Name: David B.
I just read Kenneth Salem's book, 2.8 angstroms.his
theory claims that we, our galaxy is already traveling at, or near the
speed of light,and is slowly accelerating at 2.8 angstroms. He also
claims that this is reason why light propagates at a starting speed of
instead of a starting speed of zero. This slow acceleration of 2.8
angstroms is also the reason we feel or have gravity. He also says that
the speed of light is not a universal constant as we have been told by
Einstein's theory. Is any of this true?
Sounds like science fiction to me for the following reasons: 1.
Acceleration is the rate of change of speed (velocity) per second, so the
dimensions of acceleration is (meters/sec)^2 which is not the dimensions of
wavelength which is (meters).
Very recently there has been some conjecture that the speed of light in the
early formation of he the universe may have been different than it is today.
But that is very much speculation. The best measurements to date show no
change in the speed of light. In fact, the length of the meter has been
redefined in terms of the speed of light.
Third the speed of light is not a consequence of Einstein's theory or
relativity, James Clerk Maxwell introduced this in his treatment of
electromagnetic theory that pre-dated Einstein's work by a generation.
Finally, the nature of the gravitational force is not understood, to my
knowledge. We know it exists. it appears to propagate at the speed of
light. We know how to calculate its effects on stars, planets, and
satellites very accurately -- but do we have an understanding of what it
is, and why it is so much weaker that all the other forces of nature. I
do not think so.
Do not let that stop you from reading science fiction, however. It is fun, we
just have to suspend our sense of physical and chemical reality when we read
And occasionally, it turns out to be closer to subsequent reality than we
I do not know whether it is true or not. A person must understand an
important property of physics: we do not know whether any of it is exactly
true. It is a model, perhaps an approximation, for trying to understand and
work with the physical world. For example, we know Isaac Newton's laws of
force are not correct. However, we also know that in most situations they
are an excellent approximation of what really happens. All theories are
used so long as experiments and measurements support them. If a theory
correctly predicts what will happen in many experiments, and if the theory
is convenient enough to make it worthwhile, scientists will use it. I have
not read the book to which you refer, but I do know some data indicates that
the speed of light is changing VERY SLOWLY: an almost immeasurably small
amount over billions of years. In most situations, it is reasonable to say
that the speed of light is just about constant.
Dr. Ken Mellendorf
Illinois Central College
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Update: June 2012