(urth) Short Sun blog review

[Jack Smith]

A few points about the speed of the Whorl;

1.  You have to travel very fast to get to any stars because of their great
distance.   To reach even the closest star in 300 years, you would need a
speed of about 1.5% of light (10,000,000 MPH).  You would need some
fantastic source of energy to get the Whorl to even 1.5%,  a source that
will only be found in the future.  Wolfe says the long sun is powered by
nuclear fusion, but he doesn't tell us what propels the Whorl.  I think that
is because he knows that no such power source exists yet.

2.  95% of light speed requires even more energy, of course.  But as long as
we are tapping into an unknown power source, we might as well go as fast as
we can.

3.  A travel speed close to the speed of light explains why only 300 years
have elapsed on the Whorl while 1000 to 2000 years have gone by on Urth.
  At 95% of speed of light, Whorl time would be 300 years for 1000 Urth
years.   At 99% of speed of light, Whorl time would be 300 years for 2000
Urth years.

4.  Of course, it's more complicated than traveling the whole way at one
speed.   You have to accelerate the ship up to a high speed, and then
decelerate to stop at Blue-Green system.  The rate of acceleration has to be
slow, or the cargo would be pressed against the back of the ship.

Acceleration  would have to be very low.    At an acceleration of 1/100 G,
it would take about 97 years to get up to about speed of light.  You could
then coast for 100 years, and then decelerate for 97 years,   making a total
time of about 300 years.






On Tue, Sep 21, 2010 at 2:38 PM, James Wynn <crushtv at gmail.com> wrote:

>
>  Jack Smith-
> " I think I've heard estimates the Whorl is at least 300 years
> old. Typhon was presumably alive on its launching and is still alive when
> Severian meets him
> strapped to his couch. Quite a lifespan."
> Isn't Typhon dead when found by Severian, who then resurrects him?   Typhon
> seems to have dried out after lying on the cold, dry mountain for 1000 or
> 2000 years (in contrast to Dorcas, who is soggy).
> Since the Whorl has traveled near the speed of light on its voyage, time has
> slowed down.  So 1000 or 200 years can have passed on Urth, while only 300
> years have gone by on the Whorl.
>
>  Gwern-
> I don't remember if our past discussions went into the technical
> details, but it's pretty unlikely the Whorl got any significant
> slowdown.
> Useful link: http://www.projectrho.com/rocket/rocket3aj.html#relativity
>
> Notice that to get a slowdown of even 1/3, you need to get up to
> somewhere around 0.97 or 0.98 _c_. Given that we're talking an entire
> hollowed-out asteroid, and one which needs to slow down to rest at the
> end... Well, the energy requirements would be absolutely fantastic.
> (And I mean fantastic as in, you'd better have an entire other
> anti-asteroid made of anti-matter for propellant.)
> Dunno if Wolfe took all this into account, though.
>
>
> In the Urth List Q&A, Wolfe said:
>
> *Q: About how far, really, is the New Sun series set in our future (or the
> future of the previous universe)? How much time elapses between Typhon and
> Severian?*
>
> A: That is never specified in the books. My offhand guess is between 1000
> and 2000 years. I would have to reread the books with care to perhaps trim
> the estimate up a little bit.
>
> However, since Dream-travel can involve Time-travel, all of this might be
> academic as far as the Rajan's visits to Urth go.
>
> u+16b9
>
>
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-- 
Best wishes,
Jack
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