# Could merging black holes be more common than previously expected?

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#### evan_au

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##### Could merging black holes be more common than previously expected?
« on: 02/04/2016 01:22:10 »
Scientists previously expected that an exploding star could form a neutron star (or black hole if the star was more massive). It is thought that supernovas should happen about once every century in a typical galaxy.

It was thought that merging black holes or neutron stars could arise from binary star systems, where the remnants of the two stars slowly approach each other by gradually radiating gravitational energy, which could take billions of years. This would make it a fairly infrequent event.

A recent paper suggested a different mechanism that could form a closely orbiting pair of black holes or neutron stars in a single event: When a spinning star collapses in a supernova, the considerable angular momentum has to go somewhere. It is hard to shed all that angular momentum for the star's mass to collapse into a single neutron star or black hole, right in the center.

Instead, this paper suggests that the collapsing mass of the star accumulates at two (or more?) centers inside the star, forming a closely-orbiting pair of black holes or neutron stars, which now carry most of the star's original angular momentum. Because they are massive objects in close orbit, they will rapidly radiate gravitational energy, and will quickly merge in a tsunami of gravitational energy.

Could this mean that closely orbiting and merging black holes or neutron stars might be far more common than previously estimated?

What do you think?  (I am sure the LIGO team would be happy!)

#### jeffreyH

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##### Re: Could merging black holes be more common than previously expected?
« Reply #1 on: 02/04/2016 10:47:11 »
I think that the universe will surprise us in even more unexpected ways.

#### Tim the Plumber

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##### Re: Could merging black holes be more common than previously expected?
« Reply #2 on: 02/04/2016 10:56:04 »
I think you need to link to the paper but since it will be way over my head don't rush on my account.

Can this happen if the result is a pair or more of Neutron Stars? If so it might explain the lack of space aliens out there. The collision of such objects is supposed to be powerful enough to sterilize entire galaxies.

Humanity could be ultra lucky in yet another way. Even as an atheist I am struck that the odds of us happening are so long that you do have to get to a point of saying that it seems something is at least gardening earth and humanity.

#### JoeBrown

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##### Re: Could merging black holes be more common than previously expected?
« Reply #3 on: 02/04/2016 11:08:57 »
I don't know what I think in this regard.

It's all very fuzzy to me and I'd like to know!

It should be stated it was once thought about once a century, but we've collected evidence on a lot more events in one small window of our time by extending the range of visible evidence we can gather.  I don't know how that affects the century postulation at all.  Too many variations in time windows of observation, to not have effects on what we think we know.

If there's 100 billion galaxies in the visible universe each likely containing at the very least one black hole (super massive or not???)   100/14  seems like more than 1 a century to me.  But that's not much information to know on.

Do we believe that super nova events happen often, at a fairly regular frequency?  13-14 billion years is a long time to take into consideration, leaving a lot of room for speculation on what any standard deviant might mean.   So far we have Dark Energy (DE) postulated curving differently at the beginning and opposite way toward present.  I think I catch the drift.  I think I know what it means.  I'd like to explain it to others.  But how!  I've heard we don't know where DE comes from.

Do we believe supermassive black holes formed all at once, from super super super massive stars half the size of a galaxy?   The math of the weight of galaxies shows the supermassive black hole in the center is about half the total weight of a galaxy.   Never heard anyone weigh in on this issue.

The Milky Way (ours) is one of the larger spiral galaxies known.   We've seen evidence that Andromeda is larger and heading this way with an apparent intent to merge.    Do such supper massive black holes only merge at such time of a royal cluster f**k? or only a long long long time after.  I think the super massive ones like to do it a lot and provide evidence they carry the weight to show it, and probably get the job done quick.  But there's a lot of variables to take into consideration, with little time to study such slow processes, we haven't been watching long enough to know much of a thing.

LIGO showed evidence wine little ones do at size of event horizons touch, they merge and become silently black thereafter.  (I'm reading a little more into their evidence than what they've stated).

LIGO has only been searching for a little while, since it was upgraded to a detectable resolution.  It spotted it happen quickly thereafter.   One sample is impossible to base any real statistical analysis on, conclusions???  we got lucky???   Time will allow statistics to develop.  Hard to hurry up and wait.

So I really don't know what we know.  I know what I postulate.   I try hard to refrain mixing ideas in either direction.  Not always possible.

From what I understand, we know very little about very little amounts of space that might otherwise contain a hole lot of 0 time still/moving weight.

BB & lambda DM started from the point of a singularity resolving to infinity.  Its historical trivia, yet undeniable fact.  Nobody who practices Lambda-CDM philosophies wants to admit it, they don't, they just accept it...  and move on.  Trying to find more reasons to add to an infinity of change to an infinity problem that resolves infinity the same no matter what you do...
« Last Edit: 02/04/2016 11:32:02 by JoeBrown »
Does everything simple always gotta be so complex?

#### jeffreyH

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##### Re: Could merging black holes be more common than previously expected?
« Reply #4 on: 02/04/2016 11:16:44 »
If you consider gravitational anomalies due to density variation then it wouldn't be surprising if more than one dense mass resulted from a single collapse. In fact that appears to be a very good theory.

#### jeffreyH

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##### Re: Could merging black holes be more common than previously expected?
« Reply #5 on: 02/04/2016 11:36:52 »
If we take the expression $$\frac{\hbar^2k^2G}{c^2r_s}$$ and have r replace rs then as r approaches rs we could model a multi-region collapse. I think.

#### evan_au

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##### Re: Could merging black holes be more common than previously expected?
« Reply #6 on: 02/04/2016 11:51:25 »
Quote from: JoeBrown
Do we believe that super nova events happen often, at a fairly regular frequency?

Wikipedia says: " supernovae are relatively rare events within a galaxy, occurring about three times a century in the Milky Way".
They are expected to be random, rather than regular, but even random events can have an average rate.

Quote
Do we believe supermassive black holes formed all at once, from super super super massive stars half the size of a galaxy?
It is thought that supermassive black holes formed from the aggregation of smaller black holes. A single star half the mass of a galay is most unlikely.
It is thought that stars in the early universe could have been as heavy as 100 times the mass of the Sun.
The abundance of elements like Carbon, Nitrogen & Oxygen in the universe has been enhanced by previous supernovae; this lets protostellar disks today radiate energy much more efficiently, so much smaller stars can form today.

Quote
the weight of galaxies shows the supermassive black hole in the center is about half the total weight of the galaxy.
I have heard of one case (M60-UCD1) where the supermassive black hole is 10% the mass of the galaxy, but this is a significant outlier.

In general, the supermassive black hole is thought to be about 0.1% of the mass of the central galactic bulge. For spiral galaxies, this bulge is in turn a fraction of the galaxy mass. See: https://en.wikipedia.org/wiki/M%E2%80%93sigma_relation#Importance

Quote
The Milky Way (ours) is one of the larger spiral galaxies known.   We've seen evidence that Andromeda is heading this way with an intent to merge.    Do such supper massive black holes only merge at such time .... or only a long long long time after?
The debris from the collision of the Milky Way and Andromeda are expected to pass through each other a couple of times before they coalesce. Each pass is likely to take hundreds of millions of years. The merger of the central supermassive black holes would happen long after this.
« Last Edit: 02/04/2016 12:01:42 by evan_au »

#### acsinuk

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##### Re: Could merging black holes be more common than previously expected?
« Reply #7 on: 02/04/2016 17:09:16 »
The LIGO labs are using 2  lasers at right angles with extreme accuracy and can detect a low frequency magnetic vibration that is transversely unequal.  This could have been caused by an internal fluctuation inside the single magnetic hub at the centre of a every galaxy, which is commenly called a super massive black hole.
A.C.Stevens

#### JoeBrown

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##### Re: Could merging black holes be more common than previously expected?
« Reply #8 on: 02/04/2016 17:55:53 »
The LIGO labs are using 2  lasers at right angles ...

This is in essence how Michelson-Morely went about trying to solve the aether question.  Different problem, no laser, but so similar in construction otherwise, makes it hard not recognize similarities.

I'm distracted from verifying my brief summary and lack of accuracy.  It poses a question that's somewhat pertinent, yet not.  Cannot remember is if the right angle in the two experiments use the same beam and reflection?  I don't believe LIGO uses a two way light splitting reflective mirror on 45 degree angle to make two into one.

Michaleson Morley was looking for friction in what's now considered space-time or where gravity waves propagate. They concluded no.  LIGO simply looks for waves, no friction and modified the experiment accordingly to make that possible, it appears.

I don't know a lot about LIGO, just the basic premise, has been important to me.  Tho the results are cool too, when I find an explanation that doesn't require math to understand   Soundwave visualization / frequency distribution showed me what I *think* I need to know.  Amazing how little information from that can mean a black hole lot.
Does everything simple always gotta be so complex?

#### JoeBrown

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##### Re: Could merging black holes be more common than previously expected?
« Reply #9 on: 02/04/2016 18:13:11 »
If we take the expression $$\frac{\hbar^2k^2G}{c^2r_s}$$ and have r replace rs then as r approaches rs we could model a multi-region collapse. I think.

You've got me at a disadvantage.  I'm working toward understanding the math aspects, I've ignored for a long time.  I like concepts and how they relate.  Math is a bugger tho.  I understand its the simplest form of concept solidification.  But we don't know a lot about black holes because of a single infinity solution that's derived from multiple different values equaling the same solution in GR, which is the black hole.

That in and of itself, is the simplest form of a thesis I'm still in progress of postulating.

Black holes have brought a lot of speculation into their singular solution.  I'm no Einstein, just one who admires him thru trying to understand what he did (and didn't do).  While I'm good with math (to an extent).  I want to finish explaining relativity where Einstein didn't.  Its what he didn't explain about infinity that I wish he had, w/respect to GR.  He created GR w/out knowing about the infinity solution...  He was told after others realized.  Left us all w/out completion by the author and a few BH mysteries to figure out, w/out his insight.

r & s = radius & size?  nuff said.
« Last Edit: 02/04/2016 19:44:20 by JoeBrown »
Does everything simple always gotta be so complex?

#### JoeBrown

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##### Re: Could merging black holes be more common than previously expected?
« Reply #10 on: 02/04/2016 19:40:38 »
Wikipedia says: " supernovae are relatively rare events within a galaxy, occurring about three times a century in the Milky Way".
They are expected to be random, rather than regular, but even random events can have an average rate.

To me, there's a few things a statistics course made quite clear.
• If a thing happens once, it will likely happen again.
• The larger the sample set the better it will describe the population as a whole
• frequence and distribution are what statistics help postulate to sense.

We can't watch a galaxy form, so we cannot build a strong case for how they've been constructed.  But we've got a lot of them to look at, so we know more than one thing happened many times., or so it seems.

Quote
It is thought that supermassive black holes formed from the aggregation of smaller black holes. A single star half the mass of a galay is most unlikely.
It is thought that stars in the early universe could have been as heavy as 100 times the mass of the Sun.

100 times the sun, is close to the smallest possible black hole.

Billion times a billion sized the sun I believe have been witnessed in our galaxy.  Hard to say, Pop-Sci as a source leaves a lot of specifics out when trying to show how little we know.  I think it's in our galaxy, but I don't know.   How can a star contain so much mass it almost instantly has to become a hole?  How could one form so late in the game, and avail it for us in relatively short period of it's life span.

Defining whats' known and with many unknown unknown's, makes what can be known, unclear.

Quote
I have heard of one case (M60-UCD1) where the supermassive black hole is 10% the mass of the galaxy, but this is a significant outlier.

We've seen evidence of galaxy merge from many different views of many different instances we presume are the beginning, middle and end results.

Quote
In general, the supermassive black hole is thought to be about 0.1% of the mass of the central galactic bulge. For spiral galaxies, this bulge is in turn a fraction of the galaxy mass. See: https://en.wikipedia.org/wiki/M%E2%80%93sigma_relation#Importance

One thing we won't be able to see by definition of how it might operate is a supermassive black hole formation.  A body of mass could form so large it could skip the igniting process that burns as a star.  We don't know, can't know but can speculate (- goes to resolving unknown unknown's).

I suspect this would indicate it's a young galaxy with little time for black hole aggregation.  But I suspect a lot of different things, I w/no proof, it's speculation, not known.

Quote
The debris from the collision of the Milky Way and Andromeda are expected to pass through each other a couple of times before they coalesce. Each pass is likely to take hundreds of millions of years. The merger of the central supermassive black holes would happen long after this.

I think all that's right, or agree.  But it's a span of time we can only speculate, having only samples of variation of results that might have been exactly such.

I don't want to conclude I know what we don't know.  I don't know how that could be qualified as "right".
I think I know one thing we don't, which has caused me, and others,  a lot of confusion.  I hope I can better clarify soon.  I've got a paper to write.  Might publish it in the "theories" section.

Thought I had it figured out when I posted "Is Dark Energy a Farce?"   I'm confident I'm on the right track, but there's so many issues to one unexplained unknown, it's hard to make sense out of only half.  All at once, even harder, I'm working on it.  Many tangents of thought make it hard to be precise and clear...
Does everything simple always gotta be so complex?

#### evan_au

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##### Re: Could merging black holes be more common than previously expected?
« Reply #11 on: 02/04/2016 22:49:13 »
Quote from: acsinuk
LIGO labs are using 2  lasers at right angles with extreme accuracy and can detect a low frequency magnetic vibration
the single magnetic hub at the centre of a every galaxy, which is commonly called a super massive black hole
LIGO detects gravitational waves, not magnetic waves.

It is thought that the plasma of the accretion disk around a black hole could produce magnetic fields.
Experiments with high speed X-Ray telescopes suggest that there could be instability in the accretion disk around a black hole.  If there are changes in the mass circling the event horizon, that may possibly produce weak gravitational waves.

Quote from: JoeBrown
I don't believe LIGO uses a two way light splitting reflective mirror on 45 degree angle to make two into one.

Yes, it does use a 45° mirror. The phase is arranged so that there is no light reaching the detector in the absence of gravitational waves.
A slight change in length results in a big change in light reaching the detector.
See: https://en.wikipedia.org/wiki/LIGO#Operation

Quote from: JoeBrown
100 times the sun, is close to the smallest possible black hole.
The estimated size of the black holes detected last year was around 30 solar masses each.
The smallest size of a stellar-mass black hole is thought to be 3-4 solar masses.
See: https://en.wikipedia.org/wiki/Black_hole#Gravitational_collapse

There is a hypothetical possibility that there may have been atom-sized black holes formed in the big bang, but that is just speculation at this time.  Of more significance for the formation of supermassive black holes is that there may have been very large black holes formed in the big bang.
See: https://en.wikipedia.org/wiki/Black_hole#Primordial_black_holes_in_the_Big_Bang

#### JoeBrown

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##### Re: Could merging black holes be more common than previously expected?
« Reply #12 on: 03/04/2016 08:00:38 »
LIGO detects gravitational waves, not magnetic waves.
...
I knew that...  !:o!

I've been quite distracted lately.  Fear I'm loosing it...  Anxiety almost abated has replenished, with difficulty recognizing any bounds.  (I can barely stop thinking with poetic thought, nearing magnitude 10 crazy thoughts, I think therefor I know not what to believe.)

I *think* I found a big link between GR & QM.  I can't wait for others to laugh (bzzt, the fool I don't wish to believe I've become, yearning to scream loud).

FWIW, if someone else has made the link and I've not paid enough attention to news.  Now would be a really nice time for anyone who might know, to urge me to comprehend my tardiness to the game.

Quote
Yes, it does use a 45° mirror. The phase is arranged so that there is no light reaching the detector in the absence of gravitational waves.
I thought so.  Been distracted, like I said.  I knew Michaleson Morley's work was very poignant early on.  When I read about LIGO, I had a hard time keeping track of many similarities they share.  Yet differing objectives were clear, coincidental thoughts ran together a while ago.  Fun tho, working it out.  Been a while tho.

Quote
There is a hypothetical possibility that there may have been atom-sized black holes formed in the big bang, but that is just speculation at this time.  Of more significance for the formation of supermassive black holes is that there may have been very large black holes formed in the big bang.

Been on a quest to prove an argument with myself, waged for at least 3 years.

I concluded about a week ago, to quit.  I argued on scienceforums with some folks that hammered my ignorance in my face.  I enjoyed arguing with them.  Didn't mind their attempts at belittling me.  Then I came up with a prediction.  Wasn't very clear, but they closed the thread I started.  I wrote a guy I thought was a "sysop" and he reopened the thread so I could post my prediction...  I pointed to the one here.  Then thought of a way to predict w/out waiting for a SN gravity wave to pass us to possibly prove me right or wrong.

Given random distribution of SN events, I'll probably be dead...  So thought it prudent to search for another method.  After letting my thoughts run wild on the thread, right after I thought of how to describe the prediction so it would be clear and while I was typing it in the closed the thread and snubbed it in my face.

I posted the prediction here of my "new theory" Dark Energy and set out to write some math and finish my only work so I could quit w/the anxiety, get over my stupidity, and move on.

Mmm Fffft.  I hit the link.  I think I've really got one nobody knows. Grrr.....  Almost finished the paper.  It's not very scientific like.  Doesn't matter.  I'm Flipped, but I may be right.  Once it's published, can't wait, probably won't be.  After its submitted, I'll post it.  Then I can quite worrying, right/wrong won't matter.  I'll quit worrying.  But I'm so scared I'm forgetting something....

Oh, I hate BB theory!
(not the show, I like that a lot).  I had to rule out many premises in and of it to concoct my thesis...  Its got a real bad taste in my mouth and it has to change if I'm right.  I can only speculate on a magnitude of probabilities, for moments because I'm too close to finish, to worry about details of many unrelated yet connected issues.

Micro black holes aren't possible(, according to me).  Part of my work, I cannot go into much more specific detail at this time.  If I'm right I'm right (and a lot of Lambda-CDM will change).  If I'm wrong, nobody cares...  Neither change a whole lot of anything really, but that's not whats important.  I want to know more about black holes, that's where I got lost, had to stray from Lambda-CDM accepted lines of thought.

Wish I could think about anything else for a while...  Put in 15 hours today working only on the paper.

Another 15 tomorrow and I might be finished.  But I'm scared to show it to anyone :-/  Every will ask, who does this fool think he is...   LOL.   Einstein?  Maybe I am, if I could believe in re-incarnation changing names so unique to common....  W31rd S. might happen.  Not too likely tho.  I don't believe I'm him.  But his work made my thoughts possible.  That I know.  I have tremendous respect a man I'll never be able to know otherwise, tho I still wish I could yap w/him.

Please accept apologies (everyone) I am sorry for going off topic. But I've been in a lone argument too long, which finally sees a clear path to finalization.  Crazy thoughts can only bounce around in one head for a little while before problems arise.

Doh, sorry again!-)

I banked up on sleep for a while before I let anxiety be a problem (of sort).  Went from 1 pot of coffee a day to ~4~ now.  I'm gonna break if I cant get back to 1.  Sleep's been banked for this issue to reach a amicable conclusion.  Thoughts stray when sleep isn't managed properly and the stress kills.  On my mind but kinda irrelevant.  Voicing thought is a necessary reminder.   Even if it is to a texted base Internet voice, it's gotta be freed of hidden harms.

I realize I may have queued a moderator warning.  FWIW; I've tried to suggest looking into a fix for "find out more" links returning blank pages.  Before you decide to errr.. aah.. ban me... aahhh...  I might be right.  I probably have delusions of  https://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect .  I am aware.  However barring chances that I'm wrong.  If I tie GR & QM together this site might spike in activity.  Check'n p's & q'z might be in order first.  Yeah, I defiantly over analyze w31rd stuff that only seems to matter about matters that only seem to matter to me.

I really need a sleeping pill, but a psychological fear of changing chemistry in ways that aren't possible to correct, provide allergic fear presently not within (my) experimental boundries.
« Last Edit: 03/04/2016 08:46:37 by JoeBrown »
Does everything simple always gotta be so complex?

#### evan_au

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##### Re: Could merging black holes be more common than previously expected?
« Reply #13 on: 06/04/2016 22:47:51 »
Quote from: JoeBrown
I think you need to link to the paper
I found the draft: Electromagnetic Counterparts to Black Hole Mergers Detected by LIGO
http://arxiv.org/abs/1602.04735
Quote from: Abraham Loeb
...if the BH binary detected by LIGO originated from two clumps in a dumbbell configuration that formed when the core of a rapidly rotating massive star collapsed.
The author suggests that a star rotating this fast would probably have arisen from the earlier merger of two smaller stars.