112 citations · 425 across the 33 of their papers we have counts for
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Scattering Theory with Path Integrals
R. Rosenfelder
Starting from well-known expressions for the -matrix and its derivative in standard nonrelativistic potential scattering I rederive recent path-integral formulations due to Efim…
Path Integrals in Quantum Physics
R. Rosenfelder
These lectures are intended for graduate students who want to acquire a working knowledge of path integral methods in a wide variety of fields in physics. In general the presentati…
A New Path-Integral Representation of the -Matrix in Potential Scattering
J. Carron, R. Rosenfelder
We employ the method used by Barbashov and collaborators in Quantum Field Theory to derive a path-integral representation of the -matrix in nonrelativistic potential scattering…
Exact Path-Integral Representations for the -Matrix in Nonrelativistic Potential Scattering
R. Rosenfelder
Several path integral representations for the -matrix in nonrelativistic potential scattering are given which produce the complete Born series when expanded to all orders and th…
Variational Approximations in a Path-Integral Description of Potential Scattering
J. Carron, R. Rosenfelder
Using a recent path integral representation for the T-matrix in nonrelativistic potential scattering we investigate new variational approximations in this framework. By means of th…
Path Integrals for Potential Scattering
R. Rosenfelder
Two path integral representations for the -matrix in nonrelativistic potential scattering are derived and proved to produce the complete Born series when expanded to all orders.…
Structure function of a damped harmonic oscillator
R. Rosenfelder
Following the Caldeira-Leggett approach to describe dissipative quantum systems the structure function for a harmonic oscillator with Ohmic dissipation is evaluated by an analytic…
Coulomb Corrections to Elastic Electron-Proton Scattering and the Proton Charge Radius
R. Rosenfelder
Recent values of the proton charge radius derived from the Lamb shift in electronic hydrogen tend to be larger than those from electron scattering. Therefore low-momentum-transfer…
Variational treatment of quenched QED using the worldline technique
A. W. Schreiber, C. Alexandrou, R. Rosenfelder
There has been growing interest in studying the behaviour of QED in its strong coupling limit. The reason for this is not only that it serves as a simple prototype gauge theory for…
Variational Field Theoretic Approach to Relativistic Scattering
C. Alexandrou, R. Rosenfelder, A. W. Schreiber
Nonperturbative polaron variational methods are applied, within the so-called particle or worldline representation of relativistic field theory, to study scattering in the context…
First Order Variational Calculation of Form Factor in a Scalar Nucleon--Meson Theory
A. W. Schreiber, R. Rosenfelder
We investigate a relativistic quantum field theory in the particle representation using a non-perturbative variational technique. The theory is that of two massive scalar particles…
Variational Calculation of Relativistic Meson-Nucleon Scattering In Zeroth Order
A. W. Schreiber, R. Rosenfelder, C. Alexandrou
We extend the polaron variational treatment previously developed for the propagator to the case where one nucleon and external mesons are present. Using the particle representa…
Polaron Variational Methods In The Particle Representation Of Field Theory : II. Numerical Results For The Propagator
R. Rosenfelder, A. W. Schreiber
For the scalar Wick-Cutkosky model in the particle representation we perform a similar variational calculation for the 2-point function as was done by Feynman for the polaron probl…
Polaron Variational Methods In The Particle Representation Of Field Theory : I. General Formalism
R. Rosenfelder, A. W. Schreiber
We apply nonperturbative variational techniques to a relativistic scalar field theory in which heavy bosons (``nucleons'') interact with light scalar mesons via a Yukawa coupling.…
Nuclear Polarization Corrections for the S--Levels of Electronic and Muonic Deuterium
Yang Lu, R. Rosenfelder
We calculate the second-order corrections to the atomic energy level shifts in ordinary and muonic deuterium due to virtual excitations of the deuteron which are important for ongo…