'...Alfvén did a study of the most used textbooks on astrophysics and how they treated important concepts such as double layers, critical velocity, pinch effect and circuits. He found that <font color="#bd934f">"students using these textbooks remain essentially ignorant of even the existence of these concepts...</font>'<blockquote>'There is an alternative hypothesis about what we will find at the outer limit of the Sun's domain. It has had plenty of time to percolate its way into the consciousness of astrophysicists, if they cared to look up from their mathematical computer models.
In a paper, supported in part by NASA, Alfvén writes: <font color="#bd934f">"Since the time of Langmuir, we know that a double layer is a plasma formation by which a plasma–in the physical meaning of the word–protects itself from the environment. It is analogous to a cell wall by which a plasma (in the biological meaning of the word) protects itself from the environment.
"If a plasma is inhomogeneous so that the chemical composition, density, and/or electron temperature differs in different parts of the plasma, the plasma may set up double layers which split the plasma into two or more regions, each of which becomes more homogeneous."</font> [IEEE Transactions on Plasma Science, Vol. PS-14, No. 6, Dec 1986.]
In the above paper, Alfvén did a study of the most used textbooks on astrophysics and how they treated important concepts such as double layers, critical velocity, pinch effect and circuits. He found that <font color="#bd934f">"students using these textbooks remain essentially ignorant of even the existence of these concepts, despite the fact that some of them have been known for half a century (e.g., double layers, Langmuir, 1929; pinch effect, Bennet, 1934). [Make that three quarters of a century now.] The conclusion is that astrophysics is too important to be left in the hands of astrophysicists who have gotten their main knowledge from these textbooks. Earthbound and space telescope data must be treated by scientists who are familiar with laboratory and magnetospheric physics and circuit theory, and of course with modern plasma theory."</font>
The solar plasma and that of interstellar space are two different plasmas, which must therefore have a "double layer" or Langmuir plasma sheath between them...'
- Wal Thornhill,
Voyager 1 at the Edge – of what? 13 November 2005</font></blockquote>