Is it true that physicists are losing their hope in string theory?The answer is obviously yes, but he refuses to admit it.
Greene's answer is amusingly weak. He is unable to point to any theoretical or experiment progress in string theory. He just babbles.
He starts by getting a drink of water, emphatically saying the answer is no, and claiming that the string theory critics need psychotherapy!
He goes on to defend the multiverse, even tho that was not really the question. He says string theory does not require a multiverse, but he argues for the multiverse, as that were essential to his belief in string theory.
He implies that only a narrow-minded person would only believe in one universe. He admits that it is desirable to have physical evidence for physical theories, but says that evidence for part of a theory (ie, one universe) can be taken to enhance a belief in other parts (ie, other universes.
He ends by saying that the state of the field is one of excitment.
Watch the above video from 42:00 to 46:00 if you think that I have distorted him.
If I knew nothing about string theory, I would say that this is a con man promoting goofy ideas that no one could believe. If I watched the rest of the video, I would see that he undertands a lot of physics, and is good at explaining textbook physics, and I would be very confused.
Dr. Bee's latest video says that string theorists have given up on their original goals, leaving an overhyped research program. The multiverse is so silly it is not even science. She challenges a lot of modern theoretical physics as too speculative to be worthwhile.