Do black holes contain singularities?

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Profile Jordan Hardee

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Message 1779207 - Posted: 15 Apr 2016, 2:35:26 UTC

I've heard a number of different views on this issue, some think that they are singularities while some do not. I'm not sure what to believe.
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Message 1779272 - Posted: 15 Apr 2016, 10:34:23 UTC

You may have to link some articles. From what I understand you can not have an event horizon without a singularity. In this case the egg does come before the chicken. I think I remember reading somewhere that it is mathematically possible to have a singularity without an event horizon, the inverse is not possible. I don't have any links to support this though.

Of course there are a group who thinks that black holes and unicorn are all fairy tales but that is another subject.

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Profile William Rothamel
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Message 1779290 - Posted: 15 Apr 2016, 13:01:05 UTC - in response to Message 1779272.  

What is the definition of a singularity. It may only be mathematically true ?
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Message 1779333 - Posted: 15 Apr 2016, 16:38:06 UTC - in response to Message 1779290.  
Last modified: 15 Apr 2016, 16:42:37 UTC

What is the definition of a singularity. It may only be mathematically true ?

There are many definitions:)
https://en.wikipedia.org/wiki/Singularity

Simplified:
There are mathematically singularities
https://en.wikipedia.org/wiki/Singularity_(mathematics)
A point at which a given mathematical object is not defined or not "well-behaved", for example infinite or not differentiable.

And there are gravitational singularities
https://en.wikipedia.org/wiki/Gravitational_singularity
A region in spacetime in which tidal gravitational forces become infinite.
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Profile William Rothamel
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Message 1779493 - Posted: 16 Apr 2016, 2:23:15 UTC - in response to Message 1779333.  

Thank you

1/0 when an equation blows up or maybe the Dirac delta function?
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Message 1779518 - Posted: 16 Apr 2016, 3:37:20 UTC - in response to Message 1779493.  

Thank you
1/0 when an equation blows up or maybe the Dirac delta function?

Oh dear. The Dirac delta function...
I don't even know if that function explain anything in a dark hole.
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Profile Gary CharpentierCrowdfunding Project Donor
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Message 1779523 - Posted: 16 Apr 2016, 4:20:55 UTC

Well, we are assuming there isn't some force that acts to prevent the stuff in the center from becoming a singularity after it detaches from our universe. However that would be new physics to us.
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Message 1779801 - Posted: 17 Apr 2016, 0:59:07 UTC
Last modified: 17 Apr 2016, 0:59:29 UTC

Not that I have any links, but... I read (somewhere) that while a 'physical' singularity is the ultimate "goal" of all stars headed that way, the slowing down of time (due to their high gravity fields) means no black hole has- from our point of view outside- reached this stage, and "might" not in the lifetime of the universe.

The event horizon is just the point where any light, even that generated by a star before it actually finishes collapsing, heads back in. No completed singularity required.
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Message 1779917 - Posted: 17 Apr 2016, 17:13:48 UTC
Last modified: 17 Apr 2016, 18:13:12 UTC

It should perhaps not be forgotten that the Wikipedia has become a good reference for many of these subjects, including both the singularity, gravity itself and also the notion of time.

Here are some examples of the term singularity.

1/0 (or division by zero) when it comes to the subject of mathematics.

∞ (the symbol which is representing infinity).

In mathematical terms, infinity and the singularity could be more or less the same thing, or if not so, perhaps inversely so when compared to each other.

The singularity in a Black Hole is the ultimate place of nature. Here both space and time apparently ceases to exist.

The Event Horizon is the place in space close to the Black Hole where the energy being represented by radiation (or in fact elementary particles) are not able to escape at the speed of light because of the tremendous gravity force being found inside this area of space.

The forces of gravity being present near or around such a Black Hole is as a result of the singularity being found at the core or nucleus of such an object.

Therefore it could perhaps be an idea of viewing the Universe as being seen from the point of the singularity through the presence of gravity and not the opposite way around, which is the usual or common way of doing this.

Between the Event Horizon and the Black Hole itself should be an area of space which definitely is an exotic place when it comes to the phenomena which might exist.

Remember that the pressure of gravity inside the Event Horizon is higher than the forces of gravity that exists even in neutron stars.

Time is supposedly the fourth dimension, but time itself might not be explained by the laws of gravity alone.

Also the famous equation E=mc2 does not explain the notion of time, so for a possible explanation of at least time, you should refer to the article about Special Theory of Relativity in the Wikipedia.

The Special Theory of Relativity is not about Newton's Laws of Gravity or the similar at all.

Therefore you may not find that much information about the subject here either, because it is regarded as being a difficult study field even to mathematicians and physicists and the equations behind this subject, at times being called "Field Equations", are extremely difficult to understand, even for many people who are dealing with these subjects.

In the same way as Cosmology is trying to explain nature, at least the part of it which is related to macrocosmos, as well as other articles related to the Big Bang as well as the subject of gravity and finally time itself, is now being sought unified against theories related to the elementary of microcosmos and the forces, or perhaps equations behind the existence of these particles.

Or possibly it better should be microcosmos versus macroscosmos once again.

By means of both the Special and General Theory of Relativity, Einstein's contributions to the whole subject field as well as the more recent discoveries related to Quantum Mechanics and Quantum Theory are being sought unified into a single Theory, but the sad fact is that when such a thing is next being attempted, new elements of discovery are being introduced, making the whole matter even more difficult.

Similarly, there are also currently new theories being created based on recent discoveries about nature being made.

In order to try and unite the theory behind the four Fundamental Forces of Nature into one single Uniified Theory, or GUT (for Grand Unified Theory), physicists are currently introducing terms like Dark Matter and Dark Energy in order to better make any conclusions or otherwise determine whether the Standard Model is the better one when it comes to understanding both the elementary particles of microscosmos as well as the objects that are being found in space.

Not forgetting about the astronomers as well. I will get back at their contributions to the whole subject a little later.

I think this makes a brief summary of what is thought of as being current knowledge without going into all details.

Also it became 12 years oF running Seti@home, it could be added as well.

Edit: The server apparently had a small hiccup or two while posting, making it slightly more difficult this time.
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Message 1783378 - Posted: 29 Apr 2016, 4:19:30 UTC

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Message 1783913 - Posted: 1 May 2016, 7:39:27 UTC
Last modified: 1 May 2016, 7:41:07 UTC

Yes.

A black hole is a singularity.

It is the common destination of all matter passing through the event horizon of a Black Hole beyond which matters coherency ceases to exist, all quantum particles, subparticles, etc go back into a state of non relativistic time and combine back into the state of the universe prior to transparency when the big bang creating our known relativistic universe of dimension, space and time. A singularity is where space, time, and dimension cease. Infinite density and zero time and zero dimension....

The contention is that amalgamations of sufficient mass is needed in order to create a singularity and ultimately this is the fate of all matter in our universe. So all those Galactic clusters and whirlpools and the interim states of matter such as stars are all just on their way down the rabbit holes of black holes to zero time, zero dimension, with very little able to spew out from the gravitational loci but and occasional cosmic ray and neutrino that gathered sufficient energy before the event horizon....
Never engage stupid people at their level, they then have the home court advantage.....
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Message 1783946 - Posted: 1 May 2016, 14:30:53 UTC - in response to Message 1783913.  

The Hawking radiation can escape a black hole, even in a time longer than the life of the Universe. Now Hawking says that a computer simulation by Israeli scientists has proven him right and is waiting for a Nobel prize.
Tullio
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Message 1784013 - Posted: 1 May 2016, 17:20:13 UTC - in response to Message 1783946.  

Sure, what is Hawking Radiation ?

How do you measure it, define it, sense it?

I believe that Stephen Hawking needs to go to an event horizon and show us his so called radiation.. There isn't such a thing....

I believe that the only thing that escapes the event horizon is neutrinos and gamma radiation that are energetic enough to escape at a 90degree angle, these are formed in the soup at and above the horizon. Once beyond the event everything escapes no more and is then in a soup of no time, no mass, no dimension and frankly out of our existence as spatial, time locked, relativistic beings. Gone zilch nada back to the Alpha of pre existence

Stephen needs to prove his Radiation exists and quantify it... He's simply unable to do so except as a postulate..
Never engage stupid people at their level, they then have the home court advantage.....
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Message 1784033 - Posted: 1 May 2016, 18:09:17 UTC
Last modified: 1 May 2016, 18:30:59 UTC

Here is what I found in a short time:
Hawking radiation
Tullio
Also see "Physicists split by Hawking paper" by Davide Castelvecchi, in 'Nature" Vol. 529, 28 January 2016.
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Message 1784058 - Posted: 1 May 2016, 19:23:40 UTC

Hawking Radiation is part of the process when virtual particles are created from the vacuum of space.
They always comes in pair.
When they are created there is always a possibility that one of them goes outside the event horizon but the other one stays in the black hole.
But it means that the Black Hole "evaporates" (loosing mass) in the long run.
It takes many trillions of years to do that.
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Message 1784107 - Posted: 1 May 2016, 22:41:08 UTC

A second search in a pile of papers on my desk found a good review article, always on "Nature" magazine:
"Fire in the hole" by Zeeya Merali in Vol.496, 4 April 2013.
One is always dubious about linking "Nature" articles on line, so I prefer to print those which interest me, but this increases the volume of paper on my desk. I have two printers, a Canon MX390 and a HP Envy 4500. This second is a networked printer, so I can print on it from all my PCs, also networked. Things have progressed since using dot-matrix printers to print UNIX manuals.
Tullio
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Message 1784355 - Posted: 2 May 2016, 23:26:55 UTC
Last modified: 3 May 2016, 0:13:49 UTC

Look up, tullio, not down.

Thanks for reminding me about the elephants.

But here there perhaps could be more to it.

Back tomorrow.
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Message 1784362 - Posted: 3 May 2016, 0:11:07 UTC - in response to Message 1784107.  

A second search in a pile of papers on my desk found a good review article, always on "Nature" magazine:
"Fire in the hole" by Zeeya Merali in Vol.496, 4 April 2013.
One is always dubious about linking "Nature" articles on line, so I prefer to print those which interest me, but this increases the volume of paper on my desk. I have two printers, a Canon MX390 and a HP Envy 4500. This second is a networked printer, so I can print on it from all my PCs, also networked. Things have progressed since using dot-matrix printers to print UNIX manuals.
Tullio

Tullio
To us who doesn't like piles of papers on the desktop:)
http://www.nature.com/news/astrophysics-fire-in-the-hole-1.12726
Hawking’s argument basically comes down to the observation that in the quantum realm, ‘empty’ space isn’t empty. Down at this sub-sub-microscopic level, it is in constant turmoil, with pairs of particles and their corresponding antiparticles continually popping into existence before rapidly recombining and vanishing. Only in very delicate laboratory experiments does this submicroscopic frenzy have any observable consequences. But when a particle–antiparticle pair appears just outside a black hole’s event horizon, Hawking realized, one member could fall in before the two recombined, leaving the surviving partner to fly outwards as radiation. The doomed particle would balance the positive energy of the outgoing particle by carrying negative energy inwards — something allowed by quantum rules. That negative energy would then get subtracted from the black hole’s mass, causing the hole to shrink.

Some more on the fabric of reality and the holographic principle.
http://www.nature.com/news/theoretical-physics-the-origins-of-space-and-time-1.13613
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Message 1784733 - Posted: 4 May 2016, 15:51:33 UTC
Last modified: 4 May 2016, 16:03:43 UTC

Yuri Millner has beaten the Nobel Foundation and awarded 1 million dollars to the three LIGO Founding Fathers, Ronald W.P.Drever, Kip S.Thorne and Rainer Weiss. Other two millions will be divided between the 1012 signers of the discovery paper in Physical Review Letters.
Tullio
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Message 1785492 - Posted: 7 May 2016, 12:00:41 UTC

I found this Q&A about black holes and singularities.
https://www.quora.com/If-there-is-no-matter-in-a-black-hole-then-where-does-the-mass-and-the-gravity-come-from
We do not know what is really or what happens at the so-called singularity. We do not know if it is meaningful to say that the matter is "there at the singularity" or not. The nature of spacetime near the singularity gets so distorted that it is hard to even tell what common concepts are meaningful or not. In particular the time distortion gets so important that common concepts such as "matter existence" may become tricky. Some hypothesis say that the space dimensions become gradually more time-like and the time dimension becomes more space-like, until they become undistinguishable or even reverse into each other, whatever that might mean. So it could be that the matter ceases to exist dimensionally "in space" and exists only "in time".

Kip Thorne also refute the common misconception that black holes are extremely compact and dense objects.
Black holes are "empty".
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