2D versus 3D Reconnection I d just like to make a comment This article does a fine job describing reconnection in 2D The 3D generalization is not trivial though In 3D sweet parker or petcheck reconnection effectively becomes 3D null point reconnection without getting into quai separatrix layers versus true separatricies In addition the application to the Magnetosphere is very different than the application to the solar corona in that magnetospheric reconnection topologically requires a 4 flux system whereas the solar corona requires only a 2 flux system Okay I didn t realize how technical this article was going to be until I started writing it I ll make an effort to fill in some of the empty links provide a diagram or three and place links to this article on the relevant pages I m currently conducting an experiment to study magnetic reconnection if you have questions post them here or on my talk page but be warned I ll be at a conference for the next week so my response may be slow 00 51 14 Nov 2004 UTC I removed an anonymous edit that claimed magnetic reconnection occurs when the magnetic pressure exceeds the plasma pressure ie when the plasma parameter is less than unity This is not the case Magnetic reconnection or the lack thereof is related to the line tying effect of high electrical conductivity not to the magnetic pressure Zowie While you are correct that reconnection occurs in both high and low beta plasmas the process is local and does not depend on whether the system is line tied or not Formally magnetic reconnection is the tearing mode of resistive MHD instability theory see Furth H P Killeen J and Rosenbluth M N 1963 Phys of Fluids 6 459 Several researches have shown line tying the system simply slows the linear tearing mode growth rate see Velli M and Hood A W 1989 Sol Phys 119 107 Velli M Einaudi G and Hood A W 1990 ApJ 350 419 Preceding unsigned comment added by 137 79 89 69 Topology rather than current sheets I took the liberty of reducing the discussion of current sheets which are not directly related to reconnection they are in some sense a symptom of lack of magnetic reconnection and instead introduced separatrix surfaces and separators the topological terms describing the domain boundaries Note that separatrices and magnetic reconnection can exist in a vacuum while current sheets can not The discussion still needs considerable work some work on the X point figure it would be nice to have the seapratrices and separator marked an perhaps a 3 D figure to visualize domain topology but I m out of borrowed time for today Happy new year While it is true that topological separatricies exist independent of the plasma reconnection can not occur in vacuum Reconnection absolutely requires a plasma because it s the plasma that supports the dissipative current sheets that form along these separatricies Dissent about Magnetic Reconnection Should notable peer reviewed papers dissenting with the theory of magnetic reconnection be included in the article If so Nobel prize winning plasma physicist Hannes Alfv n the so called Father of MHD has dissented in several articles Double Layers and Circuits in Astrophysics On frozen in field lines and field line reconnection calling magnetic merging reconnection a pseudo science More recently electrical engineer Don Scott has also published a dissenting paper Real Properties of Electromagnetic Fields and Plasma in the Cosmos Of course not That would be scientific heresy This is about proping up failed theories and supporting misguided research To quote Alfv n The conecepts frozen in magnetic field lines and field line reconnection play a certain role in discussions of the theory of the magnetosphere The use of these concepts has been criticized and we shall here demonstrate that both concepts are unnecessary and often misleading Oh btw you forgot another paper show