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 2nd March 2012, 04:20 PM #6614 Tim Thompson Muse     Join Date: Dec 2008 Posts: 969 Magnetic Reconnection Defined and Described II Originally Posted by Michael Mozina How are you distinguishing between ordinary magnetic flux and magnetic reconnection? Any change in the topology of the magnetic flux is magnetic reconnection by definition. See my earlier post Magnetic Reconnection Defined and Described (24 January 2012). The terms "magnetic flux" and "magnetic field" are related to each other as shown by the passages below ... Originally Posted by "Electromagnetic Fields and Waves", Lorrain & Corson, 1970, chapter 7 The next three chapters will deal with various aspects of magnetic fields. We shall start by studying in some detail the properties of two vector quantities, namely, the magnetic induction B and the vector potential A, which are used to describe magnetic fields. { ... } As in electrostatics, where we used lines of force to describe an electric field, we can describe a magnetic field by drawing lines of B that are everywhere tangent to the direction of B. Similarly, it is convenient to use the concept of flux, the flux of the magnetic induction B through a surface S being defined as the normal component of B integrated over S: $\phi = \int_s \bold B \cdot \bold {da}$ In Classical Electrodynamics by John David Jackson (John Wiley & Sons, Inc., 1999, 3rd edition), he uses the term "magnetic flux density" ... Originally Posted by Jackson, 1999 Already in the definition of the magnetic-flux density B (sometimes called the magnetic induction), we have a more complicated situation than for the electric field. It is not clear to me that you are using the term "magnetic flux" properly. These two quotes show the proper context of the terms, flux, flux density and induction, for magnetic fields. What is evident is that B, which we call the magnetic field, is related to flux by a simple surface integral. Change the topology of B and you will change the topology of its integrated flux. Likewise, if you want to change the topology of the integrated flux, you have to change the topology of B. The mathematical representation of this change in topology is by reconnection of the lines of force. This is a point I have made several times now, evidently to no avail. Of course the physical magnetic field is a continuum, nobody ever disputed that. However, also see my earlier post Magnetic Field Lines and Flux Tubes Defined, where we see Biskamp define a field line as a flux tube of infinitesimal diameter. But consider this ... Originally Posted by Michael Mozina Even still, "reconnection" requires PHYSICAL THINGS ... Magnetic fields exist and are physical things with topology. There is no law of physics which prevents the physical thing we call a magnetic field from altering its topology in a vacuum; there are laws of physics which require the topology of he magnetic field to change in a vacuum (Specifically Maxwell's equations in a vacuum). In what sense do you assert that a magnetic field is not a "physical thing"? Finally, it would surely clear things up a lot if Mozina chose to respond to this ... Originally Posted by Tim Thompson Originally Posted by Michael Mozina I do not reject the math's associated with "reconnection" theory either Tim. I reject the STUPID NAME you folks assigned to the PLASMA PROCESS. OK. Reference my post Magnetic Reconnection Defined and Described In the paper Magnetic Reconnection by Yamada, Kulsrud & Ji, we find this statement: "Understanding magnetic reconnection, a topological rearrangement of magnetic field lines, provides a key to these questions. In magnetized astrophysical and laboratory plasmas, magnetic reconnection rearranges the magnetic field-line configurations restructuring macroscopic quantities of plasmas such as flow and thermal energy." Do you agree with this? Specifically, do you agree that the magnetic field lines reconfigure to change the topology of the magnetic field? In the book Magnetic Reconnection: MHD Theory and Applications by Priest & Forbes we find this statement: "As we shall discuss in more detail later on, magnetic reconnection is essentially a topological restructuring of a magnetic field caused by a change in the connectivity of its field lines. This change allows the release of stored magnetic energy, which in many situations is the dominant source of free energy in a plasma." Do you agree with this? Specifically, do you agree that the change in the topology of the magnetic field is caused by changes in the connectivity of the magnetic field lines? In the paper Review of controlled laboratory experiments on physics of magnetic reconnection by Masaaki Yamada we find this statement: "Magnetic reconnection is the topological breaking and rearrangement of magnetic field lines in a plasma and is the most fundamental process in the interplay between plasma and magnetic field (Parker, 1979; Priest, 1984; Vasyliunas, 1975)." Do you agree with this? Specifically, do you agree that the magnetic field lines break and then rearrange into a different topology? The plasma processes associated with magnetic reconnection happen because first the topology of the magnetic field changes to that of a lower energy state and then the energy is transferred to the plasma which reacts accordingly. So why is "magnetic reconnection" a "stupid name", when it is in fact the root cause of the plasma process to begin with? And if in fact you accept the math, as you claim you do, and the math shows field lines reconnecting, then again, why is it a "stupid name"? __________________ The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it. -- Bertrand Russell