Unitary transformations with the unitary operators depending on projection operators

✍ Scribed by N. F. Stepanov

• Publisher: John Wiley and Sons
• Year: 1981
• Tongue: English
• Weight: 478 KB
• Volume: 19
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/qua.560190510

✦ Synopsis

Abstract

Unitary transformations of operators and variables are considered for those cases when a Hermitian operator in the expression U = exp (iS) explicitly depends on the projection operators. Some simple examples of such transformations are given and the equations obtained which define projectors (among special sets of them), thus bringing forth better estimations for upper and lower bounds. The unitary transformations are also applied to the reduced resolvent operator and equations are presented for the operators U that minimize the energy functional.