Re: lawless physics (fwd)

[John Mallinckrodt <ajmallinckro@CSUPomona.Edu>]

On Tue, 17 Mar 1998, Richard W. Tarara wrote:

> I really don't understand your statement below.  No matter how fast I
> travel, I can't get to any other star system before my current 'NOW'.  Say I
> can travel at 10 times the speed of light as measured from earth and I head
> off for a star system 10 light-years away.  I can't get there before St.
> Pat's Day 1999 (earth time),  and assuming I could transmit a video signal
> back to earth (via 'subspace' at the same speed) it couldn't arrive before
> 3/17/2000.  How do pull off the 'time travel' scenario implied below?

Rick,

Perhaps the implications of my statement, "one person's 'faster 
than light' is another person's 'backward in time'," are not yet 
clear to you.

If someone on Earth determines that you are traveling at 10 c, 
someone else--moving in some very reasonable manner with a speed 
less than c wrt to Earth--will determine that you are traveling 
backward in time.  (Please consult the Lorentz transformation for 
details.)  Now, if you can travel backward in time relative to one 
observer, then, by the principle of relativity, you can do so 
relative to *any* observer.  So I am simply suggesting that you do 
so.  *Why* would you limit yourself to 10 c when you can just as 
easily travel backward in time?

John
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