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Old February 8th 07, 10:24 PM posted to rec.radio.amateur.antenna
Jim Kelley Jim Kelley is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Antennas led astray

Michael Coslo wrote:

Cecil Moore wrote:

Michael Coslo wrote:

All parts of any given galaxy are not moving toward or away from us
at the same speed, unless the galaxy is perfectly perpendicular to us.



True, but consider that the red shift frequencies
are discontinuous, i.e. quantized.

Is your red-shift issue about the red shift itself, or about the
magnitude of the shift? And if "variable seconds" is the culprit, how
are blue shifted stars accommodated in your model?



My issue is that red-shifts are not necessarily
100% Doppler effects.




Of course there is gravitational redshift too, but I don't think that is
what you are referring to.

I think you are trying to say that time is variable (forgive if I err)
This means that the speed of light is also variable if only by relation
to that variable time element

Doppler effect is readily observable at audio and RF wavelengths. It is
widely accepted that the effect continues at light wavelengths.

Any effects that alter Doppler at light wavelengths should also be
noticeable at to wavelengths. I have not heard of any such, have you?

This then says that we are not in the "fastest time" zone, because there
are celestial bodies that are blue shifting toward us, or perhaps
not,they are just in a different "time zone"? ;^)

BTW, I erred in my perpendicular statement above. I forgot about
transverse Doppler shift that we would indeed have in a galaxy at right
angles.

- 73 de Mike KB3EIA -


There is an interesting (hypothetical) effect - and maybe this is what
Cecil is talking about. Two systems; A and B, we're A. System B is
moving away from us at relativistic velocity. Sodium yellow light
from system B's street lights looks red from where we're standing in
system A. Lets say we can also measure the atomic transition
frequency of the sodium atoms in system B's street lights and discover
that it resonates at a lower frequency compared to our reference
frame. [Note that if the velocity between the two systems is indeed
relativistic, then visible light will be shifted down into the
infrared. Also note that if we could observe the diaphram of a car
horn as it approached us, we would see that its frequncy of
oscillation visually would be higher than its doppler shifted audible
frequency.] If we assume that sodium behaves the same way everywhere
in the universe (which we usually do) and it transitions at
universally the same frequency everywhere, measured with respect to
its own reference frame, then there must be a difference in the length
of the unit time between the two reference frames in order to explain
the apparent observed frequency difference. We usually assume the
Doppler effect is linear with velocity, but temporal effects are
assumed to increase very non-linearly as the speed of light is
approached. So at modest velocities the apparent shift would be all
doppler, but at relativistic velocities the temporal aspect would
become more significant. I believe this is one explanation for the
apparent 'acceleration' effect, where you look far enough out and
things appear to be accelerating away from us, not just moving away.

73, ac6xg