D versus D Reconnection  Id just like to make a comment This article does a fine job describing reconnection in D The D generalization is not trivial though In D sweetparker or petcheck reconnection effectively becomes D nullpoint reconnection without getting into quaiseparatrix 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 flux system whereas the solar corona requires only a flux system  Okay I didnt realize how technical this article was going to be until I started writing it  Ill 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  Im currently conducting an experiment to study magnetic reconnection  if you have questions post them here or on my talk page  but be warned Ill be at a conference for the next week so my response may be slow   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 linetying 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 HP Killeen J and Rosenbluth M N  Phys of Fluids   Several researches have shown linetying the system simply slows the linear tearing mode growth rate see Velli M and Hood A W  Sol Phys   Velli M Einaudi G and Hood A W  ApJ    Preceding unsigned comment added by      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 cannot    The discussion still needs considerable work some work on the Xpoint figure it would be nice to have the seapratrices and separator marked an perhaps a D figure to visualize domain topology  but Im out of borrowed time for today    Happy new year      While it is true that topological separatricies exist independent of the plasma reconnection cannot occur in vacuum Reconnection absolutely requires a plasma because its the plasma that supports the dissipative current sheets that form along these separatricies  Dissent about Magnetic Reconnection Should notable peerreviewed papers dissenting with the theory of magnetic reconnection be included in the article  If so Nobel prize winning plasma physicist Hannes Alfvn the socalled Father of MHD has dissented in several articles Double Layers and Circuits in Astrophysics On frozenin field lines and fieldline reconnection calling magnetic merging reconnection a pseudoscience 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 Alfvn The conecepts frozenin magnetic field lines and fieldline 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