The Naked Scientists

The Naked Scientists Forum

Author Topic: Black holes combining?  (Read 1864 times)

Offline eternity

  • Jr. Member
  • **
  • Posts: 27
    • View Profile
Black holes combining?
« on: 21/03/2014 14:24:54 »
If there is a black hole at the center of our galaxy and the same in all others, is it possible that eventually they could engulf the entire galaxy creating a super dense amount of matter with a huge amount of gravity/energy/mass?

If (in theory) this did happen, would black holes begin attracting each other (in the same way atoms did in the early universe to eventually make stars/planets etc. even though there are huge amounts of 'space' between them)?

What I'm asking is I suppose, what is the possibility of one super black hole existing that would be powerful enough - with all the combined energy of the universe, collapsing in on itself and creating one singularity that could potentially lead to another big bang at some point?

(I'm very sorry if my question seems insane - but I genuinely would like to know if this idea is feasible, so please humour me. Thank you).
« Last Edit: 21/03/2014 14:26:59 by eternity »


 

Offline DanielB

  • Full Member
  • ***
  • Posts: 88
  • Humanity working as one, for continual life.
    • View Profile
Re: Black holes combining?
« Reply #1 on: 21/03/2014 14:59:08 »
Some physicist believe that the black holes are just that holes,, and would (merge).  I myself believe, they have a solid core, just on the basis of gravity doing what gravity does.  Would they just merge? 

Take two gravitational fields,, high density rotating cores and bring them together,, you will have a violent reaction at some point.  They would act like black holes on each other,, pulling,, fighting each other.  Their gravitational fields are designed to break matter down to the atomic level.

(hence spaghettification) Hper gravity acts on all matter the same way. 

The Milky Way galaxy,, and Andromida galaxy are on a collision course.  It's probably about 3 billion years from now,, but that will be a sight to see.  Will Andromida consuem the Milkyway?  Its twice our size.

Will those black holes,, just merge?  From what I see,, not a chance,,, they will act as they are,, stealing material from the other till their gravitational fields,, get so close.   They theorize,, the hole would just get bigger  of they merged,, however,, (the moment) you stay within the realm of physics.  Instead of the gateway.      Just think in you mind,, two solid core's infinate gravity,, No,, the ones that hold galaxies,, wouldnt just,, merge.

Now,, the smaller one's?  Say,, 20 miles wide,, those,, the reaction,, wouldnt be as violent,, and quite theoretically possible,, those, get pulled in,, their gravity slowed,, due to the size comparison of the Super Massive one's,, till they were consumed.. This to me ,, has a much greater chance of happening,, and growing them that way,, vs.. Larger one's meeting and colliding for the merge..  The event, would be the greatest energetic event ,, ever seen.  To me that is,,

I had to add my two coppers worth.  Love the question

DanielB

 

Offline evan_au

  • Neilep Level Member
  • ******
  • Posts: 4101
  • Thanked: 245 times
    • View Profile
Re: Black holes combining?
« Reply #2 on: 21/03/2014 21:18:56 »
Galactic black holes have a major impact on the life history of a galaxy - but they don't seem expand to to engulf the entire galaxy.

The stars orbiting a galaxy have considerable angular momentum, and according to physics, angular momentum is conserved in interactions, so it won't suddenly disappear. While stars retain this angular momentum in a roughly circular orbit, they won't fall into the black hole.

In disk-shaped galaxies like the Milky Way, astronomers find a link between the observed size of the galactic bulge and the estimated size of the galactic black hole - the black hole is just a small percentage of the mass in the galactic bulge.

This may be because if the galaxy has an actively eating black hole, it forms an accretion disk, and magnetic fields in the swirling plasma create powerful jets that blast much of the accretion disk out of the galaxy, forming the distinctive twin lobes of a radio galaxy.

It is thought that an active galactic nucleus will also heat up gas in the galactic bulge, and drive this gas away, halting new star formation in this region. So there is a feedback control mechanism which limits the growth of black holes.

Models of galactic mergers are harder to simulate on computers, but given our future involvement in a galactic collision, they are an area of active research  (eg do two merging spiral galaxies form an elliptical galaxy, and does the elliptical galaxy eventually settle down to a combined disk-shaped galaxy? What is the effect of two galactic black holes merging?)
« Last Edit: 22/03/2014 08:51:33 by evan_au »
 

Offline Pmb

  • Neilep Level Member
  • ******
  • Posts: 1838
  • Physicist
    • View Profile
    • New England Science Constortium
Re: Black holes combining?
« Reply #3 on: 22/03/2014 03:57:33 »
Quote from: eternity
If there is a black hole at the center of our galaxy and the same in all others, is it possible that eventually they could engulf the entire galaxy creating a super dense amount of matter with a huge amount of gravity/energy/mass?
I don't see how. That's like asking whether all the planets will eventually fall into the sun.

Quote from: eternity
If (in theory) this did happen, would black holes begin attracting each other (in the same way atoms did in the early universe to eventually make stars/planets etc. even though there are huge amounts of 'space' between them)?
All black holes attract all matter, including other black holes. So the answer to whether a black hole will attract other black holes then the answer is yes.

Quote from: eternity
What I'm asking is I suppose, what is the possibility of one super black hole existing that would be powerful enough - with all the combined energy of the universe, collapsing in on itself and creating one singularity that could potentially lead to another big bang at some point?
The possibility is zero.
 

Offline Bill S

  • Neilep Level Member
  • ******
  • Posts: 1802
  • Thanked: 11 times
    • View Profile
Re: Black holes combining?
« Reply #4 on: 22/03/2014 14:58:12 »
Quote from: eternity
What I'm asking is I suppose, what is the possibility of one super black hole existing that would be powerful enough - with all the combined energy of the universe, collapsing in on itself and creating one singularity that could potentially lead to another big bang at some point?

Hopefully Pete will tell us why "The possibility is zero".

I have a problem with the idea of singularities forming.  If any feature (mass/spacetime curvature/density) becomes infinite, it would take infinite time to form.  In other words; it would never happen.  So I suppose I am saying the same thing as Pete, but possibly for a different reason.
 

Offline jeffreyH

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 3913
  • Thanked: 52 times
  • The graviton sucks
    • View Profile
Re: Black holes combining?
« Reply #5 on: 22/03/2014 20:47:43 »
What I'm asking is I suppose, what is the possibility of one super black hole existing that would be powerful enough - with all the combined energy of the universe, collapsing in on itself and creating one singularity that could potentially lead to another big bang at some point?

As Pete said the possibility is zero. Gravity is inverse square so the effect on distant objects wouldn't be enough to overcome the momentum of the expansion of the universe. Momentum in this case may be misleading though as it is the space that is said to be expanding. It leads to the same conclusion. One other observation is that the gravitational waves emitted by black holes are tricky to theorize.
« Last Edit: 22/03/2014 20:49:39 by jeffreyH »
 

Offline evan_au

  • Neilep Level Member
  • ******
  • Posts: 4101
  • Thanked: 245 times
    • View Profile
Re: Black holes combining?
« Reply #6 on: 23/03/2014 03:12:57 »
Quote
If any feature (mass/spacetime curvature/density) becomes infinite, it would take infinite time to form.

A black hole is finite in diameter, with a finite mass, a finite volume and a finite density (plus a finite electrical charge and a finite angular momentum).
I saw some early computational estimates that a black hole could form in as little as 12ms during a core-collapse supernova - but the computations were very complex.

Now whatever happens at the center of black hole is a matter of some speculation, and may well involve a singularity of infinite density, but it really doesn't affect the cosmos outside the event horizon, which only cares about the mass, charge and angular momentum of the entire black hole within the event horizon, which never reaches infinite density.
« Last Edit: 23/03/2014 11:15:33 by evan_au »
 

The Naked Scientists Forum

Re: Black holes combining?
« Reply #6 on: 23/03/2014 03:12:57 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums