Prove that the scattering operator is unitary
29688
Why are scattering matrices unitary?
28416
Show that $\partial_\nu T^{\mu\nu} = - j_\nu F^{\mu\nu}$
122213
Proving that if $\langle Ax,x\rangle =0$ for every $x$, then $A$ is the zero operator
49759
Proving that $i\hbar\frac{\partial}{\partial \mathbf{p}}$ is the operator of $\mathbf{x}$ in momentum space
18839
Proof about inner product space $\vert \langle x,y\rangle \vert=\Vert x \Vert\Vert y \Vert$
144104
Show that a positive operator on a complex Hilbert space is self-adjoint
118049
Show that $\mathbb{R}^{\mathbb{R}} = U_{e} \oplus U_{o}$
44371
Finding trace and determinant of linear operator
14867
How to interpret $\langle x|\hat Q|x'\rangle$ for a quantum mechanical operator $\hat Q$?
26125
Does the canonical commutation relation fix the form of the momentum operator?
59067
How to prove that if the expectation value of $A$ in any state is real, then $A$ is Hermitian?
31919
What can we say about the inner product $\langle f(t),f'(t) \rangle$?
146730
The adjoint of left exterior multiplication by $\xi$ for hodge star operator
117175
Proof that the 2-norm of orthogonal transformation of a matrix is invariant
80623
Must $S$ be a unitary matrix?
44016
Proof that the One-Dimensional Simple Harmonic Oscillator is Non-Degenerate?
15231
Invariance of a maximally entangled state under unitary operation $U \otimes U^\dagger$