SoylentNews is people
SoylentNews
Magnetic reconnection could be the Universe's favorite way to make things explode. It operates anywhere magnetic fields pervade space—which is to say almost everywhere. In the cores of galaxies, magnetic reconnection sparks explosions visible billions of light-years away. On the sun, it causes solar flares as powerful as a million atomic bombs. At Earth, it powers magnetic storms and auroras. It's ubiquitous. The problem is, researchers can't explain it.
The basics are clear enough. Magnetic lines of force cross, cancel, reconnect and—Bang! Magnetic energy is unleashed, with charged-particles flying off near the speed of light. But how? How does the simple act of criss-crossing magnetic field lines trigger such a ferocious explosion?
http://science.nasa.gov/science-news/science-at-nasa/2015/10mar_mms/
[Also Covered By]: http://phys.org/news/2015-03-nasa-magnetic-explosions.html
(Score: 3, Interesting) by fritsd on Friday March 13 2015, @06:13PM
Maybe it has something to with phase transitions that are not allowed to "break the rules" of symmetry?
I'm just talking out of my arse here, but the reference to "magnetic lines of force cross (...)" reminded me both of the film Ghostbusters, and also of a phenomenon from solid-state chemistry, which I forgot almost all about.. (just like Ghostbusters in fact)
Best to show with a picture since I can't draw and anyways I couldn't show it on soylentnews..
I found a picture on Google: http://ej.iop.org/images/0295-5075/54/3/354/Full/img19.gif [iop.org]
If you look at the graph on the left, follow the third and fourth line from the top with your eyes for increasing values of q:
there's a transition at q approx 0.35 and freq approx. 3.5 reciproke cm where you would expect the third and fourth line to cross (never mind what their *meaning* is, but you'd expect to see a continuation of two smooth lines).
But they don't.
They're not allowed to; that would break symmetry rules.
So at the transition point itself, there's a very weird "evasion" phase after which line #3 (counted from the top) will follow the curve that you'd expect the increasing line #4 to follow, and line #4 will follow the curve that you'd expect the decreasing line #3 to follow.
And for a bit higher q, the same for lines #2 and #3, and a bit higher lines #1 and #2.
I vaguely remember the reasons to be quantum mechanical in nature (probably Pauli exclusion principle?), however the graph is drawn from macroscopic, measurable phenomena.
And in this example; don't you have one of the Maxwell equations that says magnetism within a thingy (any thingy) is 0? Wasn't there a surface integral or something?
Let's see how good soylentnews' UTF-8 support is..
Gauss' law for magnetism:
∮ B ∙ dA = 0
So the system has states where the magnetism vanishes. So what happens if you *approach* such a state?
Forgive me if this all didn't make much sense..
(Score: 3, Interesting) by Alfred on Friday March 13 2015, @06:39PM
I didn't like EM Theory but I remember that when you have something pointy that the field behavior is different. Of course every geometry is different but the field lines would concentrate at the pointy part or something.
In a more universal approach, change is the only thing that remains the same but nothing likes to change too fast. Change to fast and things break, which can look really cool or be very painful.