We build an unbounded sequence of nonradial solutions for ∇(|x|−2a∇u)+ |x|− 2N N−2 au N+2 N−2 = 0, u > 0 in RN \{0} , where N ≥ 5 and a < 0. This answers an question of L. Veron.

The classiication of adiabatic modes of nonradial stellar oscillation was established by Cowling (1941). In addition to acoustic and gravity modes he identiied an intermediate mode, which he labelled the f mode, and which in simple stellar models has no radial node. The motion of a dipolar f mode (of spherical-harmonic degree l = 1) shifts the centre of mass, and must have zero frequency. On th...

The irrotational vortex geometry carachter of torsion loops is displayed by showing that torsion loops and nonradial flow acoustic metrics are conformally equivalent in (1 + 1) dimensions while radial flow acoustic spacetime are conformally related in (2 + 1) dimensional spacetime. The analysis of 2-dimensional space allows us to express the fluid density in terms of the parameters of torsion l...

Abstract We study a defocusing semilinear wave equation, with power nonlinearity $$|u|^{p-1}u$$ | u p - 1 , defined outside the unit ball of $$\mathbb {R}^{n}$$ R n</mml:m...

We introduce a model for pulsars in which nonradial oscillations of high spherical degree (l ) aligned to the magnetic axis of a spinning neutron star reproduce the morphological features of pulsar beams. In our model, rotation of the pulsar carries a pattern of pulsation nodes underneath our sight line, reproducing the longitudestationary structure seen in average pulse profiles, while the ass...