[yor_on]

That is also a nice one Murchie. Made me think, but, if we assume a exact 'middle point' inside a spinning object would that points motion really form a ring?  As seen from the outside, assuming we could see it, being stationary relative the spinning object, it would certainly spin, but why would it assume a ring? Tidal forces?? And even if I assumed it would do so, wouldn't it still create yet another center 'inside' it? As a 'ring' always will have a center of its own, just like a wheel. Or maybe you meant it some other way that I miss?

[graham.d]

Yor_on, a zero field in the centre of a spherical shell is only zero because, even classically, because the integrated sum of all the vector components from all parts of the shell exactly cancel. When the shell starts moving, and the distances to each of these parts change, the finite time it takes for a test body to feel the influence of these movements will not generally be perfectly balanced. The changes in field are propagated as a gravitational wave at lightspeed, but as far as a thought experiment goes, you can just think of the test body only seeing the movement and feeling the field change after the time it takes (on his local clock) for the information to reach him.

[Murchie85 (OP)]

According to Micheo kaku, at the centre of spinning black holes is an eye, like the eye of a storm with the matter swirling around it, its a relatively new proposal.

Yes according to newtonian equations if you equate the field by integrating the parts then the vectors will cancel, although part of the question would be "is this really an accurate description of reality? (gravity)"

[yor_on]

Nice Murchie, it then becomes our idea of geometry against?
And this eye wouldn't then have a center?
==

Yeah, but with a perfect sphere Graham?
Would they still be unbalanced?

Either we have one, or we don't

[Geezer]

Yeah, but with a perfect sphere Graham?
Would they still be unbalanced?

It might be balanced at first, but I'm guessing it would be unstable, so it would not take long to go out of balance.
Wonder if I guessed right?  []

[yor_on]

Well, then it won't be a perfect sphere will it?


But sh*, I don't know either
It's like Murchie said.
Is it an accurate description of 'reality'?

[Geezer]

Well, then it won't be a perfect sphere will it?

True. But like they say, "No body is perfect".

Sorry for that! But, in fact, it's probably true. It's more about the stability of the system. A system that is "perfectly" balanced but intrinsically unstable will disintegrate in no time. Noise will guarantee it, and there is no escape from noise.

[Frodeborli]

If all mass and energy was at one point in time concentrated at one spot, isn't it symmetrical then? If it suddenly explodes (Big Bang), it would still be perfectly symmetrical - since nothing "outside" can destabilize the symmetry...

[yor_on]

It's all about geometry, one way or another.
Either the geometry and ways we use are correct even if 'plastic' and then you should be able to define a center even to a black hole. Or we don't really know how it is working and as Murchie wrote. "According to Micheo kaku, at the centre of spinning black holes is an eye, like the eye of a storm with the matter swirling around it, its a relatively new proposal."

Now, if that is correct then where did the geometry go?
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Rereading the citation, maybe he don't question a center, just propose a still area around it?

But I agree Frodeborli, there is nothing wrong in imaging a perfect symmetry, although, most everything we observe won't have it.