ABSTRACTS OF PAPERS TO APPEAR IN FUTURE ISSUES 213 Independent measures of the volume per defect can be derived from (i) the Edwards-Anderson correlation function, and (ii) the number of local minima in large systems. It is noted that in the limit M + co, (defect separation) s (core size) > (nearest-neighbor distance). Gravitational Contribution to the Casimir Energy in Kalura-Klein Theories. ALAN CHODOS AND ERIC MYERS. Department of Physics, Yale University, New Haven, Connecticut 065 11. The Casimir energy of the gravitational field in Kaluza-Klein theories is investigated. The mathematical techniques needed to compute the contribution of a single graviton loop to the quantum effective potential on a background manifold of (Minkowski space) @ (N-sphere) are developed. In these computations the cosmological constant plays a dynamical role, acting like a mass for the graviton. The numerical work for the case N = 1 is done explicitly, and a solution to the one-loop corrected equations of motion is found, although it is not stable. The possibility of an imaginary part to the effective potential for N > I is noted, and its existence is attributed to tachyonic terms in the mode sum. An Eflective Action for a Variable Electromagnetic Field. JOHAN HAUKNES. Institute of Physics. University of Oslo, Oslo, Norway. This work consists essentially of two parts. The first part is an analysis of the one-loop effective action using the zeta-function approach. This gives a simple expression for the effective action in terms of the background field propagator. The next-of-kin to the zeta-function, the heat kernel, is given in terms of B. Dewitt’s proper time expansion (also known as P. B. Gilkey’s theorem). It is calculated in the second part for fermions interacting with an external electromagnetic field to first nonvanishing order in the variations of the gauge field. Meson Lagrangians in a Superconductor Quark Model. M. K. VOLKOV. Joint Institute for Nuclear Research, Dubna, U.S.S.R. On the basis of an effective “superconductivity”-type four-quark interaction, phenomenological Lagrangians are obtained for interactions of scalar. pseudoscalar, vector, and axial vector meson nonets. The Lagrangians include mass terms breaking chiral and U(3) invariance and corresponding to the quark masses m, # md # m,. It is shown that upon introducing boson fields the masses of current quarks in the initial Lagrangian are replaced by the masses of constituent quarks in the phenomenological boson Lagrangians. Estimates of these masses are presented. Electromagnetic interactions are considered, and the vector dominance model is derived. The widths of various meson decays are calculated. Prinred in Belgium

An effective action for a variable electromagnetic field: Johan Hauknes. Institute of Physics, University of Oslo, Oslo, Norway

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Page 1: An effective action for a variable electromagnetic field: Johan Hauknes. Institute of Physics, University of Oslo, Oslo, Norway

ABSTRACTS OF PAPERS TO APPEAR IN FUTURE ISSUES 213

Independent measures of the volume per defect can be derived from (i) the Edwards-Anderson correlation function, and (ii) the number of local minima in large systems. It is noted that in the limit M + co, (defect separation) s (core size) > (nearest-neighbor distance).

Gravitational Contribution to the Casimir Energy in Kalura-Klein Theories. ALAN CHODOS AND ERIC MYERS. Department of Physics, Yale University, New Haven, Connecticut 065 11.

The Casimir energy of the gravitational field in Kaluza-Klein theories is investigated. The mathematical techniques needed to compute the contribution of a single graviton loop to the quantum effective potential on a background manifold of (Minkowski space) @ (N-sphere) are developed. In these computations the cosmological constant plays a dynamical role, acting like a mass for the graviton. The numerical work for the case N = 1 is done explicitly, and a solution to the one-loop corrected equations of motion is found, although it is not stable. The possibility of an imaginary part to the effective potential for N > I is noted, and its existence is attributed to tachyonic terms in the mode sum.

An Eflective Action for a Variable Electromagnetic Field. JOHAN HAUKNES. Institute of Physics. University of Oslo, Oslo, Norway.

This work consists essentially of two parts. The first part is an analysis of the one-loop effective action using the zeta-function approach. This gives a simple expression for the effective action in terms of the background field propagator. The next-of-kin to the zeta-function, the heat kernel, is given in terms of B. Dewitt’s proper time expansion (also known as P. B. Gilkey’s theorem). It is calculated in the second part for fermions interacting with an external electromagnetic field to first nonvanishing order in the variations of the gauge field.

Meson Lagrangians in a Superconductor Quark Model. M. K. VOLKOV. Joint Institute for Nuclear Research, Dubna, U.S.S.R.

On the basis of an effective “superconductivity”-type four-quark interaction, phenomenological Lagrangians are obtained for interactions of scalar. pseudoscalar, vector, and axial vector meson nonets. The Lagrangians include mass terms breaking chiral and U(3) invariance and corresponding to the quark masses m, # md # m,. It is shown that upon introducing boson fields the masses of current quarks in the initial Lagrangian are replaced by the masses of constituent quarks in the phenomenological boson Lagrangians. Estimates of these masses are presented. Electromagnetic interactions are considered, and the vector dominance model is derived. The widths of various meson decays are calculated.

Prinred in Belgium