B. Lars G. Jonsson

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We study solutions close to solitary waves of the pseudo-relativistic Hartree equation describing boson stars under the influence of an external gravitational field. In particular, we analyze the long-time effective dynamics of such solutions. In essence, we establish a (long-time) stability result for solutions describing boson stars that move under the(More)
We study the motion of solitary-wave solutions of a family of focusing generalized nonlinear Schrödinger equations with a confining, slowly varying external potential, V (x). A Lyapunov-Schmidt decomposition of the solution combined with energy estimates allows us to control the motion of the solitary wave over a long, but finite, time interval. We show(More)
1 This series is divergent, therefore we may be able to do something with it. Oliver Heaviside Nature laughs at the difficulties of integration. Abstract In the present paper an iterative time-reversal algorithm, that retrofocuses an acoustic wave field to its controllable part is established. For a fixed temporal support, i.e., transducer excitation time,(More)
We study the nonlinear equation i∂ t ψ = −∆ + m 2 − m ψ − (|x| −1 * |ψ| 2)ψ on R 3 , which is known to describe the dynamics of pseudo-relativistic boson stars in the mean-field limit. For positive mass parameters, m > 0, we prove existence of travelling solitary waves, ψ(t, x) = e itµ ϕ v (x − vt), with speed |v| < 1, where c = 1 corresponds to the speed(More)
While they account for one-fifth of new cancer cases, rare cancers are difficult to study. A higher than average degree of uncertainty should be accommodated for clinical as well as for population-based decision making. Rules of rational decision making in conditions of uncertainty should be rigorously followed and would need widely informative clinical(More)
Captive breeding and release programs, widely used to supplement populations of declining species, minimize juvenile mortality to achieve rapid population growth. However, raising animals in benign environments may promote traits that are adaptive in captivity but maladaptive in nature. In chinook salmon, hatchery rearing relaxes natural selection favoring(More)
Fundamental limitations restrict the bandwidth of electrically small antennas. A method to obtain such limitations is based on stored electric and magnetic energies. Vandenbosch recently proposed a set of integral expression for the stored energies. These expressions provide a method to determine optimal currents and physical bounds on antennas for maximal(More)
An upper bound on the effective area and bandwidth product for linearly polarized array antennas is derived. The bound is based on the forward scattering sum rule that relates the antenna properties with the polarizability of the antenna structure. The results are illustrated for a dipole array and a capacitively loaded dipole array with numerical(More)
The equations for the electromagnetic field in an anisotropic media are written in a form containing only the transverse field components relative to a half plane boundary. The operator corresponding to this formulation is the electromagnetic system's matrix. A constructive proof of the existence of directional wave-field decomposition with respect to the(More)