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Re: starship-design: FTL travel

In a message dated 4/14/00 9:14:31 AM Pacific Daylight Time, 
Chris.Walker@BSKYB.COM writes:

>  The point I'm thinking about is that if you're purely an explorer, and 
>  care about being able to sensibly communicate with people back on Earth,
>  then it doesn't matter if you can't employ FTL travel as long as you can
>  travel very close to 'c'. For, due to time dilation, you can comfortably
>  cover vast distances in what seems like a reasonable amount of time to you
>  (as the crew in Poul Anderson's "Tau Ceti" did). You have, in a sense, your
>  FTL ship. You get to travel round the universe and see a lot of sights in
>  your lifetime :)
>  Thinking along more practical lines though, such interstellar travel is 
>  likely to be funded by a corporation of some kind rather than a very 
>  (and lucky) individual who gets the chance to do the aforementioned jaunt.

Hi Cris.
All is needed is a practical engine. Patent rights to an individual on a 
starship class engine drives the cost of solar system exploration, mining, 
and colonization to fractions of pennies per pound (yea you heard that about 
nuclear power). Anyway on to business-funding for a star mission can be taken 
from license profits alone.

I do not believe that ground bounders can prevent that from happening. 
Mankind has dipped their toes in the ocean of space and ran back to mother 
earth like children on the seashore afraid to swim. Some dream of traveling 
to the stars. I just hope I am in the correct mailing list for believers. I 
was beginning to doubt from all the negativity about the possibility of star 
travel. What a demoralized group. How Come?

>  The point being that the corporation is going to want some kind of 
>  return in the foreseeable future for stumping up the cash to begin with.
>  They're going to want a *true* FTL ship - something that can travel from
>  Earth to a destination hundreds of light-years away and back within a 
>  (say). They don't care that travelling at a mere 0.9999c will make the trip
>  seem considerably shorter for the crew if they don't get their investment
>  back for a several centuries.
>  To sum up: we're discussing FTL travel from the point of view of being on
>  Earth. Travelling four light years at 0.89c and having the *crew* think
>  they're burning along at 2c (due to time dilation) isn't FTL.

True but it is the first step to realizing that FTL is possible for velocity 
aboard the ship can be correctly measured at 1c, 2c, 3c, .....n defined as 
warp speed 1,2,3 ..n.

Steve's distance calculation of seen 1 point some odd light years for a true 
4 light years distance does not hold to examination. Length is contracted by 
velocity on the ship only not the distance between the travel points. The 
rocket man measured the distance before and after stopping to determine the 
distance. measurement for him to measure the 4 light years with foreshortened 
rulers on board the distance would be greater than 4 light years not less as 
Steve has mixed frames of reference (like I just did with foreshortened 
rulers) to find a value supporting his theory of a c limit for rockets. His 
imagination (useful) is not trained and disciplined to a point where he can 
separate imaginary rockets from Einstein's thought experiments and focus on 
real rockets.
I use the "Tau Ceti" example to get students used to the idea of and 
calculating measuring velocities greater than C. I then introduce them to 
negative velocities and prove by analytic geometry that when an object 
exceeds light speed wrt earth it cannot be observed.

As there is not a velocity limit for rockets known then nothing is to prevent 
a rocket traveling greater than c wrt earth. I do not plan to shut my engine 
of while accelerating to beyond light  just because Steve is having a 
hysterical fit aboard ship thinking it will not make it. (Star travel is no 
place for girlie boys) 

I may just do what Columbus did on way to America and feed the crew false 
distance and velocity measurements to prevent mutiny. Steve can then discover 
returning to earth from the stars that his earth bound relatives are much 
younger than he calculated possible.

As Star ship commander my authority is absolute and is under Maritime Law 
extended into space beyond any national boarder jurisdiction. Punishment can 
range from me giving a shame finger (right index finger stroking top of left 
index finger) to instruction that you are endangering my ship, crew and 
mission so may be trapped in the fantasy world of my holodeck so turn in 
space suit and exit holodeck now and report to me. Exit by clicking Exit sign 
on holodeck at below link.


A rocket traveling at accelerating at 1 g wrt earth for one year exceeds 
light speed (approx 1.2 C).  shining a light for an earth observer towards 
earth the light travels at c toward earth but does not ever reach earth for 
the velocity of light wrt earth is neg point 2 c. This means that the light 
is indeed traveling toward the earth wrt the ship but because of its negative 
velocity is actually travelling away from the earth as velocity is scalar 
vector with both magnitude and direction. Freshman grasp the idea of negative 
velocities quicker than seniors for some reason in a basic physical science 
using cars and train examples. 

Were I to believe the cosmologists the stars at the edge of the universe from 
Doppler shift appear to be accelerating at near light speed. Objects beyond 
edge objects are concluded to exceed light speed though not visible for the 
above reasons. Siting in my chair my velocity wrt beyond visible universe 
edge objects is greater than light speed. Wrt a valid viewpoint (reference 
frame) I am exceeding light speed at this very moment.


>  Regards,
>  Chris