" Sean Bowe, an engineer and cryptographer at Electric Coin Company (ECC), has discovered a technique for creating practical, scalable and trustless cryptographic proving systems, ending an almost decade-long pursuit by the cryptography community.
It’s called Halo. A paper authored by ECC employees Sean Bowe, Daira Hopwood and Jack Grigg is available here. An implementation that recursively demonstrates the proof-of-work of a Bitcoin block hash is also under development.
Halo achieves practical zero-knowledge recursive proof composition without the need for a trusted setup.
Recursive proof composition holds the potential for compressing unlimited amounts of computation, creating auditable distributed systems, building highly scalable blockchains and protecting privacy for all of humanity. The concept is a proof that verifies the correctness of another instance of itself, allowing any amount of computational effort and data to produce a short proof that can be checked quickly.
Sean’s discovery involves “nested amortization”— repeatedly collapsing multiple instances of hard problems together over cycles of elliptic curves so that computational proofs can be used to reason about themselves efficiently, which eliminates the need for a trusted setup."