50 Billion Suns! -The Biggest Single Object in the Universe !

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Offline neilep

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50 Billion Suns! -The Biggest Single Object in the Universe

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Scientists have determined the mass of the largest things that could possibly exist in our universe.  New results have placed an upper limit on the current size of black holes - and at fifty billion suns it's pretty damn big.  That's a hundred thousand tredagrams, and you'll never get the chance to use that word in relation to anything else.

Black holes are regions of space where matter is so dense that regular physics just breaks down.  You might think physical laws are immutable - you can't get out of gravitational attraction the same way you can get out of a speeding ticket - but beyond a certain level laws which determine how matter is regulated are simply overloaded and material is crushed down into something that's less an object and more a region of altered space.

While there's theoretically no upper limit on how big a black hole can be, there are hard limits on how big they could have become by now.  The universe has only existed for a finite amount of time, and even the most voracious black hole can only suck in matter at a certain rate.  The bigger the black hole, the bigger the gravitational field and the faster it can pull in matter - but that same huge gravitational gradient means that the same matter can release huge amounts of radiation as it falls, blasting other matter further away.

Based on this self-regulating maximum rate, scientists at the Harvard-Smithsonian Center for Astrophysics, Massachusetts, and the European Southern Observatory, Chile, have calculated an upper limit for these mega-mammoth masses.  Fifty billion suns, that's 100 000 000 000 000 000 000 000 000 000 000 000 000 000 kg, otherwise known as "ridiculously stupidly big" and triple the size of the largest observed black hole, OJ 287.

There are potential problems with this calculation.  Based as it is on the radiation outflow from a black hole, new discoveries could change this estimate - though only from "insanely massive" to "ridiculously ginormous."

Source: the Daily Galaxy
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Offline syhprum

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« Reply #1 on: 13/03/2009 20:58:54 »
What would that be in elephants or blue whales, the normal units for awfully big things?
syhprum

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Offline Chemistry4me

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« Reply #2 on: 14/03/2009 01:45:46 »
Will we disappear into it?

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Offline DoctorBeaver

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« Reply #3 on: 14/03/2009 10:56:05 »
Quote
...otherwise known as "ridiculously stupidly big"

 [:D]

Is that blackhole bigger than J-Lo's bottom?
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Offline Chemistry4me

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« Reply #4 on: 14/03/2009 10:58:22 »
Will we disappear into it? [:D]

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Offline DoctorBeaver

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« Reply #5 on: 14/03/2009 12:00:43 »
Will we disappear into it? [:D]

Did you ask again because no-one answered you the first time?
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Offline Chemistry4me

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« Reply #6 on: 14/03/2009 12:03:02 »
No.

It was a reply to:

Is that blackhole bigger than J-Lo's bottom?

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Offline DoctorBeaver

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« Reply #7 on: 14/03/2009 12:27:48 »
Ah, I see. You tried to make a joke.
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Offline neilep

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« Reply #8 on: 14/03/2009 12:54:02 »
What would that be in elephants or blue whales, the normal units for awfully big things?

A lot of blue whales and even more elephants !
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Offline neilep

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« Reply #9 on: 14/03/2009 12:55:07 »
Will we disappear into it?

Not if we camp just outside it. We can then sing songs and toast marshmallows !
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Offline neilep

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« Reply #10 on: 14/03/2009 12:56:15 »
Quote
...otherwise known as "ridiculously stupidly big"

 [:D]

Is that blackhole bigger than J-Lo's bottom?

Those scientists got it wrong. Thye forgot to consider the enormity of J-Lo's exit area !..tch tch tch !!
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Offline yor_on

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« Reply #11 on: 14/03/2009 13:09:59 »
How come we on one side say that there never will be any mass reaching past the event horizon and on the other treat black holes as growing? Where will all that extraneous mass be if so? Growing and propagating for ever towards a event horizon, that as they  also are spinning, creating an enormous frame dragging effect. So what happens if so? You can't assume that this mass building will be 'broken down' in a 'quark gluon soup' as it never reach past the event horizon. And when considering the spin shouldn't this mass outside the event horizon behave somewhat like a stone in a sling, getting 'massed up'? Here is a description of a spinning black hole using the Kerr metric http://www.bun.kyoto-u.ac.jp/~suchii/spinhole.html And here http://www.cosmosmagazine.com/node/873

Read it and ponder.
« Last Edit: 14/03/2009 13:15:19 by yor_on »
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Offline DoctorBeaver

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« Reply #12 on: 14/03/2009 14:08:13 »
How come we on one side say that there never will be any mass reaching past the event horizon and on the other treat black holes as growing? Where will all that extraneous mass be if so?

The mass is inside the event horizon. It can get in, but can't get out again (unless you think Hawking radiation is a real phenomenon). So, there is no dichotomy about "...there never will be any mass reaching past the event horizon" and black holes growing.

In any case, if black holes do indeed contain singularities, then it is just the event horizon that will grow (expand). The singularity would remain a zero-size point.
« Last Edit: 14/03/2009 14:12:30 by DoctorBeaver »
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Offline LeeE

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« Reply #13 on: 15/03/2009 00:30:47 »
Quote
The bigger the black hole, the bigger the gravitational field and the faster it can pull in matter - but that same huge gravitational gradient means that the same matter can release huge amounts of radiation as it falls, blasting other matter further away

Hmm... but once the radiation has 'blasted' other matter further away there will be less in-falling matter, so the amount of radiation will drop, letting the matter be drawn back in towards the BH, which is now even more massive than it was before, thanks to the matter it drew in and which caused the radiation that 'blasted' the matter away.  So if radiation does have a significant effect re 'blasting' away in-falling matter, it seems to me that we should see an oscillation.
...And its claws are as big as cups, and for some reason it's got a tremendous fear of stamps! And Mrs Doyle was telling me it's got magnets on its tail, so if you're made out of metal it can attach itself to you! And instead of a mouth it's got four arses!

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Offline DoctorBeaver

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« Reply #14 on: 15/03/2009 01:02:53 »
It would probably happen over millions of years
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Offline yor_on

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« Reply #15 on: 15/03/2009 10:10:20 »
As I remember it the mass you're observing will from your perspective always be on its way towards that elusive 'event horizon' never ever reaching it. What you are describing I believe to be the 'former' description where we had mass passing the EV, In that scenario all 'mass' will finally reach a center, but in the one I'm referring to, black holes would have to be 'born' at our spacetimes beginning as the mass never will reach the EV. That is as I've understood it






« Last Edit: 15/03/2009 10:14:59 by yor_on »
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Offline DoctorBeaver

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« Reply #16 on: 15/03/2009 10:49:33 »
You're referring to what's known as "The Blue Curtain", where the time dilation is so great to an outside observer that it appears to stand still and matter seems to accumulate at the event horizon. Light accumulating in this way is infinitely blue-shifted (infinities again grrrrrr).

I'm not sure of the current thinking about this.

That's made me wonder about something else. If the time dilation is that great, would we actually be able to observe the innermost part of the acccretion disk rotating? Wouldn't that, too, appear to stand still?
« Last Edit: 15/03/2009 10:51:55 by DoctorBeaver »
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Offline yor_on

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« Reply #17 on: 15/03/2009 12:51:14 »
It is a very strange thing, a black hole. That's a very interesting question DB, I think we will see it moving, as well as observing the 'frame dragging'. and the way I think of it is like this. If we think of that 'accretion ring' and bends it out. Then we use it as a description of a journey taken by me from Earth to a star and back near 'c'. You stay on Earth watching me at all times with that new super telescope, will you be able to follow my travel at all time? Yes you will. Will there be a 'time dilation' seen? Yes there will be. Did that ship at any point seem to stop moving? No it didn't. If it would have been seen to have stopped, what would the consequences have been for our spacetime. But then again, one can easily lose ones way looking at the possibilities inherent in different scenarios :) So I won't swear to anything, I think :)

Here is another persons headache.. http://alrenous.blogspot.com/search?updated-min=2009-01-01T00%3A00%3A00-05%3A00&updated-max=2010-01-01T00%3A00%3A00-05%3A00&max-results=14
« Last Edit: 15/03/2009 14:35:07 by yor_on »
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« Reply #18 on: 15/03/2009 13:12:31 »
I think I'll have to read that a couple more times to understand it fully.
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Offline Vern

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« Reply #19 on: 15/03/2009 13:27:38 »
That's a very interesting link yor_on; you are very resourceful. I've quoted below an interesting observation from the link. It reflects on a notion that I have long held. That notion is; electrons cannot possibly be point particles; indeed point particles can not exist.

Quote from: yor_on's link
Similarly, if electrons and other fundamental particles were actually point particles, they would be behind their own Schwarzchild radii and instead of atoms we'd just have a very large black hole. The amount of an electron's charge and mass that is inside a zero-size volume is zero, which is why QCD gets nonsense when it assumes it isn't.

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Offline yor_on

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« Reply #20 on: 15/03/2009 15:47:00 »
Yep, it was :) but I take it with a amount of salt, I think.
If you think of a photon, then that is said to be both sizeless as well as massless. That would make for a very strange black hole :)

Here is some other strange ideas. Relating to black holes.

'Ancient Galactic Magnetic Fields Stronger than Expected.'
http://www.spaceref.com/news/viewpr.html?pid=26166

how black holes acquire mass.
http://solarsystem.nasa.gov/scitech/display.cfm?ST_ID=265

Black hole spins at the limit.
http://www.cosmosmagazine.com/node/873

Astronomer Discovers Upper Mass Limit for Black Holes.
http://www.physorg.com/news139839433.html


---Optical Black Holes-

Can we create black holes here on Earth?
http://www.eurekalert.org/pub_releases/2000-03/NS-Cwcb-1403100.php

Black hole event horizon created in the lab.
http://www.newscientist.com/article/mg19726434.800-black-hole-event-horizon-created-in-the-lab.html
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Offline Vern

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« Reply #21 on: 15/03/2009 16:55:01 »
Quote from: yor_on
If you think of a photon, then that is said to be both sizeless as well as massless. That would make for a very strange black hole :)
My speculative view of a photon eliminates the strangeness [:)] My photons exist as two plane waves, one electric, and one magnetic, radiating out from central points of maximum electric and magnetic amplitude.

Those were more interesting links yor_on. I suspect though, that artificial black holes can't possibly exhibit the true characteristics of the real critter. They may provide some interesting analogies. That spinning BEC that Hau is working with is fascinating.

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Offline DoctorBeaver

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« Reply #22 on: 15/03/2009 17:00:25 »
yor-on - Some ineresting links there. I'll read through them thoroughly sometime.
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Offline LeeE

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« Reply #23 on: 16/03/2009 13:35:19 »
One of the things to remember when thinking about time-dilation effects near and at the event horizon is that the time-dilation will have consequences on any energy related stuff that occurs there.  So, for example, if you release a probe towards an event horizon and the probes flashes a light back to you at a regular interval, the period between the flashes will get longer and longer as the probes gets closer to the event horizon and the degree of time-dilation increases.  At the same time though, the light itself will get progressively red-shifted and dimmer and dimmer, so while it may seem to be slowing down what you'll see will also be getting fainter and fainter, and eventually be too faint to detect.
...And its claws are as big as cups, and for some reason it's got a tremendous fear of stamps! And Mrs Doyle was telling me it's got magnets on its tail, so if you're made out of metal it can attach itself to you! And instead of a mouth it's got four arses!

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Offline Vern

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« Reply #24 on: 16/03/2009 14:11:12 »
Still the question remains; how can a black hole gain mass if nothing can get past the event horizon?

I still suspect there is something not yet discovered that prevents anything from reaching the singularity. It will always be approaching it; never reaching it; like repeated instances of getting half way there.

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Offline LeeE

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« Reply #25 on: 16/03/2009 14:30:34 »
Still the question remains; how can a black hole gain mass if nothing can get past the event horizon?

I still suspect there is something not yet discovered that prevents anything from reaching the singularity. It will always be approaching it; never reaching it; like repeated instances of getting half way there.

Actually, I'm very much inclined to agree with you.  The laws of Physics, as we currently understand them, just don't work beyond the event horizon because gravitational time-dilation means that the rate of time drops to zero at the event horizon, and you can't do physics without time.

The best answer I can come up with is that both space and time get 'stacked-up' and compressed around the event horizon, at a logarithmic rate, effectively allowing room for an infinite amount of space and time at the event horizon itself.  To a distant observer though, this all appears to occupy a finite volume of space, so although nothing can ever actually cross the event horizon and fall in to the singularity, the total amount of mass in the observed finite volume of space will have increased.
...And its claws are as big as cups, and for some reason it's got a tremendous fear of stamps! And Mrs Doyle was telling me it's got magnets on its tail, so if you're made out of metal it can attach itself to you! And instead of a mouth it's got four arses!

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Offline DoctorBeaver

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« Reply #26 on: 16/03/2009 14:36:25 »
There are those infinities again!

Remember, time dilation does not affect the object falling into the black hole. In its own frame of reference it will still fall in at the rate expected. It is only to an outside observer that it will appear to fall slower & slower. That means that in the frame of reference of the falling object, the blackhole does gain mass.

I can't think past that stage at the moment  [???] but I'm sure it must have some relevance on the issue at hand. What's tickling my brain about it is the way time & space swap places inside, or at, the event horizon. Let me try to think it through & I'll see if I can come up with any of my normal nonsense.
« Last Edit: 16/03/2009 14:44:39 by DoctorBeaver »
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Offline LeeE

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« Reply #27 on: 16/03/2009 14:58:28 »
There are those infinities again!

Remember, time dilation does not affect the object falling into the black hole. In its own frame of reference it will still fall in at the rate expected. It is only to an outside observer that it will appear to fall slower & slower. That means that in the frame of reference of the falling object, the blackhole does gain mass.

Yes, darn those infinities - I don't like 'em either, but I think you've got that a bit back-to-front.  To the observer, the object falling towards the black hole won't appear to move slower and slower, but accelerate, just as things appear to do when we drop something here on Earth.  Nothing that occurs outside of the event horizon is any different to what happens with non-black hole sized gravity wells; it's just a matter of degree.

If the observer is watching something time-based happen on the falling object though, it will appear as though that thing will be happening more slowly.  However, to the object itself, in it's local frame of reference, time will seem to be passing at the normal rate and it's everything else that seems to be changed.

The most important thing to remember is that the conditions for the observer do not change throughout this, but they do for the falling object.
...And its claws are as big as cups, and for some reason it's got a tremendous fear of stamps! And Mrs Doyle was telling me it's got magnets on its tail, so if you're made out of metal it can attach itself to you! And instead of a mouth it's got four arses!

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Offline DoctorBeaver

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« Reply #28 on: 16/03/2009 15:44:46 »
Quote
If the observer is watching something time-based happen on the falling object though, it will appear as though that thing will be happening more slowly.  However, to the object itself, in it's local frame of reference, time will seem to be passing at the normal rate and it's everything else that seems to be changed.

That's what I meant. Maybe I phrased it badly.
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Offline yor_on

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« Reply #29 on: 17/03/2009 20:09:31 »
" A Lenticular Galaxy Reveals Spinning Black Holes "

And "The X-ray glow of those iron atoms is so intense that gravitational heating alone cannot explain it. What that unassuming little graph may represent is the detection of a new source of cosmic energy, one predicted a quarter century ago but never before observed"
Cool heh :)

http://discovermagazine.com/2008/whole-universe/09-a-lenticular-galaxy-reveals-spinning-black-holes
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Offline Vern

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« Reply #30 on: 17/03/2009 20:36:23 »
Very interesting link yor_on; spinning black holes; I'm guessing that we will find that all black holes are spinning. If they are born of stars that are spinning, the angular momentum must be conserved. So the black hole would be a disk.

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Offline dlorde

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« Reply #31 on: 17/03/2009 23:22:19 »
You're referring to what's known as "The Blue Curtain", where the time dilation is so great to an outside observer that it appears to stand still and matter seems to accumulate at the event horizon. Light accumulating in this way is infinitely blue-shifted (infinities again grrrrrr).
That's puzzling - when an object falls into a black hole, it's falling into an increasingly deep gravity well, effectively accelerating away from external observers - light escaping from the edge of the event-horizon should therefore surely be increasingly red-shifted. The photons emitted have the same energy, but it's spread out - stretched in space-time, so should become fainter and redder. By the time apparent movement stops, shouldn't the light be infinitely red-shifted as it takes infinitely long to climb out of the gravity well (although still at C) ??

Please resolve my conundrum.

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Offline Vern

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« Reply #32 on: 17/03/2009 23:52:37 »
You may have an unresolvable conundrum. But you may have spotted a good measure of a black hole. It seems true that if we observe a black hole we should see red-shifted matter radiating back to us as it plummets inward toward the black hole. That should be a signature of a black hole.

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Offline dlorde

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« Reply #33 on: 18/03/2009 00:16:59 »
Well whether the conundrum is unresolvable or not, surely someone can explain why the light is said to be blue-shifted, as if it somehow gains energy emerging from the gravity well, or as if the object falling in is accelerating towards us [???]

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Offline DoctorBeaver

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« Reply #34 on: 18/03/2009 00:22:38 »
It's not emerging, it's heading in. I'm not sure of the mechanics behind it, I just read about it. If I recall correctly it's more to do with time dilation.
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Offline neilep

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« Reply #35 on: 18/03/2009 02:52:25 »
Does this mean that Disney's Black Hole is not authoritative ?
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Offline Vern

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« Reply #36 on: 18/03/2009 04:13:35 »
Disney's black hole is good theatre. I suspect it represents very little similarity with reality. We are still guessing when it comes to the true nature of black holes.

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Offline LeeE

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« Reply #37 on: 18/03/2009 08:11:53 »
Does this mean that Disney's Black Hole is not authoritative ?

Well, old Walt was always more of a biologist than a physicist.
...And its claws are as big as cups, and for some reason it's got a tremendous fear of stamps! And Mrs Doyle was telling me it's got magnets on its tail, so if you're made out of metal it can attach itself to you! And instead of a mouth it's got four arses!

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Offline DoctorBeaver

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« Reply #38 on: 18/03/2009 10:23:39 »
Does this mean that Disney's Black Hole is not authoritative ?

Well, old Walt was always more of a biologist than a physicist.

But look what he did to Bambi's mum. Killed her, he did. Killed her stone dead! Poor Bambi.
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Offline dlorde

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« Reply #39 on: 18/03/2009 12:10:06 »
It's not emerging, it's heading in. I'm not sure of the mechanics behind it, I just read about it. If I recall correctly it's more to do with time dilation.
The object is heading in, sure - but the light it emits must be heading out, otherwise we wouldn't see it. ISTM the time dilation that makes the inward fall and the timeframe of the object appear to slow, will surely increase the wavelength of the light it emits - and the same number of photons over a longer period at longer wavelengths will make it correspondingly dimmer...? [I'm considering this independently of the radiation emitted by the frictional heating by tidal forces of infalling matter from the accretion disk]

DoctorBeaver do you remember where you read about this? My curiosity is aroused now - I'm going to have to find out :-)
 

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Offline dlorde

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« Reply #40 on: 18/03/2009 12:18:37 »
Aha, found it - on Wikipedia (Falling Into A Black Hole):
Quote
...From the viewpoint of a distant observer, an object falling into a black hole appears to slow down, approaching but never quite reaching the event horizon: and it appears to become redder and dimmer, because of the extreme gravitational red shift caused by the gravity of the black hole. Eventually, the falling object becomes so dim that it can no longer be seen, at a point just before it reaches the event horizon. All of this is a consequence of time dilation: the object's movement is one of the processes that appear to run slower and slower, and the time dilation effect is more significant than the acceleration due to gravity; the frequency of light from the object appears to decrease, making it look redder, because the light appears to complete fewer cycles per "tick" of the observer's clock; lower-frequency light has less energy and therefore appears dimmer, as well as redder.


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Offline DoctorBeaver

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« Reply #41 on: 18/03/2009 21:48:02 »
I read it in a book by John Gribben, the author of many science books. I borrowed it from a library about 4 years ago.

Looking through his list of books I found "Unveiling the Edge of Time: Black Holes, White Holes, Worm Holes ". It could have been that 1.
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Offline yor_on

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« Reply #42 on: 19/03/2009 00:59:02 »
DB, here is the link to that those 'new' BH I was referring too. As I read it over a year ago and also found that it then was quite supported by a lot of physicists, it made me wonder where it had gone. http://www.physorg.com/news101560368.html "what is controversial about the new finding is that "from an external viewer's point it takes an infinite amount of time to form an event horizon and that the clock for the objects falling into the black hole appears to slow down to zero," said Krauss, director of Case's Center for Education and Research in Cosmology."
« Last Edit: 19/03/2009 01:01:05 by yor_on »
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Offline dlorde

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« Reply #43 on: 19/03/2009 00:59:41 »
I read it in a book by John Gribben, the author of many science books. I borrowed it from a library about 4 years ago.
Oh yes, Gribben - I've got some of his - 'In Search Of Schroedinger's Cat', 'Schroedinger's Kittens', 'the Matter Myth'. He's usually pretty good.

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Offline yor_on

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« Reply #44 on: 19/03/2009 11:08:49 »
The evidence for Black Holes seems rather overwhelming :)
But when it comes to those spinning at almost 'c' I can't help wondering over how this framedragging expresses itself. First you have the sheer mass in itself, in a non rotating black hole (Schwarzschild geometry) you will have a point of no return at the EV. And with a spinning BH (Kerr metric)it seems to me that this 'point of no return' should be seen even further out, before reaching any EV (event horizon)? Shouldn't this move the EV? And also 'collect' the matter falling in into a concentrated 'density' dragging it around that BH as all matter has an 'inertia'?
« Last Edit: 19/03/2009 11:12:56 by yor_on »
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Offline DoctorBeaver

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« Reply #45 on: 19/03/2009 11:16:36 »
I think I've remembered what that Blue Curtain thing is all about. It's from the perspective of an observer falling into the EH. Does that sound better?
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Offline yor_on

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« Reply #46 on: 19/03/2009 11:50:31 »
If we have light emitted from a object falling into a spinning BH, that light will have to make its way back up the 'gravity well' to the observer, will it then do that 'both' ways, as seen thinking of that spin? I mean, being reflected going against that spin will give it a extreme redshift, but when reflected as light when 'spinning' towards you shouldn't it get a blueshift and because of that have a 'easier' way out from that BH, still being redshifted due to the gravity well but not as much as the light reflected seen from that other angle? But then again it will only have one way to go and that is searching the easiest path out, which will be a spiral, ah, forget it, the light can only go one way :)
And 'red blue shift' will be 'equalized' as it moves around I suppose?
Or, will it? Depending on where its finally comes from meeting your observer??
« Last Edit: 19/03/2009 11:54:10 by yor_on »
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Offline yor_on

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Offline Vern

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« Reply #48 on: 19/03/2009 16:20:01 »
Quote from: yor_on
And 'red blue shift' will be 'equalized' as it moves around I suppose?
Or, will it? Depending on where its finally comes from meeting your observer??
It seems that a spinning black hole should appear as both red shifted and blue shifted depending upon the circumference observed. My guess is a galactic black hole would be spinning in the plane of galaxy in the centre of a huge accretion disk. I doubt that black holes exist as a singularity for the same reasons cited in yor_on's link. You can never get completely there because of the relativistic behaviour of light and matter.

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Offline LeeE

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« Reply #49 on: 19/03/2009 18:18:29 »
I think I've remembered what that Blue Curtain thing is all about. It's from the perspective of an observer falling into the EH. Does that sound better?

That sounds reasonable.
...And its claws are as big as cups, and for some reason it's got a tremendous fear of stamps! And Mrs Doyle was telling me it's got magnets on its tail, so if you're made out of metal it can attach itself to you! And instead of a mouth it's got four arses!