But Jump doesn’t take into account velocity within it. Velocity is only relative to the two places you jump from.
You don’t accelerate in Jump. And Jump take 7 days.
So in your example, you jump out (and arrive 7 days later) accelerate 100m/s towards the system you just jumped from (which will take some more time) then jump back (and arrive 7 days later) exiting at the same speed you accelerated to when you jumped.
Which means you arrive back in the system you left 14 days after you initially jumped. Not before. Because 2 jumps take 14 days.
That's why I say I can never work out how you do it; because at no point are you travelling back in time, even though jump is faster then the speed of light.
It takes a fixed time to jump. When you enter jump space you come out of it after you went in, you don't come out of it before.
-----Original Message-----
From: xxxxxx@simplelists.com <xxxxxx@simplelists.com> On Behalf Of Thomas Jones-Low
Sent: 07 September 2020 16:06
To: xxxxxx@simplelists.com
Subject: Re: [TML]A question for the panel regarding jump drive and relativity
On 9/7/2020 10:54 AM, xxxxxx@quibell.org.uk wrote:
> So the answer is of course; Yes. Because the ships travel faster than
> light they can time travel.
>
> However I’ve never been work out how …
>
As I recall working this out from a previous discussion, it requires two jumps, one out, then one back and moving at a relativistic velocity compared to the staring system. And by applying the Lorenz transformations on your apparent velocity (from jumping), the t variable quickly becomes negative. Which means you have traveled backwards through time.
So you jump out, accelerate to 100km/s* toward the system you just left, then jump again into the system to appear before you left.
* NOTE: Velocity is from a long ago memory from a spreadsheet now vanished down the memory hole.
But that's the general idea. You need to account for the velocity of the ship while in Jump as actual travel through space at 170c.
If you assume the Jump is more akin to a wormhole, where the ship is taking a shortcut, and not actually traveling the whole distance, I think you get some different results.
--
Thomas Jones-Low
Work: xxxxxx@softstart.com
Home: xxxxxx@gmail.com
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