Recent content by safekhan

thanks, but how should I treat p.r term in the solution while differentiating with respect to (t,x,y,z)

Homework Statement [/b] The attempt at a solution[/b] I have done the first bit but don't know how to show that phi(r,t) is a solution to the equation of motion.

Thanks So for hermitian A= A(dager), but would u write (A^2)* = A*A* = A*(an* ket(n)) ...

it equals =an ket(n) than A(an ket(n)) = an A ket(n) = an (an ket (n))= an^2 ket(n) is that correct way to do it?

Relationship: it's a postulate of QM that every dynamical observable is represented by a linear hermitian operator. A*A ket(n) = ? but not sure what will be on the right hand side

Q: Using Dirac notation, show that if A is an observable associated with the operator A then the eigenvalues of A^2 are real and positive. Ans: I know how to prove hermitian operators eigenvalues are real: A ket(n) = an ket(n) bra(n) A ket(n) = an bra(n) ket(n) = an [bra(n) A ket(n)]* =...