Re: Re: Summary

[T.L.G.vanderLinden@student.utwente.nl (Timothy van der Linden)]

Also to Kelly

>I'm just saying that there is a limit to the amount of information that can
>be transmitted inteligably over interstellar distences even is your playing
>with all the usable spectrum.  Obviously the local star(s) will drown out
>most of the frequency bands, given that earth scopes will be looking straight
>at it.  So we will eiather have to make due with that stars quiet bands, use
>incredible amounts of power (you really want to out shout a star?), and use a
>lot of low bouad and error correction to make up for interfearence.

There indeed will be a limit but is that limit really to small? These
SETI-programs seem to scan many bands, and their telescopes are pointed
directly at the stars. I assume they have made some calculations about
Signal to Noise ratio. I am not saying that it is easy but we were more or
less assuming we could use a beam to propell the starship. If we are not
able to propell a starship with it we certainly could use it as a
transmitter for information.

==============================================================================

>> >Thats a possibility.  It certianly would be politically less likely to be
>> >funded allong its entire history.  But given that expenses would be spread
>> >out over a longer time it might cost less over a given period of time.
>> >
>> >I'm surprized you objected to this section thou, since its the only option
>> >(i.e. assured routine supply flight) that woulkd allow a colony mission?
>> 
>> I'm just being consequent.
>
>Consequent?  Is that the word you ment?

Does that word not exist in English? I meant consistant.

==============================================================================

>A simple system like a fuel launcher that only has to work for a couple
>months every few deacdes should be able to be automated once its set up.  And
>making redundant copies will assure acceptable relyability.  Also the first
>thing eveyone does when entering the system is repair the fuel launcher.

In this conclusion you say that it could work automatically for a few months
or so. Could we really trust such a big machinery to keep on working for
several months (if not a year)? Because when it doesn't, that means we are
doomed. Besides that I can recall some one saying that an Earth-based
launcher would be better than a ship-based launcher because of the amount of
people needed to operate it (and because of the weight that the ship doesn't
need to carry, but that isn't discussed here).

>I wasn't building a mirror (what i the hell would it be for anyway?), and
>colonies need air and water recyclers, housing for humans, furniture,
>hospitals, and a lot of other things that a automated platform wouldn't need.

What makes an air & water recycler so much more difficult to build than a
launcher? Indeed a launcer doesn't need medcine or food but it needs large
amounts of well refined fuel.

==============================================================================

>> We are not talking about religious groups. ---
>
>Well obviously only a very 'focused' group of beleavers are going to condem
>themselves to perminent imprisionment for a multi-gen cause.

I wonder if that is really true, there are many people who have a focused
goal, but that doesn't mean that they are no able or not allowed to think
for themselves.

>> On a multi-gen ship there will also be a scientific crew, they are
>> explorers. If then need some practical experience, they will have all the
>> time they need. Simulators for shuttles and vehicles could do a great job
>> helping them.
>
>You can't simulate exploring planets in the confines of a vitual reality
>simulator, nor can you learn everything about fliying high performance
>aircraft without flying them.  None of which can be done completly in a sim.
> In a multi-gen crew.  Nothing anout exploration, not even seeing a real sky
>or horizon would be familure to them.

Indeed they would not have experience walking through the landscape etc. But
they could learn fast enough. A multi-gen ship would not need to examine the
star-system within a small period. If they wanted they could take a few
generations. They would be excellent objective observers since they wouldn't
know very well what Earth was like. Flying aircrafts perfectly isn't
necessary, as long as the flight and landing is reasonable smooth that is
enough.

>> It's a big risk trusting your live to a automated system on which you would
>> have no control. A single programming error can shut down the power source
>> and there would be no one to turn it on again.
>
>Compared to the dangers of a colony, thats trivial.

At least one has the idea that it can do something about it when living in a
space colony. And why should a space colony be so significantly more
dangerous than a 5 year flight in space?

>I agree that hibernation is risky technically and unsafe.  But that doesn't
>effect its political risk.  Politics is about impressions, not realities.

The media would certainly point at all possible difficulties, certainly such
obvious ones.

=============================================================================

>>When there is life it will almost certainly have some acceptable
>>temperature.
>
>Life can survive and thrive in a lot of environments that we could possible
>survive.  Temps of hundreds of degrees F, radiation, low grav and presure,
>deep oceans etc.  I don't remember anything in the LIT charter that suggested
>an earth like ecosphere.  It didn't even have a planet anywhere clse to earth
>in mass.  The charter was just we found a solar system and people wanted
>someone to go and check it out.  It never said they'ld want to colonize it.

OK, I forgot that.

=============================================================================

>> So, do you know how to solve it without having a big industry at the remote
>> end of the trip?
>
>You could save the light high tech parts of the stages (fuel processors,
>power systems, etc) and throw away the heavy structure and tanks.  That might
>allow you to rebuild the heavy stuff in the starsystem from local ores, and
>refit it with the salvaged parts of the old stages.

I wonder if any part at a rocket engine can be regarded as not hi-tech. And
if it is, it still takes quite a while to rebuild and assemble all the
parts. You don't want several parts to break down while you are on your way
back.

>However you should note that staging quickly requiers a HUGE ship.  You
>quickly might need to mine a starsystem for fuel.

It's the use of fusion-fuel that causes this, staging is a result of using
fusion fuel. (Just a minor difference)

>> How where you going to use that heat then?  Does it matter that 
>> much if you are first tranforming the heat into electricity?
>
>The Bussard reactors, and the fuels they use; don't produce radiation, heat,
>or the rest.  The power comes out as charged fast moving particals.  Those
>particals can be run past a magnetic feild for almost perfect conversion of
>the fuels power to electricity (with virtually no thermal load) or released
>as a reaction mass.

I really wonder how this works, does the LIT-page about this, cover that part?

>I've seen several major physivs papers talk about the theoretical consistency
>with FTL and time travel, worm holes and the like.  Also some are
>interpreting the one hole show partical, two hole shows a wave, experiments
>as showing ftl feedback.  Also by def, quantum shifts of electrons happen
>instently.

Not exactly, it always takes time to tunnel but at a certain tunnel-length
the "travel time" does not become any longer.
This indeed, makes it look as if the electron (wave distribution) has
travelled faster than light. But it seems that the front of the wave-packet
did not move faster than light. But somehow during tunneling the packet
became smaller and thus the center of the packet was shifted forward a
little. The center of the wave gives the biggest probability of detecting
the particle.
I can't explain any more right now, since the scientists aren't sure either.

In wormholes or other places where space is bended, the local speed of light
is still the same. However the global speed may indeed change. The same
thing happens when you are moving (at near light speed).
If we could bend (warp) space than indeed global ftl would be possible. But
then you would need to prepare a passage before you could fly through it.
A ship that would bend its own space would not be able to globally fly ftl
because it still needed to move that bended area at a speed slower than
light. It's global time would slow down though, so they would think they had
crossed the area in a shorter time, but when they would return to their
homebase they would notice the same effect as if they had been flying at
near light speed.
Of course all this assumes that space can be bended enough be artificial and
usefull ways.


Timothy