Demand for any of N assets can influence every other price, generating N^2 cross-impact slopes. Which interactions are determined by economic first principles and which reflect investor behavior? Using no arbitrage alone—without needing to specify a particular equilibrium—a new "Irrelevance...

We develop a tractable model to study how asset concentration among a few large investors impacts asset prices and liquidity. Consistent with existing empirical evidence: (i) greater concentration is associated with higher volatility and returns, and (ii) large investors’ turnover...

This study examines currency competition between a centrally managed currency, the Dollar, and a rigid-supply alternative, Bitcoin, focusing on the role of monetary policy. Using theoretical modeling and laboratory experiments, we show that proportional transfers, modeled as interest on Dollar...

Regulating externalities is a major challenge when economic agents face uncertainty and disagreement. Traditional Pigouvian and Coasean approaches often struggle because they require either precise knowledge of externality costs or frictionless bargaining. We propose an "uncertainty-based regulation" (UBR) mechanism that...

Using a structural model, we estimate the liquidity multiplier of an interbank network and banks’ contributions to systemic risk. To provide payment services, banks hold reserves. Their equilibrium holdings can be strategic complements or substitutes. The former arises when payment...

We propose a theory of banking in which banks cannot perfectly control deposit flows. Facing uninsurable loan and deposit shocks, banks dynamically manage lending, wholesale funding, deposits, and equity. Deposits create value by lowering funding costs. However, when the bank...