Re: Re: Summary A

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

To Kelly,

>> This assumes you can quite accurately steer a packet, 
>> but a packet is build up of a lot of small particles all 
>> going their own way (of course mainly forwards). ----
>
>Who says?  A fuel packet could be the size of a fright car of that would
>help, but I'ld assumed it would be smaller.  More like pill to bear can
>sized.  It would almost impossible to spray a charged fog of particals out of
>a gun and keep them together.  Their mutual repulsion would cause them to
>defuse to much.  You'ld have to pack them in mini-containers.  I supose you
>could treat those containers or packets as particals, but I don't think thats
>what your thinking of.

Yes, you are right, lets assume packets of 1 kg. Can we accelerate them up
to 1E8 m/sec in an accelerator of a few hundreds of metres?
I guess, I'm a little overwhelmed by the amount of energy again, but
forgetting that, are you planning to use magnetic or charged acceleration?
Let do a quick calculation about the acceleration needed:
v=x*t  a=v*t --> a=v^2/x = 1E16/100 = 1E14 m/s^2

>>>I really wish I had some numbers on the power a mag
>>>launcher takes
>>You could calculate the least amount of energy very easely
>>if you know the exhaust speed and the amount of mass 
>>per second.
>If you send the equations along I'll run some numbers through for my summary
>documents.

Non-relativistic: Power needed = 0.5 M Vexh^2 Watts
  M=Mass per second  Vexh=exhaus velocity  (I'm sorry that it is so simple)

>You could rig up the systems to degrade in capacity not just fail.  But the
>more detailed the structures (like the inside of Nanos) the more slight
>defects will disrupt the function of the system.  (I'n not optimistic about
>Nanos longevity in radiation fields.)

What I was hoping is that the quantity could overcome the quality: A lot of
nanos could undo the work of a few broken-nanos. Untill the amount get 75-25
still a lot of work can be done. Of course this doesn't rule out the
statistical breakdown after a longer period. But only the few extremeties,
like the 1:1000 chance of not working directly after manufacturing.
I'm quite sure that if we made chips today with size as 10 years ago, we
could make them much more robust.
OK, all in all, redundancy only works to reduce the number of incidences,
but not the total "decay". But the number of incidences may be quite high
without redundancies.

>> The only problem is that higher-tech (not highest-tech) 
>> has only few redundancies because that isn't efficient 
>> in our society.  About highest tech, we won't be using 
>> that much, since it is inherently dangerous to use systems
>>  that haven't proven their workings enough.
>
>Redundancies start to drastically degrade the performance of some systems
>(like I.C. chips), and we may (or may not) need all the performance we can
>get for a starship.

Maybe this is something that we did not dig out enough, we all assumed that
the engine designs we came up with would work without much problems for most
of the time they were needed. But is it really that easy? I wouldn't like to
have two enormous engines and one of them suddenly(?) stops working. In the
best case we could turn of the other within time. Worst case, the starship
would start to rotate an be ripped apart by all the abnormal g-forces.
Besides this, can we savely have an engine shutdown for say a week. I can
imagine that for beamed energy this may be a problem. (eg. Non matching
speeds of beamed matter). So how much backup do we need, does it mean that
the whole ship gets twice as big?

>Anyway, in a political arena peoples techno prejidices will effect the
>projects and the protest to them.  Every analysis of nuclear powe shows its
>not capable of poluting as mouch as the coal plants it would replace.  Yet
>nukes get intense public and governmental polution and safty attention, coal
>little.

Yes, it's sad, however a single mayor error in a nuclear plant can make a
whole country (like the Netherlands) inhabitable for a long time.
Anyway lets hope fission or renewable energy will soon replace most of them.

>> Are you also thinking that hibernation is more or less 
>> trivial? 
>
>No, just that I beleave the public thinks it is.  But in politics reality is
>unimportant, impressions are everything.

Indeed, maybe it is time to start a (yet another) new science fiction series
to promote our ideas and collect money by selling T-shirts, computergames
and stocks for our company to be (Live internet discussions and camera shots).
(I'm not really kidding...)

Timothy