Cosmological Model of The Universe

[OnlyMe]

Based on the definition supplied, a singularity could be anything from a point mass to a mass whose physical dimensions are just less than its associated event horizon. Both of these are likely extremes, with the true character and description residing somewhere in between. Still in either case, any credible description of a black hole, would also represent a description of a gravitational singularity, consistent with our current understanding and observations.

I don't think that is consistent with QM. And forgive my impertinence, but aren't (theoretical) singularities dimensionless? If so, then any object that occupies volume is not a singularity by definition.

I am not sure what is or is not consistent with QM. Certainly attempts to develop a model of quantum gravity have not yet been successful. Even GR is having some difficulties keeping up with our ever expanding observations at macrocosmic scales, I.e. the need for dark matter and dark energy, which remain an unknown.

But what was being discussed was the black hole and singularities. At least it was that portion of the discussion I was initially commenting on... And again anything that either GR or QM has to say about what lies within the event horizon remains theoretical.., in the extreme. Even much of what occurs at and just outside the event horizon, being beyond direct observation and/or experiment, must of necessity remain the subject of theory.

My earlier point was that singularity, within the context of this thread was poorly defined. Yes if one clearly states that the definition to be accepted here is confined to that of the theoretical application of GR, one could assume that a singularity is a point mass.., having no dimensions. But that is not the only definition even in physics of a singularity. There can easily be a difference between a singularity and a point singularity.

A singularity, within the context of physics, could be defined as a region of space or space-time where mass has reached an absolute or maximum density, rather than an infinite density. Two things follow from this. First, a region of space would not normally be thought of as a point, rather than a volume, and a singularity would then have some dimension. And second, substituting absolute or maximum for infinite, again allows that the singularity involved might have dimensions rather than exist as a dimensionless point. All we can really say with any degree of certainty supported by observation, is that whatever lies within the event horizon seems to prevent the escape even of light.

A popularized view of this from the standpoint of GR, is that the escape velocity within the even horizon is greater than the speed of light, so no light escapes. If light cannot escape, then nothing does... However (and I offer the following only as a thought experiment, not as an alternate model), it might be just as reasonable to assume that the conditions within the event horizon are such that photons are never generated.., that matter as we understand it does not exist as independent particles, in which case the escape velocity, or even effective gravitational force, would be no issue, as there would be nothing to escape. In either case what we see from the outside would be the same.., nothing including light escaping the black hole from inside the event horizon.

A long winded way around saying that the word singularity in physics, does not automatically mean "point" singularity, and it may in fact refer to a region of space/space-time which has some volume.

 

[KilljoyKlown]

A singularity, within the context of physics, could be defined as a region of space or space-time where mass has reached an absolute or maximum density, rather than an infinite density. Two things follow from this. First, a region of space would not normally be thought of as a point, rather than a volume, and a singularity would then have some dimension. And second, substituting absolute or maximum for infinite, again allows that the singularity involved might have dimensions rather than exist as a dimensionless point. All we can really say with any degree of certainty supported by observation, is that whatever lies within the event horizon seems to prevent the escape even of light.

A long winded way around saying that the word singularity in physics, does not automatically mean "point" singularity, and it may in fact refer to a region of space/space-time which has some volume.

"Maximum density" Is that a concept that applies to all BH's no matter how massive they might be? I find it very hard to believe a small solar sized BH has the same density as a supermassive BH of over a billion solar masses. Also, It seems like scientists should either quit using the term "singularity" or give it a definition that means the same thing to all of us so everybody is on the same page when it's talked about.

 

[KilljoyKlown]

I thought of this thread when I read the linked thread.

http://www.sciforums.com/showthread.php?133836-Black-Hole-Spins-At-Almost-The-Speed-Of-Light

Yes, when it comes to BH's there's never a shortage of things to observe and talk about.

 

[OnlyMe]

"Maximum density" Is that a concept that applies to all BH's no matter how massive they might be? I find it very hard to believe a small solar sized BH has the same density as a supermassive BH of over a billion solar masses. Also, It seems like scientists should either quit using the term "singularity" or give it a definition that means the same thing to all of us so everybody is on the same page when it's talked about.

Re: Singularity vs. point singularity; I don't believe "scientists", as in physicists have any real trouble understanding the context, any more than a lay person would have difficulty understanding the meaning of "home" when used in reference to a game or a dwelling. The problem usually comes up in lay oriented publications where a "scientist" may not be aware of the contextual issue, while immersed in the concepts of their own field... Or where a lay person, may not recognize the contextual differences when crossing the boundaries between differing scales and models. In this discussion the problem, seems to me, that the theoretical definition is being comparred or subjected to an attempt to describe how the physical or real material world works.

Theoretically, it likely does not matter whether a black hole is a point singularity or has some physical dimension. We do not observe the black hole itself, only it's affect on its surroundings, which may be the same reguardless of how we define the physical characteristics of the black hole, we cannot observe directly. In practical terms the same may not be true.

The following does not represent a developed model that I am aware of, and should be taken as a thought experiment only. What we do know of both gravity and matter through GR and QM, both are derived from locally defined observations and then projected into the theoretical environment inside the event horizon, of a black hole.

The maximum density lable should have come with a similar disclaimer as I offered later in the next paragraph, of my earlier post. Without knowing the exact mechanism which results in what we describe and experience as gravitation, it is difficult to truly know whether there is some mass density where a balance between the compression of gravitational force and any resisting (and likely subatomic or even on the scale of quark and gluon) force associated with mass density, balance one another.., or whether the gravitational force actually reaches some infinity overcoming all other forces.

We have become very good at describing what happens at both cosmological and quantum scales and somewhat less so at definning the mechanisms that result in the dynamic relationships we describe. If there is a mass density where the two forces do balance, the label absolute or maximum density could apply and it would not be unreasonable to think that an object, a black hole.., once reaching that threshold would do no more thnt increase in volume or size as its mass grows. All black holes would then be physically of the same mass density, with a volume anywhere from just,less than that of the event horizon to some smalle fraction of it.

 

[pywakit]

Re: Singularity vs. point singularity; I don't believe "scientists", as in physicists have any real trouble understanding the context, any more than a lay person would have difficulty understanding the meaning of "home" when used in reference to a game or a dwelling. The problem usually comes up in lay oriented publications where a "scientist" may not be aware of the contextual issue, while immersed in the concepts of their own field... Or where a lay person, may not recognize the contextual differences when crossing the boundaries between differing scales and models. In this discussion the problem, seems to me, that the theoretical definition is being comparred or subjected to an attempt to describe how the physical or real material world works.

Theoretically, it likely does not matter whether a black hole is a point singularity or has some physical dimension. We do not observe the black hole itself, only it's affect on its surroundings, which may be the same reguardless of how we define the physical characteristics of the black hole, we cannot observe directly. In practical terms the same may not be true.

The following does not represent a developed model that I am aware of, and should be taken as a thought experiment only. What we do know of both gravity and matter through GR and QM, both are derived from locally defined observations and then projected into the theoretical environment inside the event horizon, of a black hole.

The maximum density lable should have come with a similar disclaimer as I offered later in the next paragraph, of my earlier post. Without knowing the exact mechanism which results in what we describe and experience as gravitation, it is difficult to truly know whether there is some mass density where a balance between the compression of gravitational force and any resisting (and likely subatomic or even on the scale of quark and gluon) force associated with mass density, balance one another.., or whether the gravitational force actually reaches some infinity overcoming all other forces.

We have become very good at describing what happens at both cosmological and quantum scales and somewhat less so at definning the mechanisms that result in the dynamic relationships we describe. If there is a mass density where the two forces do balance, the label absolute or maximum density could apply and it would not be unreasonable to think that an object, a black hole.., once reaching that threshold would do no more thnt increase in volume or size as its mass grows. All black holes would then be physically of the same mass density, with a volume anywhere from just,less than that of the event horizon to some smalle fraction of it.

"Theoretically, it likely does not matter whether a black hole is a point singularity or has some physical dimension."

I think it might matter. Let's take a hypothetical BH with a 'core' physical diameter (not event horizon) of our solar system. Spin it at 1,000 RPS. Can you calculate the surface velocity at it's equator?

I have already demonstrated that if a BH had just the physical diameter of Earth, and was spinning at 1,000 RPS, it's equatorial surface would rotate past a fixed point in space at 133 times c.

While I agree that in 'normal' space, matter can't exceed c, but what do we really know about space inside the event horizon?

 

[jerryboy]

What youR thoughtful but mistaken atheist revisionist is that quantum fluctuations are somehow a analogy of creation. The very notion that quantum fluctuation which are contained within quantum vacuums are not analogous to the cosmic singularity. It contains a quantum of energy which can become a weak quantum particle at unpredictable time in any way compares to the emergence of the universe. From a one dimensional singularity of nothing the whole universe of everything that every was and currently is and will ever will be crossed the first slice of time called Planck time. Not only did all space emerge from this nothing, but the immaterial nature of time, which cannot be separated from space likewise emerged. To suggest that everything in the universe can be simply explained by the fraud of scientific understanding, breaking all known quantum and Einstein's and Newton's laws is a fraud of scientific arrogance. The creation of everything from nothing can only be explained by a entity who from outside of time and space, with unimaginable power, knowledge was the first cause of the universe. From ex-nihilo to everything is not just unexplained, but unexplainable by the naturalistic/materialistic paradigm. The instability of quantum vacuums in no way explains the emergence of the universe and any rational person with a little knowledge of cosmology and physics can easily understand this. This who entertain this fiction possess more faith than most Christians believe when they state that "God created the Heavens and the earth (The Universe). The failure of the scientific to explain the spontaneous emergence of the universe and the likewise astronomical chance of life emerging from chemistry remain within the unexplainable, not just the "gaps" of the the yet unexplained, because they represent the immaterial and and incredibly unlikely which science has not and will not be able to explain. As for Black holes there is no scientific evidence that these indirectly deduced phenomena have the potential of emerging into "mini" universes. While their internal masses slowly grow, most of the matter and energy of the galaxy are in balance with these unobservable entities. The lack of evidence, which is what science usually employs to evaluation its notion of reality, is particularly absent, so such speculation is no better than the religious expression of faith.

 

[paddoboy]

What youR thoughtful but mistaken atheist revisionist is that quantum fluctuations are somehow a analogy of creation. The very notion that quantum fluctuation which are contained within quantum vacuums are not analogous to the cosmic singularity. It contains a quantum of energy which can become a weak quantum particle at unpredictable time in any way compares to the emergence of the universe. From a one dimensional singularity of nothing the whole universe of everything that every was and currently is and will ever will be crossed the first slice of time called Planck time. Not only did all space emerge from this nothing, but the immaterial nature of time, which cannot be separated from space likewise emerged. To suggest that everything in the universe can be simply explained by the fraud of scientific understanding, breaking all known quantum and Einstein's and Newton's laws is a fraud of scientific arrogance. The creation of everything from nothing can only be explained by a entity who from outside of time and space, with unimaginable power, knowledge was the first cause of the universe. From ex-nihilo to everything is not just unexplained, but unexplainable by the naturalistic/materialistic paradigm. The instability of quantum vacuums in no way explains the emergence of the universe and any rational person with a little knowledge of cosmology and physics can easily understand this. This who entertain this fiction possess more faith than most Christians believe when they state that "God created the Heavens and the earth (The Universe). The failure of the scientific to explain the spontaneous emergence of the universe and the likewise astronomical chance of life emerging from chemistry remain within the unexplainable, not just the "gaps" of the the yet unexplained, because they represent the immaterial and and incredibly unlikely which science has not and will not be able to explain. As for Black holes there is no scientific evidence that these indirectly deduced phenomena have the potential of emerging into "mini" universes. While their internal masses slowly grow, most of the matter and energy of the galaxy are in balance with these unobservable entities. The lack of evidence, which is what science usually employs to evaluation its notion of reality, is particularly absent, so such speculation is no better than the religious expression of faith.

Oh gee here's another one!!!

The emergence of the Universe from this so called fictional state that scientists believe in is based on research, study and observations....
The faith that scientists do have in the methodology is a limited faith, sprinkled with the knowledge that modifications, changes, and alterations will almost certainly be forthcoming as observations see further, and as technical measuring equipment improves.
It bares no relation at all to a magical deity that immediatley short circuits any obvious questions about where that deity came from.
You are correct in your thoughts that we have no evidence that BHs may lead to other Universes, that certainly is just a hypothesis at this time, but one I'm personally attracted to.

The most relevant point I could inform you of is that if it wasn't for science, you might only have a life span of 25 years if you were lucky, and of course we would be emerged in even more magical deities, Santa Claus types of Gods and Omnipotent beings that have existed forever.

I know where my "faith" takes me.

 

[paddoboy]

With regards to the BH Singularity, mathematically speaking, it is the point at the center where our mathematics and models fail
Physically speaking that would be at the Planck scale, so as far as I know, a volume of the smallest allowable size.
By the way [and I think this supports my description] a BH is not infinite in itself, but it may lead to infinite quantities.
Personally speaking and just a gut feeling, I don't believe it will...Which means either we have a surface of sorts just below the Planck volume, [with the mass/energy in an unknown state] or hypothetically, at that scale a ERB is formed connecting two throats of a wormhole, one leading into our BH in question, and the other end an outpouring [White Hole] creating another baby Universe

 

[pywakit]

What youR thoughtful but mistaken atheist revisionist is that quantum fluctuations are somehow a analogy of creation. The very notion that quantum fluctuation which are contained within quantum vacuums are not analogous to the cosmic singularity. It contains a quantum of energy which can become a weak quantum particle at unpredictable time in any way compares to the emergence of the universe. From a one dimensional singularity of nothing the whole universe of everything that every was and currently is and will ever will be crossed the first slice of time called Planck time. Not only did all space emerge from this nothing, but the immaterial nature of time, which cannot be separated from space likewise emerged. To suggest that everything in the universe can be simply explained by the fraud of scientific understanding, breaking all known quantum and Einstein's and Newton's laws is a fraud of scientific arrogance. The creation of everything from nothing can only be explained by a entity who from outside of time and space, with unimaginable power, knowledge was the first cause of the universe. From ex-nihilo to everything is not just unexplained, but unexplainable by the naturalistic/materialistic paradigm. The instability of quantum vacuums in no way explains the emergence of the universe and any rational person with a little knowledge of cosmology and physics can easily understand this. This who entertain this fiction possess more faith than most Christians believe when they state that "God created the Heavens and the earth (The Universe). The failure of the scientific to explain the spontaneous emergence of the universe and the likewise astronomical chance of life emerging from chemistry remain within the unexplainable, not just the "gaps" of the the yet unexplained, because they represent the immaterial and and incredibly unlikely which science has not and will not be able to explain. As for Black holes there is no scientific evidence that these indirectly deduced phenomena have the potential of emerging into "mini" universes. While their internal masses slowly grow, most of the matter and energy of the galaxy are in balance with these unobservable entities. The lack of evidence, which is what science usually employs to evaluation its notion of reality, is particularly absent, so such speculation is no better than the religious expression of faith.

Apologies for my absence ...

I will freely admit there are questions for which I have no answer. I can not explain the mechanism(s) ... if indeed there were any ... that would have allowed matter to 'clump' out of such minute particles emanating from the fabric of space. Nor can I explain how space ... infinite space ... and it's 'inherent' energy could have existed eternally. That said, I have simply tried to describe how the Hubble volume that currently exists might operate on the large scale, and by extension, the infinite universe (if such an artifact exists) beyond the Hubble volume, staying within the parameters established by the laws of physics. Laws that appear to exist wherever we look in the universe.

I do not think our universe emerged from 'nothing' nor do I think all the matter/energy of the Hubble volume caan occupy zero volume ... the theoretical mathematical singularity. I don't think the universe will allow this. I also do not think the Hv was created by colliding extradimensional 'branes'. This hypothetical scenario is fraught with problems ... such as zero observational evidence of strings, vaccua in the neighborhood of 10^530, and perhaps the biggest problem of all, a requirement to explain how these branes got their energy. And further, if these colliding branes did release the energy equivelent of the Hubble volume 13.7 billion years ago, what mechanism shut off the spigot? Making matters worse for 'stringers' I believe recent data coming from the LHC has put a serious damper on that 'theory'.

As difficult as it is to grasp an infinite and eternal space, it is much harder for me to accept the 'eternal, omnipotent god' hypothesis. It just isn't plausible. If we had, over the course of the last few decades, observed phenomena that do not conform to known laws of physics, the only reasonable explanation for the phenomena being 'magic' then I would have to seriously reconsider my position on this issue. But that has not happened.

Recapping, I do not for a moment accept our universe sprang forth from nothing, nor for that matter, from a singularity. I think a reasonable explanation, based on current science, is that the Big Bang was the centrifugal release of energy from a spinning hyper-sized black hole, containing all the m/e observed in the universe.

Besides ... the Christian god of the bible was far too ignorant of the universe we observe today to be omniscient. Having studied the bible off and on for over half a century, it seems far too coincidental that He didn't know any more than the people of that day knew. Or thought they knew.

Do you really think the stars were created after the earth? I don't.