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Questions Regarding Time

  1. Mar 1, 2009 #1
    I don't have a physics background so be as generous as you like in assuming my ignorance. I am studying philosophy and, currently, the idea of identity existing through time. I have an argument that suggests identity can't exist through time because time is a property of objects that changes, thus, making the objects no longer identical.

    To get a better understanding of my own argument, I need a better understanding of time. Time is a 4th dimension with respect to space. Can I treat time in a way similar to how I treat space. For instance, an object can't exist in two places at once because of spacial limitations. Can I assume time and space are attached in such a way as you could use coordinates to describe them (space x,y,z, at time "t")?'
  2. jcsd
  3. Mar 2, 2009 #2
    I'd say that spatial configurations are continually changing. Ponderable objects are bounded systems. The boundaries of some systems are more persistent than others.

    I think of time as referring to indexes of spatial configurations (or sets thereof). This is in keeping with its operational definition per SR and it's usage in ordinary language.
  4. Mar 2, 2009 #3


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    As I posted here, there are two ontological schools of thought here: perdurantism and endurantism. Perdurantism says that objects are unchanging and four-dimensional. Endurantism says that objects are three-dimensional and change through time.
  5. Mar 2, 2009 #4
    I'm definitely a presentist endurantist.

    Yes, the set of spatial (x,y,z) coordinates corresponding to the 3D shapes and relative positions of some set of objects is associated with a time (t) coordinate corresponding to a clock readout (the accumulated count of some regular periodic oscillator).
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