I tried searching this, but there are so many replies on each topic that I could not go through them.
Many years ago I read about Halton Arp's researches on the relation between quasars and irregular (peculiar?) galaxies. I thought that the 2DF surveys had refuted his claims about this connection.
But he also claimed that there was a periodicity in red shifts, and that they are not distributed randomly, and my recent reading indicates that this periodicity is still revealed in the latest galactic surveys.
Is this correct, and is there any explanation? It certainly makes one wonder about the redshift-velocity relationship. Perhaps there are ripple effects left over from the inflation era, that cause the expansion of space to occur in waves. (just a crazy conjecture).
Edit afterthought: If this was the case, then presumably the observed increase in expansion rate is because we are on the crest of the next wave.
Thanks for your reply, but my reading of Wiki is that Arp's active galaxy-quasar connection has been refuted, but not the redshift quantisation.
On redshifts, Wiki just says that is is not accepted by most astronomers. This us understandable as it is contrary to the current big-bang paradigm (hate that word). Wiki does not provide any scientific references refuting the redshift quantisation, and I cannot find any though Google. Besides, it is not just Arp. There are many other reports of it by other astronomers, the most recent I could find being 2008. Here are a couple.
Given the size of the surveys already done I would think that if redshift quantization were a thing the results would be stronger.
But there still is the question so more data is needed.
When the smart folks figure it out then we will know with some confidence one way or the other. Right now the consensus over the water cooler is that the redshift quantization is not favorably viewed but some new and interesting science may be on the way.
I wouldn't hold out much hope that redshift quantization will significantly derail the standard cosmological model as some of its fringe supporters hope. Right now the extraordinary level of data required to support the hypothesis is missing and none appear on the horizon.
Just thought up a better explanation. I am sure you are all familiar with the inflating balloon analogy to explain how everything moves away from everything else in the expansion. Well, maybe God has to pause to take breath before each puff into the balloon.