Market Design for a Blockchain Based Financial System

We develop a theory of long-run equilibrium in blockchain-based financial systems. Our theory elucidates the key market design features that separate proof of work and proof of stake approaches in the long run. Under proof of work, wasteful computation is used to secure the system, and users' utility in equilibrium is determined by the threat of a fork. Under proof of stake, by contrast, users' utility in equilibrium is generally above the fork threat level because custodians can use relational contracts to incentivize a higher quality of service. Relational contracts under proof of stake rely only on local institutions-but combining them with cryptography can create a platform for formal global contracts.