Anderson orthogonality theorem

The Anderson orthogonality theorem is a theorem in physics by the physicist P. W. Anderson. The Anderson orthogonality theorem is a theorem in physics by the physicist P. W. Anderson. It relates to the introduction of a magnetic impurity in a metal. When a magnetic impurity is introduced into a metal, the conduction electrons will tend to screen the potential V ( r ) {displaystyle V(r)} that the impurity creates. The N-electron ground state for the system when V ( r ) = 0 {displaystyle V(r)=0} , which corresponds to the absence of the impurity and V ( r ) ≠ 0 {displaystyle V(r) eq 0} , which corresponds to the introduction of the impurity are orthogonal in the thermodynamic limit N → ∞ {displaystyle N o infty } .