sci.physics.relativity

Hi Sue,
This is a good thread and I wish
to stay on topic.
so let me put you on hold pending
the replies of others, with all due
respect.
Ken S. Tucker


On Feb 20, 1:07 pm, "Sue..." wrote:
> On Feb 20, 3:31 pm, "Ken S. Tucker" wrote:
>
>
>
> > On Feb 20, 12:10 pm, "Sue..." wrote:
>
> > > On Feb 20, 2:03 pm, "Ken S. Tucker" wrote:
>
> > > > Hi Edward and all.
>
> > > > On Feb 14, 7:11 pm, Edward Green wrote:
>
> > > > > On Feb 14, 1:38 am, Eric Gisse wrote, in part:
>
> > > > > > There are NO interior solutions to Kerr in general relativity to my
> > > > > > knowledge. That raises a red flag - I don't believe it is proven they
> > > > > > don't exist, but it's suggestive to me.
>
> > > > > Yes, to me too.
>
> > > > > I had intended to ask whether "interior solution" means interior to
> > > > > the event horizon or interior to a surface within which the vacuum is
> > > > > replaced with a mass density. It turns out, on some investigation,
> > > > > both!
>
> > > > > The vacuum solution inside the event horizon is said to be "unstable",
> > > > > whatever that means, or else "unphysical" (that part of a respectable
> > > > > theory which in lesser theories might be described as "wrong"). I also
> > > > > learned, as you say, that there is no known solution including mass
> > > > > density which can be smoothly joined to the outer Kerr solution
> > > > > (although some treatment of a spinning dust disk reduces to Kerr
> > > > > solution in a limiting case).
>
> > > > > The evidence is firmly ambiguous: if we could show no non-vacuum
> > > > > extension of the solution were possible inward, then I think we could
> > > > > safely say that the hope that Kerr describes the exterior field of a
> > > > > massive spinning body is doomed; however, the language is "not known"
> > > > > -- and there is the tantalizing datum of a single known solution is a
> > > > > single special case.
>
> > > > > I am tempted to claim that the exterior vacuum Kerr solution, while a
> > > > > valid solution of the field equations, cannot represent the external
> > > > > field of a spinning body. As I mentioned, a rotating massive object
> > > > > seems to transmit no intelligence of its sense of rotation to the GR
> > > > > source term. If we are in fact able to tell from purely gravitational
> > > > > observation which way a spheroid is spinning, then there must be some
> > > > > additional factor which breaks the symmetry.
>
> > > > I agree, because the Guv=Tuv is symmetrical,
> > > > furthermore I think AE made a mistake in Ch2
> > > > of this ref,
>
> > >/gallery/pdf/CP6Doc30_English_pp146-200...
>
> > > > AE has S1 a as sphere and S2 as an ellipsoid,
> > > > then he relies on Mach's *principle* to
> > > > justify the differing shapes, (something
> > > > about rotation) but it's unnecessary in GR.
>
> > > A page number would be helpful.
>
> > > Hmmm...
>
> > > These molecules are ~ellipsoidal~
>
> > >/gchelp/liquids/
>
> > > but a cloud of zillions of them acting as an inertial
> > > background (Machian) would exert even force and
> > > so a test mass would be spherical.
>
> > > > The internal "stress-energy" tensor shapes
> > > > differences work quite well, for example see,
>
> > >/wiki/Piezoelectricity
>
> > > > If S1 is composed of a Piezoelectrical
> > > > crystal, with no interior voltage diffs,
> > > > but S2 has interior voltage diffs to
> > > > force the sphere into a ellpsoidal shape,
> > > > as in the wiki ref, where the North and
> > > > South Pole are pushed together, the
> > > > reciprocal effect is to apply a voltage
> > > > and vary the geometry, as a smoke detector
> > > > squeaker does.
>
> > > > As Edward points out,(and I agree),the
> > > > fact of an ellpsoidal shape does NOT
> > > > provide any direction of rotation into
> > > > the g-field, and there is no need to
> > > > presume rotation is the cause of the
> > > > ellipsoid.
>
> > > That may be the case for you piezoelectric analog
> > > but but the mechanism Koruopolis describes
>
> > > --Koruopolis/abs/physics/0107015
>
> > > DOES have a directed orientation along the lines of force.
>
> > > Sue...
>
> > > > Regards
> > > > Ken S. Tucker
> > > > [snip]- Hide quoted text -
>
> > > > - Show quoted text -
>
> > Our Mr. Green is surveying an object
> > and finds it is an ellipsoid.
> > Now how can Mr. Green find the direction
> > of rotation of said ellipsoid?
>
> A ~Machian~ backgroud does not have a direction
> however a pair of molecules interacting as
> as induction partners has a direction wrt
> each other.
>
> For pairs of hydrogen:
>
> +- -+ Repelling, unstable
>
> -+ -+ Attracting, stable
>
> +- +- Attracting, stable
>
> I suppose you could say the directions are
> inward and outward.
>
> <<... unlike the case of Newtonian mechanics, we have to
> be careful about the presuppositions of such a
> coordinate system, since in general relativity various
> reference frames are possible and allowed. How should
> we choose axes of a coordinate system, and how should
> we obtain a value on such an axis? >>/~suchii/
>
> Sue...
>
> > Regards
> > Ken S. Tucker