> (since fraud proofs are still not a solved problem?)

IMO they are. See https://github.com/ethereum/research/wiki/A-note-on-data-availability-and-erasure-coding

But you’d be right to say that it’s still theoretical and not yet implemented in a live network.

Source and More information: > (since fraud proofs are still not a solved problem?)

Author: Vitalik Buterin