Brian Greene has a new video out today, of himself talking to Edward Witten, mainly about string theory. Pretty much the usual decades-old hype, with nothing even slightly different than what a similar conversation would have consisted of 20 years ago.
Of historical and psychological interest, Witten explains that when the anthropic landscape nonsense arrived, it made him uncomfortable and unhappy:
I was very upset. It really got me disturbed. First of all, well, as a physicist, I wanted to explain the masses and lifetimes of the elementary particles and other properties, rather than accepting the fact that they depended upon the choice of a classical solution. Literally, it made me very unhappy for years. I made my peace with it because I had no alternative. So I made my peace with it by accepting the fact that the universe wasn’t created for our convenience and understanding it…
So I accepted that. I came to accept that, I would say, by now almost 20 years ago, roughly 20 years ago. And I’ve had a more peaceful life since then…
At the time I saw the “landscape” as something that would finally cause leaders of the field like Witten to admit that string theory wasn’t working and to hopefully move on to something else more promising. Surely he would not follow Susskind and some others down this obviously unscientific path. He explains here that facing the failure of his dreams “made me very unhappy for years”. He could have admitted failure, but that would lead to ongoing unhappiness. If he wanted to avoid admitting failure, he had no alternative.
String theory and string theorists like Greene and Witten more than 20 years ago reached a dead end. They were much younger then and one could have imagined a new beginning of a more promising direction. At this point though, any hope of that is long gone. They’ve long ago decided that they had “no alternative” but to spend the rest of their days repeating the same hype that had inspired them in their youth.
Greene does at one point refer to critiques of string theory, while dismissing these with the rather nasty ad hominem characterization of “the chatter of people who may have other agendas”. Unfortunately this conversation is largely the chatter of two people with a shared agenda, that of continuing to prop up a failed idea they are heavily invested in.