I have run across the following paper which shows a superluminal object within our galaxy. They correctly point out the "Relavisitic Illusion" as being the cause of the superluminal velocity by citing its "Blue Shifted" data.

My question before was and remains why such blue shifted data is not being found or cited for the other 100 or so superluminal objects which are casually accepted to just be an illusion.

When we had this discussion before some here tried to claim that blue shift couldn't be found. I complained that it should and that in absence of blue shift the velocity had to be considered v > c until a suitable explanation was given; which would require a reconsideration of the v = < c conjecture of Relativity.

So blue shift is seen for these objects which come at us with relavistic velocity. Why do some superluminal objects not give us blue shifted data?.

http://mist.npl.washington.edu/AV/altvw71.html

When you're looking at quasar jets and the like, I imagine that the jets are multi-spectral rather than monochromatic. If we don't know what the unshifted spectrum is supposed to look like (because it is approximately uniform), then we won't be able to determine blue-shift either.

Just a guess.

James R.,

Thanks for your input.

I have found another paper which I think deals with this issue more extensively than anyother I have seen. It addresses a multitude of considerations and data over several pages.

The following are extracts from that paper.

http://nedwww.ipac.caltech.edu/level5/Kellermann/Kell6_3.html

Attempts to understand the superluminal motion have produced a flurry of imaginative phenomenological interpretations including

(a) real tachyonic motion;

(b) grossly incorrect Hubble constant or non-cosmological red shifts (Kellermann & Shaffer 1977, Burbidge 1978) or incorrect cosmological model (Segal 1979);

(c) light echoes (Lynden-Bell 1977, Lynden-Bell & Liller 1978);

(d) gravitational lenses and screens (Barnothy & Barnothy 1971, Chitre & Narlikar 1980);

(e) systematic variations in synchrotron opacity (Epstein & Geller (1977);

(f) synchrotron or curvature radiation from electrons gyrating in a fixed dipole field (Milgrom & Bahcall 1978, Sanders & Da Costa 1978, Bachall & Milgrom 1980);

(g) various kinematic illusions caused by the finite signal propagation time (Rees 1966, 1967, Cavaliere et al. 1971).

"g" above is the "Illusion" solution. While they give it the best evaluation they also give considerable objections to it.


(c) To produce the observed superluminal motion, the motion must be closely aligned with a narrow cone along the line of sight which has an a priori probability of 1 percent (1/2); yet about half of all compact sources show evidence for superluminal motion, either from the VLBI observations or, less directly, but for a much larger sample, from the flux density variations.

I found the following comment most interesting since it was Quasar ejecta that we were discussing before.

Note:In the quote above there is a gamma symbol after the (1/2 Gamma) but it didn't cut and paste.

It is unlikely that this effect can be important in normal quasars, as the line and continuum intensities are typically comparable, and there is no evidence that the line emission in quasars contains a significant blue shift.

It appears that the "Illusion" and several other approaches can answer some observations but it also appears that the issue is far from a slam dunk for Relativity.

Further it appears this issue about blue shift which I raised is in fact a major concern which was poo pooed here.

I have run across the following paper which shows a superluminal object within our galaxy.

In the paper that you gave the link, it is said that the velocities of the objects are 92% of c.
Is this superluminal?
I thought, and correct me if I am wrong, that superluminal is faster than light.

1100f,

In the paper that you gave the link, it is said that the velocities of the objects are 92% of c.
Is this superluminal?
I thought, and correct me if I am wrong, that superluminal is faster than light.

ANS: You are correct. But the 92% is if it is corrected using the relavistic illusion explanation. The paper shows that as having a 1% likelyhood and in quasars fails to show the blue shift.