Periodicity 会品-mn-E 式可"ea-o小-5u-w +r闲lr+n-st+a .'.(x+a),(x)are all solutions of the same hamiltonianPeriodicity   ( ), ( )are allsolutions of thesame hamiltonian. ( ) ( ) ( ) 2 ( ) ( ) ( ) 2 2 2 2 2 2 2 x a x V x x a E x a dx d m V x a x a E x a d x a d m                                   ( ) ( ) ( ) 2 2 2 2 V x x E x dx d m            