Graphchain: A blockchain-free scalable decentralised ledger

Blockchain-based replicated ledgers, pioneered in Bitcoin, are effective against double spending, but inherently attract centralised mining pools and incompressible transaction delays. We propose a framework that forgoes blockchains, building a decentralised ledger as a self-scaling graph of cross-verifying transactions. New transactions validate prior ones, forming a thin graph secured by a cumulative proof-of-work mechanism giving fair and predictable rewards for each participant. We exhibit rapid confirmation of new transactions, even across a large network affected by latency. We also show, both theoretically and experimentally, a strong convergence property: that any valid transaction entering the system quickly become enshrined in the ancestry of all future transactions.