The Gerasimov-Drell-Hearn sum rule
and the infinite-momentum limit
R. Pantförder - H. Rollnik - W. Pfeil
Physikalisches Institut der Universität Bonn,
Nußallee 12, D-53115 Bonn, Germany
(e-mail: pantfoer@thew01.physik.uni-bonn.de)
Received: 25 March 1997
Abstract
We study the current-algebra approach to the Gerasimov-Drell-Hearn sum rule,
paying particular attention to the infinite-momentum limit.
Employing the 
Weinberg-Salam model of weak interactions
as a testing ground, we find that the legitimacy of the
infinite-momentum limit is intimately
connected with the validity of the naive equal-times algebra of electric
charge densities.
Our results considerably reduce the reliability of a recently
proposed modification of the Gerasimov-Drell-Hearn sum rule,
originating from an anomalous charge-density algebra.
Copyright Springer-Verlag
