Modelling pulsar timing noise

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Context: Pulsars - rotating neutron stars - are observed to gradually spin down, with the apparent loss in kinetic energy balancing a flux of electromagnetic and gravitational wave energy from the star. This spin down is smooth, but not perfectly so, with departures from a simple timing model being known as pulsar timing noise. The origin of this noise is not understood. The aim of this project is to develop mathematical models that describe this phenomenon.Key objective and aims: the key objective is to build a model of a neutron star that incorporates the wide range of physical inputs that are likely to be important in this problem. The outputs of such a model would be compared against real timing noise and the model parameters adjusted so as to reproduce as accurately as possible the observed spin behaviour. In this way, the behaviour of fluids and solids in extremes of gravity, density and magnetic field would be probed, in a way that would simply not be possible in a terrestrial laboratory.Novel methodology: the novel methodology lies in developing perturbation techniques to describe small departures from uniform rigid body spin-down, that include gravitational, elastic and magnetic forces. Then new numerical techniques to evolve the system on a computer would be developed, and used to explore the consequences of the model.EPSRC research areas: The highly complex physics of neutron stars means that this project is relevant to multiple EPSRC research areas. Mathematical physics and Complexity science are the most obviously relevant areas, but there is also overlap with Cold atoms and molecules, Condensed matter: magnetism and magnetic materials, and Quantum fluids and solids.