Would magn. pole reversal actually mess up electronic equipment?
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From: John Fields on 5 Jan 2010 13:27 On Tue, 05 Jan 2010 12:16:48 +1100, Sylvia Else <sylvia(a)not.at.this.address> wrote: >John Fields wrote: >> On Fri, 01 Jan 2010 21:36:18 +1100, Sylvia Else >> <sylvia(a)not.at.this.address> wrote: >> >> >>> Objects at different distances from the centre of the galaxy will have >>> different orbital periods. The time the Earth takes to go around the >>> galaxy will be different the time other objects take. There is no reason >>> to deem that the Earth's orbital period is the period of rotation of the >>> galaxy, and since different objects have different periods, the galaxy >>> does not have a rotational speed. >> >> --- >> Surprise!!! :-) >> >> http://en.wikipedia.org/wiki/Galaxy_rotation_curve >> >> JF > >No - they still have differing orbital periods, even though they move at >about the same velocity, because those further out have further to >travel to make one orbit. --- Agreed; good point. However, what remains is that the velocity of the objects a little way out from the hub and all the way out to the rim is nearly constant, which is anomalous and flies in the face of Newton's universal law of gravitation. JF
From: Rich Webb on 5 Jan 2010 15:06 On Tue, 05 Jan 2010 12:27:59 -0600, John Fields <jfields(a)austininstruments.com> wrote: >On Tue, 05 Jan 2010 12:16:48 +1100, Sylvia Else ><sylvia(a)not.at.this.address> wrote: > >>John Fields wrote: >>> On Fri, 01 Jan 2010 21:36:18 +1100, Sylvia Else >>> <sylvia(a)not.at.this.address> wrote: >>> >>> >>>> Objects at different distances from the centre of the galaxy will have >>>> different orbital periods. The time the Earth takes to go around the >>>> galaxy will be different the time other objects take. There is no reason >>>> to deem that the Earth's orbital period is the period of rotation of the >>>> galaxy, and since different objects have different periods, the galaxy >>>> does not have a rotational speed. >>> >>> --- >>> Surprise!!! :-) >>> >>> http://en.wikipedia.org/wiki/Galaxy_rotation_curve >>> >>> JF >> >>No - they still have differing orbital periods, even though they move at >>about the same velocity, because those further out have further to >>travel to make one orbit. > >--- >Agreed; good point. > >However, what remains is that the velocity of the objects a little way >out from the hub and all the way out to the rim is nearly constant, >which is anomalous and flies in the face of Newton's universal law of >gravitation. Not necessarily. When we run across anomalies between predicted and observed, the choice usually comes down to "our understanding of gravity is incomplete" or "there's something else out there." Observations of perturbations in the orbit of Mercury, for example, pretty much had the smart money betting on the "something else" theory (Vulcan) but the right answer turned out to be "incomplete understanding of gravity" (GR). Some discussion (and a pretty picture) over at <http://blogs.discovermagazine.com/cosmicvariance/2007/11/01/dark-matter-still-existing/> although there's still quite a lot of room for legitimate "Yes, but ..." refutations. -- Rich Webb Norfolk, VA
From: John Fields on 5 Jan 2010 20:16 On Tue, 05 Jan 2010 15:48:21 +1100, Sylvia Else <sylvia(a)not.at.this.address> wrote: >John Fields wrote: >> On Sun, 3 Jan 2010 07:31:18 -0800 (PST), MooseFET <kensmith(a)rahul.net> >> wrote: >> >> . >> . >> . >> >>> You are correct that the motions are relative to other bodies and not >>> relative to some >>> mythical fixed frame of reference in space. We are part of a group at >>> appears to be >>> gathering together amidst the greater collection that is flying apart. >> >> --- >> Which leads to my favorite hypothesis; that there was no big bang, but >> rather a big bubble which came about much like a bubble appears in a >> cavitating medium. >> >> If that were the case, then the medium surrounding our bubble would be >> the Universe, while what was bounded by the walls of our bubble would be >> our universe. >> >> Looking at it from the point of view that matter is accelerating away >> from us as its distance from us increases makes no sense in a big bang >> universe since, after the initial acceleration, nothing would be driving >> the mass and one would expect that matter would either recede at a >> constant velocity if the universe was open, stop if the universe was >> static, or accrete if the universe was closed. >> >> Such is not the case however, and for matter to accelerate as it gets >> farther way from us requires that some force be attracting it. > >I think you have the roles of reality and theory reversed. The universe >behaves in some way. It is not constrained by theory. The role of theory >is to model the behaviour of the universe. On reasonably local scales, >theories involving force, mass and acceleration provide accurate >predictions of the behaviour of matter. But that's as far as it goes. If >the large scale Universe is found to be behaving in a way that is >inconsistent with the theory, then the theory has to be modified. You >can't argue that the Universe must take some form because the present >theoretical model requires it. --- Nor have I. The reality is that galaxies are receding from us at velocities which increase as their distances from us increase, and that they're accelerating, while the theory is that that can't happen because there's no gravitational force which can power the acceleration if the universe started with a big bang. Consequently, my argument was, and is, that since the creation of a universe from a putative "big bang" cannot explain the anomalous acceleration of galactic red shift with distance, then perhaps there was no big bang, but rather a big bubble at the beginning of time which does allow galactic red shift acceleration with distance. Do you have a better idea? JF
From: life imitates life on 6 Jan 2010 00:27 On Tue, 05 Jan 2010 14:42:34 GMT, zekfrivo(a)zekfrivolous.com (GregS) wrote: >In article <00a0d326$0$16928$c3e8da3(a)news.astraweb.com>, Sylvia Else <sylvia(a)not.at.this.address> wrote: >>John Fields wrote: >>> On Fri, 01 Jan 2010 21:36:18 +1100, Sylvia Else >>> <sylvia(a)not.at.this.address> wrote: >>> >>> >>>> Objects at different distances from the centre of the galaxy will have >>>> different orbital periods. The time the Earth takes to go around the >>>> galaxy will be different the time other objects take. There is no reason >>>> to deem that the Earth's orbital period is the period of rotation of the >>>> galaxy, and since different objects have different periods, the galaxy >>>> does not have a rotational speed. >>> >>> --- >>> Surprise!!! :-) >>> >>> http://en.wikipedia.org/wiki/Galaxy_rotation_curve >>> >>> JF >> >>No - they still have differing orbital periods, even though they move at >>about the same velocity, because those further out have further to >>travel to make one orbit. >> > > >I was wondering why most things rotate inline bunched up, around the axis in the same direction. >What starts this process ? > >greg Huge gasses and huge masses getting slammed outward at near the speed of light (beginning of 'time and space and matter')... as gravity begins to make them clump and glom together on their way outward, they swing past each other and set up "spins". Make some fresh tea after heating the water up 'real good' in the microwave so it makes a nice foam and then stir it, and then perturb the flow such that it still spins but not quite perfect, then observe the bubbles. It is all in the tea... life imitates life. Chaos rules as far as the universe goes. Weather simulators do a fine job with it, and that link the guy posted this morning has some REALLY COOL videos on it.
From: The Great Attractor on 6 Jan 2010 00:30
On Tue, 05 Jan 2010 12:21:23 -0600, John Fields <jfields(a)austininstruments.com> wrote: > leave our universe, and become part of The >Universe. The non-capitalized, and Capitalized version here tells it all. That it is, in a nutshell. :-P A BIG nutshell I agree with you... there is another 'somewhere' 'out there'. |