M87's Black Hole 2 to 3 times larger than initial estimate --- now 6.4 billion solar masses.
So if we assume that every black hole is twice as large as original estimates ... then does it follow that the additional mass starts to negate how much "dark matter/energy" is needed to make the (revised) Standard Model work?
G'day from the land of ozzzzzzzz
The standard model does not work, God knows why its called a standard. Maybe scientists need something to hide behind and make them feel right.
M87 has been known for years to be much heavier, the issue was to be able to confirm the readings. A better understanding of compact matter.
The next 4 years we will be able to get a better reading with the very large telescope and the upgrade of the hubble.
More info on M87
http://hubblesite.org/search/?query=m87
The standard model does not work, God knows why its called a standard. Maybe scientists need something to hide behind and make them feel right.
M87 has been known for years to be much heavier, the issue was to be able to confirm the readings. A better understanding of compact matter.
The next 4 years we will be able to get a better reading with the very large telescope and the upgrade of the hubble.
More info on M87
http://hubblesite.org/search/?query=m87
Harry Costas
It's called the standard BECAUSE it works very well indeed, passed all the experimental tests and has been confirmed over and over. Perfect, no, but mostly correct, yes. Just like Newton was the standard of gravitation until Einstein came along and refined it. This is not going to change because Harry doesn't understand it.
uaafanblog
It's called the standard BECAUSE it works very well indeed, passed all the experimental tests and has been confirmed over and over. Perfect, no, but mostly correct, yes. Just like Newton was the standard of gravitation until Einstein came along and refined it. This is not going to change because Harry doesn't understand it.
uaafanblog
So if we assume that every black hole is twice as large as original estimates ... then does it follow that the additional mass starts to negate how much "dark matter/energy" is needed to make the (revised) Standard Model work?
Hardly, the mass of the BH is only about 4% of the mass of the galaxy. The observations(IE rotational curves) concerning Dark Matter are true no matter what the mass of the galaxy is. Dark Energy has nothing at all to do with Dark Mass, just the same first name.
Grumpy
QUOTE
The standard model does not work, God knows why its called a standard.
It's called the standard BECAUSE it works very well indeed, passed all the experimental tests and has been confirmed over and over. Perfect, no, but mostly correct, yes. Just like Newton was the standard of gravitation until Einstein came along and refined it. This is not going to change because Harry doesn't understand it.
uaafanblog
QUOTE (->
| QUOTE |
| The standard model does not work, God knows why its called a standard. |
It's called the standard BECAUSE it works very well indeed, passed all the experimental tests and has been confirmed over and over. Perfect, no, but mostly correct, yes. Just like Newton was the standard of gravitation until Einstein came along and refined it. This is not going to change because Harry doesn't understand it.
uaafanblog
So if we assume that every black hole is twice as large as original estimates ... then does it follow that the additional mass starts to negate how much "dark matter/energy" is needed to make the (revised) Standard Model work?
Hardly, the mass of the BH is only about 4% of the mass of the galaxy. The observations(IE rotational curves) concerning Dark Matter are true no matter what the mass of the galaxy is. Dark Energy has nothing at all to do with Dark Mass, just the same first name.
Grumpy
If indeed as Grumpy points out that these black holes at the cores of galaxies only make up 4% of galactic mass then I'd agree that you could double the size of every one of them and the universe would still be flying apart at an ever increasing rate ... according to the current incarnation of the Standard Model. It is the consensus in science at the moment. That gives it enough weight to be defended heartily.
And one day when it's confirmed that the universe is dramatically older and essentially static compared to today's theory, I'll gladly pass Grumpy a pre-moistened towelette to assist him in removing the egg from his face.
But that is not this day.
And one day when it's confirmed that the universe is dramatically older and essentially static compared to today's theory, I'll gladly pass Grumpy a pre-moistened towelette to assist him in removing the egg from his face.
But that is not this day.
G'day fior
Any dead long can float down mainstream, it takes no effort to agree with any standard model.
Science is about testing the water and if it means pain going upstream, thats life.
Imagine for one second that we all agreed. How boring!!!!!!!!!!!!!!!
We would have to agree to disagree.
The following is an interesting paper.
String dynamics and ejection along the axis of a spinning black hole
Authors: Ted Jacobson, Thomas P. Sotiriou
(Submitted on 20 Dec 2008 (v1), last revised 26 Mar 2009 (this version, v2))
Any dead long can float down mainstream, it takes no effort to agree with any standard model.
Science is about testing the water and if it means pain going upstream, thats life.
Imagine for one second that we all agreed. How boring!!!!!!!!!!!!!!!
We would have to agree to disagree.
The following is an interesting paper.
String dynamics and ejection along the axis of a spinning black hole
Authors: Ted Jacobson, Thomas P. Sotiriou
(Submitted on 20 Dec 2008 (v1), last revised 26 Mar 2009 (this version, v2))
QUOTE
Abstract: Relativistic current carrying strings moving axisymmetrically on the background of a Kerr black hole are studied. The boundaries and possible types of motion of a string with a given energy and current are found. Regions of parameters for which the string falls into the black hole, or is trapped in a toroidal volume, or can escape to infinity, are identified, and representative trajectories are examined by numerical integration, illustrating various interesting behaviors. In particular, we find that a string can start out at rest near the equatorial plane and, after bouncing around, be ejected out along the axis, some of its internal (elastic or rotational kinetic) energy having been transformed into translational kinetic energy. The resulting velocity can be an order unity fraction of the speed of light. This process results from the presence of an outer tension barrier and an inner angular momentum barrier that are deformed by the gravitational field. We speculatively discuss the possible astrophysical significance of this mechanism as a means of launching a collimated jet of MHD plasma flux tubes along the spin axis of a gravitating system fed by an accretion disk.
If you are trying to find a way to do-away with "dark matter", trying to look for more mass in more places is not the solution.
Yes, people say that the observable matter in the universe is about 90% lacking of what it must be. And yes, some or all of that may be explainable by normal matter which is simply obfuscated from our view by dust or by the event horizons of black holes.
But that is not what necessarily drives scientists to theorize about dark matter.
The biggest problem with gravity is when you look at rotating galaxies:
All the stars in a galaxy orbit around the galactic nucleus (the big black hole(s) in the center), right?
Well, logic would tell us that the stars closer to the center of the nucleus would be traveling faster. And that the stars at the edge of the galaxy would be orbiting slower.
They do, to an extent, but there is not as much difference in their speeds as there should be. It's as if the entire galaxy is almost rotating as one. Like a pinwheel with stars painted on it instead of individual stars revolving around the center at rates appropriate for their distances from the center.
I suppose in some ways, "dark matter" is a place holder to describe the cause for this observed effect.
Yes, people say that the observable matter in the universe is about 90% lacking of what it must be. And yes, some or all of that may be explainable by normal matter which is simply obfuscated from our view by dust or by the event horizons of black holes.
But that is not what necessarily drives scientists to theorize about dark matter.
The biggest problem with gravity is when you look at rotating galaxies:
All the stars in a galaxy orbit around the galactic nucleus (the big black hole(s) in the center), right?
Well, logic would tell us that the stars closer to the center of the nucleus would be traveling faster. And that the stars at the edge of the galaxy would be orbiting slower.
They do, to an extent, but there is not as much difference in their speeds as there should be. It's as if the entire galaxy is almost rotating as one. Like a pinwheel with stars painted on it instead of individual stars revolving around the center at rates appropriate for their distances from the center.
I suppose in some ways, "dark matter" is a place holder to describe the cause for this observed effect.
G'day Latro
It's not a question of dark matter.
It's the issue of reality.
Compact matter acts as a gravity sink that controls its surroundings. To understand compact matter is to understand the workings of the universe.
It's not a question of dark matter.
It's the issue of reality.
Compact matter acts as a gravity sink that controls its surroundings. To understand compact matter is to understand the workings of the universe.
Harry Costas
You should be aware that if our sun were replaced by a compact object of the same mass, the orbits of the planets would not change. Compact matter no more "controls" it's surrounding space than does the same mass of marshmellows.
Grumpy
You should be aware that if our sun were replaced by a compact object of the same mass, the orbits of the planets would not change. Compact matter no more "controls" it's surrounding space than does the same mass of marshmellows.
Grumpy
G'day Grumpy
I agree
I agree
G'day from the land of ozzzzz
This paper is interesting
http://www.cosmology.info/newsletter/2008.04.htm
Are old galaxies smaller, bigger or neither?
This paper is interesting
http://www.cosmology.info/newsletter/2008.04.htm
Are old galaxies smaller, bigger or neither?
QUOTE
Three new papers on galaxy size deepen the contradiction between expanding-universe predictions and measurements. Van Dokkum et al look at very massive galaxies at a redshift of about 2.3 and find that on average they are 5- 6 times smaller in radius and hundreds of times denser than massive galaxies in today’s universe. The densest of these high-z galaxies have densities five times that of any galaxies that now exist. The authors speculate that perhaps mergers may result in less dense galaxies, but mergers would also result in more massive galaxies, and some of the high-z galaxies are as massive already as the most massive galaxies observed today. So, if they merged, they would create galaxies larger than any we see. Since massive galaxies are easy to find, getting rid of either extremely massive or extremely dense galaxies is difficult, akin to hiding an elephant under a rug.
G'day, Harry.
QUOTE (Harry Costas+Jun 16 2009, 05:17 PM)
It's not a question of dark matter.
Can you please elaborate? I'm pretty sure the topic at hand is about dark matter.
Can you please elaborate? I'm pretty sure the topic at hand is about dark matter.
QUOTE (Harry Costas+Jun 16 2009, 05:17 PM)
It's the issue of reality.
Apologies, but I do not follow.
And of course, with regards to your other comment about compact matter, Grumpy is absolutely correct about that... so my question then becomes... if you agree with him, then what exactly were you trying to convey with your comment about compact matter controlling its surroundings differently than normal matter?
Thanks, and sorry I could not quite understand.
Apologies, but I do not follow.
And of course, with regards to your other comment about compact matter, Grumpy is absolutely correct about that... so my question then becomes... if you agree with him, then what exactly were you trying to convey with your comment about compact matter controlling its surroundings differently than normal matter?
Thanks, and sorry I could not quite understand.
G'day latro
It seems you have read the words out of context.
Dark matter is the unseen matter.
If we cannot see compact matter, Neutron matter, quark matter or matter that makes up the so called black hole. Than we call it dark matter.
Although dark matter can be defined to include objects that we cannot see such as planets.
http://arxiv.org/abs/hep-th/0502108
Controlling Chaos through Compactification in Cosmological Models with a Collapsing Phase
Authors: Daniel H. Wesley (1), Paul J. Steinhardt (1), Neil Turok (2) ((1) Princeton University, (2) DAMTP, CMS)
(Submitted on 11 Feb 2005 (v1), last revised 6 Sep 2005 (this version, v3))
It seems you have read the words out of context.
Dark matter is the unseen matter.
If we cannot see compact matter, Neutron matter, quark matter or matter that makes up the so called black hole. Than we call it dark matter.
Although dark matter can be defined to include objects that we cannot see such as planets.
http://arxiv.org/abs/hep-th/0502108
Controlling Chaos through Compactification in Cosmological Models with a Collapsing Phase
Authors: Daniel H. Wesley (1), Paul J. Steinhardt (1), Neil Turok (2) ((1) Princeton University, (2) DAMTP, CMS)
(Submitted on 11 Feb 2005 (v1), last revised 6 Sep 2005 (this version, v3))
QUOTE
Abstract: We consider the effect of compactification of extra dimensions on the onset of classical chaotic "Mixmaster" behavior during cosmic contraction. Assuming a universe that is well-approximated as a four-dimensional Friedmann-Robertson--Walker model (with negligible Kaluza-Klein excitations) when the contraction phase begins, we identify compactifications that allow a smooth contraction and delay the onset of chaos until arbitrarily close the big crunch. These compactifications are defined by the de Rham cohomology (Betti numbers) and Killing vectors of the compactification manifold. We find compactifications that control chaos in vacuum Einstein gravity, as well as in string theories with N = 1 supersymmetry and M-theory. In models where chaos is controlled in this way, the universe can remain homogeneous and flat until it enters the quantum gravity regime. At this point, the classical equations leading to chaotic behavior can no longer be trusted, and quantum effects may allow a smooth approach to the big crunch and transition into a subsequent expanding phase. Our results may be useful for constructing cosmological models with contracting phases, such as the ekpyrotic/cyclic and pre-big bang models.
G'day
I forgot this paper
http://arxiv.org/abs/physics/0005009
One a topological secret of gravity and its surprises for astrophysics, cosmology and particle physics
Authors: Zahid Zakir (CTPA)
(Submitted on 5 May 2000 (v1), last revised 8 Jun 2007 (this version, v3))
[Moderator: Stop posting in this style. Notes.]
I forgot this paper
http://arxiv.org/abs/physics/0005009
One a topological secret of gravity and its surprises for astrophysics, cosmology and particle physics
Authors: Zahid Zakir (CTPA)
(Submitted on 5 May 2000 (v1), last revised 8 Jun 2007 (this version, v3))
QUOTE
Abstract: It is argued that the surface radius of a compact source can not be less than its gravitational radius due to the strong gravitational time dilation effects. The such "topological" difference between the Newtonian and relativistic gravity leads to the known observable effects. The hierarchy of supercompact stars, more massive than neutron stars, such as heavy baryon, quark (subquark?) and other heavy particle stars is predicted instead of the black holes. The lack of the cosmological singularity and a gravitational nature of the regularizations of loop divergencies in quantum field theory are also discussed.
[Moderator: Stop posting in this style. Notes.]
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