Proof of Identity Sidechain Proposals
"randomly selected scientists" - randomly selected by whom? And will you have scientists in every city across the world? And how will they get paid?

Ideas like that are practically impossible, and if you remember how PGP key signing parties ended up you'll understand why nobody is pursuing it.

The way Identifi is doing trust and reputation is one way to solve this. The other way is BIP75, which could be used to present a certificate signed by some certificate authority mutually accepted between you and the other parties. This article goes into some detail about that.