When the employees of Rolls-Royce Holdings Plc read that coronavirus lockdowns and home-working have ignited a technology boom, they could be forgiven for weeping. The company makes the jet engines that power large passenger jets, which is one of the most technically complex engineering tasks known to man. And yet, most of Rolls-Royce’s products are grounded right now because hardly ...

Ordinarily, a new medical treatment is approved only after at least one large-scale, randomised controlled trial shows it to be effective without being harmful. Yet at times — and notably during epidemics — evidence can mount that a treatment is safe and effective before we have that final evidence. We think this is the case with Covid-19 and convalescent plasma. ...

After a more than year-long review of its monetary policy strategy, the Federal Reserve has decided it will throw away the rule book and let inflation run higher and unemployment run lower before seeking to tighten financial conditions. To be clear, this change leaves the central bank pursuing an almost completely discretionary monetary policy, one where the risk is that ...