1998/05/23 by Ralf Pantfoerder, Pantfoerder, Ralf
Mathematics · Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Mathematics and Applications #Particle physics theoretical and experimental studies #Quantum and Classical Electrodynamics #Scientific Research and Discoveries #hep-ph
paper · pdf · doi:10.48550/arxiv.hep-ph/9805434
PhD thesis, 2+135 pages, private address given on title page, PLEASE DO NOT SEND MAIL OR EMAIL TO THE INSTITUTE
arxiv created 1998/05/23 · openalex publication_date 1998/05/23 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
All derivations of the GDH sum rule are presented and discussed in detail, focussing particularly on the validity of the underlying assumptions. Several tests of the sum rule within perturbative models are reviewed. Various possible sources of modifications of the sum rule are examined. With respect to the current-algebra derivation, the crucial role of the infinite-momentum limit is pointed out. A derivation is presented that exhibits the infinite-momentum limit as its last step, opening the prospect of studying its legitimacy within perturbative models. Adopting the Weinberg-Salam model as a testing ground, it is shown that a modification due to an anomalous charge-density commutator is remedied owing to the infinite-momentum limit. This finding is confirmed upon considering t-channel exchange of axial-vector mesons. Several other aspects of possible sources of modifications are investigated. Evolving the GDH sum rule to non-zero photon virtualities Q2, it is argued that different generalizations of the GDH integral, which coincide both at Q2=0 and at large Q2, may considerably deviate from one another at intermediate Q2. The limits Q2→0 and Q2→∞ are investigated beyond leading terms. The contribution of the pion-nucleon final state to inclusive electroproduction is analyzed.