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We generalize simplicial minisuperspace models associated with restricting the topology of the universe to be that of a cone over a closed connected combinatorial 3-manifold by considering the presence of a massive scalar field. By restricting all the interior edge lengths and all the boundary edge lengths to be equivalent and the scalar field to be homogeneous on the 3-space, we obtain a family of two-dimensional models that includes some of the most relevant triangulations of the spatial universe. After studying the analytic properties of the action in the space of complex edge lengths we determine its classical extrema. We then obtain steepest-descent contours of constant imaginary action passing through Lorentzian classical geometries yielding a convergent wavefunction of the universe, dominated by the contributions coming from these extrema. By considering these contours we justify semiclassical approximations based on those classical solutions, clearly predicting classical spacetime in the late universe. These wavefunctions are then evaluated numerically. For all of the models examined we find wavefunctions predicting Lorentzian oscillatory behaviour in the late universe.

Using a laminated ceramic piezoelectric actuator for a very slow (4.5 mm/s) precisely controlled make/break operation, the contact voltage V c , the contact current I c , and the amounts of residue of the melt and discharged surface and discharge for breaking hinge relays with Ag-contacting electrodes were measured. To control mechanical conditions, we used a movable electrode with a finely shaped convex surface (radius of curvature: 0.5 mm) and a flat fixed electrode. Every make/break operation causes surface irregularity. Therefore, the operation was performed only once. In order to measure the area of the contacted surface after metal melting and arc ignition, V c and I c was adjusted to be 25 V and 1.2 A, respectively. Even when V c and I c were larger than the minimum arc voltage and minimum arc current, respectively, electric discharge was spontaneously suppressed below 130 ms. The residues of discharge were multiple scars with radii in the range of 100 mm, which had a black and/ or white rectangular convex or concave shape. #

From a study of the EPR of Mn" in K,SO, as a function of temperature, Chowdari and Venkateswarlu reported a possible phase transition at 143 K. To test whether a phase transisition really occurs, the spectra due to Mn2+ in K,SO, have been re-examined in our laboratory as a function of temperature. It was found that the Mn2+ ions occupy two sites, which are quite different from those proposed by Chowdari and Venkateswarlu, and these have been identified and analysed in detail at 4.2, 77 and 300 K at both Xand Q-band frequencies. The variation of the spin hamiltonian parameters B: and B i for the site with the stronger spectrum has been determined throughout the temperature range 4.2-300 K. No evidence for any phase transition was found.