OK...now I'm really confused. Wouldn't a faster than light transfer of information arrive before it was sent? That would imply to me that the information would go from the future into the past.
I meant to add that I will post a more detailed explanation to your question as well, as soon as I have the time.
Not precisely, if I understand it correctly (and I might not). It would appear to to someone observing the point of origin through light-waves, but to take my earlier example, while you might be observing the earth as it was 10 years ago from a point 10 light-years away, the earth isn't actually 10 years younger--that's just how long the light took to reach there. If you sent an ansible signal to earth, you wouldn't see an instant result--you'd have to wait ten years for the light waves carrying the result to reach you.
If I'm wrong, please someone explain how and why.
OK, here is the deal: I don't know what the deal is! To be more exact, the specific examples given here do not violate causality of their own accord but causality is violated nonetheless. Here, I'll explain.
This would be a lot easier if I could sketch it out as a visual, but I'll do the best I can (which isn't anything to get excited about..) First of all, in both instances - superluminal communication between 'stationary' locations or superluminal communication between locations moving apart at a 99% luminal velocity - we are only dealing with one inertial frame. Rather than think of temporal events along a unilinear progression, it is more apt to place them on a 'space-time' grid traversed by our two intrepid communicators.
Now, think of two parallel lines on that grid. The first line is earth and the second line is our starship moving away from earth at 99% luminal speed. Now, both lines begin on July 1 when our starship leaves the earth. As the starship bebops along into the great unknown, the effects of time dilation essentially begin to 'compress' time on the starship as observed from the earth's frame of reference.
OK, so now let's draw a line perpendicular to our two parallel lines. This line will represent our first superluminal communication. Now the point at which this line intersects Earth's temporal trajectory is July 4, but due to the time dilation effect, the intersection time on our starship is now July 3. OK, so our hysterical Earthling sends out her signal: "Terrible news! President Hillary Clinton assassinated! USA in mourning." Timestamp: 12:00 noon July 4. However, the time on your starship clock reads 12:00 noon July 3. You think to yourself, 'Oh, cool! I've already added a day to my life!' =)
Now, naturally, you send a signal back to Earth as swiftly as your trembling fingers can type: "Mourning?! Oh, please. Get a grip!" Now, let's draw another line across our grid perpendicular to our two parallel communicators to represent this subspace reply communique. As should be clear now, this does not create any causality problem. Indeed, Hillary-mourning Earth bimbo won't receive the message on her July 2; she's probably going to receive it on July 5 or 6!
The dreadful fallacy in that original post was precisely that: you fail to have NO privileged reference frames! Quite to the contrary, you alternate privileging one reference frame and then the other depending on who is transmitting a communication. Instead, our space-time grid represents the single inertial frame that encompasses both of our ansibles. It does not favor the reference frame of either. Instead, it represents the time dilation by progressively 'compressing' the movement of space-time at a given rate along the continuum of our starship as viewed from the vantage point of Earth.
You could accomplish the same effect by progressively 'elongating' the movement of space-time at a steady rate along the Earthling continuum as viewed from the starship's vantage point or by varying both rates as a steady function of one another. The relevant point being is that while our "instantaneous" superluminal communication does not in fact appear instantaneous to either as perceived by either vantage point, this is because the communique is itself exhibiting the perceptual time dilation effects instructed by special relativity.
It makes no difference if we instead conceptualize two ansibles on separate starships moving away from one another, because then we are merely replacing one inertial frame with another. The same is true if we are imagining two 'stationary' transmitters in separate star systems; they are operating along one inertial frame in relation to one another. The single inertial frame cannot twist in such a way as to make events in one locale's absolute future appear to be in that locale's past.
So, we've solved our causality problem, right? WRONG! As soon as another inertial frame is introduced - a third observer along a separate space-time 'trajectory' - *then* we've got the causality problems when they interact in tandem. So, basically what it comes down to is that we can only have one starship travelling at warp speed at any given moment - or else the universe collapses in a big crunch... =)
My solution is to declare that quantum mechanics is an incomplete theory. If that's good enough for Einstein it's more than good enough for me!!
Anyone should feel free to please correct any stupidity that crept into my post..