RESUMO
Two experimental bifurcation diagrams were obtained with two different control parameters. One parameter was the faucet opening and the other one, keeping fixed the faucet opening, was an electrical voltage (V) applied to a metallic cylinder that surrounds the pendant water column. In this way, the drops are formed in an electrical field gradient that polarizes the water column altering the effective surface tension that is consistent with the observed decreasing of the drop mass as the potential is increased, while the water flow rate remains constant. We observed that the two bifurcations are similar for S â² 65 and V â² 2.05 kV ; otherwise, the bifurcation evolutions are quite different.
RESUMO
It is shown that the deviations of the experimental statistics of six chaotic acoustic resonators from Wigner-Dyson random matrix theory predictions are explained by a recent model of random missing levels. In these resonatorsa made of aluminum plates a the larger deviations occur in the spectral rigidity (SRs) while the nearest-neighbor distributions (NNDs) are still close to the Wigner surmise. Good fits to the experimental NNDs and SRs are obtained by adjusting only one parameter, which is the fraction of remaining levels of the complete spectra. For two Sinai stadiums, one Sinai stadium without planar symmetry, two triangles, and a sixth of the three-leaf clover shapes, was found that 7%, 4%, 7%, and 2%, respectively, of eigenfrequencies were not detected.
RESUMO
We applied a recently proposed rescaling of curvatures of eigenvalues of parameter-dependent random matrices to experimental data from acoustic systems and to a theoretical result. It is found that the data from four different experiments, ranging from isotropic plates to anisotropic three-dimensional objects, and the theoretical result always agree with the universal curvature distribution, if only the curvatures are rescaled such that the average of their absolute values is unity.