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Where would we be without the structure of time?

  1. Jun 20, 2003 #1


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    Time is everything to us, it structures all we do. Perhaps time is our true "god"? My question is, where would life be without the structure of time? The consistency of days, rotations around the sun, the phases of the moon etc...
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  3. Jun 21, 2003 #2
    Probably in some other dimension, beyond the earthly "physical" plane.
  4. Jun 21, 2003 #3
    I don't view time as an object or substance. I just think about how material is arranged one way, and then it is arranged another. I don't know what gives rise to the material interactions that allow us to perceive time.

    I think that time could "speed up", and we wouldn't notice, because our perception of time is dependent on the rate of physical interactions that would speed up, so everything would stay in proportion.

    I think that not having time is the same as not having change. From this would follow that there would be no life, because life is a system of interaction. My consciousness is none other than matter/energy moving around in my skull. If this interaction stopped, I would cease to be.

    As far as how would the absence of regular cycles affect life, well that is a question that, I think, leaves a wild range of speculation. Obviously, life on Earth has evolved in the presence of certain cycles, and a sudden lack of these cycles would be disastrous...I would even dare say apocalyptic.

    Could life have evovled without regular and frequent cycles? I think that, at least on a microscopic scale, yes. Aren't there, after all, microorganisms that live hidden away in places mostly unaffected by the cycles of day and year? Actually, even animals and plants (if they exist down there) live on the bottoms of the oceans, where I don't think the cycles that you and I are used to have much sway.
    I think that it obvious that life would be very different with different or no cycles.
  5. Jun 21, 2003 #4
    But what is time compared to Eternity? That which always was and that which always will be? The moment is Eternal and Ever-Present. Yet isn't it possible -- as Existentialists claim I believe -- to "live" within the moment?

    Hey don't mind me, I probably have no means by which to elaborate on it anyway ... it's just a thought in passing.
  6. Jun 21, 2003 #5
    Why so cautious? Time is everything not only to us, but to anything. Time is fundamental ingredient of Existence. Without it, there would be no interaction, no motion, no measure, no space, no energy, let alone life.

    For duration of planck time uncertainty energy conservation can be broken and you can extract energy from nothing, space. Interesting, isn't it - energy is function of space and time. Or maybe time alone?
  7. Jun 21, 2003 #6


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    That's a philosophical question...
    I have no idea. :wink:
  8. Jun 21, 2003 #7


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    I wouldn't go that far. I can easily concieve of a universe where only some timeless, flat Euclidean space exists. Of course in our universe, space and time are inseperable. It doesn't mean time creates space. In fact, one could just as equally claim that without space, time would have no existence.
  9. Jun 21, 2003 #8
    And yet if we had the ability to transport our essence/being/mind at will, from one end of the universe to next, then there would be no notion of time, just the experience of "being." Actually we already have this ability, we just don't know it.
  10. Jun 21, 2003 #9
    Consider for a moment the following:

    A signal is transmitted from point A to point B. A and B are separated by a finite distance. Consider three periods of time:

    1) The signal is launched from A.
    2) The signal resides in the space between A and B.
    3) The signal arrives at B.

    If (3) occurs simultaneously with (1) we say that the signal has traveled at infinite velocity. The signal has never resided in the intervening space and therefore there exists no space between A and B. A is virtually at the same point in space as B. For real space to exist between A and B it is necessary that a signal travelling between them be "lost" with reference to both points for a finite period of time.

    For real space to exist between two points a signal travelling between them will propagate at a finite velocity. If a signal will not travel between two points, as in the case when v=0, then we can also conclude that there is no link or intervening space between them. We have no means of detecting either an infinite velocity-supporting space or zero-velocity space, so they do not exist as usable concepts. If space cannot accommodate a signal it has no function and no reality. We are left then with the only real space, the home of the real and virtual vacuum. Space which supports a finite, nonzero velocity.

    I think of implications. Finite velocity of interaction is necessary. That means that arbitrary distance to be detectable must be covered in finite time. Thus, there must exist finite minimum meaningful (subplanck?) time unit, distance unit. Velocity isn't basic concept, its ratio of distance to time. Thus ratio of space to time is what causes holy velocity c, not either separately. Actual value of fundamental units of distance and time is arbitrary and irrelevant, its their ratio that counts. If either changes in local frame, it won't be necessarily detectable. We think c is constant. Then, any change in either unit would be detectable as distortion of space geometry. Time creates space for measuring observer.

    Time is the only means by which you can differentiate physical space (euclidean or else), without it you can't have notion of motion over distance. Space can't create time, for time is essence of change, and static timeless space has no capacity to change. Therefore time seems more fundamental to me.
    I guess geometry of actual space may be arbitrary, we have no means to detect other than rules of motion and interaction within given space. Like pixels in 3D game can't possibly know their physical location in computer memory, but only rules they obey. Aswell as pixels can't possibly know the real rate of their change and are thus constrained to their virtual time only, we also can't ever know about absolute time, but only our perceived time. Yet, time is unique in that virtual time can't exist without absolute time either.

    Imo, space and time are inseparable in any universe. As soon as dynamics of change and interaction exists, its basically time and instantly creates some sort of space.

    ps. experience of "being" IS to do with notion of time..
  11. Jun 21, 2003 #10


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    How can you have change without "something" that can change first? Think about it. In the real world, what is time but an evolving gravitational field? Classically speaking, of course.

    The flat Euclidean universe I mentioned, would be a place where nothing at all happens. Likewise, I can take the concept of time, and replace it with an extra spatial dimension, and still have a universe. There would be no change, but a static 4D space. So I don't see how change could possibly be more fundemental than space.
  12. Jun 21, 2003 #11
    an epistemological problem:

    how can anyone know that NO change occurs except that some kind of clock runs and the situation remains the same whenever it is checked.

    D.C. Where would we be without the structure of time?
    nowhere, I guess! Or would 'nowhen' be more apt?
  13. Jun 22, 2003 #12
    Yeah, its like 'how can you have energy without "something" that interacts to exchange energy'? What is 'evolving xxx field' without preassumption of concept of time? Without time it ought to be static. What is field, what is force without acceleration? How can acceleration of matter evolve, and then create concept of time? At some point fundamental enough it will get selfreferential anyway and has to be resolved with axioms.

    Suppose you have a line of points of space whose only property is reaction time to interaction. How can you distinguish them from spheres of finite size, with finite medium velocity? Finite time gives finite size to dimensionless points. Let the line be made of points with different reaction times, in sorted order. You have a field, where probability of interaction is higher towards points with faster reaction time, or you have preferred direction of interaction, explanation of tendency towards lowest potential. While if you depend on some constant velocity like c to perceive reality and make measurements, then size of points gets perceived larger towards points with 'faster' time. You have acceleration. But observer won't notice size dilation, instead, it will notice space curvature. Points with slow reaction time - inertia.

    Imagine that the points can exchange their properties. You have energy. Energy that has capacity to transform energy. With minimal set of mysterious ingredients - time. You have field, that creates curvature of space, basically gravity. You have inertia, thus mass. The only thing you need to let go is uniformity of local time, and you realise that theres nothing you can stick to as given, geometry, space or timeflow. You don't just think of relativistic time dilations, you think about QM level time fluctuations. And differences between matter, space, light and time slip away.

    It isn't comforting to imagine time that way. But it isn't easier to imagine any of modern hyper quantums like loops or strings or 12dimensions either.
    Really, you can't. You can shuffle around virtual time, but if you think about it, you'll see that you can't get away without true concept of time. If you imagine universe as a reel of 4D film, or 4th "spatial" dimension, then you still need to explain evolution of it, motion through that 4th dimension or whatnot. And you probably won't as a person accept view that universe is static fully predetermined 4D without any change or willed action possible in it, so why put that possibility on the table?
    People rarely think about such things, but there is no concept of closer vs further without concept of time.
  14. Jun 22, 2003 #13
    The Timer

    Without time we would be late.
    Um, no, I guess we would be obviously early.
    Wait a minute, there wouldn't be any early or late. And would we still move or would we be fixed in position like a painting, inanimate?
  15. Jun 22, 2003 #14
    flat euclidean universe

    If nothing moved, could there be spirits?
    When we think and dream no one sees any movement or time. There is alittle but not noticable. So if there are spirits, souls, or string-like things that are not usually noticed by us then maybe time doesn't matter to them.
    Is gravity needed for time? Maybe not, but if it is then we should ask if there is anything unaffected by gravity, like strings or light etc that may therefore be unaffected by time.
    Sorry, I think I did too many ifs.
    ONE more if, --- if gravity affects everything then something far out in space virtually untouched by gravity and naturally lightweight itself may be without time for a while. But then what would speed or acceleration have to do with it?
  16. Jun 22, 2003 #15


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    Exactly. That's why it would be absurd to think time is any more fundemental than space. Both are aspects of the same fundemental thing, the gravitational field.

    I can, because past present and future would then merely be different spatial locations in the 4D universe.

    That's the beauty of it, there is no evolution nor motion through it. Instead, all of time is just a single 4D existence. To quote Einstein: It appears therefore more natural to think of physical reality as a four dimensional existence, instead of, as hitherto, the evolution of a three dimensional existence."

    But that's just speculation. Still, it shows we can concieve of a universe without change, where everything would be mere geometry.

    That's why such a concept is somewhat unappealing. After all, time is as much part of our intution as space or anything else. But there is no reason time could not be a spatial dimension.
  17. Jun 22, 2003 #16


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    Re: flat euclidean universe

    From what I've read, no. Gravity is the curvature of space-time, but apparently it is possible to describe a flat universe (empty) where no gravity would exist. I don't know enough about GR to say for sure, but it seems that time is the evolution of the geometric relations that define the gravitational field.
    Last edited: Jun 22, 2003
  18. Jun 22, 2003 #17
    How about the concept of "intensity" or, the concept of "relativity," with respect to how closely things are related to each other (not in distance, but in likeness).
  19. Jun 26, 2003 #18
    Absurd? Why? Space isn't really something real, its percept of observation. Crumpled rope is still perfectly straight for a 1D creature living there. What makes space is relative distances measured by travel time.
    Gravitational field isn't fundamental, is it. Thus, both are not just aspects, but ingredients.

    you can't because you have no means to explain states of different 4D locations in terms of evolution. You are forced to accept creationism then. You can't explain our apparent movement along that 4th dimension and inability to turn back. Why don't we exist all simultaneously? What limits speed of c?

    I'm lost here. How can you conceive moving, living, evolving universe as static 4D geometry? We could probably conceive 4D 'picture' of universe that way, but not a 'movie show'.

    No, what you are doing is to equate virtual time to 4th spatial dimension. Its useful in modeling. You are superimposing infinite number of copies of 3D universes on line of 4th dimension just for sake of explaining time. Relativity of time would need even more. And then, after all that effort, there is still not a single reason why would there exist such monstrum in the order of perfectly sane evolution.

    There is damn simple reason why time can't be just spatial dimension: there is no way to explain a single change in this changing universe without a help of god.
  20. Jun 26, 2003 #19
    First off, Quantum Mechanics doesn't allow for "nothing to happen".

    Also, more importantly, the flat Euclidean universe that you mention would have to exist for some period of time, would it not?
  21. Jun 26, 2003 #20
    Actually, it oughtn't exist at all, without time. After all, for what duration of time would it be static, if there were no time? You cannot be static for zero time can you?

    You see, wimms, you have depended on the defining of time as though it were just the measurement of change - when, in fact, it is it's own dimension (according to Relativity), and exists regardless of whether anything actually occurs or not. Basically, changes occur over time, but time exists with or without them.

    It would be like saying that space is just the measurement of the distance between objects. According to Relativity, space is a set of dimensions, and exists regardless of whether there are objects to measure between or not.
  22. Jun 26, 2003 #21


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    So what? You still can't have time without first having the existence of something capable of change. In this universe, the geometric relations that define spacetime (the field) is that something.

    Change seems to a property of the field, and you can't have time without it.

    It has nothing to do with creationism. In a 4D timeless universe, past present and future exist in a static world. Nothing changes, because everything already exists.

    It could be argued that experience only has any meaning if it experience one 3D slice at a time. At any rate, I'm only trying to show that we can just as well conceive of timeless universe.

    There would be no moving or evolving in a timeless universe. It would just be an illusion due to our only being able to see it one 3D piece at a time.

    No, I'm just showing that it's something we can well imagine.

    Huh? That made no sense whatsoever.
    Last edited: Jun 26, 2003
  23. Jun 26, 2003 #22


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    Classically, no. But some have attempted to create a quantum version of a 4D timeless existence. Instead of having a 3D evolving wave function, they simply add the extra dimension and call it a timeless 4D wave function. I don't know how this idea actually relates to anything in the world of physics though.

    Last edited: Jun 26, 2003
  24. Jun 27, 2003 #23
    hi Mentat, good point. There are many more, but we can't flood them all together, or it would get too messy. Time is in so many concepts that its hard to ignore its fundamentality.

    please, I was promoting special importance of time. I don't define time as measurement of change, I'd rather think of it as of reason for change. Relativity doesn't deal with fundamentals, but with statistical cosmological scales. You put in purple your view, but what if Where there is no change, there is no perception of time? Besides, timeflow in SR is relative and depends on inertial frame velocity or mass. So its not very correct to say time exists independant from changes.

    You cannot exist for zero time can you?
    You cannot be static for zero time can you?
    You cannot change in zero time can you?
    You cannot detect time without change can you?

    see, minimal change of time is necessarily finite and nonzero.
    How do you define time between changes? Unless you have external reference, you don't. Thus, if you have two systems that go through given changes simultaneously:
    what is time for each system? They don't know. They can only take mutual reference as measure of time. Does it mean that time is a merely illusory product of change? At first it might seem so, but what was the reason why 1st system went through 6 states while 2nd only through 2 states? You might say that 2nd system was static during universal timeflow. and time dilation? Why does time flow differently?
    Is it that there is difference in energy density that 'somehow' changes timeflow, or is it difference in timeflow that can be directly expressed into energy fields? I know its unconventional, but I'm amused that its almost impossible to find ponderings in such direction.

    I know. We bow to Relativity in phys forums. Here we think relaxed. The set of dimensions you call space is put in place via constancy of velocity of light c. Its the measure of distance in cosmos, nothing else. Velocity depends on timeflow. Where c varies, Relativity fails, therefore it states that geometry of space varies, not c. it works.
    As I've understood, in QM its not so sure that space exists between objects unless you measure.
    But my point was different: not that space doesn't exist unless you measure, but that amount of it depends on how you measure. And that depends directly on time. Without time, lightyear and meter are equal. Its time that makes the difference. Thus, time allows you to differentiate space. Without it, there would be no space.
  25. Jun 27, 2003 #24
    If something as untouchable as 'geometric relations' is something, then I see no reason why one can't define quantums of spacetime whose properties depend on value of time. You could reach same eventual geometric relations of space, on the way explaining few fundamentals.

    Its chicken-egg problem anyway. You can't have geometric relations that change shape without concept of time, and you hardly can have concept of time without something that changes. Though, I'd ponder about time itself as the changing stuff.

    Correction: you can't detect time without change. You are insider, so you depend on the time 'to exist' yourself. Act of change itself cannot happen, if there already isn't concept of time. Difference between real time and virtual time.

    I'm amused why you stop at the exciting example. 3D 'shots' differ from each other by minute changes on that 4th dimension. However you try to run, they are called CHANGES. They stare at you every day. 4D static universe or not, the damn universe appeared from somewhere somehow. If its STATIC, then how the hell it appeared as it is? god, whatelse.

    How funny. Static 4D universe, and somehow we need to experience it 1 slice at a time in sequential order. I realise what you are trying, but I have tried, well before, and failed. I can't conceive 4D static universe without inherent concept of time. I think you only on surface believe you can. If you try honestly and hard enough, you'd find alot of problems.

    at a time. And what is IT that 'changes' the one 3D piece that we see next???
    And what a tremendous waste it is to have infinite amount of 3D copies of real universe just to offer illusion of time, instead of having one 3D universe and let it evolve.
    This makes me imagine chess: first you need to have zillions of boards, all populated by a unique setup of game states, and only then can you play, by looking at single copy of board state at a time, instead of just moving pieces.

    sorry. I thought its obvious that static 4D universe must come from somewhere somehow in such a way that it could offer illusion of evolution.
  26. Jun 28, 2003 #25

    Time can't be fundmental to reality. For time to be fundemental, it must exist everywhere. Yet time ceases at the speed of light.

    For those curious, an interesting book is "The End of Time" by Julian Barbour. His picture of a timeless reality is similiar to Eh's explanation.
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