Recent content by Clifford Williams

My professor's solution is as follows: It relies on the identity \begin{align*} [\partial f(x,y)/\partial x] &= [\partial f(y)/\partial x]*[\partial f(x)/\partial x] \end{align*} to get from the penultimate line to the last line, however this is an identity I am neither familiar nor comfortable...

The problem was delivered exactly as phrased in the "Homework Statement": "Evaluate the commutator [𝑥(𝜕/𝜕𝑦), 𝑦(𝜕/𝜕𝑥)] by applying the operators to an arbitrary function 𝑓(𝑥,𝑦)." That feeling that you're missing something? That's exactly where I've been all day...

I checked a specific function, but I picked the function f(x) = x^2 +y^2, and my prof replied that "that's not a single valued function so it won't work, remember the postulates!" But even when I plug in single valued functions s.a. y=x-x^3, the commutator is not 0... My professor's solution...

Hello, In QM class this morning my Prof claimed that the commutator [𝑥(𝜕/𝜕𝑦), 𝑦(𝜕/𝜕𝑥)] = 0. However, my classmate and I arrived at x(d/dx) - y(d/dy). Can someone explain how (or if) our professor is correct?