On Friday, 21 April 2017 11:55:11 UTC+1, Weatherlawyer wrote:
I don't suppose there is anyone on here that can help me understand Feynma's diagrammes as applied tot hte solar system is there?
http://weatherlawyer.altervista.org/the-atlantic-too/

Thanks for posting that link. I really enjoyed it. Or as Feynman replies to Fred Hoyle, who has just remarked that "it's a depressing and sobering thought", "Well, it's good fun."

Feynman diagrams don't apply to the solar system. AIUI, they are theoretical bubble chamber diagrams describing the interaction of sub atomic particles.

"Alastair" wrote in message
...

AIUI, they are theoretical bubble chamber diagrams describing the
interaction of sub atomic particles.

Bubble chambers don't really come into it (unless you arrange your particle
collision to happen inside one I suppose). As you say, they are just
notional or theoretical sketches of what might happen when 2 or more
specified atomic/subatomic particles collide and interact to produce
offspring.

OT, but not totally, I did think this was quite an interesting YouTube talk:

https://www.youtube.com/watch?v=L0KuAx1COEk

(NB The first few minutes are just an introduction - you can skip that).
These REBCO ribbons or tapes seem like a real step forwards in
superconductors.

On Monday, 1 May 2017 06:14:38 UTC+1, Weatherlawyer wrote:
On Friday, 21 April 2017 17:55:59 UTC+1, JohnD wrote:
"Alastair" wrote in message
...

AIUI, they are theoretical bubble chamber diagrams describing the
interaction of sub atomic particles.

Bubble chambers don't really come into it (unless you arrange your particle
collision to happen inside one I suppose). As you say, they are just
notional or theoretical sketches of what might happen when 2 or more
specified atomic/subatomic particles collide and interact to produce
offspring.

OT, but not totally, I did think this was quite an interesting YouTube talk:

https://www.youtube.com/watch?v=L0KuAx1COEk

This might be interesting had we not already seen how this happens with volcanicity:

Magnetic Reconnection Onset via Disruption of a Forming Current ...
https://arxiv.org › astro-ph
by DA Uzdensky - ‎2014 - ‎Cited by 14 - ‎Related articles
16 Nov 2014 - ... Reconnection Onset via Disruption of a Forming Current Sheet by the Tearing Instability. Authors: Dmitri A. Uzdensky, Nuno F. Loureiro.
Missing: universe ‎magnitises ‎itself...
Some results may have been removed under data protection law in Europe. Learn mo


(Submitted on 16 Nov 2014 (v1), last revised 19 Feb 2016 (this version, v2))

The recent realization that Sweet-Parker current sheets are violently unstable to the secondary tearing (plasmoid) instability implies that such current sheets cannot occur in real systems. This suggests that, in order to understand the onset of magnetic reconnection, one needs to consider the growth of the tearing instability in a current layer as it is being formed.

Such an analysis is performed here in the context of nonlinear resistive MHD for a generic time-dependent equilibrium representing a gradually forming current sheet. It is shown that two onset regimes, single-island and multi-island, are possible, depending on the rate of current sheet formation.

A simple model is used to compute the criterion for transition between these two regimes, as well as the reconnection onset time and the current sheet parameters at that moment. For typical solar corona parameters this model yields results consistent with observations.

Comments: 5 pages, no figures; accepted for publication in Physical Review Letters

Conclusions. In this study we have developed a general conceptual framework connecting two important and
related phenomena that have hitherto been considered
separately: large-scale ideal MHD processes leading to
thin current sheet formation and magnetic energy accumulation and the onset of fast energy release through
reconnection.

In our picture, the immediate outcome of this sequence of events is the disruption (and thus replacement) of the forming current sheet by a chain of primary magnetic islands generated by the tearing instability. Our study is substantially different from, and more fundamental than, previous related work on the tearing
instability of reconnecting current sheets [28, 32] which
has focused exclusively on the linear evolution of a time independent current sheet and has not considered if and how the FKR regime transitions into the Coppi regime.

In contrast, we have considered a time-evolving current
sheet at an arbitrary current-sheet formation rate, computed the pertinent time scales related to various unstable tearing modes, and analyzed the order in which these various processes happen during both the linear and nonlinear evolution.

Our analysis has allowed us to predict for the first time the moment at which the current sheet is disrupted (the reconnection onset), the number of primary magnetic islands that disrupt the sheet, and the final current sheet properties at the time of disruption and elucidate their dependence on the Lundquist number and the current sheet formation drive.

In particular, our analysis reveals that two distinct regimes are possible: the FKR/Rutherford regime, in which the current sheet is disrupted by only one or two slands; and the Coppi regime, where, instead, the sheet is disrupted by a large number of islands.

Both scenarios can be relevant to experimental, astrophysical and space systems, including solar flares, where they yield reasonable estimates for flare onset time [9].


Although we have restricted ourselves to the MHD description, the conceptual framework outlined in this Letter is completely general and can be extended to collisionless plasmas provided that the linear and nonlinear regimes of the tearing instability are understood in the particular collisionless formulation that one chooses to adopt.

This is indeed necessary in order to address the
onset problem in two other prominent contexts: the saw-
tooth instability in tokamaks [48], and reconnection in
the Earth’s magnetotail [5].

http://library.psfc.mit.edu/catalog/...ja006_full.pdf

As we know the volcanism involved during large VEIs is capable of connecting the mantle to the solar output directly. But engendered magnetism has also been observed forming bipolar sheets in deep trench outflows as the magma in such vents cools below 500 C.

Don't miss this on the 22nd/23. I think it will demonstrate the relativity of plasmas. I know this stuff is difficult to follow especially if you are insistent I don't know what I am talking about.

The relationship with earthquakes, storms and volcanic eruptions equates to magnetic storms too and this is going to be demonstrated for you on Friday if you are awake to what they are playing at with their DeepState machinations.

Anyone got graphics for FKR/Rutherford regimes. Video would be favourite.
Preferably before the First Quarter which is at 16:35 an liable to be liability, but I jest need to go peepee.