Some Simple Bitcoin Economics

Abstract

In an endowment economy, we analyze coexistence and competition between traditional fiat money (Dollar) and cryptocurrency (Bitcoin). Agents can trade consumption goods in either currency or hold on to currency for speculative purposes. A central bank ensures a Dollar inflation target, while Bitcoin mining is decentralized via proof-of-work. We analyze Bitcoin price evolution and interaction between the Bitcoin price and monetary policy which targets the Dollar. We obtain a fundamental pricing equation, which in its simplest form implies that Bitcoin prices form a martingale. We derive conditions, under which Bitcoin speculation cannot happen, and the fundamental pricing equation must hold. We explicitly construct examples for equilibria

Keywords: Cryptocurrency, Bitcoin, Currency Competition, Exchange rates, Indeterminacy

JEL Classification: D50, E42, E40, E50