A question?

It would appear to stand still.. right before it disintegrated. If the particles were still in motion.. inertia.. they would swirl out at different lengths due to their mass.

Arbitrageur
f you're talking about relativistic contraction in the direction of linear motion, isn't that dependent on the observer's frame of reference? In other words, an observer on or in the spinning disk wouldn't see the contraction due to linear motion that an external observer would observe.

If it's a rotating sphere, what is an observer's viewpoint on the thing? There's such a gradient of temporal distortion, relativistic contraction and whatnot that you'd likely be hard put to find a consistent internal frame of reference. Unless the diameter was very large.

Bedlam

Arbitrageur
f you're talking about relativistic contraction in the direction of linear motion, isn't that dependent on the observer's frame of reference? In other words, an observer on or in the spinning disk wouldn't see the contraction due to linear motion that an external observer would observe.

If it's a rotating sphere, what is an observer's viewpoint on the thing? There's such a gradient of temporal distortion, relativistic contraction and whatnot that you'd likely be hard put to find a consistent internal frame of reference. Unless the diameter was very large.

Basically another way to look at this concept, is that at a certain point in increasing the angular momentum of earths rotations things would start flying off of it? And then eventually it itself, the energy of its rotation would surpass the energy that binds the matter and it itself would come apart? But that is only the case with starting at one speed and accelerating, if it just popped into existence stabley rotating at high speeds couldnt it stay intact? Maybe it would also depend where the energy causing the rotation was coming from, if it was coming from the core or coming from outside of the sphere. Like an ice skater who spins and draws them self in and spins faster or a top, there is some kind of arc relationship between stability and a threshold surpassing with angular momentum to anti stability.

reply to post by ImaFungi


More, for a comparatively small sphere with a boundary rotational velocity approaching C, you have a huge gradient of relativistic behaviors varying from profound at the outer edge to zero at the axis.

Bedlam
If it's a rotating sphere, what is an observer's viewpoint on the thing? There's such a gradient of temporal distortion, relativistic contraction and whatnot that you'd likely be hard put to find a consistent internal frame of reference. Unless the diameter was very large.

ImaFungi mentioned a galaxy in the original question which is more of a disk so I'll use that as it's easier to address a disk than a sphere. Mount some laser rangefinders located at the disk axis pointed in various directions to the disk edge. Since they are moving along with the disk, they will not see a contraction of the disk in one direction due to linear movement that an outside observer would observe. The laser rangefinders should observe radial symmetry, shouldn't they?

Arbitrageur
The laser rangefinders should observe radial symmetry, shouldn't they?

One delta in, though, is a different reference frame. It should see a contraction...

reply to post by Bedlam

Are you talking about radially symmetrical contraction?

The reason I ask is because you were talking about the disk rigidity and I didn't really get where you were going with that.

Arbitrageur
reply to post by Bedlam

 

Are you talking about radially symmetrical contraction?

The reason I ask is because you were talking about the disk rigidity and I didn't really get where you were going with that.

It should be. An infinitely rigid disk wouldn't allow rotation due to the contraction. Whenever someone asks about spinning objects with relativistic outer velocities I think of that paper and Tipler's paper on closed time-like paths.

Bedlam
reply to post by ImaFungi

 

More, for a comparatively small sphere with a boundary rotational velocity approaching C, you have a huge gradient of relativistic behaviors varying from profound at the outer edge to zero at the axis.

And that zero at the axis is why black holes are 'infinitely dense'? Or at least the outer edge of a black hole is the event horizon compared to the inner point which is the axis of the entire galaxy? So like this conversations topic is one of the reasons dark matter was agreed upon, because the galaxy is a rotating disk of sorts and it is rotating at a velocity that should separate its shaped parts? So if we imagine the 2d gravity well descriptions used and imagine a fabric in which 4 people are grabbing the 4 corners, and 1 person grabs underneath in the center and pulls the center down while the others remain at their height, and they throw a bunch of marbles in that start swirling around the center, in reality the way it would be like a galaxy would be if all members holding would equally rotate, as well as traveling in some linear direction, the question is why dont the marbles ramp off the surrounding gravity slope like a launch ramp, because the mass calculated was not enough to keep a ramp that would hold the marbles from launching. I know youve heard me try and say it before, but 2 solution's I thought of are that the space gravity ramp, the outer edge of it, is an energetic barrier of medium, which has momentum and force, and it is rotating and traveling linear, all entire circular edge, and this force of its travel through outergalactic space time reacts with that outergalactic space time in a way that it creates a wave, not a little one but perhaps a constant tsunami at the edges, like a rip tide, which compels matter at the edges inward, which is what the entity of the galaxy does anyway, acts like a giant rip tide from the center, compelling the matter more outer, inward. The other thought I had maybe is gravity not imagined as a 2d surface, but as the 3d medium it is, has therefore extra energy components; like we can imagine a stream of water carrying a floating object down stream, but if if there was also the same stream or slightly of different velocity flowing above the object in the same direction touching it as well, this I believe must be the nature of gravity, its weird to think of that scenario because of gravity, but gravity is the giver of those 'normal' circumstances, but gravity itself is not affected by gravity is it? Or actually it must be in at least one way,but any, I think imagining gravity 3d(4d) might be helpful in solving galaxy rotations, and understanding gravity in general, because thats how it exists. Instead of a ramp that matter can launch off, its now a curved ceiling and wall, with a compelling rotational stream that would force an object that hits it to enter along with its trajectory, and then the pull becomes a push, and the spiral spirals.

ImaFungi

Bedlam
reply to post by ImaFungi

 

More, for a comparatively small sphere with a boundary rotational velocity approaching C, you have a huge gradient of relativistic behaviors varying from profound at the outer edge to zero at the axis.

And that zero at the axis is why black holes are 'infinitely dense'?

No. The OP is about a fictional sphere with a rotation rate sufficient to leave the periphery deep in relativistic phenomenon land. Not a black hole.

reply to post by Bedlam


The fictional sphere occupies space and time in fiction and as does a black hole in reality.

How could rotation at 99.999999% the speed of light result in implosion?

Any thought?

In relation to stellar density how is period of rotation in general related to?

Comparing Sol to a neutron star as an example?

Achieving infinite density means reaching the speed of light and even in relation to a rotation.

Any thoughts?

Kashai
reply to post by Bedlam

 

The fictional sphere occupies space and time in fiction and as does a black hole in reality.

So do puppies and ice cream sandwiches.

Kashai
Any thoughts?

I think I got a nice bottle of Zinfandel last night, and that with some cheese, maybe a handful of grapes and some of those hard crackers I have in there would go really good together right about now.

reply to post by Bedlam


You really should try some Guava and Crème Cheese with a sweet Vermouth

reply to post by Kashai


Experiments are proceeding as we speak. So far, the evaluation of Project Zinfandel is positive.

reply to post by Bedlam



Rotating a mass near or at the speed of light should result in an implosion and for the record black holes are considered to have infinite density.

Any thought?

reply to post by Bedlam


With the Guava and Crème Cheese you would probably want to go with a Cracker rich in butter.

Kashai
reply to post by Bedlam

 

Rotating a mass near or at the speed of light should result in an implosion and for the record black holes are considered to have infinite density.

Maybe. It depends on whether a black hole has a radius, I suppose.

Any thought?

Zinfandel is ok but I like shiraz or merlot better. Not that there's anything wrong with this one. It's just a bit sweet for me. I like wine a bit dry.

reply to post by Bedlam


Myself a dry wine is excellent for a meal but when it comes to sweets a sweet wine, I feel, accents the moment.