Galactic magnetic fields: connecting theory, simulations, and observations

Galactic magnetic fields
Amit Seta
Start Date
End Date

You can find a recording of this meeting on our YouTube channel:


Magnetic fields are an important energy-carrying component of spiral galaxies. Their properties are usually explained by a dynamo theory, the mechanism by which kinetic energy is converted into magnetic energy in the turbulent, differentially rotating and stratified interstellar medium of a galaxy. 

Magnetic fields of galaxies are studied via multiple methods: observations, theoretical models, and simulations on a variety of scales. Turbulent dynamos are now also being studied using laboratory experiments. However, even after several decades of work on galactic magnetic fields, models are arguably still not very predictive. This is perhaps understandable given the great complexity and interwovenness of the relevant physical processes, the extraordinary diversity of galaxies which limits the usefulness of generic models, and the considerable challenge of comparing indirect observations of magnetic fields with idealized models.

Despite these hurdles, there is now ample opportunity for progress owing largely to bigger and better simulations and powerful new or forthcoming observational instruments. Not to mention steady advancement in analytic theory and data analysis techniques, as well as new ground-breaking dynamo experiments. To take full advantage of this opportunity, researchers in each subfield must (i) make use of work in other subfields and (ii) make their work usable by other subfields. 


In this RAS specialist meeting, we aim to initiate a dialogue between experts from various subfields that we hope will lead to more comparisons across them. To foster active discussion and collaboration we aim to discuss the following questions:

  • How are large- and small-scale dynamos related?
  • How do small-scale magnetic fluctuations affect larger-scale observations?
  • What are the magnetic scales in the ISM? To what extent does the scale separation in galactic magnetic fields exist?
  • Is mean field dynamo theory useful in the age of direct numerical simulations?
  • What do we expect to achieve with rich polarisation data from the SKA?
  • What are the expected observational signatures of galactic dynamos from simulations and theory?
  • Do magnetic fields affect galaxy formation and evolution?
  • How do cosmic rays interact with magnetic fields in the multiphase ISM and what are related observational probes?
  • What do experiments of laser-plasma turbulence tell us about dynamo theory, and galactic dynamo theory in particular?


Invited speakers

  • Rainer Beck (MPIfR, Germany)
  • Axel Brandenburg (Nordita, Sweden)
  • Marijke Haverkorn (Radboud University, Netherlands)
  • Sui Ann Mao (MPIfR, Germany)
  • Ruediger Pakmor (MPA, Germany)
  • Anvar Shukurov (Newcastle University, UK)
  • Kandaswamy Subramanian (IUCAA, India) 
  • Petros Tzeferacos (University of Rochester, USA)
  • Ellen Zweibel (University of Wisconsin, USA)

Abstract submission for pre-recorded talks is open until 15th September 2021 via


Amit Seta (Australian National University, Canberra)

Luke Chamandy (University of Rochester, USA)