> I wanted to find not-so-popular companies working on hard tech, long term problems You won't find many. By definition what you're describing is incredibly ex

> I wanted to find not-so-popular companies working on hard tech, long term problems You won't find many. By definition what you're describing is incredibly expensive and without an immediate return. So the only groups that can afford work on these kinds of problems are academics, big companies with large R&D budgets or organizations like NASA or CERN. Any small company that attempts this will just go broke very quickly.