24 research outputs found
Scaling Behavior in the Stable Marriage Problem
We study the optimization of the stable marriage problem. All individuals
attempt to optimize their own satisfaction, subject to mutually conflicting
constraints. We find that the stable solutions are generally not the globally
best solution, but reasonably close to it. All the stable solutions form a
special sub-set of the meta-stable states, obeying interesting scaling laws.
Both numerical and analytical tools are used to derive our results.Comment: 6 pages, revtex, 3 figures. To appear in J. de Physique I, vol 7, No
12 (December
Wormhole cosmic strings
We construct regular multi-wormhole solutions to a gravitating model
in three space-time dimensions, and extend these solutions to cylindrical
traversable wormholes in four and five dimensions. We then discuss the
possibility of identifying wormhole mouths in pairs to give rise to Wheeler
wormholes. Such an identification is consistent with the original field
equations only in the absence of the -model source, but with possible
naked cosmic string sources. The resulting Wheeler wormhole space-times are
flat outside the sources and may be asymptotically Minkowskian.Comment: 17 pages, LaTeX, 4 figures (hard copy available on request
On paraquaternionic submersions between paraquaternionic K\"ahler manifolds
In this paper we deal with some properties of a class of semi-Riemannian
submersions between manifolds endowed with paraquaternionic structures, proving
a result of non-existence of paraquaternionic submersions between
paraquaternionic K\"ahler non locally hyper paraK\"ahler manifolds. Then we
examine, as an example, the canonical projection of the tangent bundle, endowed
with the Sasaki metric, of an almost paraquaternionic Hermitian manifold.Comment: 13 pages, no figure
Measurement of the total and partial pp cross section between 1901 and 1950 MeV
The presence of a structure in the pp total cross section at 1930-1940 MeV, with a narrow width of 9 MeV is confirmed. The interpretation of the effect as a single, non interfering, resonance is made difficult by the comparison of the elastic scattering with the charge exchange cross sections. (8 refs)