In mathematics, sum of all natural number is infinity.
but Ramanujan suggests whole new definition of summation.
"The sum of $n$ is $-1/12$" what so called Ramanujan Summation.
First he find the sum, only Hardy recognized the value of the summation.
And also in quantum mechanics(I know), Ramanujan summation is very important.
Question. What is the value of Ramanujan summation in quantum mechanics?