Results 181 to 190 of about 198,578 (218)

Cascade model: A solvable field theory

Physical Review D, 1992
A fully solvable quantum theory in which the spectrum of scattering states shifts with the strength of the interaction is presented. Inelastic processes in which two particles go into three are obtained in this cascade model. By using the formalism of analytic continuation of the state spaces, resonances and redundant poles are identified.
, Chiu, , Sudarshan, , Bhamathi
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Vacuum instability for model field theories

Physical Review C, 1987
The perturbative vacuum for models in which fermions are coupled to scalar bosons and contain no derivative coupling for the scalar is shown to be unstable at the one-loop level. The instability is due to fluctuations at a sufficiently short-distance scale and is caused by the fermion loop contributions.
, Cohen, , Banerjee, , Ren
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The model theory of chain-closed fields

Journal of Symbolic Logic, 1988
The notion of a higher level ordering is a generalization of the usual notion of an order introduced by Becker in the study of sums of even powers in a field; see [1] for a general reference. A precise definition of an ordering of level 2n (level n in the terminology of [1]) is given in Definition 1.1(II) below.In [1] Becker worked out the extension ...
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Recoil Model in Quantum Field Theory

Physical Review, 1962
The static-source model is generalized to allow for the recoils and the mutual degrees of freedom of the source'' particles by adding to the Hamiltonian corresponding to the field and its sources the nonrelativistic Hamiltonian for the motion of the heavier particles. The resulting system can be quantized.
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Rotationally-Symmetric Model Field Theories

Journal of Mathematical Physics, 1965
A class of highly symmetric ,nonrelativistic, Euclidean invariant, model scalar field theories are examined assuming the existence of field and momentum operators that satisfy the canonical commutation relations (CCR). The high degree of symmetry that we assume permits explicit determination of every relevant CCR representation.
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The model theory of ordered differential fields

Journal of Symbolic Logic, 1978
In this paper, we show that the theory of ordered differential fields has a model completion. We also show that any real differential field, finitely generated over the rational numbers, is isomorphic to some field of real meromorphic functions. In the last section of this paper, we combine these two results and discuss the problem of deciding if a ...
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On the Model Theory of Function Fields

2022
We study the results of Duret [6] which discuss the first-order rigidity for function fields of curves over algebraically closed fields. To do so, we apply the definability of genus, as well as definability of the field of constants, results of Duret [5]. These are the focus of Chapter 3.
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Diffeomorphism cohomology in quantum-field-theory models

Physical Review D, 1988
We show that the cohomology of the Becchi-Rouet-Stora diffeomorphism operator on the integrated functions in ${\mathrm{R}}^{d}$ can be easily computed as a series whose terms contain the cohomology elements of the same operator on the unintegrated functions.
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Relativistic Model Field Theory

Physical Review, 1964
A relativistic generalization of the Lee model is constructed and solved in the first sector. The solubility is achieved with an indefinite metric and a redefinition of antiparticle operators, which amounts to a selection rule prohibiting pair creation. The renormalization of the Vparticle results in three dressed states, one of which is a ghost.
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A soluble model in field theory

Il Nuovo Cimento, 1960
A generalization of the Lee model was previously given with the restriction that the free and complete Hamiltonians possess the same stable one particle states. The model is applied to the calculation of unstable particle production and decay without separating the two processes. The model predicts bound state production for suitable cut-off functions.
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