From: tzf@csl.biosci.arizona.edu (Theron Friedman)
Newsgroups: alt.paranormal
Subject: Re: UFO's
Date: 2 Sep 92 21:09:32 GMT
Reply-To: tzf@csl.biosci.arizona.edu
Organization: U of Arizona, CS Dept, Tucson

In article <1992Sep2.172113.23387@csc.ti.com>, alanj@dadd.ti.com (Alan Jones) writes:
|> In article anson@netcom.com, anson@netcom.com (Anson Kennedy) writes:
|> >
|> >The limit of the speed of light in a vacuum has been experimentally
|> >verified countless times since Einstein published his theories.  Hopefully,
......
|> 
|> Uh, how does one experimentally "prove" that the speed of light cannot be
|> exceeded (by light or anything else?)?  Sounds to me like you're trying to
|> prove a negative, which is most cases is impossible.

What Einstein did in relativity (special theory) is took explained some
previously anomalous results by _postulating_ that the speed of light
in a vacuum was a constant TO ALL VIEWERS, regardless of their apparent
motion relative to the source. From this starting point, with the aid of
a few more assumptions and lots of high powered math he came to a number
of conclusions, which not only explained the previous results but made a
number of (non-Newtonian) predictions which have since been verified. So
relativity is the current reigning theory, at least for the physics of
the macro universe.
	According to these same equations it would take infinite energy
to drive a massive body to the speed of light, and at that point it would
acquire infinite mass. That's the barrier. If anomalies are found which
don't fit in the Relativistic theory, then perhaps the next theory will
allow for FTL travel. Current theory - which means current best guess about
how the universe is put together - says it can't be done.

	However, the left hand gives as the right hand takes away - long
ago someone noticed that these equations did allow for things in the universe
which went faster than light, but never any slower, the tachyons mentioned in
a previous posting. Right now this is purely a mathematical game and a SciFi
concept (often used to posit FTL communications, while physical travel is
still limited to sub-light speeds). The problem here is that such particles
would have "imaginary" mass, which is nice math but has no current physical
interpretation.
	The other possibility opened up by relativity comes from the concept
of "curved space". This is usually envisioned as a smooth curve, such as the
surface of a balloon, but there's no intrinsic reason that there couldn't
be much more complex structures in the curvature. Thus we have the idea of
"wormholes." No evidence for them yet, but we haven't explored out there
much so far. Here the barrier is more Occam's Razor than it is physical
theory.

Back to the main topic: UFO's definately exist. As others have pointed out,
the matter turns on the "U" part: there are some things which just haven't
been identified. I'd love to believe that they are alien visitors, but
personally I don't. It's a useful exercise to speculate, based on our
current knowledge, on the odds. But anyone who argues categorically that it's
impossible is IMHO building a house on quicksand. There are enough problems
in both cosmology and atomic physics that might dethrone current theory;
our biology and medicine are still in their infancy, psychology we only
start to understand, and even mathematics has opened up new frontiers in the
past couple of decades. A dash of humility about our understanding of what's
_really_ happening in the universe is definately in order.
Newsgroups: alt.paranormal