Why should I be?
I just looked him up. He died in 2014, and his last novel contribution to science was back in the 1970s. He was a critic of the big bang theory, basing his criticism on his hypothesis that the red-shifts of some distant galaxies (quasars) might have intrinsic causes, rather than being caused by the expansion of the universe. Fred Hoyle, of steady state theory fame, was apparently a bit of fan for while.
Arp was originally an astronomer, but over time he became more and more focussed on his single idea. His findings were initially peer-reviewed and discussed extensively at scientific conferences. When they did not find favour with his colleagues, he was not deterred, but continued to pursue the same research. As this was unproductive, his telescope time was reduced.After a while, he refused to submit the normal proposals for telescope observation time, then he chose to retire early. This was in the 1980s. Since then, our observational abilities have increased enormously, and there has been reams of evidence to show that the universe is expanding. At least one study tested Arp's theory and found that it didn't stack up, though one response argued that the study might actually have shown a small effect in the direction supporting Arp's views. As if often the case in pseudoscience, this borderline effect has been seized on by some who insist that it shows that Arp was right and most of modern astrophysics is wrong.
The claim that Arp's ideas were suppressed is nonsense, as they were initially treated with respect and re-examined in 2006. No doubt future observations will tend to either confirm or further refute Arp's theory. In other words, business as usual in science.
Not my doing. When you quote a post it does not include quoted material from that post, by default. You can still manually cut and paste, though.