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Wahlquist, H.

Publications and source records attributed to Wahlquist, H..

Constraint-free Theories of Gravitation

Lovelock actions (more precisely, extended Gauss-Bonnet forms) when varied as Cartan forms on subspaces of higher dimensional flat Riemannian manifolds, generate well set, causal exterior differential systems.

gravitation↗

Maximally slicing a black hole.

Analytic and computer-derived solutions are presented of the problem of slicing the Schwarzschild geometry into asymptotically flat, asymptotically static, maximal spacelike hypersurfaces. The sequence of hypersurfaces advances forward in time in both halves (u greater than or equal to 0, u less than or equal to 0) of the Kruskal diagram, tending asymptotically to the hypersurface r = 3/2 M and avoiding the singularity at r = 0. Maximality is therefore a potentially useful condition to impose in obtaining computer solutions of Einstein's equations.

Estabrook, F.↗

Shaped superconductor cylinder retains intense magnetic field

The curve of the inner walls of a superconducting cylinder is plotted from the flux lines of the magnetic field to be contained. This shaping reduces maximum flux densities and permits a stronger and more uniform magnetic field.

Hildebrandt, A. F.↗