We study the possible bound states of the KK¯ system in the Bethe-Salpeter formalism in the
ladder and instantaneous approximations. We find that the bound states exist. However …

The recent observation of a positronium molecule (e− e+ e− e+) by Cassidy and Mills (DB
Cassidy and AP Mills 2007 Nature (London) 449 195) raises interest in other (fermionic) …

A generalization of the scalar Yukawa model to include many'flavors' of scalar particles and
antiparticles is considered. The variational method within the Hamiltonian formalism of …

We use the variational method within the Hamiltonian formalism of quantum field theory to
derive relativistic two-,(four)-, and (six)-body wave equations for scalar particles interacting …

We use the Hamiltonian formalism of quantum field theory and the variational basis-state
method to derive relativistic three-body wave equations for scalar particles interacting via a …

The variational method in a reformulated Hamiltonian formalism of quantum
electrodynamics (QED) is used to derive relativistic wave equations for systems consisting of …

The variational method within the Hamiltonian formalism of quantum field theory is used to
derive relativistic n-body wave equations for scalar particles and antiparticles. The equations …

We consider nonlinear-mediating-field generalizations of the Wick–Cutkosky model. Using
an iterative approach and eliminating the mediating field by means of the covariant Green's …

The Hamiltonian formalism of quantum field theory and the variational methods in a
reformulated model have been used to investigate the influence of retardation effects or …

We study the interparticle potentials for few-particle systems in a scalar theory with a
nonlinear mediating field of the Higgs type. We use the variational method, in a reformulated …