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Re: starship-design: Faster than light? hmmmm. . .
lot of this refers to a message dated Fri, 21 Jul 2000 21:33:50 EDT
Amazing. . . Never did I imagine that such an interesting event would occur
by me simply writing a message trying to dispel some of the mis-conceptions
dealing with the “gain-assisted superluminal light propagation” experiment.
Never the less, I will endeavor to offer any insight or offer any help
possible. I hope you may find me equal to the task.
In regards to the comment, “Mass would not limit a object to below light
speed. . .” here goes nothing. As has been pointed out to me, my thoughts
are hampered by my own math and experience limitations. My recourse is
simple but I believe it to be correct (if not, please correct me).
Einstein’s STR defines kinetic energy as the following:
K.E. = (mc^2)/ sqrt(1-(v^2/c^2))
To quote Einstein from his own book entitled Relativity: the Special and the
General Theory, “ This expression approaches infinity as the velocity v
approaches the velocity of light c. The velocity must therefore always
remain less than c, however great may be the energies used to produce the
acceleration.” You can’t argue with a definition unless you make a new one
(if someone has done this, let me know). It was said (by Dr. Jackson),
however, that Einstein forbid only the observation of this event and on this
I would like to hear more. If something has mass, it seems to me (based on
this definition of K.E.) that in order to reach c one would need an infinite
amount of energy. This also means that as you approached c, and you had
mass, it would take more and more energy to increase one’s speed by even the
tiniest amount (but I assume that most people reading this probably know how
I could arrive at this).
However, there is nothing in physics (again, to my knowledge) that says you
can’t go faster than the speed of light if you cross the light barrier in
less than planck’s time, but, again, the energy considerations for this
would be astronomical, I can’t begin to fathom it.
Again, I must stick to my original statement, “So you wanna go faster than
light. Ok. Just make sure you don't have any mass. ;)” However, this
doesn’t mean we can’t go faster than the speed of light if we can distort
space-time in some way I’ve never heard of. (i.e. find a loop whole in the
equations which can bring about zero mass or some other outrageous result).
I am not convinced by the statements you gave concerning faster than light
travel and mass. Not that I am not open to the idea of FTL, but I need to
see some real proof. *Sorry*
And on to the experiment. Just to clear up any confusion, I didn’t conduct
this experiment. However, I do believe in the validity and repeatability of
>1. Do you have a web page outlining a physics theory?
Its not my page, but here is the address. This experiment is based on
calculations, given at this address, from QM and is described there.
>2. Are you the sole author of this theory? If not, how many other
>people collaborated in its formulation?
Again, not my theory (and it was an experiment, not theory). I believe this
experiment is being published under three people.
>3. To your knowledge, is your theory known to the academic community?
The results are being considered for publication in Nature as I write this.
>4. Does your theory contradict a currently accepted theory? (If so,
>please briefly explain.)
No, this experiment doesn’t. The equations were derived using Einstein’s
own equations as well as QM.
>A few prolific authors and interpreters of Special Relativity Theory teach
>Millions of a >light speed limit for Mass. Einstein taught to a select few
>his special relativity theory >allowed for faster than light travel(FTL)
>for mass objects.
FTL is not a contradiction of Special Relativity, but clarification and
derivations of velocity equations beyond light speed.
(And as a side note on faster than light travel. It is interesting that
faster than light particles, called tachyons, have already been predicted by
theory. For tachyons, it takes energy to move slower. In fact, tachyons
have the same problem with the speed of light that we do. Much like we have
problems going faster than light, tachyons have problems going slower than
light! This is just a hypothesis and has not been proven, and can’t be with
the experimental methods we have used thus far.)
>5. In your opinion, on a scale of 1-10 (10=absolute certainty), how
>likely is it that your theory correctly explains physical phenomena in
>our universe? (i.e., do you just think it should be considered as a
>possibility, or do you think it's definitely the answer.)
Again, its just a neat experiment that proves what we already know.
>9.99 as I consider Einstein a credible source and his FTL theory as
>testable by >unobservable experiment and provable by logic. A theory of
>velocity limit at c is >speculation unsupported by factual evidence or
>credible logic. A limit of c is not even >a theory but only uneducated
>guess at best.
(As far as this goes, I believe this to be, at best, wrong. But, than again
it was kind of a subjective statement. Einstein is a credible source, I
agree. “A theory of velocity limit at c is speculation unsupported by . . .
credible logic”- very doubtful. Einstein’s own equations, indeed, seem to
suggest a difficultly of reaching “c”. i.e. The energy you need to
accelerate increases exponentially as you approach c. In fact, remove the
speed of light as a constant and Special Theory of Relativity falls (I
cannot speak to the general theory yet because the math is at too advanced
of a level for me at the present time.) STR was created with this (light as
a constant) as one of the original, assumed postulates! If you accept this,
the idea that “c” requires an infinite amount of energy to reach necessarily
follows. Again, *sorry*. I don’t buy it (but I am open to suggestions that
would lead me to a different conclusion).
>5. What is your physics background? Please indicate how much formal
>academic training you've had (high school, college, etc.), as well as
>other resources you've used to learn physics.
Yes, I’ve graduated high-school. . .he he he. Presently, I am earning a
degree in Physics and Astronomy, with minors in Math and English @ Drake
>6. How old are you?
I really believe that age should have very little to do with credibility.
Because this question implies (to me) that the older you are, the more
credible you are, I will not answer it. Credibility has nothing to do with
age, but deals with experience. (Based on my responses, however, you can
probably guess my age, and I have already given you my experence).
>7. What do you do for a living?
Based on how things look now, I’ll probably be a student for the rest of my
life (or at least the next 6 years.) ;)
>8. Do you expect to be eventually recognized for your work? (If not
>credited during your lifetime, then at least historically vindicated.)
Again, not my experiment and yes. I hope I can play a part before I pass
>9. Briefly, why do you study physics?
I can’t hope to answer that. ;) I’ll let Q do that, lol.
“We hoped to open your mind and your horizons and for one
brief moment you did. In that one fraction of a second you were open to
possibilities you have never considered. That is the exploration that
awaits you. Not charting stars and exploring nebula, but exploring the
unknown possibilities of existence.”
Wow. That was a lot of work. Most of you probably know much more than you
ever wanted to know about me. Again, sorry about that. Now on to “applied”
I believe that a star ship design based merely on the use of fission for
energy (i.e. fission bombs) is simply much to energy inefficient for anyone
to dream of investing in for any kind of interstellar journey. I believe
that fusion and antimatter are really the only methods that provide enough
energy based on the amount of fuel needed (this means I stray away from
projects like the orion, because nuclear fission bombs simply do not convert
enough matter to energy, while antimatter/matter reactions have a
theoretical 100% matter to energy rate. . . .and yes, I realize the present
limitations in creating antimatter). I believe that a system proposed at
has some real promise. The following is the gist of what I believe,
currently, holds the most promise for an interplanetary method of propulsion
“The promising concept that Cassenti and NASA are investigating,
magnetically insulated inertial-confinement fusion, employs a unique
combination of fission, fusion and antimatter. The concept derives partly
from attempts to have high-energy lasers implode targets of deuterium and
tritium (D-T -- the heavy hydrogen and heavy-heavy hydrogen used in most
fusion studies) to produce power. Kammash suggested replacing the large,
fragile lasers with a quick squirt of antimatter.
Cassenti described the targets that would be used in such a scheme: only 0.8
inches (2 centimeters) across (less than half the width of a ping-pong ball)
and just 0.1 ounce (3.5 grams) in mass. Most of the target is deuterium and
tritium, with a hollow core and a small chip of uranium 238 to one side. The
D-T pellet is coated with uranium to serve as a neutron reflector, and that
is coated with tungsten to help contain the blast just for an instant.
In operation, a target is dropped into the combustion chamber and a stream
of antiprotons is fired through a pinhole into the core. This triggers
fission in the uranium. Neutrons reflect off the uranium shell, and freed
electrons form a magnetic field to confine the D-T plasma long enough for a
small fusion reaction.
Theoretically, Cassenti said, such an engine could have an Isp of up to
200,000 seconds, although the practical limit is 9,000 seconds -- more than
19 times as efficient as the shuttle's main engines. And unlike most other
schemes where high Isp also means low thrust, the pulse propulsion would
have a real kick.
Firing at a rate of 136 pellets per second, the pulsed fission-fusion hybrid
would accelerate a ship at 1/5 G for extended periods.
"You could get to the inner planets in less than a week," Cassenti said.
"This is tourist stuff." Jupiter would take less than a month, allowing
"We would provide a way to open the solar system," Cassenti said. "The solar
system can be settled and you can do trade -- and it can actually pay for
A test of the principle may be just a few years away, Kammash explained.
Marshall Space Flight Center is investigating basic methods with a Van de
Graff generator that will produce high-speed beams of protons aimed at
fusion targets costing about $5,000 each. With this they can learn to
position the target and aim the beam.
"Then it becomes really exciting," Kammash said.
Pennsylvania State University is developing a Penning trap, a Star Trek-like
magnetic bottle that will hold a small quantity of antiprotons, carefully
trapped and cooled after they come flying out of an atom smasher in other
experiments. It will hold a paltry 1 trillion or so antiprotons, just enough
for one test shot.
"How many times you can do this depends on how many times you can go back
and fill it up," Kammash said. But that may be enough to demonstrate the
high-octane fuel that space enthusiasts have been seeking to open the
-taken from www.space.com
Well, everyone who read this entire thing. . . .congrats. It was long and
I’m very tired. I hope this helped someone learn a little more about
something or at least provided some entertainment at my expense. ;)
PS: My hats off to you Dr. Jackson.
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