Yeah... generally speaking, putting FTL ships in a diagram that is designed with assumptions that you can't go FTL leads to paradoxical situations... But there is an interesting interpretation I had a bit earlier that is surprisingly self consistent and provides an explanation for why you wouldn't end up continuously creating mass or having unbounded copies of FTL objects flying around.
Posting here will either cement or kill my chances to get in the history books of relativistic physics...
Consider three waypoints (starts, whatever) spaced 4 light years apart. I'll keep the trend going of calling them A,B,C. An FTL ship starts at A, then goes to B at 2c, waits a year, goes to C at 2c, waits a year, then returns to A at 2c. Check out the following...
ref obs A
p ---------- ----------
A 0 v0 ^10 v0 ^10!
1
2 v1 ^9 v3 ^11
3
B 4 v2|v3 ^8 v6|v7 ^12
5
6 v4 ^7 v10 ^13
7
C 8 v5 ^6 v13 ^14
So what we have there in the P column is "distance from station A". The v and carat indicate direction of motion of an object at that position, and the number by it is the time the object is observed at that location by the given observer. The reference observer shows that the FTL ship leaves A, stops at B, goes to C, then leaves and returns to A.
From the standpoint of A, we see something odd. We see a ship heading from B to C at time 10, AND we see a ship materialize back at A at time 10! But the observer at A never saw a ship approach -
it had to have simply materialized. Furthermore, we also see that a "ship" appears to travel backwards to C starting at time 10 - its position gets farther away from A as time increases.
The interpretation I have is this: At time 10, an observer at A sees
a ship - antiship pair spontaneously materialize. Think about it like pair production. The "conventional" part of the pair remains at A - this is the ship that arrived back at A from the standpoint of the people on the ship. The "antiship" travels backwards to C - where it happens to arrive just as an observer at C sees the "original" conventional ship ready to depart. The ship and antiship appear to the observer at A to annihilate at time 14. What's really notable - the time of apparent annihilation at time 14 for observer A is the same "time" that, if a ship were to have departed C at time 6, an observer at A would no longer be able to detect a ship at C. It is a wholly consistent interpretation, even if I can't say what mechanism would cause it.
This has several interesting aspects. One important one : because the ship is an "antiship" there is no loss of conservation of mass or charge - when the observer at A sees the pair produced spontaneously, there is still a total of one net ship in the universe (in this case, two ships and one antiship). Also, an observer at A cannot "retain" multiple copies of a ship - it can only have one, which is an interesting way to address the "passengers on the ship can't feel like they are in two places at once" paradox.
I actually worked out the same diagram for observers at B and C - and they are actually all consistent. B and C are interesting though, because each of them see two ship-antiship productions and two annihilations. It's super late here right now though, but if there is interest I can post those cases tomorrow.
One fun side effect: What this interpretation suggests is that a ship approaching at FTL should appear and then have a blur shoot off into the distance. This is backwards from typical renderings of a ship "zooming in" from a point. But it makes sense - if a ship is FTL, it's going to arrive before any "blur" could have arrived.... the blur has to go backwards as the light from previous positions catches up to the ship!
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Topic: Science Thread (and !!SCIENCE!! Thread!) (Read 90704 times)