For a consumer to borrow funds the nominal rate is negative? Where have you seen this? I'd like to see a citation. The reason this rate cannot be negative is t

For a consumer to borrow funds the nominal rate is negative? Where have you seen this? I'd like to see a citation. The reason this rate cannot be negative is that demand will immediately fill it up and use it for arbitrage (shove the money under a mattress and pay back the loan later) before it can become negative.