β Scribed by Paul Federbush
No coin nor oath required. For personal study only.
A Feynman diagram that has three particle intermediate states in all channels is studied. Choosing special values of the masses, in particular taking infrared divergent terms as certain masses go to zero, we explicitly calculate the spectral functions in this limit. They are nonzero in all three regions.
π SIMILAR VOLUMES
## Abstract It is shown that there exist domains Ξ© β β^__N__^, which outside of some ball coincide with the strip β^__N__ β 1^ Γ (0, Ο) and for which the Dirichlet Laplacian β Ξ has eigenvalues within the subinterval (1, 4) of the essential spectrum (1, β).
A procedure is described for extracting the dominant behavior at high energies of individual Feynman diagrams. This procedure is illustrated by the calculation of several examples, and is applied to the summation of several classes of diagrams in the high energy limit. Although all the examples deal
## Abstract A realistic representation of an ensemble of interacting molecules (or atoms, or ions) requires a description that includes the following parameters: the electronic energy, E, the electronic density, Ο, the temperature, T, the free energy, ΞG, and the entropy, ΞS. It is, therefore, nece