I love Roger Penrose, not just because he knows a lot about science, but mainly because he bluntly states that things can be wrong. einstein and schrodinger called quantum theory incomplete, but Roger just call it wrong instead of mincing words.
I read one of his books years ago, and it talked about the red shift seen in the light of stars. But the way he explained it didn't click with me. Instead, when he described the empty voids between the stars, I felt they would not be empty, but instead the place where supermassive black holes were situated. It was like a bunch of soap bubbles, with a black hole at the center of each of those bubbles. And to me, these massive pulls of gravity would slow light down as it traveled between them, causing it to red-shift.
So was Roger Penrose wrong? Maybe, maybe not. But who am I to call out a Nobel prize winner?