Bluemoon

Do you think, though, that the distubances of the Coulomb field of a charge travel superluminaly {as the authors claim] ?

Only that the actual [relativistic, "γ ≈ 1000" and limited to c] speeds are nigh-on unaltered for all of the accelerator's output range, compared to what Newton would have expected; though [reading between your lines] I can't see how that may impact on whether or not the "Coulomb field [is] carried rigidly by the moving charge".

Harmful content? Let me guess again: You think that the paper's authors' conclusions do not contradict the foundation assumptions of relativity theory; yes - ?

Do you mean that you think that if the source moves that its associated field (at all distances from it) does not change at the same instant?

I've just discovered the paper Measuring Propagation Speed of Coulomb Fields (PDF) which appears to show that the Coulomb field (& also gravitational fields) travel with infinite speed. The authors also dismiss a critique of their research here (PDF). The theory is way over my head, so I am wondering what the views are of the better educated on S.F as to the merit of the authors' conclusions.

Thanks for that practical suggestion Edwina Lee, I had intuitively thought that keeping everything spinning at equal speeds to be the best starting point as I, too, don't have the brain for a full analysis.

True, but: I idealised it to a sphere as I thought that that would be more analytically tractable though still keeping the molten chocolate. Yes. swansont: I only used the phrase in-turn in the physical sense to describe the mechanical structure [not the temporal sense]; I had supposed that the chocolate would be affected the same way regardless of the phasing of the gimble spins because as I see it: the rotations, when considered as framed in my OP, are commutative; each axis/(gimble)/rotation is defined relative to another (rather than per the convention) i.e: the y-axis/(gimble) sits in the z-axis/(gimble); and the x-axis/(gimble) sits in the y-axis/(gimble) and the sphere spins on that x-axis; and so: the orientation of the sphere after defined rotations of each of Those z, y & x axes/(gimbles) will not depend on the order of their execution.

It was an oversight but I should have stated the context to be that all of the axes/gimbles rotate with the same angular velocity. However: why should non-commutativity preclude an analysis? Although rotations can not be said to be be generally commutative, the sphere, none-the-less, spins; so surely that can be analysed? Anyway, I did some brief numerical analysis by hand and it seemed that the chocolate does just slosh about. steveupson: that's a wonderful resource {+1; although each video froze my old laptop for a, Very, long time; the whole lot took me over 4 hours to watch}. The 4D lecture reminded me of the Charisma Cleo video editor [made by Questech but neither still exist] which was popular with broadcasters in the 1990s. It would roll-up a 2D screenshot into an apparent sphere (or paper-dart or any other of a large selection of pre- or user- programmed 'objects') revealing the next camera shot behind it, the spherical image would then roll off into the 'distance'. I never knew but I now presume that Quaternions would have been the core tool of the algorithm in the processor [which was specified as a 'tailored' supercomputer](?)

Can anyone please tell me: in what direction does a point on the surface of a sphere accelerate when: the sphere is spun on an axis which is in-turn spun on an axis orthogonal to the first and that 2nd axis is spun on an axis orthoganal to the previous two: This relates to a brief discussion that I had with someone about the moulding of Easter eggs(!) Would the chocolate just slosh about or does it all get uniformly pressed to the inner surface of the sphere?

I now don't think that my question was aswerable. It looks like the whole issue of the Earth's charge is very much more complex than I ever imagined:- en.wikipedia.org/wiki/Atmospheric_electricity

elfmotat >" So Earth will start accumulating more negative charges ... " From where though? RE: OP:- " ... so what is the source of the electrons that offset this embedded Cosmic ray charge and how do they arrive? " Sensei What part of the OP:- " However, the Earth appears to have no net charge ...." is an invitation to post your Selfie ? Fuzzwood >" Also: http://en.wikipedia...._radiation_belt " ... and .... ? ! Enthalpy > ".. the solar wind, whch I'd say is the biggest contributor - if it's not the ionization of the upper atmosphere ..." Do they diffuse down or occasionaly discharge down as lightning? What of the Cosmic Ray sources? The surface flux on Earth is ~1000/sqm/s. I make that a charge of 80mC/s impacting over the Earth's surface ---> ~2.5MC/year and that's just the Earth! Over the Solar system or maybe the galaxy then something somewhere is surely getting Very negatively charged?

The Wikipedia article for Cosmic ray { http://en.wikipedia.org/wiki/Cosmic_ray} says that they are mostly positively charged and that electrons (beta particles) constitute about 1% of galactic cosmic rays. The ones that impact on the earth's rocky surface must remain trapped inside it forever. However, the Earth appears to have no net charge, so what is the source of the electrons that offset this embedded Cosmic ray charge and how do they arrive? Also, is it likely to be so that whatever the sources are of Cosmic rays, that they must, after 13 billion years, now have an enormous -ve charge; or that the positive partners to Earth's neutralizing electrons drift across space to neutralize that source (presumably after radiativley spiraling in).

Confidence in this project may explain the following directive by the US Senate issued in July :- "the Committee directs the Department of Energy to work with the Department of State to withdraw from the ITER project" https://en.wikipedia.org/wiki/ITER

Acme, your wiki link is intersesting, 60% is nearly plausible, but ... Strange >What proportion of UK power stations run on kerosene? Good point, I've only been able to find one:- Peterhead Power Station in Scotland which, presumably, must be because Kerosene/heating oil really are as expensive as I thought making my query mute. swansont >Do power stations sell all of their electricity at wholesale rates? I think so, because sometime last year SSE were told by the regulator that they had to stop selling theirs directly to their customers and instead sell it wholesale to the 'pool' and then buy/(bid for) it back as a 'pool' customer; and only then be able to sell it on to their customers. Otherwise if they wanted to they would even be able to profitably sell the oil-made stuff, 5p +60% = 8.4p, to the likes of me for the 12p that they do; (but they add some extras on, one of which is profit, that brings the price up to 16.5p +vat).

I suppose that it's burnt in a furnace.