Introduction to Magnetohydrodynamics 2nd Edition

Book Preface

Some 15 years have passed since the first edition of this book was published, and it seems natural to revisit the subject after so long a break, reacquainting oneself with an old friend, so to speak.

If an excuse were required to revisit MHD after such a prolonged absence, then the recent advances in geophysical and astrophysical applications provide ample motivation. Astrophysical MHD, for example, has made great progress, partially as a result of the extraordinary observational data gathered from spacecraft-based instruments. On the other hand the relentless rise in computing power has, for the first time, made it possible to compute certain (but certainly not all) aspects of planetary dynamos, heralding a new wave of dynamo theories. As a result, the geophysical and astrophysical applications of MHD are now more thoughtprovoking and inviting than ever before.

So how should one update a book in the light of these developments? Clearly there is a need to place more emphasis on the geophysical and astrophysical applications in a second edition, which in any event provides the perfect excuse for offering a more balanced presentation of MHD. So Chapter 14, on planetary dynamos, and Chapter 15, on astrophysical applications, are largely new. Another omission in the first edition was an absence of fusion plasma MHD, and it is hoped that this has been remedied by the addition of Chapter 16. Between them, Chapters 14 through 16 provide an introduction to many of the applications of MHD in physics, and the author thanks Felix Parra Diaz and Gordon Ogilvie for providing helpful comments on draft versions of Chapters 15 and 16. Perhaps the final major addition is an extended treatment of turbulence (in Chapter 8) andMHD turbulence (in Chapter 9), which reflect recent progress in theories of MHD turbulence. Despite this shift in emphasis, the engineering applications, which were a particular feature of the first edition, have been largely retained as they are sadly underrepresented elsewhere in textbooks on MHD.

Despite these changes, the ambition of the text remains largely the same: to provide a self-contained introduction to MHD for graduate and advanced undergraduate students, with background material on electromagnetism and fluid mechanics developed from first principles, and with the fundamental theory illustrated through a broad range of applications.