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Never the twain shall meet.

  1. Jan 3, 2004 #1
    I just had a slight epiphany (nothing profound, just possibly interesting), with regard to the nature of past and future: They are just like East and West.

    Where, exactly, do East and West meet? Well, not quite never, as Kipling said, but very nearly so. You see, East and West, independent of a conscious observer do not ever meet. However, if there is a sentient being standing anywhere on Earth, they are (in their own opinion) the point where East and West meet. They can lift one arm and point toward West, and lift the other arm to point to East.

    It seems that it is almost exactly the same with the past and the future. The present is the illusion, produced by a person standing at any point in time, who can look forward to the future, and look back on the past. There is never a point where future and past meet (unless there is a minimal point of spacetime, in which case East and West would technically meet also, but at an unthinkably huge amount of points), but there is the so-called "specious present", which is the illusion that they do.

    Just a thought I thought I'd share.
  2. jcsd
  3. Jan 3, 2004 #2


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    I think you are talking about relative entities in absolute terms. Past and future are only defined insofar as they stand in a certain relation to what is called the present by an observor.

    If the present is an illusion, then so are past and future, since they are meaningless terms without reference to a specific "present." If you get rid of the present, you can't even speak of discrete entities known as the past and future which are to meet or not meet at some point. Likewise for East and West; without a certain geographical reference point, it is meaningless to ask where East and West meet, since the terms "East" and "West" themselves are meaningless (undefined) in the absence of such a reference point.
  4. Jan 4, 2004 #3
    I agree.

    I don't think that's what Mentat was implying though. Since that given person is observing the "present" he would never observe or misapprehend the past or future in the first place because he was never there to being with. So he would only illusevly appear to be defining the past and future, but he was or wouldn't define the two absolutes to start with, only illusionistically.

    I agree there, though.
  5. Jan 4, 2004 #4
    Re: never the twain shall meet

    Hi Mentat,
    I think that you are simply acknowledging two things: the existence of spacetime and the centrality of the observer. What you regard as an epiphany is perhaps the independent realization that (1) time is as much a dimension as space, and (2) positions within a coordinate sytem are (by definition) relative to some reference frame, and often there is an observer implicit in that frame.

    Thus, in our familiar four dimensional spacetime, this notion could be equally applicable to:

    1) East and West
    2) Above and Below
    3) In Front Of and Behind
    4) Past and Future

    What I find most interesting in a philosophical sense -- relating to the Platonic argument, anthropic principle, ontological interpretation of quantum theory, etc. -- is that without the observer, none of these terms have any meaning.

  6. Jan 5, 2004 #5
    Re: Re: never the twain shall meet

    How is the anthropic principle related to quantum theory?
  7. Jan 5, 2004 #6
    Yeah. I was thinking more of the fact that a human is spread accross spacetime...thus, since s/he is not a "point", s/he is not actually where East and West (or the past and the future) meet. Do you see what I'm getting at?
  8. Jan 5, 2004 #7
    You asked: "How is the anthropic principle related to quantum theory?"

    As I said, the *centrality of the observer* is a fundamental premise common to the anthropic principle, the Platonic argument and the ontological interpretation of quantum theory (whether that be the standard formalism of the Copenhagen interpretation, the Bohmian view or -- to a much lesser extent -- Everett's MWI).

    In the anthropic principle (both strong and weak versions) the centrality of the observer is implicit in the 'participatory' element of the principle. If the universe were not precisely as it is (ie. if Boltzmann's constant, Planck's constant, the gravitational constant, the cosmological constant, the strong and weak force constants, the rest masses of each particle, the speed of light, etc. were not precisely as they are), and if the universe were only slightly different than how it actually is, then we would simply not be here.

    Related to this notion is the idea that since we are comprised of atoms that are the remnants of previous supernovae (ie. the atoms C, H, N, O, P and S), then we are literally 'born of stardust', and as such we are a part of the universe that has the capability of self-awareness. In other words, we (i.e. sentient, conscious beings) are the way in which the universe is able to *know itself*. In this sense, the universe is meaningless without *knowers*, *experiencers* and *observers*.

    With regards to quantum theory, both the Copenhagen and Bohmian models posit that a particle exists in all possible states (*superposition*) when not being measured. Once the observer makes a measurement the superposition of this wave function *collapses* into one state.
    Again, the notion of the *observer's centrality* is fundamental to any ontological interpretation of QM.

    Understand that I am not in any way equating the anthropic principle with quantum theory. What I said was *only* that the observer's role is central to both of these ideas.

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