JesseM said:
Not really, that whole "moving at the speed of light" notion is just a cute mathematical trick, it doesn't really make sense to interpret it as "motion" in a literal sense since it isn't change in something with respect to time. See [post=430613]this post[/post] for details.
Not really, JesseM. We may not be on the same page here. First, I am simply trying to represent a particular interpretation of Special Relativity (not my own) in which you first regard the universe as a 4-dimensional space with time as a parameter that provides a description of motion using parametric equations (just like you would do it for projectile motion in ordinary 3-space). So, now we have a 4-dimensional space populated by 4-dimensional static material objects. These objects typically are very small in X1, X2, and X3 but string out for millions or billions of miles along their worldline.
Consider the 4-D observer object shown in the sketch below. A 4-D photon extends out to a position of 186000 mi along X1 and 186000 mi along X4. Keep in mind that the 4-D objects are frozen into the "block universe" and do not move. For the sake of making progress with the concept we assume some "aspect" of the observer moves along the observers vertical worldline to get to the point at 186000 mi along X4. From the sketch it is obvious that "aspect" (consciousness, ..., whatever...) had to move at speed c (although we can easily bring in an illusion concept ala Godel, because otherwise you have a 3-D consciousness moving, and given simultainaeity issues of SR, that leads inevitably to zombies and Solipsm (Einstein insisted on avoiding a concept that would lead to Solipsism).
Now, this is definitely not a mathematical trick--it is strictly 4-D geometry. You are just operating on an interpretation of a 4-D universe populated with 4-D objects which is at least consistent with the situation described. I personally don't see that this is a proven concept--but it at least seems consistent with SR.
JesseM said:
The actual events in your brain (and consequent behaviors like talking) are exactly the same in the "block universe" picture as they are in the "flowing time" picture, so you should have the same thoughts and feelings either way, I don't see why it would make a difference.
I think I would agree with you. However, the "flowing time" should be given a sharper description. I take it that the "flowing time" still persists in conjunction with 4-D space populated by 4-D objects. Otherwise how is it that different observers can have the different cross-section "views" of the universe if there is not a 4-D space or 4-D objects for which cross-sections can be "viewed."
JesseM said:
edit: and to get more philosophical, even if you think of spacetime itself in the "block universe" picture, if you take the stance that subjective
qualia are not completely equivalent to physical brain states (even if they are completely
determined by them, as some philosophers like
David Chalmers believe), then if you're worried about the subjective sense of time you could always adopt a picture where there's a sort of subjective "spotlight" of consciousness moving in a sort of nonphysical "mental time" along the worldline of some brain, successively experiencing different brain states. Perhaps an advocate of the
many-minds interpretation of quantum mechanics might also be likely to take a view like this...
Of course you are right here. I think the subjective "spotlight" is essentially consistent with the Godel consciousness spanning the entire worldline, possibly even randomly focusing attention on various locations along the worldine. How would you know you hadn't already focused on a given spot on the worldline before--as you point out, the neuron information informs the consciousness with memories of past and the present state, etc. In the same way we experience our consciousness changing focus among the various parts of our brains (picturing food one moment, remembering some distant memory the next, etc.), the 4-D concousness can roam the entire worldline sampling sections of neurons evoking various illusions (I think this was the upshot of Godel's concept, but I could be very wrong here and someone might be able to give a more accurate representation of Godel). And I think Julian Barbour (and others) have implied that Einstein was thinking in terms of his departed Besso has getting along just fine--still living a good life along his earlier worldline (I appologize for this kind of remark without solid reference--but Einstein's letter has been discussed in a number of references that I don't have in front of me at the moment).
Then, we enter a whole new arena when Q.M. starts weighing in. It has been a while since I've read Chalmers, but it seems I came away feeling he had good rationale for his concepts but actually did not remove the 4-D objects but instead made them infinitely more complex.
Finally, to close the loop, all of this commentary is just to demonstrate that there is some major thinking that would fully support Passionflower's earlier comment about free will.
(I'm afraid we've outlived our metaphysical/philosophical license here--sorry)
