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Re: starship-design: Re: FTL travel
Steve VanDevender wrote:
> I think I know where you're coming from, to the extent that I've seen
> you express support for "alternative" physical theories like
> I think _Spacetime Physics_ expresses the formulation of relativity that
> is in mainstream physical thinking, and its explanations are much
> clearer for beginning students than those in other texts I've seen.
> It's no more dogmatic than any other physics text I've read;
that's scary . . .
> what you
> call dogma I see as emphasizing the simple fundamental ideas behind
> relativity theory. Invariance of spacetime interval in relativity is
> just as fundamental an idea as the invariance of distance in Euclidean
> geometry; the parable of the daytimers and nighttimers is meant to
> emphasize that while you can choose different coordinate systems in
> which the same location has different coordinates, there are geometrical
> invariants that apply to any of coordinate systems one might choose.
Sure, polar vs. cartesian, and the day- and nighttimers _will_ agree on the
_distance_ to the point in question, but they will _still_ argue about its
_location_, because they still have differing compass references, one magnetic and
one celestial. Sorry I had to throw that in, but the authors should have caught it.
> Similarly, in different relativistic frames, one measures different
> coordinates for the same events, but the spacetime intervals between
> events that one obtains from those different coordinates is the same in
> all frames.
I understand this concept as presented, but I have a problem with it -- see below
> And since a great source of confusion in students who are
> learning relativity are things like the seeming twin paradox, spending
> time on explaining why the seeming paradoxes aren't really paradoxes
> makes a lot of sense to me.
I'll buy that, but I seem to recall them presenting some paradoxes which they
admitted to being insolvable. I could be wrong on this, though.
> I think anyone who studies the history of science knows that while many
> scientists in a particular time think they have the definitive laws of
> physics, what science does over time is obtain an increasingly precise
> understanding of the underlying laws of nature. Newtonian physics was
> successful for so long because every experiment that was possible to do
> during its reign confirmed its results; the major hurdle relativistic
> physics had to overcome to be accepted was obtaining the experimental
> proof that showed it worked better than Newtonian physics in the domains
> that previous experiments had been unable to test.
of course . . .
> If something better than relativity is to come along, to be accepted it
> will need to make predictions measurably different than relativity, and
> then have those predictions be proven by experiment.
harder yet, it'll have to overcome money (private, public, and institutional) and
politics (governmental and academic).
> I don't promote
> relativistic physics because I think it's the be-all and end-all of
> physical theories; I promote relativistic physics because it's clearly
> the best experimentally-verified theory we have now. I'm willing to
> change my mind when something better comes along, but I haven't seen
> the better thing yet.
Could you comment, please, on Gaasenbeek's work? (
www.rideau.net/~gaasbeek/index.html#contents ) Like I say, I'm not a scientist, but
I like this better than Autodynamics.
The reason I liked both of the above has to do with the problem I mentioned
earlier, about the invariance of interval. The problem is, that I don't think it's
right, and both AD and Gaasenbeek's theories do away with its resulting paradoxes,
time dilation, etc. Let me explain as best I can.
Time is not a property of matter; if it were, we could answer the question, "How
many minutes are in that glass of water?" Time, to me, is strictly history, and
cannot be properly related to anything physical, either matter or space; it's
merely an intellectual construct used to relate events chronologically. Note that,
in a universe with only one event, there is no use for the concept of time.
Since matter takes up space, those two are related, but just for fun, consider that
in a universe with only one object, there would be no use for the concept of space
(and yes, I know that this object would have to be dimensionless and therefor only
theoretical). Space, therefor, is our way of relating objects physically, similarly
to the way time relates them chronologically.
Strictly aside, I'll throw energy in with matter and space, but I will now indicate
that time still doesn't belong with them, or else you could answer the question,
"How many seconds are there in a watt?"
Now, Lorentz (I'm going to blame him here, because _Spacetime Physics_ said it was
his idea) took a concept which dates back to prehistory: that distance can be
_thought of_ in terms of time ("How far to the next oasis?" "Half a day on foot.")
and applied the Pythagorean theorem to the combination, getting his invariant
interval as the result. Note the emphasis: _thought of_. Just because time and
space can be related to one another (by the necessary inclusion of a velocity term)
_does not_, to me, mean that the two can be _substituted_; they are two altogether
different things. It's like, say, vitamin C in food; you could make up tables
showing that so many tomatoes have the same amount as so many grapefruit, but you
wouldn't want to substitute grapefruit for the tomatoes in your marinara sauce. And
yes, that's a sloppy analogy, but you are grinning, aren't you?
So you can see the problem I have with relativistic physics, and the appeal that AD
(or, better) Gaasenbeek's ideas have for me. To me, they explain the universe more
logically. Take two examples I recall from Taylor & Wheeler: one states that a ship
going in a straight line will take longer, at the same velocity, than one going
zig-zag; another states that a ship doing a round trip at constant velocity will
take longer going out than it will coming back. I'm sorry, folks, but this just
seems schizophrenic to me.
A big part of the problem, as I see it, is linguistic. Look at the everyday
references to 'time' in our language: we speak of time as a corporeal commodity
which we can buy, save, lose, trade, and of course, never have enough of. But since
time isn't physical, this all amounts to linguistic garbage; we're speaking of
something in terms which cannot apply to it. We allow such garbage into our
linguistic concepts because it's convenient, we forget that it's garbage, and then
we unthinkingly corrupt other concepts with this convenient garbage. It's like
programming a computer with corrupted algorithms. What makes this so dangerous is
that it is now known that the _words_ we use actually affect our thought processes,
the very way our brains work, meaning that, for us to carry corrupted concepts in
our language causes our brains to dysfunction.
Now, here's one that'll really ruffle some feathers. This was an idea I had wanted
to follow up myself, but I doubt I could handle the math, and the scope of the
research is likely beyond me as well, but . . .
Limiting the topic to space-time physics, relativistic physics, whatever you want
to call it, what would you have if you went through all the pertinent equations and
removed all "time" terms from them?
Think about that one for a while, while I apply some refractory ceramics to my
Keep looking up,