[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: starship-design: This and that.

In a message dated 6/18/97 5:51:16 PM, hous0042@maroon.tc.umn.edu (Genny
Houston) wrote:

>Hello everyone,
>I've been a little withdrawn lately, but now that school is over, I will
>be more active.
>I've just plowed through the latest messages, and I have a few questions
>and suggestions:
>To: Steve VanDevender
>Re: Traveling Faster Than Light.
>In message dated Sun Jun 15 1997 you write: (reformated)
>> More importantly, relativistic physics, as we now know it, 
>> does not in any way prohibit a material object from traveling 
>> at any speed less than C, but does prevent anything from traveling 
>> faster than that. 
>It is my understanding (limited though it may be) that Einstein's
>equations do not prohibit travel FASTER THAN the speed of light, 
>but only prohibit travel AT the speed of light.  Is this not correct?

Thats what I remember.  Of course that transition past C might be a problem.
 Its not a theoretical imposibility.

>To: Steve VanDevender
>Re: Talking Faster Than Light.
>In message dated Sun Jun 15 1997 you write: (reformated)
>> The few FTL effects that are thought to exist in particle 
>> physics don't translate to macroscopic objects, and even 
>> when postulated don't transmit information or mass faster 
>> than light.
>Again, my limited understanding tells me that communication via
>particle/wave duality phenomenom is possible.  Via the following method:
>1) Generate a single photon every 1/100 second.
>2) use a beam spiltter to give the photon a 50% chance of:
>	3a) going to your friend (or enemy) at Tau Ceti.
>		-or-
>	3b) into a trap for 12 years (perfect reflectors, whatever)
>Once the other photon has had enough time to arrive at Tau Ceti, send
>your 12 yr old photon into a double slit experiment.  Your friend (or
>enemy) does the same.  You both observe the pretty, pretty, interference
>Now comes the tricky part:
>You turn on a particle detector and are able to decide exactly which
>slit the photon went through. of course, your interference pattern
>disappears, but 
>SO DOES THE OTHER GUY'S (and at the same time too)
>After sending your morse code message, you turn off your particle
>detector and stare at the interference pattern again (pretty... 8)
>Suddenly the pattern begins disappearing in an orderly fashion as your
>friend (who is now your enemy for ruining your interference pattern)
>transmits his message:
>>>Hey, thanks a lot, JERK! you riuned my interference pattern :( <<
>Aside from the obvious technical problems of observing the same photon
>at the same time (whatever "same time" might mean)(and BTW I can finagle
>around that one too if you insist.)  This method should allow FTL
>communication.  and temporal communication as well.  Causality be

Sounds familure?

Oh, what do you project your interstellar interfearence pattern on?

>To: all
>Re: support of Kyle
>First let me (mis)quote Clark's first law:
>"When an intelligent but young scientist says that something is
>possible, he is almost certainly correct.  When an elderly but
>distinguished scientist says something is impossible, he is almost
>certainly incorrect."

Well its not always true.  ;)


>The Question I have:
>1) Why did the photon (as a wave) disappear from path (a)?

OH, I know this one!  To get the the other side? state?

<Well it worked for the chicken crossing the road joke!>

>2) How did the photon "know" to stop behaving as a wave and start
>behaving as a particle?

Instinct, pure instinct.

>3) if such a well-established princple of PHYSICS can be dashed by a
>simple thought experiment (which anyone could have done in the last 50
>years but didn't)
>	Then how can we say that FTL is impossible?

You close your eyes very tight, stick your fingers in your ears and screem "I
woun't beleave in FTL.  I woun't beleave in FTL...."

>It seems to me that Kyle has done a good first order approximation of
>his star drive.  He has told us the energy cost (10,000 times higher
>than the M.A.R.S. drive  ;)  ), it's rough size, shape and mass.

I must have missed the size and mass part.

>He has explained the first princples of it (although he claims it is 
>Non-Alcubierre FTL, (E-mail dated Mon, 09 Jun 1997) it looks a lot like
>the Alcubierre method)  
>You may say: "But how can one generate such a tremendous negative energy
>(or gravitation) gradient?"
>This is a valid question, but we might as easily ask Kelly how he
>intends (exactly now) to initiate a sustained fusion burn in his
>explorer class engines.  ----

Would you prefer pulsed?  <Noisy!>

>--We have the *feeling* that sustained controlled
>fusion is possible, but the only demonstrated method requires
>temperatures and pressures found only in the core of a star.  (H-bombs
>don't count, not controlled or sustained)(break-even fusion don't count
>Granted that we are a hell of a lot closer to fusion that we are to ZPE
>or FTL, but then in 1970 we were much closer to fusion than we were to
>personal computers. Now personal computers are everywhere  and fusion is
>still a pipe-dream.
>Kyle, you have a lot of work ahead of you, you are going to have to 
>explain in much greater detail each step of your design.  I suggest you
>start with ZPE even if FTL doesn't work, the energy from ZPE will be
>useful to other designs.  expect much critisism and argument from Steve
>and Tim, but don't take it personally.  they are not trying to be mean
>and nasty, they are trying to help you by making you state what you mean
>in very precise terms.  If you get stuck on the math, ask nicely, and
>you'll be surpirsed at how helpful they can be.
>If you look through all the old archives, you can see the same pattern
>when I brought up the MARS design.  Steve, I especially remember you
>telling me that there was "no way" the sail could take in photons, and 
>derive enough momentum in the reation mass to overcome the momentum 
>gained by the sail.  It wasn't until Tim solved the equations and proved
>that it was possible that you relented (although to be honest, my
>numbers and physics were far more out of whack than yours.)  And I
>suspect that Tim did it more to prove me wrong and shut me up than to
>help me.  ;)
>The Mars design has some serious Engineering problems, but the basic
>physics are sound, you can travel at near light speed if you can spend
>about 1E18 Joules for two and a half years straight.
>But FTL would be better, and ZPE would solve all of my transmitter
>problems :)
>Well, that's enough physics for now.  I have some things to say about
>generating Oxygen for the trip.
>To: all
>Re: Oxygen.
>I have figured out a way to recycle all the oxygen (and even extract the
>Oxygen locked up in the Stored food.
>Basic Food equation:
>C  H   O   + 6 O   = 6 CO  + 6 H O 
> 6  12  6       2        2      2
>As I've said before, the Water can be split into Oxygen and Hydrogen but
>what about the CO2?  We must continuosly dump it into the exhaust, or
>otherwise get rid of it.  But then i was thinking about the following
>equation in a book I had read.
>                 900c   
>24 H   +  6 CO    =   6 CH  + 12 H O
>    2         2           4       2
>The products of both electrolysis reactions is: 18 H2 + 9 O2.  So we
>must supply 6 H2 for each molecule of sugar.  
>Now This assumes that we have a lot of heat, but that's true of all the
>designs I've seen so far. (except FTL of course) The methane is then
>used in further synthetic reations to make the various chemicals we
>might need, or it can be dumped into the exhaust stream to increase the
>mass flow in the thrust.
>If our hydroponics are supplemented by stored food supplies, Then a
>bigger problem might be Oxygen retention, rather than lack of Oxygen.
>Kevin "Tex" Houston 

I beleave all the oxegen we breath gets converted to water by matabolism.  If
we electrolysize the water we produce, and burn the H2 + CO2 we should be in
great shap.  (I read this recently but forgot where.)