2025/07/01 by P. J. Käpylä, Käpylä, Petri J. · 1 voice
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Astro and Planetary Science #Geomagnetism and Paleomagnetism Studies #Solar and Space Plasma Dynamics
paper · pdf · doi:10.1007/s41116-025-00042-3
openalex publication_date 2025/09/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/13
Abstract Mean-field dynamo theory, describing the evolution of large-scale magnetic fields, has been the mainstay of theoretical interpretation of magnetism in astrophysical objects such as the Sun for several decades. More recently, three-dimensional magnetohydrodynamic simulations have reached a level of fidelity where they capture dynamo action self-consistently on local and global scales without resorting to parametrization of unresolved scales. Recent global simulations also capture many of the observed characteristics of solar and stellar large-scale magnetic fields and cycles. Successful explanation of the results of such simulations with corresponding mean-field models is a crucial validation step for mean-field dynamo theory. Here the connections between mean-field theory and current dynamo simulations are reviewed. These connections range from the numerical computation of turbulent transport coefficients to mean-field models of simulations, and their relevance to the solar dynamo. Finally, the most notable successes and current challenges in mean-field theoretical interpretations of simulations are summarized.