Scientists watch black hole feast on unlucky star

May 02, 2012 by Mariette le Roux

Scientists have witnessed the rare spectacle of a supermassive black hole devouring a star that had ventured too close -- an event that occurs about once in 10,000 years, they reported on Wednesday.

Matter-sucking black holes normally lurk dormant and undetected at the centre of galaxies, but can occasionally be tracked by the scraps left over from their stellar fests.

"Black holes, like sharks, suffer from a popular misconception that they are perpetual killing machines," said researcher Ryan Chornock from the Harvard-Smithsonian Center for Astrophysics in Massachusetts.

"Actually, they're quiet for most of their lives. Occasionally a star wanders too close, and that's when a feeding frenzy begins."

If a star passes too close, the black hole's can rip it apart before sucking in its gases, which are heated by the friction and start to glow -- giving away the silent killer's hiding place.

Chornock and his colleagues observed such a glow in May 2010 through a telescope mounted on Mount Haleakala in Hawaii, as well as a NASA satellite.

The flare brightened to a peak that July, before fading away over the course of a year, the scientists said.

"Initially we didn't know exactly what this flare was because it was so bright that when we looked at the galaxy we couldn't see the stars to determine how far away the galaxy was," study co-leader Suvi Gezari of John Hopkins University in Baltimore, Maryland, told AFP.

Observations over several months allowed the team to conclude that the black hole was at the centre of a galaxy 2.7 billion light-years away, and about three million times the mass of our Sun -- similar in size to the Milky Way's central black hole.

Its victim was probably a star in its late, red giant phase which had tempted fate by wandering to within a third of an astronomical unit (150 million kilometres/ 90 million miles) of the black hole -- about the distance of Earth from the Sun.

"This is the first time where we actually have enough detailed information that we can actually determine what kind of star was torn apart by a black hole and how big the black hole was that did it," said Gezari.

She said this was the first such space feast observed from beginning to end, and "that is very exciting because that time scale is how we determine how big the black hole is".

The scientists concluded that the eaten star had lost its hydrogen outer shell in a previous pass by the black hole, leaving just its helium core to be consumed in round two.

"It was really spectacular to have so much info and have all the pieces of evidence come together to form a consistent picture of what happened," said Gezari.

are very dense regions in spacetime with a gravitational force so strong that even light cannot escape. Scientists who study them hope to learn more about the evolution of galaxies.

Stars in our own Milky Way galaxy, including the Sun, are too far away to be at risk of being consumed, said Gezari.

"We would have to wait at least 10,000 years before we would be able to see a star being gobbled by our own black hole," she said.

"So the best way to find these events is not to wait around for our own Milky Way galaxy to gobble a star, we actually have to look at hundreds of thousands of galaxies in the sky to catch one in the act of shredding up a star."

Explore further: Image: Chandra's view of the Tycho Supernova remnant

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evropej
2.1 / 5 (7) May 02, 2012
Images?
CHollman82
3.2 / 5 (9) May 02, 2012
Its victim was probably a star in its late, red giant phase which had tempted fate by wandering to within a third of an astronomical unit (150 million kilometres/ 90 million miles) of the black hole -- about the distance of Earth from the Sun."


About? An AU is defined to be the average distance from the Earth to the sun.

Images?


Probably not in the visible spectrum... they could share tables of data with you I suppose...
Lurker2358
1.7 / 5 (6) May 02, 2012
Probably not in the visible spectrum... they could share tables of data with you I suppose...


I assume most of it would be gamma and x-ray.

The gravitational potential energy from an "elevation" just outside the event horizon of such a massive black hole vs the event horizon itself is an obscenely huge value: far more energy than the star produced in it's entire life time through fusion.

I figure roughly half the radiation is direct straight back into the black hole, so what you see in a telescope is only a tiny fraction of HALF the energy produced, which happens to be pointed in your direction...and apparently it was brighter than all the stars in the galaxy combined. Incredible.
hyongx
5 / 5 (2) May 02, 2012
I think it is totally remarkable that the consumption of the star takes less than a year. Normally I think of astronomical events as occuring over huge time scales.
Also cool is that this event actually occurred 2.7 billion years ago. Talk about time-lapse photography.
Lurker2358
1 / 5 (7) May 02, 2012
At 3 million solar masses, the tidal forces from this black hole would be enough to spaghettifi planetary masses even at a distance of roughly 100A.U.

A star has a lot more gravity, so it would survive for much longer, but pretty much anything passing within 100a.u. is screwed, eventually, even though the event horizon itself is so much smaller than that.
CHollman82
1 / 5 (3) May 02, 2012
Yes, well, the EH is the distance at which light cannot escape, obviously that distance is much much greater for dense matter.
casualjoe
not rated yet May 02, 2012
I think it is totally remarkable that the consumption of the star takes less than a year.


I also thought this, but because I thought time ran slower in a gravitational well, so viewing from Earth all the matter that a black hole consumes, we would see its velocity decrease to a stop, radiating for a time on the cosmic scale.
I suppose for us, a year is a long time to observe a star falling in whilst approaching the speed of light (from the stars frame of reference).

Absolutely fascinating!
yyz
5 / 5 (3) May 02, 2012
Terriva
1.7 / 5 (6) May 02, 2012
It could be just a supernova - or not? How the astronomers recognized, it's accretion of star with black hole?
Vendicar_Decarian
4.2 / 5 (5) May 02, 2012
If black holes actually exist, the event is ongoing and will continue to be ongoing for the rest of eternity. At least from our perspective.

"I think it is totally remarkable that the consumption of the star takes less than a year." - Hyong
bluehigh
1.2 / 5 (10) May 02, 2012
Here is a really good close up photo from NASA.

http://www.smh.co...00x.html

Lurker2358
1 / 5 (8) May 02, 2012
If black holes actually exist, the event is ongoing and will continue to be ongoing for the rest of eternity. At least from our perspective.


You're backwards.

Check the gravitational time dilation formula.

From the point of view of an observer in the Star's reference frame, the event lasts extremely long. The star could have lived out it's entire lifetime just outside the event horizon.

The time dilation could have been a billion or even ten-billion to one.

From our point of view, the event is nearly instantaneous, relatively speaking.
casualjoe
2 / 5 (2) May 02, 2012
http://www.smh.co...00x.html

That's a computer simulated image, however it is beautiful, the way it shows the gravitational waves of the star as it's smeared across space and time towards that huge black hole.
http://hubblesite...image/a/
yyz
4.3 / 5 (6) May 02, 2012
"It could be just a supernova - or not?"

A supernova seems unlikely, as the event was observed, in visible light, for over a year. No known supernova outside the Local Group, much less at the distance estimated, has ever been continuously visible for such a great length of time. The study's authors also point out that the host galaxy seems to lack a population of massive, young stars conducive to supernova formation.

Spectroscopic analysis of the event also rules out any flaring behaviour in the nucleus of the host galaxy(AGN activity). A paper describing the multiwavelength observations of this unusual event can be found here: http://hubblesite.../pdf.pdf
bluehigh
1.3 / 5 (16) May 02, 2012
This is clearly labelled a photo.
http://www.smh.co...00x.html

If its an artists impression (computer assisted or not) then the veracity of the entire article would be in doubt. The media would never deceive us into believing bad science. Would they?
Black Holes. Gravitational waves. Hockey sticks. Bad science.

yyz
4.7 / 5 (13) May 02, 2012
@bluehigh,

Why not seek out a better source for such info than the Sydney Morning Herald, like here, for instance: http://hubblesite...image/a/

While you're there, check out the accompanying movie, it's pretty cool too: http://hubblesite...video/a/
bluehigh
1.7 / 5 (19) May 02, 2012
If I did not have a background in science, how would I now know what to believe. Is this article just a fantasy narrative. Is the photo in a major metropolitan newspaper a fraud. Yes. Clearly, no evidence of a black hole doing anything, just a guess backed up by a concocted streak of colored crayon or a Hubble image of a flash of light passed off as representing fact.

Nothing cool about the video, its a fraud, a fake cartoon that deceives and bad science.
casualjoe
4.6 / 5 (10) May 02, 2012
You can't blame hubblesite for the sydney morning heralds lack of detail, they're writers are clearly not trained in cosmology.

Just look on the official websites for the proper scientific articles, no big deal.

Here's one www.cfa.harvard.
Code_Warrior
5 / 5 (6) May 02, 2012
@lurker
No, Vendi has it partly right. Observers never actually see anything fall into a black hole because they perceive time slowing down in the reference frame of the unfortunate victim. The reference frame of the victim sees no difference in their own time frame and will observe themselves crossing the event horizon as if nothing changed (outside of the uncomfortable gravity), but the victim perceives the observer's time frame as being sped up.

It is this contradictory view of events that led Leonard Susskind to develop the Holographic Principle that explains that the observer sees the victim getting spread out in 2D on the event horizon as opposed to just moving slower and slower. Susskind used this idea to demonstrate that information is not lost as Hawking stated, but is retained as a 2D hologram on the event horizon that connects the Information formerly lost via Hawking radiation to the destruction of matter at the singularity.
bluehigh
1.5 / 5 (15) May 02, 2012
Take a closer a look? At what? A bright flash and a cartoon. No evidence that its a star being sucked into a black hole. I say again this is bad science and exactly the kind of article both here, in the lamestream media and on source (official) sites, that brings science into disrepute. How can anyone support such weak evidence? Oh well ... gotta go tend the pineapples, I'll feel better then!
Lurker2358
1 / 5 (9) May 02, 2012
Code_Warrior:

The matter does not even need to "cross" the event horizon.

As it falls deeper and deeper into the gravity well, it's own density increases until it eventually achieves critical mass in it's own right, which causes the event horizon to grow.

You can see that intuitively by imagining an event horizon, and then place an infinitesmal layer of matter over the surface of the horizon. As seen from the outside, the event horizon grows to contain the new layer of matter.

A black hole's event horizon actually grows faster than what is predicted by the Schwartzchild radius for any given mass value, because when new mass merges with the black hole; the new event horizon is always larger than what would be created by a single mass equal to the sum of the parts.
Vendicar_Decarian
5 / 5 (3) May 02, 2012
It isn't 2d of course since there is an ever decreasing volumetric shell that to an outside observer, contains the in-falling matter - or out-falling matter in the case of the universe itself.

"It is this contradictory view of events that led Leonard Susskind to develop the Holographic Principle that explains that the observer sees the victim getting spread out in 2D on the event horizon as opposed to just moving slower and slower." - Code
Pyle
5 / 5 (4) May 03, 2012
VD: I think Code got the theory correct. QC's comment that the fall into the EH is instantaneous to the observer was backwards. Susskind's Holographic Principle demonstrates the complete opposite of what QC said. I personally believe that our theories are only approximations and the singularities that present themselves in GR merely represent the broken limits of our theories' predictive capabilities.

Rather than a gravity dominated situation suggested by a black hole, I suspect that something else counteracts gravity at such extreme scales to prevent the true singularity that presents itself in the math. Something along the lines of Moffat's fifth force in MOG would do the trick, but a gut feeling is as far as I can take it.

bh: It is a photo of a computer simulation. Get over it. If you don't like the extrapolations made by scientists go bury your head in the sand. If our measurements of this event match the simulation's outputs, Yay!, else, let's draw up new equations.
CardacianNeverid
3.7 / 5 (9) May 03, 2012
Take a closer a look? At what? A bright flash and a cartoon. No evidence that its a star being sucked into a black hole. I say again this is bad science and exactly the kind of article both here, in the lamestream media -BlueTard

Poor Blue Tard. Knows nothing. Trusts no one. Remains ignorant. Poor Blue Tard.
CardacianNeverid
4.3 / 5 (6) May 03, 2012
Rather than a gravity dominated situation suggested by a black hole, I suspect that something else counteracts gravity at such extreme scales to prevent the true singularity that presents itself in the math -Pyle

Hypothesis: As you approach ever smaller scales towards the (mathematically) infinitesimal singularity, I would guess that quantum effects would come into play such as the uncertainty principle which may 'smear out' the singularity.
Vendicar_Decarian
3.7 / 5 (6) May 03, 2012
Down boy.. Down.

"Poor Blue Tard. Knows nothing." - CardacianNeverid
bluehigh
1.5 / 5 (8) May 03, 2012
Well, between Vendi and Code they nailed it. A Black Hole sucking up a Star event would not be observable in any case. As for C.Neverid you manipulative bastard, just want spoil my breakfast rant. Publish the science and not the bullshit.

CardacianNeverid
4.4 / 5 (7) May 03, 2012
As for C.Neverid you manipulative bastard, just want spoil my breakfast rant -BlueTard

You're welcome.

Publish the science and not the bullshit -BlueTard

To what end? You are impervious to scientific publications and findings, as you have already demonstrated here and elsewhere. Get back to your fruit-loops tard.
bluehigh
1.6 / 5 (7) May 03, 2012
Oi! Ya drongo. Fair dinkum mate its blue tard or pineapple tard. Now, for your delectation ... to sum up the lamestream general dumb down we get this pop-science tripe.

http://news.ninem...cky-star

Its got it all from todays blackhole news. The video, the pics all the bullshit. Do you feel pleased with Pop Science fantasy?

bluehigh
1.5 / 5 (8) May 03, 2012
To what end?


You are kidding, right? Theres almost nothing scientific about this article at all. Its a beat up bunch of pop science to try engage the general public that fails miserably when found to be a misrepresentation. Its a disgrace, bad science and bad for science in the long run.

CardacianNeverid
4.3 / 5 (6) May 03, 2012
You are kidding, right? Theres almost nothing scientific about this article at all. Its a beat up -BlueTard

What's the beat up tard boy? You don't think black holes are real? Or that the event described happens rarely for us to observe?
bluehigh
1.5 / 5 (8) May 03, 2012
I can only believe that black holes are real and NASA has photos with a video to prove that black holes can suck in stars. I don't need to think .. baa baa.

MarkyMark
4 / 5 (4) May 03, 2012
I can only believe that black holes are real and NASA has photos with a video to prove that black holes can suck in stars. I don't need to think .. baa baa.



Perhaps its best you go back to whatever fabtasy you believe in Bluehigh! It seems you are too high to do more than troll.

Toodles!!!
HannesAlfven
1.6 / 5 (7) May 03, 2012
@bluehigh is dead on. Science was meant to differ from religion insofar as everybody is encouraged to decide for themselves, based upon the evidence, what to believe. But, increasingly, we see the public trying to align themselves with sources instead of arguments. To some extent, it shouldn't surprise us, for the science textbooks have left out nearly ALL of the controversies of science which led to this point. And wikipedia's policies elevate the status quo in science to some sort of special case.

The scientific method breaks down at the point where people decide to not seek out criticisms, for its those criticisms which lead to ideational fluency. Creative problem-solving does not occur in the absence of a familiarity with lots of ideas/solutions. To the extent that the *public* fails to seek out alternatives, those alternatives will be that much harder of a sell, regardless of the evidence which support them.
Pyle
3.7 / 5 (3) May 03, 2012
@EUadvocate:
Yup. We definitely have entered a different age of scientific discovery. In the past marginalized research could go out and find a home more easily than in the current broadly interconnected world. The inertia of the "standard" models and whatnot has the potential to shut out legitimate alternatives. The opportunities for groupthink abound.
However, I think there is an argument that the more information sharing there is the less waste there will be as well. The resources we use can be funneled to the most promising of the alternatives; preventing waste on ideas that have already been disproved.

I think the Electric Universe is a great example. Lots of the ideas in EU theory have potential. There is a lot of things we still need to learn about plasma and interstellar space. However, the preponderance of EU enthusiasts are hucksters spinning tripe, promoting a cult. Focusing of effort on EU theory deserves the critical skepticism it receives.
Code_Warrior
5 / 5 (2) May 03, 2012
Well, between Vendi and Code they nailed it. A Black Hole sucking up a Star event would not be observable in any case.

What we cannot observe from the outside is the matter actually disappearing behind the event horizon. However, we can hypothesize that an accretion disk will form around a black hole that will get extremely hot and may be visible as it radiates away its heat energy. We can measure the exact EM spectrum of the flash, determine the approximate amount of energy released, and use that info to rule out well known phenomena. If we then compare the flash spectrum and energy data to the energy signature we would expect from the hypothesized black hole accretion disk and find a close fit we can at least state that close fit as the best explanation we have. While we can't say with 100% certainty that the best fit explanation is correct, we can say that the evidence supports the hypothesis. Removing all these disclaimers to improve article readability is OK with me.
A2G
1 / 5 (6) May 05, 2012
IF there are black holes then why do not stars or even just one star disappear or at least dim as they go behind one and then reappear later when they move out from behind one?

Black holes are a patch made up to cover the lack real understanding of what holds it all together. Then you add in dark matter to cover the hole in the patch, and then smother on a helping of dark energy and you have to total mess that still doesn't explain it all.

But neither does the EU model. There are still things to be discovered. Just like at CERN. You research until you find the answer that truly fits and can be tested over and over. Not just here and there.
Shelgeyr
1 / 5 (5) May 05, 2012
Chornock and his colleagues observed such a glow in May 2010 through a telescope mounted on Mount Haleakala in Hawaii, as well as a NASA satellite.


If you removed the word "such" from this quote, then you'd have the only factual statement in this article, not counting the quotes (I'm assuming that the persons being quoted actually did say what is recounted). The rest of this entire article is bald supposition and does not warrant its portrayal as scientific discovery.

They observed a glow. That's what happened. The rest is pure, weapons-grade fiction.
Lurker2358
1 / 5 (2) May 05, 2012
A2G:

Black holes aren't a patch to anything.

They've been hypothesized for several centuries, actually.

the modern concept arose after Einsteins speed of light postulate and relativity, as a natural mathematical limit problem.
holtonsys
not rated yet May 06, 2012
Hawking's theoretical black hole is demonstrated by the same graphics artists that give us the "Incredibles" and other fantasy tales. Since 80% of the universe is unknown matter or energy, how can it actually be called a science? Just sayin'
antialias_physorg
not rated yet May 07, 2012
"We would have to wait at least 10,000 years before we would be able to see a star being gobbled by our own black hole,"

Not to mention that observation would be rather difficult - the entire disc of the galaxy being in the way and all.

stellar-demolitionist
5 / 5 (1) May 07, 2012
"We would have to wait at least 10,000 years before we would be able to see a star being gobbled by our own black hole,"

Not to mention that observation would be rather difficult - the entire disc of the galaxy being in the way and all.



It's not quite so bad. The stars orbiting Sag A* can been clearly seen in the near IR. If there was a star headed directly for it, ongoing monitoring would detect it. (Sag A* is the radio source identified as the accretion around the central Galactic black hole.)
antialias_physorg
3 / 5 (2) May 07, 2012
As mass falls into the black hole you can expect all kinds of weird things happening. We're talking energies here that are far greater than any collider could summon up on Earth.
It seems unlikely that any kind of massive particle could reach the singularity intact. Even such minute differences as quark 'positions' in nucleons (neutrons, protons) would be enough to rip it apart by tidal forces. Electrons are iffy since they don't seem to be subdivisible.

So one hypothesis is that you could only have photons at the singularity (i.e. a superposition of fields) but that would violate charge conservation

Then again one could have space stretch out faster inside at some point than stuff could fall in (i.e. faster than c). So stuff could fall in indefinitely and never reach the singularity.

Angular momentum is another problem. A singularity doesn't have any (radius equals zero). But angular momentum should be conserved (hence the Kerr singularity).

Still much to learn with black holes
antialias_physorg
not rated yet May 07, 2012
It's not quite so bad. The stars orbiting Sag A* can been clearly seen in the near IR.

That's what I meant. It's far easier to observe black holes in other galaxies than our own. We see most other galaxies not directly from the side. But with our own we're more or less fully in the galactic plane (i.e. everything is in the way of observing our black holes directly)
jabailo
1 / 5 (1) May 07, 2012
Maybe the black hole ate all the dark matter.
stellar-demolitionist
not rated yet May 07, 2012
The biggest advantage that other galaxies have is there is a whole lot more of them. This is essentially the point of the author on the "10000 year" statement.
Vendicar_Decarian
5 / 5 (1) May 08, 2012
You will have photo's of the acreation disk in about 10 years.

"I can only believe that black holes are real and NASA has photos" - BlueHigh

Until then you will have to content yourself with this...

http://www.youtub...DH3x56eE

Time index 9 minutes

Others

http://www.youtub...=related

http://www.youtub...kRkexw10

http://www.youtub...e=fvwrel
Vendicar_Decarian
5 / 5 (1) May 08, 2012
"Angular momentum is another problem. A singularity doesn't have any (radius equals zero). But angular momentum should be conserved (hence the Kerr singularity)." - antialias

Current thought is that it is conserved through frame dragging however it is probable that there is no singularity and that Black Holes are extended objects in The form of a shell or in the case of a rotating black hole, a torus.

tasha90
1 / 5 (4) May 09, 2012

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casualjoe
1 / 5 (1) May 09, 2012
Surely, if there was a true singularity at the centre, the universe wouldn't look like it does today. Any density of matter around the accretion disc would be easily overcome by an infinitely strong gravitational force, black holes would just dominate.
There must be some limit to the rate at which black holes can receive matter, which could balance between the mass of the hole and the infalling matter's degeneracy pressure.
Vendicar_Decarian
5 / 5 (1) May 10, 2012
The immediate implication to this is that no stationary outside observer sees matter fall into a black hole and hence to them, all measurements will show that a black hole is actually a shell of highly compacted matter consisting of all of the matter that has ever fallen upon/into it.

The need for a singularity is therefore vanquished.

"Leonard Susskind to develop the Holographic Principle that explains that the observer sees the victim getting spread out in 2D on the event horizon as opposed to just moving slower and slower." - Code
Vendicar_Decarian
5 / 5 (1) May 10, 2012
No. The singularity is at the outer edge.

"Surely, if there was a true singularity at the centre, the universe wouldn't look like it does today." - Casualioe
Vendicar_Decarian
5 / 5 (1) May 10, 2012
What makes you think that this doesn't happen?

"IF there are black holes then why do not stars or even just one star disappear or at least dim as they go behind one and then reappear later when they move out from behind one?" - A2G

It hasn't been observed in part because Black Holes are very small and the probability of alignment with something that can move behind is exceedingly improbable.
Vendicar_Decarian
5 / 5 (2) May 10, 2012
They are the natural consequence of the well tested theory of general relativity.

"Since 80% of the universe is unknown matter or energy, how can it actually be called a science? Just sayin'" - foofie

They are presumed to exist because the theory has been shown to be correct in every instance in which it is tested, to the precision of the experiment employed in the test.

antialias_physorg
4 / 5 (4) May 10, 2012
Any density of matter around the accretion disc would be easily overcome by an infinitely strong gravitational force, black holes would just dominate.

The density is irrelevant. It is only the total mass contained in the singularity that generates the gravitational force.

Consider our sun. If you were to turn the sun into a black hole singularity (which it can't bcause you only get that for stellar objects with greter than 3 solar masses) then the Earth would still orbit that singularity just like it orbits the sun now (because the mass is the same).

Actually, for all points that are further away than the current surface of the sun nothing would change at all (gravity-wise. Of course, they wouldn't be getting any light anymore)

Only when you get (much) closer would things start to diverge (for one solar mass you get a event horizon at around a radius of 3km. For an Earth size mass it would be 9mm)
antialias_physorg
4 / 5 (4) May 10, 2012
IF there are black holes then why do not stars or even just one star disappear or at least dim as they go behind one and then reappear later when they move out from behind one?

1) Because black holes are very, very small. Even such monsterous black holes which contain a billion solar masses merely have a Schwartzschild radius of 20 times the size of the sun.

2) The gravitational force bends light - so even if a star went behind a black hole whose Schwartzschild radius was larger than the star you would see nearly all the light as an Einstein ring (or even multiple Einstein rings).

Observed examples of Einstein rings:
http://en.wikiped...ein_ring
antialias_physorg
4 / 5 (4) May 10, 2012
There must be some limit to the rate at which black holes can receive matter

Black holes are self limiting in a way. They consume stuff that is (very) close - but after that is gone they basically starve for a long time.

The accretion disc is a limiting factor: As it tumbles in it heats up. The radiation pressure is enough to drive gas moleucules further out away fom the black hole. this creates an exclusion zone around the black hole (until the accretion disc is consumed to a point where that radiation pressure lessens)

The eating habits of black holes are best described as on-again, off-again...with the occasional snack from ejected binary companions.
casualjoe
1 / 5 (1) May 10, 2012
So you don't think the actual matter of a black hole is slightly smaller (in volume) than the event horizon of that hole as viewed from earth. Like if the hole had a thin surrounding atmosphere of superluminal downward spiralling matter and energy whilst it consumes something, and then just empty space when it doesn't?
casualjoe
1 / 5 (1) May 10, 2012
Well, matter would reach superluminal speeds yet any radiation emmited directly away from the black hole, from within the event horizon would fall slowly in.
Parameters all dependent on the mass of course.
antialias_physorg
4 / 5 (4) May 10, 2012
The mass is (probably) concentrated at the singularity point or in a toroidal/2D Kerr singularity - depending on how you want to go about preserving angular momentum (the jury is still out on that one and we're ulikely to be able to look inside a black hole in the future to find out for sure).

The matter of a black hole has to be contained in a space smaller than the event horizon, since the event horizon is defined as that distance from the center (as seen from the outside!) where an entity going at the speed of light could not escape. Anything that has mass cannot go at the speed of light.

There is currently no known force that could stop the collapse of the matter inside a black hole, so the collapse will go on indefinitely (although the term 'matter' becomes iffy because the closer you get to the center the stronger the tidal forces become and at some point matter, as we understand it, just won't be able to hold together. Not even single protons/neutrons.)
antialias_physorg
4 / 5 (4) May 10, 2012
Like if the hole had a thin surrounding atmosphere of superluminal downward spiralling matter and energy whilst it consumes something

At no point is there anything superluminal outside (or even inside) a black hole.

yet any radiation emmited directly away from the black hole, from within the event horizon

There is no such direction. You literally cannot point anywhere 'further away' from the singularity once you cross the event horizon. Every direction will only get you closer to the singularity.

If you're at the event horizon there is exactly one direction (directly 'behind' you as you fall in) that will point to a path which stays the same distance from the singularity for a beam of light emitted at that exact moment. An instant later (after you cross over) there isn't even that anymore.

Only radiation that was emitted from an object while still outside the event horizon has any chance of gettin away.
casualjoe
1 / 5 (1) May 10, 2012
Surely, once matter (or boson soup whatever you want to call it) falls beyond the event horizon it falls faster than light relative to us? Because radiation cannot leave, like you said. I was just hypothesising that; in the space just within the event horizon, there will be some radiation that will be moving surprisingly slowly, similar to a mirror image of the accretion disc.
antialias_physorg
4 / 5 (4) May 10, 2012
falls beyond the event horizon it falls faster than light relative to us

Why should it? As long as it has mass it can't go faster than light. Space isn't flat inside the event horizon.
there will be some radiation that will be moving surprisingly slowly

It will always move at the speed of light (if you're talking about photons. The term 'radiation' also refers to particles like electrons/betas, neutrons or helium nuclei). Photons can't do anything BUT move at the speed of light. They're not moving slower. Space is just bent in a way so that they aren't getting anywhere nearer the event horizon.

similar to a mirror image of the accretion disc.

stuuf inside the event horizon is a bit different from stuff outside (for one there is a path from the outside in, but no path from the inside out)
casualjoe
1 / 5 (2) May 10, 2012

Why should it? As long as it has mass it can't go faster than light. Space isn't flat inside the event horizon.

They're not moving slower. Space is just bent in a way so that they aren't getting anywhere nearer the event horizon.

similar to a mirror image of the accretion disc.

stuuf inside the event horizon is a bit different from stuff outside (for one there is a path from the outside in, but no path from the inside out)


The ridiculously curved space beyond the event horizon would cause mass to fall faster than light.
I'm talking about what we should expect to observe if it were possible to see into a black hole from earth, apologies for not making this a bit clearer.

Vendicar_Decarian
5 / 5 (1) May 10, 2012
Not possible since no infalling matter never reaches the event horizon from the vantage point of a stationary observer outside.

No signal can escape that will provide information contradictory to that view.

The only matter that can be contained within the event horizon will be the initial matter that created it, if it can exist inside at all.

"The matter of a black hole has to be contained in a space smaller than the event horizon" - Antialias
Vendicar_Decarian
5 / 5 (1) May 10, 2012
Not possible since there is insufficient energy available to produce such a velocity.

"The ridiculously curved space beyond the event horizon would cause mass to fall faster than light." - casual
antialias_physorg
4 / 5 (4) May 10, 2012
The ridiculously curved space beyond the event horizon would cause mass to fall faster than light.

Nope. Unless you have found a way to overcome Relativity that ain't gonna happen.
I'm talking about what we should expect to observe if it were possible to see into a black hole from earth

Nothing. No matter how deep you could look inside: there is nothing coming your way.
What goes for the event horizon (no way for a photon or anything else to come out) goes doubly for any point or surface inside the event horizon.
casualjoe
1 / 5 (1) May 10, 2012

Nope. Unless you have found a way to overcome Relativity that ain't gonna happen.

It is, by using imagination. It was just a little thought experiment, to theorise why we observe what we do. Although when S2 came really close to sagittarius A* but didn't slow down (viewed from earth) whilst it was so deep into A*'s gravity makes me question my entire thinking!
Vendicar_Decarian
5 / 5 (1) May 11, 2012
"If you're at the event horizon there is exactly one direction (directly 'behind' you as you fall in) that will point to a path which stays the same distance from the singularity for a beam of light emitted at that exact moment. An instant later (after you cross over) there isn't even that anymore. " - Antialias

To clarify...

Once inside, no matter which direction you look (from all directions) you see the singularity. Just as we see the singularity of the BB from all directions.

Coincidence?
antialias_physorg
3 / 5 (2) May 11, 2012
Coincidence?

No connection between the two phenomena because they are based entirely on different mechanisms.

The universe does not have an 'outside' from which stuff falls in.
A black hole does.

The big bang location is everywhere in the universe (you and I are actually standing in the place where the big bang happened. Freaky if you thinnk about it).
The singularity is in one place.
While you fall into a black hole - even when you have passed the event horizon - you're not at the place of the singularity (yet)

Black holes bend the light so that everything points to the singularity.
In the universe every point was the originator of radiation from the BB so you see it comeing from all directions (not because the paths are bent)

Once inside, no matter which direction you look (from all directions) you see the singularity.

No you wouldn't. Even though all paths FROM you point there, there is no path TO you from the singularity.

It's strictly a one way street.
antialias_physorg
3 / 5 (2) May 11, 2012
Point being: If the universe were the inside of a black hole and the Big Bang the singularity we wouldn't be able to see it.

Nope. Unless you have found a way to overcome Relativity that ain't gonna happen.
It is, by using imagination. It was just a little thought experiment, to theorise why we observe what we do.

I'd really urge you to watch this short lecture by Richard Feynman. There you'll see that 'using your imagination' like that (without observable consequences) is unscientific.
It's day-dreams. Nice, but ultimately (in a scientific context) useless. Your approach is solidly in the 10-20-30 category (you'll know after watching the video)
http://www.geek.c...2012059/
Origin
1 / 5 (3) May 11, 2012
way to overcome Relativity that ain't gonna happen
You have no evidence for it. The FLRW metric used in L-CDM model (standard model of the Big Bang cosmology) corresponds exactly the Schwarzchild metric turned inside out. It's apparently general relativity based model, which allows no existence of physical law inside of singularity.
antialias_physorg
3 / 5 (2) May 11, 2012
You have no evidence for it.

I have no evidence for stuff not being faster than light? Is that what you are saying?
That's the same argument that says: There is a god because you have no evidence against it.

As with every other thing in science: if you have an idea then you need to find consequences which can be tested. As far as I know testing inside the event horizon of a black hole is a no-go (at least if you ever hope to get the information gained to someone on the outside).

So you may start (since you madethe claim): if stuff travels faster than light: what are the (testable) consequences? Then we will see.
casualjoe
1 / 5 (1) May 11, 2012
I uploaded a few words from Feynman a while ago, he's definitely a hero of mine.. http://www.youtub...dBGCukmA

if stuff travels faster than light: what are the (testable) consequences?


Proof for the existence of black holes is growing, if they are shown to exist, then there's a strong case for understanding gravity as 'space itself' that is falling faster than light once beyond the event horizon and its accelerates towards the singularity over time, relative to us on Earth.
Origin
1 / 5 (3) May 11, 2012
That's the same argument that says: There is a god because you have no evidence against it.
I don't believe, the universe is inside of black hole. But it's not true, we have no evidence for it.

http://phys.org/n...631.html http://phys.org/n...839.html

Actually, I had rather tough job to explain, why this model is wrong to various proponents of it.