Bound states in gauge theories\, from Q ED to QCD DTSTART;VALUE=DATE-TIME:20150305T090000Z DTEND;VALUE=DATE-TIME:20150313T110000Z DTSTAMP;VALUE=DATE-TIME:20241108T113640Z UID:indico-event-3507@indico.gsi.de DESCRIPTION:Abstract:\n\nPerturbative methods allow accurate calculations of QED bound states (atoms). Hadrons have atom-like features\, even though their quark and gluon constituents are highly relativistic and confined. The possibility that analytic Hamiltonian methods may be useful also for Q CD bound states merits careful attention.\n\nThe first lecture will be an overview of the motivations\, challenges and status of a Hamiltonian appro ach to gauge theory bound states. There is a tantalizing possibility that confinement is described by a classical gauge field (Born approximation)\, with loop corrections being perturbatively calculable. The A^0 potential of mesons is linear when the boundary condition on the homogeneous solutio ns of Gauss’ law is fixed by \\Lambda_{QCD}.\n\nBound states are spatial ly extended objects which transform non-trivially under boosts (c.f. the c lassical Lorentz contraction). Relativistic dynamics involves pair creatio n\, giving sea quark distributions. The Born level bound states also featu re parton - hadron duality. Scattering amplitudes are defined using the bo und states as zeroth order “in” and “out” states of the perturbati ve expansion.\n\nPrevious lecture notes can be found at http://arxiv.org/a bs/1402.5005 and a summary of results at http://arxiv.org/abs/1409.4703 .\ n\nhttps://indico.gsi.de/event/3507/ LOCATION:GSI Lecture Hall KBW URL:https://indico.gsi.de/event/3507/ END:VEVENT END:VCALENDAR