I work in the general area of theoretical plasma physics. This field provides a rich array of problems in classical field theory, fluid dynamics, nonlinear dynamics and chaos, and nonequilibrium statistical mechanics.  I work mainly in problems related to laboratory plasmas, in particular to the toroidal magnetic confinement approach to the development of fusion power, but have also an interest in space and astrophysical plasmas.

My current research: In a recent paper by R.L. Dewar and Z.S. Qu, J. Plasma Phys. 88, 835880101 (2022), we proposed a variational augmented Lagrangian approach to regularization of the ideal MHD equations in such a way that relaxation of magnetic field line topology is allowed.  The basic hypothesis of this weak formulation of ideal MHD is that uniform convergence as L² tolerance parameters go to zero will fail in neighbourhoods of points where reconnection would occur in a weakly resistive plasma. Relaxation is difficult to simulate using resistive MHD with realistically small resistivity as this is a singular limit. Thus the hope is that weak ideal MHD forms a proxy for resistive MHD that will allow easier and more rapid simulation of reconnection phenomena, allowing magnetic islands and chaos to form as geometric symmetry is broken in the optimization of toroidal magnetic plasma containment devices (stellarators).

The short-term plan is to verify the above hypothesis numerically in a simple plasma geometry and compare it with an alternative Voigt regularization approach by P. Constantin and F. Pasqualotto, arXiv:2208.11109.  A longer-term goal is to build new and better 3-D MHD equilibrium, evolution and stability computer codes for use in the Simons Collaboration on stellarator optimization 'Hidden Symmetries and Fusion Energy,' and other physical applications.

CURRICULUM VITAE
Emeritus Professor Robert Leith DEWAR, FAA

Date and Place of Birth: March 1, 1944, Melbourne

Academic Qualifications:
BSc (1964), MSc (1967), University of Melbourne.
PhD (1970) Princeton University.

Honours:
Centenary Medal, 2003.
Elected Fellow of the Australian Academy of Science, 1992.
Elected Fellow of the American Physical Society, 1980.

Membership of Learned Societies (See Honours above for Fellowships):
Australian Institute of Physics.
Australian Mathematical Society.

Research Career:
I began my career with my much-cited 1970 paper on a general MHD theory of wave-mean flow interaction using Hamilton’s Action Principle, using a general formalism I have adapted in my recent first-author publications. This recent work is aimed at generalizing the Multiregion Relaxed MHD approach I and my collaborators developed in a series of Australian Reseearch Council grants leading to the SPEC 3-D MHD equilbrium code. I am currently a founding Principal Investigator for ANU in the international Simons Collaboration on “Hidden Symmetries and Fusion energy”. I have a long history of participation in code development and application, being intimately involved with the development of the PPPL/ANU linear MHD stability code series PEST1, PEST2 and PEST3. I have supervised 5 postdocs, 14 PhD, 3 Masters and 2 Honours students to completion. Being a retired Emeritus Professor I am free of university administrative and teaching load and have remained active in research.

Metrics:
Web of Science/Publons
https://www.webofscience.com/wos/author/record/917070
Google Scholar
https://scholar.google.com.au/citations?user=m-hrp8sAAAAJ&hl=en

Recent Appointments:
Emeritus Professor, The Australian National University 
– Research School of Physics & Engineering, March 2011 - June 2018;
– Mathematical Sciences Institute, July 2018 - present)
Senior Past Appointments:
Professor, Level E(1), The Australian National University, October 1992 - July 1996
Professor, Level E(2), Institute of Advanced Studies, Research School of Physics & Engineering (RSPE), ANU, July 1996 - February 2011 Head, Plasma Research Laboratory, RSPhysSE, January 1995 - February 1997 Interim Director, National Plasma Fusion Research Facility, Feb. 1996 - Feb. 1997
Head, Department of Theoretical Physics, RSPhysSE, August 1998 - July 2001
Convenor, ARC Complex Open Systems Research Network (COSNet) 2004 - 2009

• Weak (ideal almost everywhere) formulations of Magnetohydrodynamics (MHD) via regularization methods
• Multi-region relaxation model of self-organization in magnetized three-dimensional plasmas.
• Breakup of invariant (KAM) tori in Hamiltonian systems and its effect on transport -- a problem in classical chaos theory.
• Linear spectrum of waves and instabilities in stellarators -- a classical application of "quantum chaos" theory.