Host: Dr. Hubble, what exactly do we observe when we detect a galactic redshift which is received on Earth from a very distant galaxy?
Hubble: Well, the visible light spectrum of every galaxy is very similar to the visible light spectrum of the sun. Therefore, it is reasonable to assume that all galaxies are dominated by yellow dwarf stars like our Sun. Although the light received from very distant galaxies is quite faint, we can still recognize the unmistakable H and K dark absorption lines of absorbed calcium. The dark absorption lines of absorbed hydrogen and absorbed iron can also be recognized.
The entire absorption spectrum of each galaxy appears to have been shifted toward the red end of the radiation spectrum in the same manner as familiar Doppler velocity shifts in the local space of the Milky Way Galaxy. However, with galactic redshifts there are three very obvious and important exceptions. First, except for the “Local Group” of galaxies that are closest to the Earth, all more distant galactic light shifts are always displaced or shifted toward the red end of the normal rainbow-like spectrum of light. Please see Figure 14 and Chart 15. On the other hand, familiar Doppler velocity shifts in local Milky Way space, and light shifts received from the Local Group of galaxies, are randomly or indiscriminately displaced either toward the red end or toward the blue end of the visible light spectrum in seemingly equal numbers. Please see Figure 14A, Chart 15A, Figure 16, and Chart 17.
Second, all of the more distant displacements of galactic redshifts toward the red end of the radiation spectrum are of much greater magnitude than is the case with familiar local Doppler velocity redshifts. Please see Figure 18.
Third, and most importantly, the displacement of the dark absorption spectrum towards the red systematically increases with the increase of estimated distance of each galaxy from the Earth, and this correlation is approximately linear (one-to-one) in proportion. Please see Figure 19.
Host: Do you agree, Professor Dingle?
Dingle: Yes. But I might also add, that the observed magnitudes of galactic redshifts by themselves do not indicate anything other than what Dr. Hubble concluded in 1929 and 1931. In 1929, and again in 1931, Dr. Hubble merely concluded that galactic redshifts are observed to increase in magnitude in linear (one-to-one) proportion to the distance of their source galaxies from Earth. See Figures 7 and 18. By themselves, these increasing magnitudes of galactic redshifts do not indicate any cosmic motion or any systematic recession velocity of the galaxies. It is only if and when someone validly interprets (and thus demonstrates) them to be the same phenomenon as the familiar Doppler velocity redshifts in local Milky Way space that they could even possibly infer a velocity…let alone imply systematic recession velocities of the galaxies on a cosmic scale.
As George McVittie concluded in 1974, and I quote:
“Admittedly the nature of the displacements of [a galactic redshift’s] spectral lines is consistent with the view that they arise from a Doppler effect. But this does not prove that the displacements must be due to a Doppler [velocity] effect. The Doppler effect was only the simplest physical interpretation available for the redshift phenomenon in the spectra of galaxies, and it is surely for this reason that it has come to be accepted.”
On the other hand, if galactic redshifts are not the same phenomenon as familiar Doppler velocity shifts in local Milky Way space, then there is no empirical or other scientific basis upon which to infer or even suggest any motion of the galaxies on a cosmic scale, let alone that the universe is expanding. As I concluded in my 1961 treatise on the Doppler effect of light, and I quote:
“The whole phenomena known as ‘the expansion of the universe’ consists of deductions from this one principle…the Doppler velocity effect.
“It is doubtful if there is a serious rival to the Doppler velocity effect as the department of modern science in which the experimental basis is slightest in comparison with the theoretical structure raised on it…
“The whole phenomenon known as ‘the expansion of the universe’ consists of deductions from this one principle: [‘the Doppler Velocity effect of light’]. It would be fair to say that without it cosmology would scarcely exist as a scientific subject.”
Host: Dr. Eddington, you have remained silent up until now. What did you interpret the detected galactic redshifts to indicate?
Eddington: Hubble and Dingle are correct. What is actually observed is merely a shifting of the spectrum of the [galaxy] towards the red. In our local space, such a shift is commonly caused by the Doppler effect of a receding velocity, in the same way that the pitch of a receding whistle is lowered.
As I stated in my 1933 book, entitled The Expanding Universe, and I quote:
“The simple proportionality of speed to distance was first found by Hubble in 1929. The more distant [galaxies] have the bigger velocities; the results seem to agree very well with a linear law of increase, the velocity being simply proportional to the distance. The most striking feature is that the galaxies are almost unanimously running away from us. Their picture is the picture of an expanding universe.
“When Dr. Hubble hands over a key which he has picked up in intergalactic space, I am not among those who are going to turn it over and over unable to decide from the look of it whether it is good metal or base metal. The question for me is, will it unlock the door?” [In other words, what does it tell us?]
“For the above reasons, I think that we have no excuse for doubting the genuineness of the observed velocities.”
Hubble: I beg your pardon, Dr. Eddington, but I did not find a simple proportionality of galactic speed to distance in 1929 or any other time. The proportionality that we found was the magnitude of redshift to distance. Humason and I decided to use the local space Doppler velocity scale purely as a matter of convenience, as we have pointed out many times. We wanted to leave the interpretations and deductions to others, as to what our linear law of redshifts meant. In retrospect, I must admit it was an unfortunate mistake to use the local space velocity scale, because I have repeatedly been blamed for discovering the Expanding Universe. In fact, my considered conclusions during the late 1930s were directly to the contrary.
Host: Professor Dingle, do you have something to add?
Dingle: Yes. In his 1933 book, Dr. Eddington was automatically interpreting that such observed galactic redshifts indicate a Doppler velocity of the galaxies away from the Earth. On the contrary, his proposed “new linear law of increased Doppler velocity proportional to distance” merely begs the question: are galactic redshifts the same phenomenon of nature as the familiar Doppler velocity shifts in the Milky Way Galaxy?
Host: Why so, Professor Dingle? Why shouldn’t such an interpretation be automatic?
Dingle: Because of one simple, provable and undeniable fact that has seemed to have been overlooked by everyone. In the local space of the Milky Way Galaxy, Doppler velocity light shifts are not observed to be systematically proportional to any distance whatsoever. In the Milky Way galaxy there is absolutely no correlation between the magnitudes of Doppler velocity light shifts and the distance from the light source to the observer.
Host: Will you elaborate on these very interesting comments a little later on, Professor Dingle?
Dingle: Gladly, because they are the real key to our entire discussion.