We show that debt is sustainable at a competitive equilibrium based solely on the reputation for repayment; that is, even without collateral or legal sanctions available to creditors. In an incomplete asset market, when the rate of interest falls recurrently below the rate of growth of the...

We show that sovereign debt is unsustainable if debt contracts are not supported by direct sanctions and default carries only a ban from ever borrowing in financial markets even in the presence of uninsurable risks and time-varying interest rate. This extension of Bulow and Rogoff, 1989 requires...

We analyze optimal monetary policy under commitment in an economy with uninsurable idiosyncratic risk, long-term nominal bonds and costly inflation. Our model features two transmission channels of monetary policy: a Fisher channel, arising from the impact of inflation on the initial price of...

We model the super-replication of payoffs linked to a country's GDP as a stochastic linear program on a discrete time and state-space scenario tree to price GDP-linked bonds. As a by-product of the model we obtain a hedging portfolio. Using linear programming duality we compute also the risk...

We model the super-replication of payoffs linked to a country's GDP as a stochastic linear program on a discrete time and state-space scenario tree to price GDP-linked bonds. As a byproduct of the model, we obtain a hedging portfolio. Using linear programming duality we also compute the risk...

We show that in a New Keynesian model with household heterogeneity, fiscal policy can be a perfect substitute for monetary policy: three simple conditions for consumption taxes, labor taxes, and the government debt level are sufficient to induce the same consumption and labor supply of each...

In HANK, we show that fiscal policy is an appropriate macroeconomic stabilization tool at the ZLB. Fiscal policy achieves the same macroeconomic aggregates and the same welfare as hypothetically unconstrained monetary policy by replicating its transmission mechanism. Consumption taxes and labor...