Dr Robert J Ewart has been awarded the European Physical Society Plasma Physics Division’s PhD Research Award. The Plasma Physics Division of the EPS recognises up to four scientists for truly outstanding research achievements associated with their DPhil study in the field of plasma physics.
Dr Ewart summarises his thesis, ‘Universal equilibria, phase-space structure of collisionless plasma systems, and turbulence in non-Maxwellian plasmas’: ‘The second law of thermodynamics tells us that things (milk in coffee, air in the room, the state of society, etc) become more disordered as time progresses: entropy increases. This might seem like terrible philosophical news but it is fantastic news scientifically. The reason for this is that disorder is more predictable that order so when we know a system is maximally disordered, we can deploy a whole toolkit of techniques to understand it. In a collisionless plasma – the focus of my thesis – things are not so simple. While the system still becomes incredibly disordered, it does so while preserving a very large number of invariants. In a sense, collisionless plasmas have a kind of “memory” of being ordered which stops them from becoming completely disordered. I showed that you can still use the tools from the toolkit for understanding disordered systems, but you have to take more care about the plasma's memory. Interestingly, when the system becomes strongly turbulent, we showed that the plasma effectively gets amnesia, and begins to behave in an entirely new, but very universal way.’
Dr Ewart studied for his DPhil at the Department of Physics at Oxford under the supervision of Professor Alex Schekochihin and is now a postdoctoral fellow at Princeton University, USA.
Dr Ewart is the seventh winner from the University of Oxford in recent years; he joins fellow alumni Dr Toby Adkins (2024), Dr David Hosking (2023), Dr Plamen Ivanov (2022), Dr Archie Bott (2020), Dr Justin Ball (2017) and Dr Edmund Highcock (2014).