This list is hopelessly optimistic but that's part of the fun. If only one of these happen I'll consider this list a success. I remember in 2010 I was sure we'd have full self-driving in all new cars by now since Google had the working prototype, how wrong that was! I also worked on LIGO and knew from the inside there was a good chance of a detection and that it would be mainstream news if it came true, which it did.

Here's my list of things that are theoretically (but barely) reachable by 2020:

- Fully programmable quantum computers. Google finally achieved "quantum supremacy", which isn't useful by itself, but a milestone showing progress. QCs will matter more for simulating quantum dynamics than all the encryption stuff.

- The first human landing on Mars. SpaceX seems to be good at setting aggressive targets, missing them, but then hitting them eventually. At the time of this writing they claim the first manned mission will be in 2024, so likely it will happen ~2028.

- A working prototype of an energy-positive fusion reactor. There was some good progress by the team at MIT by using a new type of superconducting tape that can handle significantly stronger magnetic fields.