It seems a lot of the arguments here would be far more widely reaching than intended. Suppose we aren't concerned about three reference frames anymore, just the usual two. (In the following examples, the relative speed v=.866c - set to be such that gamma is two. Things contract to half their length.) The raptor is standing still on an 'x' on the ground. 100 feet away from that 'x' is a stationary wall. Some questions:
1. The raptor starts running towards the wall at velocity v. How far away should that wall be in the raptor's frame (and thus drawn on the screen)? (a) 100 feet away still, or (b) contracted to 50 feet?
Answering (a) would imply a Newtonian world. No length contraction, etc. Answering (b) would make sense to me, from a relativistic perspective. Length contraction in the direction of motion.
2. Barely after leaving the 'x', the raptor comes to a full stop. Where does the wall appear to be now? (a) 200 feet away, (b) 100 feet away
This is an easy one. Since the raptor (or equivalently the room) slowed down, length contraction will be undone. Things should double in length... so it will be at (b) 100 feet again.
3. The raptor is standing still on the 'x' again, and remains still. On the wall there is a cannon, aimed at the raptor. It fires a bullet directly towards our hero at speed v. Where should the bullet first appear in the raptor's frame? (a) 100 feet away, or (b) contracted to 50 feet away.
Many of you seem to be arguing for (a). After all the cannon is 100 feet away, so the bullet has to appear there. But there is a direct analogy between this and the first question. If the moving wall appears closer, the moving bullet should, too. So, again, the answer should be (b). If you're still not sure, let's add another part to the question:
4. There is a pane of bulletproof glass directly in front of the cannon. So, just moments after being launched (and traveling a negligible distance) the bullet stops again. The bullet, the glass, the raptor, and the cannon are all in the same reference frame. Where is the bullet now? (a) 200 feet away, (b) 100 feet away
So the bullet was in a contracted frame, and comes to rest in the raptor's and room's frame... In complete equivalence to question 2, we should expect the bullet to appear twice as far away as we answered for question 3. (a) is clearly absurd... there are no relativistic effects to think about with this question... so how could the pane of glass have stopped a bullet 100 feet away from it? (b) makes sense from not only an intuitive standpoint, but also when doubling our result from question 3.
And just to be entirely clear:
5. A T-Rex is standing still next to the cannon through all these experiments. Zero feet away from the cannon. Where would the bullet first appear to him?
Just as with question 3, we can length-contract the frame... 0/2 = 0... so the T-Rex sees the bullet in the same locale as the cannon. (This is why I think we're implying a local
observer any time we discuss two events happening at the same place and time.)
Qaanol wrote: ...photons from the bullet as it punctures paper target 2,048, will follow identical paths at the same speed, so they will reach the dinosaur simultaneously (according to all observers, though they may disagree on the specific time) from the same direction (according to all observers, though they may disagree on the specific direction) so the raptor will see the bullet and the target in the same location at the same time, for every single one of the paper targets filling the space along a straight line (in proper rest frame of targets) between the gun and the target.
You're argument seems to be that because of identical the photon paths, all observers will see
the events overlap. That isn't the case. Check out http://www.spacetimetravel.org/
to learn about the weird warpy world of seen relativity. They have good descriptions of how when we view a non-co-moving reference frame, it will bend and curve. A bending path of bullets wouldn't line up with a straight path no matter what one did. I think there are some Newtonian assumptions underlying your argument as it stands.