| I can't speak to the merits (or lack thereof) of string theory. That's well beyond my physics knowledge. It must however be daunting to be a theoretical physicist right now. It seems like the field has been in a standstill for years. The advances in the 20th century were just eye-watering. The Standard Model is a mixed bag of stunningly accurate prediction (eg electron monopole moment [1]) vs the wildly inaccurate (eg the so-called "vacuum catastrophe" [2]). And there are so many unanswered questions, like nobody really seems to know what particle generations are or why they exist. Or that particle masses can't be derived from first principles (or that the math can't be solved, I'm honestly not sure). It seems like we have no intuition for a lot of this stuff because there's no analog in the real world. So we give names to things (eg color, spin) that are just abstract properties. Electromagnetism is tantalizingly simple. The strong nuclear force interacts with its own carrier particles so is far from simple. The mediating particles of the weak nuclear force were, I believe, the first evidence of the Higgs field (because they have mass) but again, not my speciality. But here's the interesting part (to me): the human systems surrounding it. When progress slows in a field, you'll find the tendency of people to coalesce around certain ideas that may border on dogma because careers are built on reputation and nobody wants to be "wrong". Likewise, string theory has a lot of investment in it. People have built careers on it. Nobody wants to throw that away. The LHC gave experimental evidence to the Higgs boson, which was one of its goals. It's also managed to disprove a lot of theories, which is useful. But it hasn't given any hint of where to go. There's already talk of a successor but nobody really knows what to look for so it's hard to imagine that'll go anywhere. So string theory seems to be like physics orthodoxy now. j[1]: https://cfp.physics.northwestern.edu/documents/PhysicsToday-... [2]: https://en.wikipedia.org/wiki/Cosmological_constant_problem |
The general public don't really understand where most physicists work. The largest subfield of Physics is really in condensed matter, where (depending on how you count it) somewhere like 30-50% of physicists work, and where there is plenty of interesting theory work. High energy physics is the next biggest subfield, but much of it is experimental, and then you get into "classical physics" like acoustics, optics, etc. Astrophysics is relatively smaller. There's also nuclear, plasma, fusion and then a whole host of interdisciplinary work like biophysics, materials science, etc. Especially with interdisciplinary work, people often do bits and pieces throughout their career, not everyone sticks strictly to a single subfield.
There's plenty of interesting theoretical physics work in pretty much all of these fields. Not everyone works on grand problems of the universe!