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Re: starship-design: FTL idea - Steve

Hello again Steve,

>You can't have another "rest" frame.  If you're going to declare a
>particular frame to be the "rest" frame, you need to work the problem
>consistently with reference to that.

I know this. What I wanted to suggest before was that in the frame of the
initiator of the FTL bullet, things don't go reverse.

So if other frames measure their relative velocity to the frame of the
initiator, they'll be able to explain the reversed order of events.

We see a bullet flying backside first from A to B. The space time coordinate
of the bullet leaving A is (0,0,0,0) and the coordinate of the bullet
reaching B is (3.900,4.818,0,0)
Measuring the relative velocity of A, it turns out to be moving towards you
with a velocity of 0.9c

Calculating what happened according to frame A:
A happened at (0,0,0,0) and at B(-1,3,0,0)

(The numbers are the reverse of the little task you gave me

They saw a bullet nose pointed forward coming from B, the opposite direction
of your measurement!
Of course this isn't surprising since spacelike coordinates may reverse the
ordering of events, but at least we know that those who could influence the
events didn't see any reversal of events.

Knowing this, I would conclude that in the frame of the initiator, FTL
cannot influence his past. Or in other words he cannot influence his past
using FTL.