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Vacuum Structures in Hamiltonian Light-Front Dynamics

F. Coester·W. Polyzou
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Abstract

Hamiltonian light-front dynamics of quantum fields may provide a useful approach to systematic non-perturbative approximations to quantum field theories. We investigate inequivalent Hilbert-space representations of the light-front field algebra in which the stability group of the light-front is implemented by unitary transformations. The Hilbert space representation of states is generated by the operator algebra from the vacuum state. There is a large class of vacuum states besides the Fock vacuum which meet all the invariance requirements. The light-front Hamiltonian must annihilate the vacuum and have a positive spectrum. We exhibit relations of the Hamiltonian to the nontrivial vacuum structure.

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F. Coester, W. Polyzou. 1993-05-10. Vacuum Structures in Hamiltonian Light-Front Dynamics. https://doi.org/10.1007/bf02058099

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