Il Nuovo Cimento A (1965-1970)

, Volume 50, Issue 2, pp 193–210 | Cite as

Bound-state equation for quark-antiquark systems

  • R. Delbourgo
  • A. Salam
  • J. Strathdee


The Bethe-Salpeter equation for spinor quark-antiquark binding in the ladder approximation is studied in terms of projective variables. These variables exhibit the maximal symmetry of the problem as anO5 symmetry for special values of masses involved. The realistic Bethe-Salpeter equation is treated as corresponding to a brokenO5 symmetry situation. Among other advantages of this approach is that the continuum eigenvalue difficulties for the bound states encountered in other treatments seem obviated.


Wick Rotation Maximal Symmetry Spinor Case Ladder Approximation Particle Wave Function 
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Уравнение связанного состяяния для системы кварк-антикварк


В выражениях проективных переменных изучается уравнение Бете-Салпетера для спинорной кварк-антикварк связи в лестничном приближении. Эти переменные показываут максимальную симметрию проблемы, когда имеет местоO5 симметрия для специалянух величин масс. Реаляное уравнение Бете-Салпетера трактуется как ситуация, соответствуюцая нарушеннойO5 симметрии. Среди других преимушеств этого приближения следует отметитя, что, кажется, устраняются трудности непрепявнух собственных значений для связанных состояний, которые имеют место в других рассмотрениях.


Si studia in funzione delle variabili proiettive l’equazione di Bethe-Salpeter per il legame quark-antiquark spinoriale nell'approssimazione a gradini. Queste variabili presentano la massima simmetria del problema come simmetriaO5 per valori speciali delle masse coinvolte. Si tratta l'equazione di Bethe-Salpeter realistica come se corrispondesse ad una situazione di simmetriaO5 infranta. Uno dei vantaggi di questo accostamento è che le difficoltà dell'autovalore del continuo per gli stati legati incontrate in altri trattamenti sembrano ovviate.


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Copyright information

© Società Italiana di Fisica 1967

Authors and Affiliations

  • R. Delbourgo
    • 1
    • 2
  • A. Salam
    • 1
    • 2
  • J. Strathdee
    • 1
    • 2
  1. 1.International Atomic Energy AgencyInternational Centre for Theoretical PhysicsTrieste
  2. 2.Imperial CollegeLondon

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