We consider constructing a canonical quantum theory of the light-cone gauge ($A_-$=0) Schwinger model in the light-cone representation. Quantization conditions are obtained by requiring that translational generators $P_+$ and $P_-$ give rise to Heisenberg equations which, in a physical subspace, are consistant with the field equations. A consistent operator solution with residual gauge degrees of freedom is obtained by solving initial value problems on the light-cones. The construction allows a parton picture although we have a physical vacuum with nontrivial degeneracies in the theory.Comment: 19 pages, two ps figures, uses ptptex.sty and psfi

The process v+n-'>-p.-+p is studied by using the dual resonance model, in which the p.-p resonance recently observed by the CERN group is considered to lie on a Regge trajectory. Quantities corresponding to the vector current form factors are compared with the nucleon electro-magnetic form factors. Other quantities corresponding to the axial-vector current form factors are also examined. The two-peak resonance structure of the A 2 meson is explained from our model. § I. IntroductionAn enhancement m the reaction (1·1) has been found in the data of the CERN Heavy Liquid Bubble Chamber Group. 1 ) Such an enhancement would correspond to a "lepto-baryonic" resonance. 2 )The mass value is about 2 Ge V and tbe width is expected to be of the order lo-se V. 1 ) Hereafter we call this the T boson.The search for narrow resonances in the cross-section for process (1 ·1) is very difficult because of the poor energy resolution associated with the spread of the neutrino momentum distribution and the Fermi motion of the neutron within the nucleus. However, Yoshiki et al. 1 ) have measured the invariant-mass distribution of the (tCP) system, which can be done with a much better energy resolution, typically ±50 MeV.The centre-of-mass muon distribution is strongly peaked forward, then this excludes a spin zero effect. In this paper we shall assume J = 1 for the spin of the T boson as the next simple possibility.Our purpose is to study the process (1·1) from the viewpoint of the dual resonance model, in which the T boson is considered to lie on a Regge trajectory aT (s). In § 2, estimation of the coupling strength of the T boson is reviewed; its interaction is superweak. In § 3, invariant amplitudes for the process (1 ·1) are defined, and the pole-residues of the T boson appearing in each amplitude are calculated by using the Fierz identities. On the basis of § § 2 and 3, the amplitudes are given in § 4 by the Veneziano formulas. In particular, amplitudes corresponding to the vector current form factors in the V-A theory are compared with the nucleon electro-magnetic form factors, Other amplitudes correat Ernst Mayr

We continue McCartor and Robertson's recent demonstration of the indispensability of ghost fields in the light-cone gauge quantization of gauge fields. It is shown that the ghost fields are indispensable in deriving well-defined antiderivatives and in regularizing the most singular component of the gauge field propagator. To this end it is sufficient to confine ourselves to noninteracting abelian fields. Furthermore, to circumvent dealing with constrained systems, we construct the temporal gauge canonical formulation of the free electromagnetic field in auxiliary coordinatescosθ and x − plays the role of time. In so doing we can quantize the fields canonically without any constraints, unambiguously introduce "static ghost fields" as residual gauge degrees of freedom and construct the light-cone gauge solution in the light-cone representation by simply taking the light-cone limit (θ → π 4 ). As a by product we find that, with a suitable choice of vacuum, the Mandelstam-Leibbrandt form of the propagator can be derived in the θ = 0 case (the temporal gauge formulation in the equal-time representation).

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