We introduce models for the runaway coevolution of female mating preferences and male display traits. The models generalize earlier results by allowing for direct natural selection on the preference, arbitrary forms of mate choice, and fairly general assumptions about the underlying genetics. Results show that a runaway is less likely when there is direct selection on the preference, but that i...

The observable properties of a Type Ia supernova are sensitive to how the nuclear runaway ignites in a Chandrasekhar mass white dwarf at a single point at its center, off-center, or at multiple points and times. We present a simple analytic model for the runaway based upon a combination of stellar mixing-length theory and recent advances in understanding RayleighBenard convection. The convectiv...

[1] Analytical and numerical models of the radio frequency emissions produced by relativistic runaway electron avalanches initiated by cosmic ray extensive air showers are presented. It is found that single-point measurements of the distant electromagnetic fields allow the remote determination of the electrostatic field in the runaway electron avalanche region. For instance, it is possible to u...

Radiation from relativistic runaway electrons is considered as a source for plasma frequency radiation in tokamaks. Two specific emission mechanisms, Cerenkov emission, and radiation produced by nonlinear coupling of plasma and acoustic waves, are studied. In many cases the Cerenkov emission provides a reasonable spectral fit. It can also be used to measure the runaway current, and to est'imate...

We further investigate the runaway instability of relativistic tori around black holes assuming a power law distribution of the specific angular momentum. We neglect the self-gravity of the torus; thus the gravitational field of the system is determined by the central rotating black hole alone (the Kerr geometry). We find that for any positive (i.e. consistent with the local Rayleigh stability ...