Treatment I. MAHIR S. HUSSEIN. Pelletron LaboUniversity of Sao Paula, Sao Paulo, Brasil.
A Four-Body
In an external magnetic field analytical properties are studied of the photon polarization tensor calculated as the electron-positron loop in the Furry picture. The polarization tensor is reexpressed as a sum over singular contributions coming from e+e--pair photocreation in semidiscrete Landau states. The solutions of the photon dispersion equation (i.e., the one for the poles of the photon propagator) are described. The shape of the photon dispersion curve obtained is responsible for the effect of photon deflection by a strong magnetic field. No physically reliable solutions, apart from spurions, are found for the longitudinal photon mode. An infinite number of solutions with complex space-momentum are found, with no apparent ghosts among them. An attempt is made to interprete the former in terms of possible bound and quasibound states of electron and positron pairs.
Irregular
Dielectric
or Permeable
bridge Research Laboratories,
Bodies in an External Field. LEONARD EYGES. Air Force CamLC Hanscom AFB Bedford, Massachusetts 01730.
An integral equation is derived for the electrostatic potential # that arises when a uniform dielectric body of arbitrary shape is placed in an applied electrostatic field. By expansion of # in a certain basic set, the integral equation becomes a set of linear equations for the expansion coefficients, and it is often practical to solve the set by truncation. As a test, the equations are applied to the problem of a spheroid in a uniform field, and they easily yield the standard results that are usually derived by introducing spheroidal harmonics. Either the integral equation or the equivalent linear equations can be solved in an iterative approximation (the analog of the Born approximation) when the dielectric constant of the body is not too far from unity. For bodies that differ from spherical or cylindrical ones by a small parameter h, perturbation formulae are derived that solve the equations in powers of A. The problem of a homogeneous permeable body of arbitrary shape in an external magnetostatic field is reducible to the dielectric problem, but in addition an alternate integral equation for the magnetic problem is discussed.
Schwinger’s source theory is applied to the problem of gravitation and its quantization. It is shown that within the framework of a flat-space the source theory implementation leads to a violation of probability. To avoid the difficulty one must introduce a curved space-time hence the source concept may be said to necessitate the transition to a curved-space theory of gravitation. It is further shown that the curved-space theory of gravitation implied by the source theory is not equivalent to the conventional Einstein theory. The source concept leads to a different theory where the gravitational field has a stress-energy tensor tpy which contributes to geometric curvatures.
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