Halton Arp was a controversial kinda guy. He had lots of problems with cosmology. He had some interesting and wrong ideas for sure.
But he also claimed that there was a periodicity in red shifts ...
Wiki tells us Arp's data were reviewed many times and found no such effect.
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).
Ohh, I like the crazy conjecture. A sort of
baryon acoustic oscillations (BAO) like thing from the plasma but instead in the
inflaton field itself.
That is quite good. Have a go-bag ready in case Stockholm calls.
Eschew obfuscation. Habituate elucidation.