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Dependency on Time and Space

  1. Oct 1, 2009 #1

    I'm wondering why there is no space, when I take away the time.

    I imagine a two-dimensional room and a point in it, which is an object. If I take away the time, the object can't move or change anymore but the space is still there.

    To me space is just a room with objects in it (i think this is wrong).

    Whers is my logical error?
    Last edited: Oct 1, 2009
  2. jcsd
  3. Oct 1, 2009 #2


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    I don't know how to answer the question "what is my logical error" but I can approach this:

    It's hard to stipulate what a room with objects would be without time. But we can make some guesses...

    Firstly, photons wouldn't be constantly streaming from the objects without time (as electrons wouldn't be transitioning) so you wouldn't see anything without time (as the photons wouldn't be reaching your eye and giving you visual information)

    Secondly (in at least the Bohr model of the atom) the electron wouldn't circulate the nucleus, so I imagine the electromagnetic force that keeps you from falling through the floor wouldn't work (objects would lose solidity).

    Thirdly, the kinetic energy of particles that we measure as temperature/heat would no longer exist. There would be no energy at all anymore... (except for maybe potential).

    But these are all stipulations...
  4. Oct 1, 2009 #3


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    Hmm... you know... I haven't really answered your question. I've talked about stuff that depends on time, but not necessarily space.

    I would direct you to the Relativity forums in the physics section up above. I believe your answers would be more straightforward up there and more relevant.
  5. Oct 2, 2009 #4
    I liken space to a loom, if we could frame what we see with steel rods, which is relative. Time I see as the room, if you take the room away so goes the loom.
  6. Oct 2, 2009 #5
    Without time, you can't infer the existence of space and vice versa. The object in your room, in absence of movement or interaction, becomes part of the space, which in fact becomes a singularity of sorts, in absence of a greater frame of reference. In order to understand something rationally, you need to "cut" it in at least 2 parts, view it from at least two dimensions. Difference is the basis of reason.

    I recommend reading Flatland, Kant and maybe something on Taoism. There's wikibook on special relativity that does a great job at explaining things, too.
  7. Oct 2, 2009 #6
    Movement or interaction, do not appear to be the same to me, I can measure interaction but I can never measure all movement until it interacts. We measure a photon as one dimensional movement a point with duration, yet it needs two dimensions space/time. I can picture a photon as a line from the side but I can not detect it from the sides nor the back, only where it interacts head on. I do not measure the photons behind the first that are still in transit until they interact with me. I feel the same for the motion within every atom which is the flip side of this interaction we use as a detector.

    Thanks for the references.
  8. Oct 2, 2009 #7
    I think the interactions of waves is our shared present and I don't think it is beyond reason.
  9. Oct 2, 2009 #8
    I'm speaking purely in philosophical terms, not scientifically. By movement or interaction I simply mean change. Change implies difference. Without difference, there can be no reason.

    Here's another angle. Mathematics cannot exist with only one number. Along the same line, regarding the limits of reason, infinity is a good example. As a concept, it cannot be defined mathematically the same way you define a number, it is not something that can be understood rationally, but rather intuitively, holistically.

    I like the waves analogy, too, but I don't believe there's a finite number of them. As such, pure reason alone is insufficient in order to comprehend reality. Corny as it may sound, one has to feel the waves.
  10. Oct 4, 2009 #9


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    on philosophy and science:
    They go together like a horse and carriage. It's difficult to have meaningful philosophy if it doesn't pertain to reality (i.e. physical reality in this case... or physics...). It's also difficult to begin to discuss reality without fundamental assumptions and definitions (i.e. philosophy).

    on infinity:
    I actually needed numbers to make sense of infnity. I don't believe infinities exist in nature, but if we take a really small number and divide it by a really huge number, the number will be practically 0. That's the way I initially grasped 1/inf = 0 because there's really no such thing as inf so far.
  11. Oct 4, 2009 #10
    Well, philosophy is considered to be the mother of all sciences. I think that's a bit smug on behalf of modern philosophers, since the ancient ones were scientists just as much as philosophers, if not more.

    The thing is, science works with maths and numbers, which tend to divide more and more. Philosophy works with concepts and words, which tend to encompass more and more. They are indeed crucial to one another, but they shouldn't be mixed up. In other words, philosophical concepts shouldn't(couldn't?) be formulated mathematically and scientific proofs in unadulterated form shouldn't be used as the basis of philosophies. Otherwise you end up with quantum mysticism, for instance.

    Regarding infinity, as you can see the best mathematical description is "a really big number", and it's not quite accurate. The biggest and smallest numbers are still finite by definition and their ratio will be finite as well. Whether or not infinities exist, it couldn't ever be proven, mathematically, or by observation.

    My math teacher always stressed the fact that the infinity symbol is not a number and repeatedly gave me the same lecture whenever I forgot to put lim in front of expressions. So my first reaction to 1/inf=0 is to rewrite it as limit(x->inf) 1/x = 0 .
  12. Oct 4, 2009 #11


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    Yeah, that's unfortunate. I think this quantum mysticism crap often takes a certain kind of person that's not really willing to accept what's right under their nose. Of course, there are some tolerable aspects of mysticism, but we often use it with a negative connotation here, so many people do not understand what real mysticism is anymore.

    My math teachers would agree with yours. A lot of my physics teachers aren't so bothered by it. Often they avoid it all together by just saying "this is huge compared to this so we can just drop this term"
  13. Oct 5, 2009 #12
    But there is movement without interaction as in all the photons in transit that we as individuals haven't detected yet. Interactions are the changes, in the present while they happen that a clock counts. Photons are only detected in the present.

    Many worlds seems to fall into this, after all, in this world I live and in others I am already dead or as my mother said "I'm glad physics today is finally getting the point about the afterlife.".

    Like plancks units I think of infinite as relative, which is more in line with the limits of math, it is the zero that I can't imagine.
  14. Oct 6, 2009 #13
    At least that one came from scientists. There's worse stuff out there. Stuff like karmions, the karma particle.

    If you could, you'd probably attain enlightenment spontaneously. We're finite amounts of substance. Nothingness and infinity don't come naturally.
    Last edited: Oct 6, 2009
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