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Author Topic: Discuss: Will my skin soak up the calories in skin cream?  (Read 11932 times)

Offline thedoc

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This week we find out if a liberal slathering of oil based moisturiser makes up part of our daily calorie quota. Plus we ask, are monitor screens and e.books more than your standard page turner, leaving you tossing and turning and up all night?....
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If you want to discuss this show, or ask a question, this is the place to do it.
« Last Edit: 16/04/2012 13:59:48 by _system »


 

Offline DoctorBeaver

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Re: The view from a ring singularity?
« Reply #1 on: 29/01/2006 10:55:21 »
That's quite some thought & I look forward to some learned answers & discussion on this. Hopefully some of it will be in language I may be able to follow.
 

Offline Soul Surfer

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Re: The view from a ring singularity?
« Reply #2 on: 31/01/2006 09:41:24 »
I have been doing a little more thinking about the collapse process inside a rotating black hole.

This is how I visualise it.

There will be an initial ellipsoidal  (or maybe discoidal) collapse which will become toroidal as "viscosity" drags the still center out and gives it angular momentum.  As the collapse to a ring continues residual angular momenum about the ring will cause it to rotate like a smoke ring and again the residual still centre of the torus will be evacuated. so the final stucture is a rotating toroidal membrane which allows residual angular momentum in all dimensions to be accommadated

Does anyone have information on the gravitational fields of toroidal objects or toroidal membranes?

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« Last Edit: 05/02/2006 10:22:35 by Soul Surfer »
 

Offline ukmicky

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Re: The view from a ring singularity?
« Reply #3 on: 01/02/2006 03:55:13 »
Sorry Ian but your just to damn clever for most of us.

The most most of us can do in response to your question is smile. We've got more chance of being  travoltered by a beam of light from space(What was that film) than helping you on this one .:)


Even so it's great having you on the forum answering our question's.



Michael                 HAPPY NEW YEAR                    
« Last Edit: 01/02/2006 03:56:45 by ukmicky »
 

Offline Soul Surfer

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Re: The view from a ring singularity?
« Reply #4 on: 01/02/2006 08:11:24 »
I appreciate that not many of the contibutors to this page are likely to have the knowledge and experience to help directly but they do get around the web a lot like me and the more eyes looking for a useful site where I can get more information or pose this question to a real expert the more likely I am to find one.

The administrators of this site also have reasonably current contacts into the university and may be able to introduce me to someone who is an expert who is interested in this question.

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Offline johntsang

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Re: The view from a ring singularity?
« Reply #5 on: 07/02/2006 00:46:47 »
I find your topic very interesting, and in fact offer quite a different insight of how to view the space time, the points you stated are valid !

Please post more.
 

Offline johntsang

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Re: The view from a ring singularity?
« Reply #6 on: 07/02/2006 00:52:16 »
Tell me, use your super-computer.... your brain ....

What if two such ring universes interact when they are close by ?

John Tsang
 

Offline neilep

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Re: The view from a ring singularity?
« Reply #7 on: 07/02/2006 01:14:49 »
Ian, I know you probably winced in pain when you saw that I had replied here but it's only to echo Eths and Michaels sentiments.....I've tried to keep well away from this thread.....we need GSMOLLIN and SOLVAY on this one.


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Offline Soul Surfer

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Re: The view from a ring singularity?
« Reply #8 on: 07/02/2006 22:09:11 »
Two ring singularities will occasionally clash as two rotating black holes merge there could well be a sequence of such clashes as the merge.  what might happen could be similar to some of the brane based cosmologies where the big bang came from a mentary clash of two multidimensinal membranes.

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Offline johntsang

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Re: The view from a ring singularity?
« Reply #9 on: 08/02/2006 01:48:02 »
How about the direction of rotation, what happen if one of it is up and the other is down, and getting close by, would they expulse each other in some form ?
 

Offline ukmicky

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Re: The view from a ring singularity?
« Reply #10 on: 08/02/2006 02:29:13 »
I would love to see what would happen if two evenly matched blackholes colided with each other head on at speed. Could a singularity be destroyed and spew its guts into space

Michael
« Last Edit: 08/02/2006 03:16:48 by ukmicky »
 

Offline Soul Surfer

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Re: The view from a ring singularity?
« Reply #11 on: 08/02/2006 08:52:28 »
No they should just form a bigger black hole any spectacular stuff will be hidden behind the event horizon

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Offline johntsang

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Re: The view from a ring singularity?
« Reply #12 on: 08/02/2006 09:37:42 »
Is there any configuration of materail structure, in any form of rotation would create an expulsion effect?

I would guess things link Saturn ring would create somewhat a repulsion  effect on another planet with a reverse turning ring, say distributed more evenly in great space arount the planet ...

And rotating torus BH may be ????
 

Offline johntsang

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Re: The view from a ring singularity?
« Reply #13 on: 08/02/2006 09:43:50 »
And I suspect a rotation Hole would have a draft in gravitation , more or less in spiral form around it's surrounding space that any matter getting close would be dragged 'sideway' while it more down the hole.

Moreover, if tow such hole gstting together, and it's rotation axis is reverse, the effect should be more fun than just dropping into each others .....
 

Offline Soul Surfer

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Re: The view from a ring singularity?
« Reply #14 on: 08/02/2006 21:15:43 »
The centrifugal force that comes from the angular momenum and the attracrion due to gravity is the expulsion effect but it is exactly baanved over the orbit.

Kook up Kerr black holes for more details of the standard theories.  what I am talking about does not go against these in any way it just looks in much more detail at the process of the material that is collapsing towards forming the singularity as it collapses over a signoficant period of time

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Offline johntsang

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Re: The view from a ring singularity?
« Reply #15 on: 09/02/2006 00:22:18 »
I should clarify my question, the ditribution of material in space around the hole, carries energy, in the form of angular momentum, could be exchange while the two hole / celestrial body approaching, in case of dense distribution, and when the bodies are quite far from each others.

Could there be a point when this exchange overcome the gravitaion ?


 

Offline johntsang

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Re: The view from a ring singularity?
« Reply #16 on: 09/02/2006 00:26:24 »
Of course, I should carry out some calculation to find out.

However in space observation, when two spiral galacy collide,  would they pass thru each others directly without any effect of expulsion ? I shall take a look.
 

Offline johntsang

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Re: The view from a ring singularity?
« Reply #17 on: 09/02/2006 02:22:32 »
Sorry to post some quote here, could be related: universetoday.com/am/publish/podcast_galactic_exiles.html?2712006

Dr. Warren Brown: What we discovered are two stars in the far out regions of the Milky Way that are traveling at speeds that no one has ever really seen stars in our galaxy, at least stars outside of the galactic centre. Except that these stars are hundreds of thousands of light years away from the galactic centre. And yet, the only plausible explanation for their velocity is that they were ejected by the supermassive black hole at the centre of the galaxy.

Fraser: So they strayed too close to the supermassive black hole and were kind of kicked out?

Brown: Yeah, so here's the picture. This scenario requires three bodies, and astronomers say that the most likely way that it happened is if you have a pair of stars. As you may be aware, something like half the stars in the sky are actually systems containing a pair, or sometimes more stars. And so if you have a tightly bound pair of stars that, for some reason, travel too close to the supermassive black hole, at some point the black hole's gravity will exceed the binding energy between the pair of stars and rip one of those stars away. It'll capture the one star, but the other star then leaves the system with the orbital energy of the pair. And that's how you get this extra boost of velocity. It's that the supermassive black hole is basically able to unbind one star, capture it, and leave the other one with the entire amount of energy that the pair used to have. And that star then gets ejected right out of the galaxy.
 

Offline tony6789

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Re: The view from a ring singularity?
« Reply #18 on: 09/02/2006 14:26:38 »
You lost me at about the fourth paragraph soul can u simplify it pls?

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Offline johntsang

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Re: The view from a ring singularity?
« Reply #19 on: 09/02/2006 15:54:01 »
basically what it means is , due to the conservation of angular momentum, when a particle drops further into a Gravitation center, then some other particle must eject outward, and generate a repulsion effect.
 

Offline johntsang

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Re: The view from a ring singularity?
« Reply #20 on: 10/02/2006 01:48:21 »
On the otherhand , think from the point of those particles on the ring singularity inside a rotating black hole, it would seem like he's in 4 dimension space, whereas one of the axis is at the speed of light .... don't you think so ?
 

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Re: The view from a ring singularity?
« Reply #21 on: 10/02/2006 02:22:39 »
quote:
Originally posted by ukmicky

I would love to see what would happen if two evenly matched blackholes colided with each other head on at speed. Could a singularity be destroyed and spew its guts into space

Michael



quote:
Originally posted by Soul Surfer

No they should just form a bigger black hole any spectacular stuff will be hidden behind the event horizon

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I can see why you would say this, but what happens to the kinetic energy?

Internally, it would no doubt simply create a lot of heat, but would you not get a violation of the conservation of energy unless we could somehow see that kinetic energy do something outside of the black hole?  Will all that kinetic energy be converted to mass (i.e. the mass of the two coalesced black holes exceeding the sum of the individual masses of the black holes)?
 

Offline Soul Surfer

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Re: The view from a ring singularity?
« Reply #22 on: 10/02/2006 19:54:39 »
You've pretty well argued it out yourself.  The big point is that if you have a true point singularity the potential energy that can be turned into kinetic energy is without bound  but we only see the bit outside the event horizon.

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Offline DoctorBeaver

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Re: The view from a ring singularity?
« Reply #23 on: 18/02/2006 19:22:51 »
Ian - I've got a question about the particles. You say you expect their motion to settle down into fractal spirals. If the angles between all the particles remained constant (i.e. their motion & speeds were constant, or changing at a consistent rate), I can see that the visual effect would be similar to that of "normal" spacetime. But would that happen?  To maintain a stable orbit, wouldn't the particle's distance from the centre determine its speed?
Take the example of a solar system. If all the planets were identical & by some fluke started off all lined up away from the sun, would they stay lined up with identical periods of orbit (as if stuck on the surface of a disc), or gradually move "out of phase"?
I've heard the analogy comparing the effect of a rotating black hole on spacetime with a whirlpool's effect on water. The water near the centre is moving much faster than that at the outer limit. Spacetime nearer the centre of a rotating blackhole would similarly be pulled around much faster. If the singularity was toroidal, the effect would, surely, be even more pronounced. If that were the case, then the effect would be totally different from what we see in the universe. Not all objects at the extremes of detection would be moving away as we would gradually be catching up with those that were ahead of us in their orbit; much in the same way as Earth catches up & passes planets that are further from the sun.
 

Offline Soul Surfer

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Re: The view from a ring singularity?
« Reply #24 on: 21/02/2006 23:07:47 »
I think the ring singularity would form a toroidal surface like the surface of a ring doughnut very thin and dense with the main gravitational forces normal or perpendicular to the surface and the angular momentum in each of the directions defining the size of the main ring and the loop as the particles cooled down they all end up at very similar velocities  their orbital velocity is such that it is extremely close to the velocity of light

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Re: The view from a ring singularity?
« Reply #24 on: 21/02/2006 23:07:47 »

 

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