# Re: starship-design: Re: FTL travel

```> From owner-starship-design@lists.uoregon.edu Mon Feb 21 03:27:08 2000
> From: STAR1SHIP@aol.com
>
> >  stevev@efn.org writes:
> >
> >  We honestly can't say whether
> >  FTL is possible or not, because no one has ever demonstrated it
> >  experimentally.  Until it's been proven possible and the engineering
> >  properties of an FTL drive can be determined, there's just no way to
> >  build it into a ship.
>
[...]
> I used the Newtonian equation correctly for the 1 g acceleration
> was relative to the star ship and not an earth observer requiring
> the equation you have in  mind. The relativistic equation you have
> in mind gives the relativistic velocity wrt earth observer.
> That is the wrong equation for the frame of  reference I use.
> Should you wish to use only the relativistic equations of
> time dilation for faster than light than use v=d/t,
> velocity = distance/time and calculate that relative to earth
> coasting at very near light speed, time  dilates to a point where
> to coast 4 light years requires two years ship giving twice light speed.
>
It seems there is some misunderstanding.
Tom receives "FTL" by dividing the distance in the Earth reference frame
by the time in the starship reference frame. For relativistic speeds,
due to time dilation, one indeed obtains from this division
a "velocity" larger than c. However, this is not a velocity
in physical sense - for which one should measure time and distance
in _the same_ reference frame.

Concerning the energy calculations, the energy (& mass ratios)
needed for obtaining relativistic speeds were calculated many
times before by physicists of far greater stature then we here,
and I have no reason to doubt their results, which are roughhly
the same as given by Steve in his post.
Hence, I suspect Tom obtains his optimistic results by similar
kind of juggling with equations and reference frames as with his "FTL"...

-- Zenon Kulpa
```