In April Haruhiko Kuroda, the governor of the BoJ, had said the bank would encourage further falls in nominal interest rates.

4月，日本央行(BOJ)行长黑田东彦宣称，日本央行将支持名义利率的进一步下跌。

It applies when nominal interest rates or risk-free returns exceed nominal growth.

它适用于名义利率或无风险回报超过名义增长率的情况。

Indeed, the idea that nominal interest rates cannot fall below zero is a reason why central banks have adopted policies such as quantitative easing.

确实，名义利率不能低于零是央行实行比如量化宽松这样的政策的原因。