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Singularity- shouldn't the article have more theories?

It is logical that black holes consist of quarks, other "exotic" non-nuclear plasma, and energy. It is probably baloney that black holes are a singularity, infinitely small, with infinite temperature. Rules of physics still work in a black hole: there is equilibrium and pressure balance. Temperatures would be very high and would start at 200 MeV minimum (for nuclear disintegration and quark production) and go well into the TeV region. Exotic particles would be generated until there is pressure balance. Note that most effective mass might be in the form of photon energy, although these would have a very short mean free path before being absorbed and re-emitted. So most of the mass in our universe, if its in the form of black holes, could be in the form of energy. Note that likely any particle in the black hole, no matter how small, would have almost the same energy as the largest quark, similar to tokamak plasmas where the electron and proton energy is about the same.

Perhaps a black hole could become unstable and explode, but it is more likely that a black hole explosion would occur by instability when 2 black holes of approximate similar mass merge. Evidence for this are in a few galaxies where some enormous explosion fills the whole galaxy. These explosions are centered in the galaxy. And what's in the center of a galaxy?

So a black hole, inside the event horizon, has temperature, pressure, size, shape, probably a strong magnetic field, angular momentum, and effective mass summation, all of which can be described by physics. It is poor logic (Hawkins?) to state a black hole has infinite temperature and no size. - BG —Preceding unsigned comment added by 172.162.170.182 (talk) 01:16, 1 February 2010 (UTC)

Beyond a certain point, it is impossible for degeneracy pressure to support _any_ material, due to relativistic effects. Above a certain finite mass, probably in the neighbourhood of 4 solar masses, your "quark plasma" would have zero radius. You are also overlooking the event horizon, which is unrelated to the type of matter that forms the black hole. If any given amount of mass is compressed within a given radius (the schwarzschild radius), all rays from the future light-cones at any point within that radius point inwards (i.e., in the direction of decreasing radius). Further shrinking is as inevitable as moving forward in time, as there are literally no timelike paths that do not fall further inwards. Result: collapse to a singularity. There are reasons to believe that this picture is modified when the resulting object is sufficiently small (Planck radius), but your argument doesn't touch on this. Instead, you're ignoring the two points I noted above.

Alternatives to black holes that are considered plausible by the scientific community are already mentioned in the article. --Christopher Thomas (talk) 02:28, 1 February 2010 (UTC)

I don’t dispute that energy is contained in the system and light does not escape, but doubt that a black hole's mass-energy structure has zero size or infinite temperature. Light-cones in the outer shell point inwards, except near the center where there is zero or little net gravitational force, just intense pressure (which they add to). The great increase in temperature could provide pressure balance through radiation pressure alone, not even counting for particle pressure or angular momentum. If temperatures were high enough for neutron disintegration, quarks and other particles would form at a temperature of roughly 2000 GK, resulting in a radiation pressure increase of Ten to the 13th power more than a base temperature of 1 GK, which would prevent collapse. Einstein didn’t believe a black hole has zero size. - BG —Preceding unsigned comment added by 172.162.21.153 (talk) 16:00, 23 February 2010 (UTC)

Light cones at all points within the event horizon point inwards. Radiation pressure can't stabilize things, as there is no way for photons to move outwards to apply such pressure on outer layers of your hypothetical ball of plasma! This applies to all methods of transmitting force (force-carrying particles travel at the speed of light or slower). It can be at 1 GK, 1 TK, 1 PK, or the Planck temperature - it still falls inwards.

As for your other statements, the acceleration applied by gravity grow stronger as you move inwards - you'd only get "zero or little net gravitational force" if you were inside a distributed mass, not approaching a pointlike mass. You are correct in noticing that, at the exact center, there is no "inward" direction in which to go; that's part of why this type of situation is called a "singularity" (from mathematical singularity, a "singularity" is a region in which the equations describing a system cease to have well-defined values). At all points besides the exact, geometric center of the hole, the description given by general relativity is well-defined, and has the properties I described above. --Christopher Thomas (talk) 19:57, 23 February 2010 (UTC)

What I was saying is that it is a distributed mass, with a core where light bounces around. Outside the core light heads inwards, the opposite of a conventional star where light heads outwards. I doubt gravity could overcome a force that increases with the fourth power. - BG

You can doubt away all you want, but you might want to leave classical physical intuition behind and actually study GR to understand why what you are saying is flawed. TimothyRias (talk) 16:26, 24 February 2010 (UTC)

Einstein understood GR and didn’t believe a black hole has zero size. —Preceding unsigned comment added by 172.130.31.39 (talk) 17:29, 24 February 2010 (UTC)

He believed that the presence of a singularity in the mathematical description of black holes in GR meant that that description wasn't accurate. That doesn't mean he thought your description was right. Why not look up things that he did propose as alternatives? --Christopher Thomas (talk) 19:55, 24 February 2010 (UTC)

Your proposed structure still fails. Consider a shell of matter of some finite thickness, with a hollow region inside with your photons. At the outer edge of the shell, matter experiences exactly the same gravitational forces as if all of the enclosed mass was a point mass. Per the description above, this means all light-cones on the outermost layer of the shell point inwards, which causes two things to happen. First, the outside edge of the shell contracts as inevitably as moving forward in time (there are no allowable paths that do not result in contraction). Second, the outermost layer of the shell can feel no forces whatsoever from inside itself, because there is no way for force-carrying particles (or any other particles) to propagate outwards towards it. This violates one of the assumptions made by your hypothesis (that the whole structure ends up being stable with a fixed radius), showing that your assumptions are inconsistent (i.e., that it's impossible for a relativistic object to behave in the manner you propose). --Christopher Thomas (talk) 19:53, 24 February 2010 (UTC)

Your statements are logical and I do not have a satisfactory counter arguement at this time. Mathematically everything inside the event horizon should head inwards. Perhaps gravity does not scale linearly, but this smacks of cop-out logic. Perhaps there is a limit to energy density with a given mass. Perhaps radiation pressure overcomes gravitational contraction. We agree on something basic - as the mass contracts, temperature rises. I just think there is something illogical about a singularity. - BG —Preceding unsigned comment added by 172.129.141.65 (talk) 05:46, 28 February 2010 (UTC)

I agree that having the model predict singularities is unsatisfactory. It's usually taken to mean that the model being used is incomplete. Scientists studying the topic still disagree about what an accurate mathematical description of a black hole would be. Some of the proposals are linked from this article. --Christopher Thomas (talk) 08:39, 28 February 2010 (UTC)

One year after the claimed Big Bang the universe was smaller than the Schwarzchild radius, but it did not collapse. How is that explained? - BG —Preceding unsigned comment added by 172.130.18.247 (talk) 14:46, 2 March 2010 (UTC)

This is not a page to discuss black holes or GR. Nor is it a page to educate you in physics or cosmology. Your question is answered by inflation and reheating. TimothyRias (talk) 15:25, 2 March 2010 (UTC)

I'd kind of like to know why the Big Bang was able to expand, and did not collapse under its own gravity. Can that point be covered in the article, or a link provided to an explanation elsewhere. Misplaced Pages is for educating the masses. When somebody comes here and asks a question like this, it may indicate a gap in the article's coverage. Jehochman 15:34, 2 March 2010 (UTC)

That is a question that should (and is) be answered in the Big Bang article. It basically is the question if the density of the universe is above or below the critical density. If it is above the whole universe would (eventually) collapse in to a singularity known as a Big crunch. The reason that this hasn't happened is that the universe was never (far) above the critical density. (This has to do with inflation and reheating, etc.) But all these questions have only very tangentially to do with black holes (and the only real relation is the formation of GR singularities), they clearly fall beyond the scope of the article. TimothyRias (talk) 10:39, 4 March 2010 (UTC)

Actually, that wasn't the question. The question is how it was possible for the universe to expand, given that when you're sufficiently close to the Big Bang, density should have been high enough for any given region to have a Schwarzschild radius smaller than the observable universe, and so inevitably collapse rather than be able to expand.

The only answer I can think of is that the assumption in the last sentence doesn't hold, and that at any given time space was expanding quickly enough that the "observable universe" was smaller than the Schwarzschild radius of uniformly-distributed matter at that density, but having actual confirmation of that from a source would be nice. --Christopher Thomas (talk) 19:24, 4 March 2010 (UTC)

In the end that is basically what the critical density argument comes down to. The critical density is basically the density at which the Hubble and Schwarzschild radius coincide. With the caveat that you should be careful about what you mean with "radius" in an expanding universe. This indeed means that universe was never "small than the Schwarschild radius" making the original question. Also fundamentally this a question that should be and is adressed in the big bang and FRW metric articles, not in the black hole article. TimothyRias (talk) 20:33, 4 March 2010 (UTC)

If there are forces that can make a black hole expandexplode, then surely there are also forces that can prevent it from compressing to zero size. - BG —Preceding unsigned comment added by 172.129.209.75 (talk) 21:22, 6 March 2010 (UTC)

There also are no forces that can make a black hole expand, so your point is moot. TimothyRias (talk) 23:40, 6 March 2010 (UTC)

Not sure what you mean by forces that "can make a black hole explode". My best guess is that you are referring to evaporation of black holes due to Hawking radiation. But that is a quantum gravitational effect, there are no classical forces involved. (In case you didn't know the concept of "force" does not make sense on the quantum level.) It is quite generally assumed that quantum gravitational effects will also prevent the formation of a singularity. This is mentioned several times in the article. TimothyRias (talk) 15:18, 7 March 2010 (UTC)

I don't think he's referring to that. Near as I can tell, he saw "expansion of space prevents the universe from becoming a black hole" in preceding paragraphs, and jumped on that as a mechanism for his own conjectures about black holes from earlier in this thread.

Short answer is, "no, nothing known can magically make cosmic inflation or other metric expansion of space start within a black hole or within collapsing matter that will become a black hole". Starting within a black hole wouldn't do anything detectable anyways (from the outside, it'll always look like a black hole once it forms; you'll just get a disconnected baby universe inside). --Christopher Thomas (talk) 20:40, 7 March 2010 (UTC)

I think an example of black holes exploding is an explosion that fills the whole galaxy. - BG —Preceding unsigned comment added by 172.162.58.231 (talk) 17:01, 8 March 2010 (UTC)

Where exactly are you getting this? It doesn't seem to be based on any known properties of black holes or of galaxies. If you're talking about quasars, they're very hot accretion discs around very massive black holes. --Christopher Thomas (talk) 17:14, 8 March 2010 (UTC)

2 subjects: (1) Probably my mistake on an explosion filling a galaxy. An old source said M82 looked like it had an explosion that filled the galaxy, and it does look that way. Now its said M82 had an encounter with another galaxy that caused it, so I will read up on it. (2) If "It is quite generally assumed that quantum gravitational effects will also prevent the formation of a singularity.", why does the article say " the singular region has zero volume. It can also be shown that the singular region contains all the mass of the black hole solution." —Preceding unsigned comment added by 172.129.17.73 (talk) 21:23, 11 March 2010 (UTC)

The second statement refers to the description of black holes provided by general relativity. Under general relativity, you can show that all matter inevitably collapses to a region (point, line, or ring) of zero volume containing all of the mass of the hole. General relativity's description is not expected to be exact (though it seems to work very well as an approximation). Quantum gravity is expected to change the picture of what happens near the singularity (in a system where volume is quantized, regions of zero volume probably can't occur). --Christopher Thomas (talk) 22:20, 11 March 2010 (UTC)

The paragraph you are quoting from starts of with the clause "... as described by general relativity ...", in which context does statements can be proven rigorously. The last paragraph of that section discusses that the appearance of singularities in GR singles that the theory is incomplete. Please let us known if you find that last paragraph unclear, and if so what you think is unclear about it. We can then try to fix it. TimothyRias (talk) 08:59, 12 March 2010 (UTC)

Size Distribution Graph?

Intermediate-mass black holes appear to be much less common than stellar-size black holes and also rarer than galaxy-sized black holes. But how much rarer? It would be very useful to include a table, or preferably a graph, showing the number of black holes detected or predicted at each order of magnitude from the smallest detected hole size to the largest --Tediouspedant (talk) 13:31, 7 February 2010 (UTC)

It would be silly to create such a graph because black holes are still largely theoretical. --Cryptic C62 · Talk 17:04, 7 February 2010 (UTC)

On the contrary, we can certainly create a graph that lists compact objects of various mass ranges. Without major modifications to both general relativity and quantum mechanics, these would represent black holes or objects very much like them. If you insist on a caveat, call them "black hole candidates" rather than "black holes". The mass is something that can be directly measured, so there should be no problem with considering the data points in the graph factual. --Christopher Thomas (talk) 22:36, 7 February 2010 (UTC)

A good solution. The other problem: From where do we get our data set? Is there a database somewhere that lists black hole candidates and their masses? Anything other than that would be incomplete or WP:OR. --Cryptic C62 · Talk 23:25, 7 February 2010 (UTC)

Another issue I see is whether to plot the number of known candidates or the expected number of appearance. The first number would be terribly misleading since it very skewed by observational bias. There is also the issue of what counts as a candidate. The second would be more feasible as a graph. Expected frequencies of stellar mass black holes should be available from stellar evolution models, and a quick search on the archive shows quite some literature on the demography of supermassive black holes, but I think very little is known about the frequency of intermediate mass black holes. If they exist they could by quite a bit more frequent than the supermassive variety, but there are only vague ideas about how these form and thus about how many to expect.

To produce such a graph we basically would need a source that does this for us, since anything else would lead very much to WP:SYNTH territory. A quick look on the arxiv has produced little of promise but I'll keep my eyes open.TimothyRias (talk) 08:48, 8 February 2010 (UTC)

I agree that a plot of observed candidates would suffer from observation bias, but I'd also expect distributions based on models to be shown to be inaccurate as those models get revised (in particular, accretion models for IMBHs and SMBHs are still under active debate, last I heard). My best suggestion would be to put a dashed line indicating the expected distribution, with histogram bars for actual observations, and caveats about both sets of values in the caption/image description.

I don't have any useful suggestions about finding distribution data, as I don't follow the relevant literature. --Christopher Thomas (talk) 18:03, 8 February 2010 (UTC)

Citation needed

The article states "Roger Penrose proved that a singularity will form..."

Shouldn't such a fundamental statement be cited or is this so non-controversial that it can be stated as fact ? —Preceding unsigned comment added by 172.162.40.212 (talk) 23:39, 10 February 2010 (UTC)

It is widely accepted as fact (it's actually one of the more important results about black holes), but I agree that it should be cited. --Christopher Thomas (talk) 23:51, 10 February 2010 (UTC)

Maybe't it should also be stated that black holes can not combine inside the event horizon; since they are singularities they just orbit each other. —Preceding unsigned comment added by 172.164.76.224 (talk) 01:09, 11 February 2010 (UTC)

The same effect that causes matter to collapse to a singularity, would also force two singularities of a merging black hole to collapse into each other. Inside a certain radius (4/3 the Schwarzschild radius, if memory serves), moving tangentially pushes you inwards instead of outwards. Inside the horizon, _all_ timelike directions point inwards. --Christopher Thomas (talk) 03:52, 11 February 2010 (UTC)

Sidis' 1920 views on "black body" stars

Anyone know why William Sidis's 1920 views on "black body" stars (black holes) and "boundary surface" (event horizon) isn't in the history section:?

• The Animate and the Inanimate —Preceding unsigned comment added by 68.23.161.224 (talk) 08:49, 24 February 2010 (UTC)

As far as I can tell, it has had no impact (or real relation) to the developement of the theory of black holes.TimothyRias (talk) 09:38, 8 March 2010 (UTC)

Timothy, I appreciate your reply to the above query (even though I did not ask the question). This type of neutral reply gets the point across without causing unnecessary tension. Steve Quinn (formerly Ti-30X) (talk) 21:00, 8 March 2010 (UTC)

On Black Hole Formation alternate hypothesis.

Black hole formation

Let's talk about the improvement of the article. I think how the article is written now, causes a misunderstanding of how the formation works. From the viewpoint of the falling observer the collapse of a star happens in finite time, but from the viewpoint of the external observer, the matter is frozen just above the horizon, due to the dilation of the time. For the understanding of black holes it's crucial that the both viewpoints be more emphasized, either in the "Properties and structure" or the "Formation and evolution" section. Currently there is a only a sentence in History/General Relativity section. What do you think? Prot D (talk) 19:46, 14 March 2010 (UTC)

I agree that this issue is somewhat underrepresented at present. I think there are two possible locations to add a paragraph about this in the article: 1) in the event horizon section right after the discussion of gravitational redshift. 2) As a last paragraph of the intro of the formation and evolution section. A third option would be to add it as a footnote somewhere, but that doesn't seem quite right.

Also, does anybody know a reliable modern source that discusses this issue directly? This would be very helpful in providing references for whatever we decide to write. TimothyRias (talk) 09:30, 15 March 2010 (UTC)

I'd be surprised if it wasn't in MTW somewhere. --Christopher Thomas (talk) 17:19, 15 March 2010 (UTC)

I've added a paragraph to the gravitational collapse section with a link to an article by Penrose. Would you have a look to see if it is clear, and check for any mistakes. TimothyRias (talk) 16:38, 18 March 2010 (UTC)

I've tweaked the phrasing a bit. I also added a caveat about most of the energy emission happening early. The energy emission mechanism is mostly thermal emission from hot accreting matter, with some energy invested in polar jets as well, but adding detail about that would have unnecessarily bloated the paragraph. The only other caveat that I can think of is that the last light seen by a distant observer is actually seen in a finite length of time, as past a certain point it's possible to show that there isn't enough energy left to emit a photon of the appropriate temperature, if I'm remembering correctly. I left this out because I don't have a reference for it handy, and it would also have cluttered the paragraph (your description covered all of the points that would be confusing to a layman).

Long story short, looks good, and I made minor tweaks. Thanks for digging up the reference. --Christopher Thomas (talk) 18:02, 18 March 2010 (UTC)

Black hole and singularity

The section singularity descibes the center of a black hole as a point of infinite density. I don’t know much about general theory of relativity . But I think the concepts of black hole and singularity are quite different concepts. After all Pierre Simon Laplace knew nothing about general relativity and infinite densities ; but still he could postulate the black hole.

The Schwarzschild radius is ,

${\displaystyle r_{sc}={\frac {2\cdot G\cdot M}{c^{2}}}}$

When the mass of a non rotating black hole is given in terms of its volume and the overall density it can be seen that there are two creterias for an object to be a black hole; the Schwarzschild radius and the critical density.

${\displaystyle \rho \cdot r_{sc}^{2}=C}$

Here ρ is the critical density, r_sc is the Schwarzschild radius and C is a constant. (~1.6 10 SI units) . It is obvious from this relation that, for bigger objects, the critical density for being a black hole decreases. For solar mass the critical density can be as high as 1.85 * 10 kg/m .But a spherical object with a radius of one light year becomes a black hole with a minute density of 1.8 mgr/m . For galactic dimensions the overall density approaches to near vacuum. I find it quite difficult to reconcile the idea of singularity to such low density super big black holes. Nedim Ardoğa (talk) 08:07, 9 March 2010 (UTC)

First note that Laplace's idea (or rather John Michell's idea) of a dark star is somewhat different from a black hole. For example, the dark star idea does not prohibit rocket aided escape, etc. It is somewhat of an (un)lucky coincidence that the radius of a dark star and the Schwarzschild radius coincide exactly, since this prompts people to think that the concepts are the same.

The average "density" of a black hole can indeed be quite low for very mass BHs, however the causal structure imposed by general relativity on the interior of the black hole makes the creation of a singularity inevitable. (This is the essence of the Hawking-Penrose singularity theorems) The formation of the singularity can take a while if the BH is big enough. For example, if you'd take a black hole of the Hubble radius (average density around 1 atomic mass per cubic meter) the actual collapse could take billions of years.

Note that the article does not define a black hole as a singularity, but merely notes that the description of BHs in general relativity necessarily contains a singularity. TimothyRias (talk) 09:12, 9 March 2010 (UTC)

Straw poll: talk page notice

As we've had a few recent extended off-topic threads about peoples' personal ideas about how black holes work, and as this has happend fairly frequently in the past, I floated the idea at WT:PHYS about putting a banner on this page along the lines of the one at the top of Talk:Big Bang. This would direct people towards suitable venues for proposing their own models, while making it clear that this talk page isn't the best venue.

Response at WT:PHYS was positive, so I'm opening a straw poll here to see if implementation should go forward. A draft copy of the Big Bang notice-blurb, tweaked for use with the black hole article, is at Talk:Black_hole/noticeblurb.

Suggestions for suitable forum links are appreciated; I'd like to be able to point users in useful directions, rather than just say "not here".

What are all of your thoughts on this? --Christopher Thomas (talk) 22:52, 10 March 2010 (UTC)

Votes/Comments

• Support addition of such a notice, as long as useful links to other venues are provided (I don't have any). --Christopher Thomas (talk) 22:52, 10 March 2010 (UTC)
• Support don't care what it says, we can tweak it later. --Michael C. Price 23:13, 10 March 2010 (UTC)
• Support It seems like a useful tool, which would allow the Wikiproject physics editors to have the best use of their valuable time and attention. I certainly don't see this as overkill. Steve Quinn (formerly Ti-30X) (talk) 00:23, 11 March 2010 (UTC)
• Support unpublished personal theories should not clog up the talk page, when there are so many published crank theories already that could better clog up the talk page. 70.29.210.242 (talk) 06:02, 11 March 2010 (UTC)
• Support/comment Such a banner would be useful. I should that there already is a "got a question? Don't ask here" banner at the top of the page. I like your formatting better though. (The old banner does have useful links you can salvage. TimothyRias (talk) 07:00, 11 March 2010 (UTC)

  I noticed the existing banner; I was going to keep it, with the new notice over it, much as with the ones at Talk:Big Bang. Good point re. links; my fallback option would be to tweak the proposed template to say "at any of the links below", but I was hoping for actual pointers towards alternative-physics forums where original material would be welcome, vs. Q&A forums where they'd meet more or less the same response as here. Harvesting the existing links is definitely an option, though! --Christopher Thomas (talk) 07:09, 11 March 2010 (UTC)

  Here is site where original material is welcome and allowed. It is a wiki. Wikinfo. "Wikinfo provides a platform for the meshing of encyclopedic material, original and creative work and public domain material to further education and information." "Wikinfo welcomes editors from Misplaced Pages and offers much more opportunity to edit freely. Original research and original ideas are welcome."

  Writing an article at Wikinfo is the same as writing an article for Misplaced Pages except OR and original ideas are acceptable content. The structure and software is either the same or very similar. ----Steve Quinn (formerly Ti-30X) (talk) 07:26, 11 March 2010 (UTC)

• Support - without comment. DVdm (talk) 07:44, 11 March 2010 (UTC)
• Support—I think it is a good idea. There are comparable notices on Talk:Earth about Mostly Harmless as well as the lack of coverage concerning young Earth creationism. It seems to cut down on the unhelpful noise a little. Likewise, some talk pages have notices about recurring themes. The Talk:Evolution page has a FAQ that includes past discussions.—RJH (talk) 17:48, 11 March 2010 (UTC)

Notice added. Links remain a question.

As the overwhelming consensus seems to be in favour of the notice, I added it (with "...at one of the forum links below" as placeholder-directions). If anyone knows where fringe/non-standard black hole theories are usually debated, by all means add a link. I've held off on listing WikiInfo, as that seemed on inspection to a) be fairly low-traffic, and b) be geared more towards non-verified descriptions of mainstream work than fringe work, but that impression could easily be mistaken (and of course I'm not the final arbiter of what goes into the template; I'm just one editor). I hope this is a useful starting point. --Christopher Thomas (talk) 08:15, 12 March 2010 (UTC)

The http://www.physicsforums.com/ site is fairly active. I've posted there before and received useful responses. There seems to be discussion of black holes under the astrophysics section, along with a few unconventional topic headings.—RJH (talk) 16:10, 16 March 2010 (UTC)

Essays by 204.52.246.120

 The newly established Mechanism-Revealed Black Hole Theory (MRBHT): based on the newly established and verified MRGT (= Mechanism-Revealed Gravitational Theory, P. 445 ~ 514, Ch.4B, reference #1), MRBHT is established (P. 541 ~ 548, 5.5, Ch.5B, reference #1).  MRBHT reveals the mechanism and identifies the essence of black holes, thus discovers the fundamental nature of black holes, for the first time in the history of physics and science. 
   The main points of MRBHT include: (i) the mechanism of MRBHT is that the existence of a hugely massive astronomical object reduces the scales of length (space) and time in its vicinity to such an extent that all visible lights become invisible, thus the essence of MRBHT is the tremendous reduction in the scales of length (space) and time.  (ii) The ratio of visible light boundary wavelength (Rvlb) is the ratio of lower to upper boundary wavelength of visible light, i.e., Rvlb = 380 nm/760 nm (or 390 nm/780 nm) = 1/2.   (iii) Zhao’s black hole radius (RZhao), being determined by satisfying the length scale and time scale equal to Rvlb, is the threshold radius that marks the boundary of a black hole on which entering visible light begins to become invisible, whereas leaving invisible light begins to become visible. 
Zhao’s black hole radius equation is provided as following (P. 543, reference #1) (but appeared here): 

 The key to understanding of MRBHT:  (i) the mechanism thus/and essence of MRBHT is the theoretical core of MRGT, because MRBHT is based MRGT. (ii) As long as you want to know why space and time are variable thus relative in gravitational field, you will readily understand MRBHT, because MRBHT tells the why.  (iii) As long as you have known the greatest equation in the history of science, which is Einstein’s famous mass-energy equation (E = mc2 or E0 = mc2), you will easily understand MRBHT, because the law of object’s mass doing work (P. 93 ~ 109, Ch.1A, reference #1), which lays the foundation of MRBHT, also reveals the mechanism behind the greatest equation (P. 114 ~ 118, Ch.1B, reference #1). 

 The fundamentally profound applications of MRBHT: MRBHT is the key to solving the following fundamentally important problems in physics and astronomy, including:  the mystery of dark matter (P. 560 ~ 567, 5.7, Ch.5C, reference #1), the mysterious source of gamma ray bursts (P. 567 ~ 574, 5.8, Ch.5C, reference #1), the mysterious source of ultrahigh-energy cosmic rays (P. 574 ~ 577, 5.9, Ch.5C, reference #1), and the famous puzzle of GZK paradox (P. 578 ~ 580, 5.10, Ch.5C, reference #1), as well as the long-standing “black hole information paradox” (P. 580 ~ 582, 5.11.1, Ch.5C, reference #1). 

  Revealing the fundamental nature of black holes with the newly established Mechanism-Revealed Black Hole (MRBHT) (P. 541 ~ 548, 5.5, Ch.5B, reference #1).   . 
   MRBHT reveals the following fundamental natures of black holes (P. 544 ~ 548, reference #1). (i) The gravitational scales of space (length) and time increase radially outward from the central region of a black hole — first rapidly then slowly; and in the sequence of inside, on and outside Zhao’s black hole radius (RZhao), the gravitational scales of space (length) and time sequentially undergo the sub-regions of  < (1/2), = (1/2) and > (1/2) across the entire region of the black hole. (ii) Black hole bulk density decreases rapidly with the increase in the value of RZhao, and the concept of black hole bulk density demonstrates the mechanistically thus essentially feasible nature of MRBHT.  (iii) The constituents of black holes are not essentially unique (i.e., not essentially mysterious), comparing to other ordinary astronomical objects (P. 548, reference #1). (iv) Black holes can emit light, though the lights emitted from and by black holes are invisible within the boundary marked by RZhao.  (v) The visible lights that do not vertically travel towards a black hole are deflected away from the black hole (P. 546 ~ 547, reference #1).  The equation calculating black hole bulk density is provided as following (P. 546, reference #1)(though not appeared here): 

 The definition of black hole (i.e., mechanism-revealed black hole): a black hole is a region where, due to the existence of a hugely massive astronomical object, the gravitational scales of length (space) and time are reduced to such an extent that all visible lights entering the region become invisible and all lights emitted from and by the black hole are also invisible in the region (P. 547, reference #1).  In addition, based on the principle of gravitational light bending embedded on MRGT (= Mechanism-Revealed Gravitational Theory, P. 445 ~ 514, Ch.4B, reference #1), all visible lights not vertically traveling towards a black hole are deflected away from the black hole; more extensively, all visible lights, as long as not traveling towards the center of a black hole, are deflected away from the black hole by the gravitational scale contour lines of space and time in the gravitational field generated by the black hole. Stated plainly, a black hole is the region surrounding a hugely massive astronomical object that makes all visible lights become invisible via hugely reducing the scales of length and time around it. Stated loosely, a black hole is a hugely massive astronomical object that causes all visible lights to become invisible. 

Misplaced Pages is not the place to try to publish or popularize your own ideas. See WP:OR and WP:RS. --Christopher Thomas (talk) 19:02, 18 March 2010 (UTC)

Jehochman's Deletions

Fuzzballs

Jehochman removed this as OR. Fuzzballs are interesting recent work to resolve the singularity within string theory. There are dozens of very good references to this, although the language is suboptimal:

Fuzzballs

Fuzzballs are theorized by some superstring theory scientists to be the true quantum description of black holes. The theory resolves two intractable problems that classic black holes pose for modern physics:

1. The information paradox wherein the quantum information bound in in‑falling matter and energy entirely disappears into a singularity; that is, the black hole would undergo zero physical change in its composition regardless of the nature of what fell into it.
2. The singularity at the heart of the black hole, where conventional black hole theory says there is infinite spacetime curvature due to an infinitely intense gravitational field from a region of zero volume. Modern physics breaks down when such parameters are infinite and zero.

Fuzzball theory replaces the singularity at the heart of a black hole by positing that the entire region within the black hole’s event horizon is actually a ball of strings, which are advanced as the ultimate building blocks of matter and energy. Strings are thought to be bundles of energy vibrating in complex ways in both the three physical dimensions of space as well as in compact directions—extra dimensions interwoven in the quantum foam (also known as spacetime foam).

Wormholes

Yet again, without shame, he calls this 1940's result of Einstein and Rosen, verified and accepted for decades, original research.

Worm holes

General relativity describes the possibility of configurations in which two black holes are connected to each other. Such a configuration is usually called a wormhole. Wormholes have inspired science fiction authors because they offer a means to travel quickly over long distances and even time travel. In practice, such configurations seem completely unfeasible in astrophysics, because no known process seems to allow the formation of such objects.

Reversibility and Information loss

This material was deleted next: I don't know the precise source for this unlike the others, but I do know that it is well accepted material.

Reversibility and information loss

Black holes, however, might violate this rule. The position under classical general relativity is subtle but straightforward: because of the classical no hair theorem, it can never be determined what went into the black hole. However, as seen from the outside, information is never actually destroyed, as matter falling into the black hole takes an infinite time to reach the event horizon.

It should be pointed out that the equations of general relativity in fact obey T-symmetry, and given that the logic above comes from application of (classical) general relativity, one should be suspicious. This is due to the fact that it should not be possible to derive time-reversal-asymmetric conclusions from a time-symmetric theory (Loschmidt's paradox), which is general relativity in this case. Rindler coordinates, which apply near the event horizon for an observer "held" just outside the black hole, are T-symmetric and therefore there should not exist any such thing as an 'irreversible' process. It is possible that the 'paradox' is a result of applying time-asymmetric boundary conditions to the time-symmetric theory, making it a form of Loschmidt's paradox.

Ideas about quantum gravity, on the other hand, suggest that there can only be a limited finite entropy (i.e. a maximum finite amount of information) associated with the space near the horizon; but the change in the entropy of the horizon plus the entropy of the Hawking radiation is always sufficient to take up all of the entropy of matter and energy falling into the black hole.

Many physicists are concerned, however, that this is still not sufficiently well understood. In particular, at a quantum level, is the quantum state of the Hawking radiation uniquely determined by the history of what has fallen into the black hole; and is the history of what has fallen into the black hole uniquely determined by the quantum state of the black hole and the radiation? This is what determinism, and unitarity, would require.

For a long time Stephen Hawking had opposed such ideas, holding to his original 1975 position that the Hawking radiation is entirely thermal and therefore entirely random, containing none of the information held in material the hole has swallowed in the past; this information he reasoned had been lost. However, on 21 July 2004 he presented a new argument, reversing his previous position. On this new calculation, the entropy (and hence information) associated with the black hole escapes in the Hawking radiation itself. However, making sense of it, even in principle, is difficult until the black hole completes its evaporation. Until then it is impossible to relate in a 1:1 way the information in the Hawking radiation (embodied in its detailed internal correlations) to the initial state of the system. Once the black hole evaporates completely, such identification can be made, and unitarity is preserved.

By the time Hawking completed his calculation, it was already very clear from the AdS/CFT correspondence that black holes decay in a unitary way. This is because the fireballs in gauge theories, which are analogous to Hawking radiation, are unquestionably unitary. Hawking's new calculation has not been evaluated by the specialist scientific community, because the methods he uses are unfamiliar and of dubious consistency; but Hawking himself found it sufficiently convincing to pay out on a bet he had made in 1997 with Caltech physicist John Preskill, to considerable media interest.

more info loss

He continues his deletion with this, which I don't know the source for, but is well known folklore:

The loss of information in black holes is puzzling even classically, because general relativity is a Lagrangian theory, which superficially appears to be time reversible and Hamiltonian. But because of the horizon, a black hole is not time reversible: matter can enter but it cannot escape. The time reverse of a classical black hole has been called a white hole, although entropy considerations and quantum mechanics suggest that white holes are just the same as black holes.

The no-hair theorem makes some assumptions about the nature of our universe and the matter it contains, and other assumptions lead to different conclusions. For example, if Magnetic monopoles exist, as predicted by some theories, the magnetic charge would be a fourth parameter for a classical black hole

Taken together, these deletions make a strong case that Jehochman probably should brush up on the literature before making any more edits.Likebox (talk) 23:03, 20 March 2010 (UTC)

1. The smallest linear dimension in physics that has any meaning in the measurement of spacetime is the Planck length, which is 1.616252(81)×10 m (CODATA value). Below the Planck length, the effects of quantum foam dominate and it is meaningless to conjecture about length at a finer scale—much like how meaningless it would be to measure ocean tides at a precision of one centimeter in storm-tossed seas. A singularity is thought to have a diameter that doesn’t amount to even one Planck length; which is to say, zero.
2. "Hawking changes his mind about black holes". Nature News. doi:10.1038/news040712-12. Retrieved 2006-03-25.
3. "Black holes with magnetic charge and quantized mass" (PDF). Research Centre for High Energy Physics, School of Physics, University of Melbourne, Parkville 3052, Victoria, Australia. Retrieved 2009-03-24. {{cite web}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)

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