Four important questions around long-term interest rates

Four questions , which have been the subject of much debate in the recent economic literature, are key to any discussion o n the trajectory of long-term interest rates. Why are long-term interest rates low? Is it because of excess savings or expansionary monetary policies? What effect do low interest rates have on financial intermediaries? Do they weaken them ( by reducing their income) or strengthen them ( by reducing borrower/issuer defaults)? Does a long period of low interest rates lift inflation or drive it lower instead (this is the neo- Fisheri an theory )? The required return on capital has not tracked the fall in risk-free interest rates, which has eliminated the effect of the expansionary monetary policy on the savings and investment equilibrium. Is this because risk premia have risen?