Time dimension extent of a 4-dimension object

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In three dimensions physical objects have an extent ( non-zero length ) along all three dimensions.

If it is accepted that the four dimensions of general relativity correspond to physical reality, does that imply that physical objects also have a non-zero ( non-infinitesimal ) extent along the time dimension?

If so, does an object exist, in part, in the future and the past?

If so, does if imply that a photon can "see ahead" enough to be behave appropriately in the two slit experiment?
 
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Good questions.
jpi said:
If it is accepted that the four dimensions of general relativity correspond to physical reality, does that imply that physical objects also have a non-zero ( non-infinitesimal ) extent along the time dimension?
It would help if you thought about this in terms of how we describe things: i.e. we describe an object by defining an extent in 3D space. Similarly, if we described a length of time to describe it, we would just be describing a duration. That's exactly what you're doing when you ask, "how long is the movie?" With a event it is relatively simple: 'such and such occurred for so long.' With an object it is a little strange, we don't necessarily know how long an object will exist, or how long it has existed.
It comes in handy in particle physics though.

jpi said:
If so, does an object exist, in part, in the future and the past?
That's more of a philosophical question---how you interpret these things... but yes, that's definitely accurate to some extent.

jpi said:
If so, does if imply that a photon can "see ahead" enough to be behave appropriately in the two slit experiment?
No. Not at all. Photons can't 'see' anything---because they don't have a valid reference frame. Additionally, even if they could 'see,' they would no equivalent of actions---because everything would appear to be at the same instant in time and space... sounds weird because it doesn't work--you can't think in the photons frame.
 
jpi said:
IIf so, does if imply that a photon can "see ahead" enough to be behave appropriately in the two slit experiment?

Photons are not alive, they don't "see" anything, and don't have a concept of appropriate behavior.
 
You might enjoy reading Cramer's "Transactional Interpretation of Quantum Mechanics" (TIQM). He proposes that events involve QM waves moving both forward & backwards in time simultaneously.

http://en.wikipedia.org/wiki/TIQM