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A virtual walk in the solar wind

A team at Warwick University is using virtual reality (VR) to study the chaotic paths of charged particles in the plasma that flows out from the Sun and gets trapped in the Earth’s magnetic field

	Charged particles trapped in the Earth’s magnetic field move on a Moebius strip just before their paths become chaotic

We have been using VR to understand the behaviour of charged particles (protons and electrons) in the complex magnetic field geometry of the Earth’s magnetosphere. The chaotic motion of these charged particles, and the corresponding sensitivity to small changes in initial conditions (the ‘butterfly effect’) may mean that they play a key role in the unpredictability of ‘space weather’ – the magnetic disturbances and the dynamic behaviour of the Aurora Borealis.

Of fundamental importance is the ‘route to chaos’ – that is, how the paths of charged particles become chaotic. The pictures opposite show two particle orbits in real space in the Earth’s geomagnetic tail, where the magnetic field differs by only 0.01 per cent. Just before becoming chaotic, the particles are found to move on a Moebius strip (a ontinuous band with a twist in it) in three-dimensional space. This then bifurcates (splits down the middle). Only by looking in true three-dimensional space in VR were we able to be sure that the orbits have the Moebius-strip topology. This then tells us what kind of mathematical description is needed to understand the problem.

Virtual reality (VR) is currently used to walk around buildings and to reproduce three-dimensional images of ‘real’ objects. We would like to take this further by fully immersing the user in the multidimensional abstract mathematical spaces that we use to formulate such ideas. In this way it may be possible to advance mathematics-based concepts more quickly.

A new facility for VR research which is being set up at Warwick will enable us to do this. It has been funded via the Joint Research Equipment Initiative, and the bid was one of only three supported in the PPARC area in an extremely competitive funding round. Our Space and Astrophysics group is leading the project but the facility will be used by a wide range of Warwick scientists to examine everything from abstract mathematics to engineering research.

Sandra Chapman University of Warwick
E-mail: S.C.Chapman@warwick.ac.uk