how would you know that time kept going? I thought time was a product of the universe? I could be wrong on that, I am just a layman on the subject. But if time is a component of the universe, doesn't that imply that it may not exist outside of it? I read that it was unrealistic to ask what happened before the big bang, because time is inside of it, just like space.

    Thanks for the discussion though.

    This is one of the most interesting web sites I have seen in a long time.
  9. Sep 1, 2007 #8
    Space - Time and (Motion of) Matter are related in a way that you cannot look upon one without using the other ones.

    Without matter - space has no meaning. Without motion - time has no meaning.
    Without matter - motion has no meaning.

    You can therefore not just look upon a universe with has matter and space, but no time.

    Considering the box:

    1. you may ask yourself the question - do they move? You can only tell by observing - but observation would interfere with the balls - and if not moving - possible start to move them.

    2. time is a property involving the entire universe - so in the box time has a meaning - simply because outside the box time has a meaning.
  10. Oct 18, 2007 #9
    Random comments

    If I may be so bold, I would like to comment and compare your thought experiment with another thought experiment. The one I am thinking of is where subject A is enclosed in a box that is experiencing a constant accelleration and subject B is an a box that is experiencing gravity. In two such closed systems there would be no way to differentiate which one you are experiencing because they are intrinsically equivallent.

    To make an analogy with my interpretation of your thought experiment, you are looking at the idea that if nothing was moving, with absolutely no changes in energy states whatsoever how would this differentiate with a system in which time simply did not exist? In my opinion I think that for all intensive puposes an observer in such a system where time did not exist and an observer in a system where all energy states were frozen as such in your example, it would be impossible to tell the difference.

    Simply put, it would be impossible to make a measurment within either system where no changes in energy states were made or no time existed. The fallacy of this thought experiment is that if it were impossible to make any such measurement in such a system, there is no way to determine if they really are the same. This is of course making the assumption that time could be non-existant in such a closed system and that it was possible for there to be absolutely no energy fluctuations or changes in a closed system.

    Even though we can not make any measurement in such systems we can look at the assumptions necessary to satisfy the existance such systems and from these we can determine these assumptions currently go against the knowledge we have so far about how the universe works.

    Although I found it a thought provoking and interesting thought experiment it unfortunatley doesn't yield any useful results.

    Just my two cents...
  11. Oct 21, 2007 #10
    Yes I agree upon you absolutely man. This is what our present knowledge in physics describes about time. My opinion says that this is the main problem with the modern physics that we regard the time in this way. We need some other entireley new concept to describe time even new than Einstein's concept of time that time is relative. I am devoting my days in order to search this sort of new concept nowdays. May I be success in near future
  12. Oct 21, 2007 #11


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    What is wrong with the way time works in modern physics? And works is the right word - it does work!
  13. Oct 23, 2007 #12
    Sure, it works. If it didn't there wouldn't be all that dynamics and thermodynamics and ballistics, etc.

    But it doesn't "exist", except as our "measurement" of change (motion) around us, which we attribute to "entropy" (the "flow" of energy). There is no easy way around "time" as a co-cepted "model" (by "co-cepted", I mean they are necessarily connected, you can't have one without the other, concepts we have).

    This seems to be a "big problem" for some people.
  14. Nov 16, 2007 #13
    I'm not sure why lack of movement would imply time was frozen, but the problem would not arise in a physical system. All systems have a "zero-point energy" - in a sense there is a minimum level of vibration which can never be zeroed out. So, even an apparently frozen system still "wiggles" a little at the quantum level. Nothing in nature ever stays perfectly still.
  15. Nov 19, 2007 #14
    First: I'm a journalist, so please excuse my physics!

    As I understand it, one of the "problems" of time is how to define it. I understand there still hasn't been found a way to describe time without using the word "time" or words that are based on the concept of time. In Einsteins general theory of relativity time is a part of spacetime and geometrically and mathematically works as a fourth dimension. But in everyday experience it doesn't seem to function completely as a "normal" dimension. Any road (dimension) can be travelled in both directions - time doesn't appear to work that way. Also if you travel at a certain speed on a road you get further than any other observer that travel at a slower speed. In time it is not like that. There is still a "now" any particle shares with all other particles no matter how fast you go through time. As if there is only one place to be in time - very contrary to our interaction with the three space dimensions. Finally there are the time-paradoxes that spring from the idea of time being something that you can travel backwards in. For instance that if it were ever possible to go back in time you should potentially be able to change a future which "allready" has occured. And also that you should expect to see "effect" before "cause" and other phenomenens that clearly are not part of our everyday life.

    Now I've been thinking about this - (pondering about the problems of physics is the best entertainment in the world!) and by accident I got this idea: I think time can be described as something we interact with as if accelerated in it in all directions at once. The argument is based on an analogy alas, but anyway it goes as follows:

    Now the equations of Lohrentz demonstrate that for a moving observer, distances in the the direction of travel is shortened and so is time relatively to the surroundings. For an accelerating object space becomes flatter and flatter and time shorter and shorter.

    Now I ask you to try and imagine a very strange particle which doesn't move in one direction as all other particles do. Instead this strange particle moves in all directions at once. That is indeed a strange particle I admit that - but anyway give it a chance! What happens if we accelerate this weird thing? I kick it hard. It gets heavier. But it doesn't change neither velocity nor direction. Of course not. It moves in all directions at once and that is equivalent to staying in a position. But if we observe the universe from the particle itself it is a different picture. Because it is accelerated the universe is shortened in the direction of movement - which is in all directions at once. So the more we kick the particle the smaller a universe does this particle exist in. And if we kick it so hard that it gets close to the velocity of light in all directions at once it becomes almost as large as the universe itself. (Something otherwise only stupid politicians experience in their own minds!) Now this is a very different description compared to how particles normally move. It contradicts the way any particle behaves in space. But notice, that it still allows for time to behave the way we conceive it. It doesn't contradict the behaviour of time. My point is that even though this description of a strange particle cannot be used on movement in space it fits our conception of movement in time just as well as the classical idea of a movement in one direction of one dimension. In other words we might just as well be moving in all directions in whatever time is. Now what does that prove? Nothing at all, I realize that. But there is more.

    There were also other differences in the behaviour of this strange particle. Our particle which was accelerated in all directions at once didn't move even though I kicked it hard. During acceleration and at highest "velocity" and even if slowed down again it stays at the same place. This means that if there are more of these strange particles around they all have to be at at the same place. They can never have moved away from each other regardless of acceleration or velocity. This seems exactly to fit the way time behaves. That even though time passes at differently in different frames of reference there is always a "now" that all particles in the universe share. Of course this description is only right if you can talk about "now" being equivalent to a position in time.

    But the best part of the argumentation remains I think: Because the greatest difference between the world of this strange particle and our world is the "direction" this funny thing has when sent off in all directions at once. Because if this particle should experience deviation (I know.. how would that happen?) or simply decide to turn around and run the other way (Yeah again.. But strange particles maybe behave strangely?..) then it would not change it's direction! It stays right on course in all directions at once. In the world of this particle there is no "right" or "left", no "back" or "forth", no "inwards" or "outwards". There is exactly one direction to travel in - namely all directions at once - no matter which way you turn your ship. Also this matches exactly the way time behaves.

    So if this description is right and time is something we relate to as accelerating in it in all directions at once then I think it solves many conceptual problems of time: Why we never see it go backwards or deviate. Why there is a commen "now" for all particles regardless of their age and regardless how quickly time passes for them. Why the direction of time always seems to be from now an onward. And also why the famous time paradoxes do not seem to be a part of our world.

    But it might mean that time is not a dimension. And it makes it possible that what we experience as time could be an interaction with an energy - an "ether" if you like. And if my understanding of the mathematics is right, I think it indicates that what works in the equations of Lohrentz is the relation between mass and rest mass rather than the velocity. (And that is maybe exactly the point of the general relativity?)

    I would love to hear your comments, please.
  16. Nov 19, 2007 #15
    My comment would be along the lines:
    Time as a dimension similar (or treated the same way) to distance is already an orthogonal relation we understand well. TIme, however, is not distance; but we assume that time 'has' a distance which is measurable in a similar way, by applying our concept of a regular, periodic motion of something to 'measure' it.

    Distance is measured with a regular, or static (stable) representative bit of length, and time is measured with a regular, periodic (harmonic) motion of something (that 'observes' time regularly). Before we invented an external way of doing this, we had only regular events (sunrise, etc) as a reference, and the regular 'ticking' going on inside each cell (especially the cells in our brain).

    But time and distance, though not the same thing, are features that emerge (simultaneously) from change (in the world). Change is 'explained' by entropy, another measurement we make of the difference in energy between one state and another. The observation of change is something all life must do necessarily, because if life stops changing, it stops happening (it dies).

    We, or any observer (any lifeform), cannot hope to step outside this reference (to change), because life is also change. Using an instrument, say, is just an extension of our observation, and isn't 'free' either (an instrument requires energy to 'work' and to exist in the first place -we perform work building an instrument which must therefore be part of any observing the instrument then does).

    We can measure time in terms of distance (of some journey, say), or we can measure distance in terms of time (how many days travel, say). But the two are kind of the same thing, in that sense -aspects of the same change (in entropy).
  17. Nov 20, 2007 #16
    Thanks for the comment. I really appreciate it! I hope to get more inputs as this "movement in all directions at once"- thing spends quite a lot of time in my head!

    I have some questions to your post: Because there is change there is time? Without any further relation for example that much change would imply "more" or "less" time? Or is that how it works in relativity? So that for example larger velocity can be regarded as more change? Or is the concept of time springing from change as a kind of nescessity - is that concept not at all connected to relativity? Would you not expect an underlying mechanism when for example a gravitational field changes the stream of time for an observer in the field compared with other observers in stronger og weaker fields? Some kind of mechanism time is part of instead of it simply being something that is there out of nescessity?
  18. Nov 22, 2007 #17
    I'll assume you're addressing my last post, so here goes:
    This observation is something that 'observers' do, it isn't logical to assume that the universe 'needs' anything, because we weren't around for quite some, well, 'time' (or amount of change, if you will).

    Observers have a 'need' for time --they need to keep track of events in an ordered way, and a periodic sampling and storing is how this is achieved.
    More or less change is another 'observation', and can be independent of time --lots of change, say a fire or earthquake, can happen in a short interval, or little change (say in a desert) for a much longer interval. But we (or other observers: 'lifeforms') are responsible for deciding this. The world is and does whatever it is or must --we only ever see a very small sample of all the change that occurs in our own experience and learning, or our lifetime.

    Using a measurement like time is a convenience. It's perfectly logical to use it like a real thing (we use measurements like this a lot), except it's a number. If Time was a real thing, we would need to collect it and store it (say in clocks), and replace it when it got 'used up', like petrol or fuel of some kind. A number is 'real' to us in the sense it is orthogonal to some change we 'notice', or 'see', or measure.
    Last edited: Nov 22, 2007
  19. Nov 22, 2007 #18
  20. Nov 22, 2007 #19
    Don't you mean time appears to be part of physical reality? If it's something with a real physical extent (volume) then where is it?
    Surely also you mean that the observation of radioactive decay is dependent on time (or on change), not the decay itself (which is "undefined" time-wise)?
    Last edited: Nov 22, 2007
  21. Nov 22, 2007 #20
    Yes I do mean that it must be a physical reality. But you're right! I have no idea where it is... But isn't the same situation with gravity. Where is that graviton we would like to find? We can calculate where it should be if it existed but not catch it! Is that so different from our problems with finding time?

    But this is exactly the eason why I think it is interesting that time can be described as something we accelerate in in all directions at once. Because that would maybe be a clue to what/where it is. But I realise my post has no mathematics in it and is based on analogies.

    Yes you're right. That must be what I meant. decay is dependant of time. But the physical reality of half-life is defined with the use of time, isn't it. And that should maybe be my argument.

    Last edited: Nov 23, 2007
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