> Speaking of dead fields... I know many postdocs who come from physics into ML because many areas of theoretical physics just don't seem to be going anywhere anymore. Not a good sign!
I do not necessarily agree with the notion that many fields are dead --- they could just be "resting" until some paradigm-shifting idea comes along, at which point they may spring back to life --- but I do agree with your observation that many people with PhDs have to move out of science or research. There simply are too few jobs available in research, so many people with PhDs eventually transition to non-scientific or non-research roles as their opportunities to continue doing research diminish. It's just economics. I do have to agree that it is frustrating how slow progress can be while conducting research, but I think people leave science more often due to the lack of job opportunities than the lack of progress in their research.
As an undergrad, I asked if I should take a control theory class, and was told it was a dead field.
It has become pretty important, since: all the quad copter controllers run it, and it is in network flow management protocols. I would have used it, unlike most of what I did study.
I do not necessarily agree with the notion that many fields are dead --- they could just be "resting" until some paradigm-shifting idea comes along, at which point they may spring back to life --- but I do agree with your observation that many people with PhDs have to move out of science or research. There simply are too few jobs available in research, so many people with PhDs eventually transition to non-scientific or non-research roles as their opportunities to continue doing research diminish. It's just economics. I do have to agree that it is frustrating how slow progress can be while conducting research, but I think people leave science more often due to the lack of job opportunities than the lack of progress in their research.