New Particle Physics
Data from the Large Hadron Collider hints at things not fully explainable with extant physics. It's exciting to see people moving in that direction.
However, it's a lot less earthshaking if one already knows that matter and energy are just two phases of the same thing and all the forces really do connect. Getting enough detail to start building technology on it has perks, but botches at that level can make a nuclear explosion look like a firecracker. Things like "oops we cracked the planet's crust" and "uh, we seem to be halfway across the galaxy from where we were." I'm not confident of humanity's ability to handle that level of tech safely, since it can't handle current levels safely; but it's still very interesting to watch them trying to put the puzzle together.
However, it's a lot less earthshaking if one already knows that matter and energy are just two phases of the same thing and all the forces really do connect. Getting enough detail to start building technology on it has perks, but botches at that level can make a nuclear explosion look like a firecracker. Things like "oops we cracked the planet's crust" and "uh, we seem to be halfway across the galaxy from where we were." I'm not confident of humanity's ability to handle that level of tech safely, since it can't handle current levels safely; but it's still very interesting to watch them trying to put the puzzle together.