He might have been a “top physicist”, but it appears he has long since started phoning it in.

See the link to Aaronsons blog elsewhere in the thread for an example of the kind of drivel Kaku puts out, and why he shouldn’t be taken seriously.

string field theory is a a "field" of physics which is entirely theoretical and has no experiment data to back it up.... hard to imagine how even the top person in that field would be a top physicist given the large number of top physicists who are doing useful stuff like LIGO, CERN, etc.