The physical meaning of ${\rm Tr}()$ in quantum mechanics
30037
What information does the trace of a matrix give?
41332
Significance of the term "diffusion" in Grover's diffusion operator
108657
Cross product of the quantum mechanical operators $\textbf{p}$ and $\textbf{A}$
156712
Geometrical or Physical significance (interpretation) of the inner-product $\langle A,B \rangle := Trace (AB^t)$ over $M_n(\mathbb R)$
138832
Expansion coefficients of an arbitrary state in the Hilbert space of one-particle states
90475
Coordinate-free proof of $\operatorname{Tr}(AB)=\operatorname{Tr}(BA)$?
59004
Why does time evolution operator have the form $U(t) = e^{-itH}$?
130497
Understanding Dirac's notation
14867
How to interpret $\langle x|\hat Q|x'\rangle$ for a quantum mechanical operator $\hat Q$?
128932
Is my expansion of the state $| x \rangle$ correct?
58072
The formal solution of the time-dependent Schrödinger equation
156863
Uncertainty Principle for a Totally Localized Particle
45061
Physical interpretation of $Q^i = \partial _\nu T^{i \nu}$
11529
What is the quantum mechanical explanation of the octet rule?
55231
Is there a simple way of finding the eigenstates of the creation and annihilation operator in QM?
34021
What is the physical meaning of a "complete" Hilbert space in QM?
36262
Linear algebra for quantum physics