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What exactly is a black hole?

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  What exactly is a black hole? sam.wormley@gmail.com - 2019-02-18 07:31 -0800
    What exactly is a black hole? john <johnsefton288@gmail.com> - 2019-02-18 07:53 -0800
    600 trillion Suns bright, 12.8 billion years old. Jeff-Relf.Me  @. - 2019-02-18 12:31 -0800
      Re: 600 trillion Suns bright, 12.8 billion years old. pnalsing@gmail.com - 2019-02-18 18:02 -0800
        600 trillion Suns bright, 12.8 billion years old. Jeff-Relf.Me  @. - 2019-02-18 22:23 -0800
          Re: 600 trillion Suns bright, 12.8 billion years old. Martin Brown <'''newspam'''@nezumi.demon.co.uk> - 2019-02-19 10:28 +0000
          695 trillion suns, 12.5 billion years ago. Jeff-Relf.Me  @. - 2019-02-21 04:21 -0800
            695 trillion suns, 12.5 billion years ago. Jeff-Relf.Me  @. - 2019-02-21 06:32 -0800
    Re: What exactly is a black hole? Alan Folmsbee <omnilobe@gmail.com> - 2019-02-18 12:47 -0800
    Re: What exactly is a black hole? Serg Io <invvalid@invalid.com> - 2019-02-18 15:40 -0600
      Re: What exactly is a black hole? mitchrae3323@gmail.com - 2019-02-18 13:58 -0800
        Re: What exactly is a black hole? Serg Io <invvalid@invalid.com> - 2019-02-18 16:17 -0600
          Re: What exactly is a black hole? mitchrae3323@gmail.com - 2019-02-19 13:17 -0800
            Re: What exactly is a black hole? Serg Io <invvalid@invalid.com> - 2019-02-19 20:58 -0600
      Re: What exactly is a black hole? benj <benj.fake@gmail.com> - 2019-02-18 19:52 -0500
      Re: What exactly is a black hole? pnalsing@gmail.com - 2019-02-18 18:09 -0800
        Re: What exactly is a black hole? Serg Io <invvalid@invalid.com> - 2019-02-18 23:11 -0600
          Re: What exactly is a black hole? pnalsing@gmail.com - 2019-02-18 21:28 -0800
          Re: What exactly is a black hole? "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-02-18 22:45 -0800
    Re: What exactly is a black hole? Double-A <double-a3@hush.com> - 2019-02-19 14:15 -0800
      Re: What exactly is a black hole? "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-02-21 13:45 -0800
        Re: What exactly is a black hole? sam.wormley@gmail.com - 2019-02-21 14:24 -0800
          Re: What exactly is a black hole? john <johnsefton288@gmail.com> - 2019-02-21 16:42 -0800

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#727868 — What exactly is a black hole?

What exactly is a black hole?

"What is a black hole? In an article that has just appeared in the journal Nature Astronomy, LMU philosopher Erik Curiel shows that physicists use different definitions of the concept, depending on their own particular fields of interest.

"A black hole is conventionally thought of as an astronomical object that irrevocably consumes all matter and radiation which comes within its sphere of influence. Physically, a black hole is defined by the presence of a singularity, i.e., a region of space, bounded by an 'event horizon', within which the mass/energy density becomes infinite, and the normally well-behaved laws of physics no longer apply. However, as an article in the January issue of the journal Nature Astronomy demonstrates, a precise and agreed definition of this 'singular' state proves to be frustratingly elusive. Its author, Dr. Erik Curiel of the Munich Center for Mathematical Philosophy at LMU, summarizes the problem as follows: "The properties of black holes are the subject of investigations in a range of subdisciplines of physics – in optical physics, in quantum physics and of course in astrophysics. But each of these specialties approaches the problem with its own specific set of theoretical concepts."

"Erik Curiel studied philosophy as well as theoretical physics at Harvard University and the University of Chicago, and the primary aim of his current DFG-funded research project is to develop a precise philosophical description of certain puzzling aspects of modern physics. "Phenomena such as black holes belong to a realm that is inaccessible to observation and experiment. Work based on the assumption that black holes exist therefore involves a level of speculation that is unusual even for the field of theoretical physics." However, this difficulty is what makes the physical approach to the nature of black holes so interesting from the philosophical point of view. "The physical perspective on black holes is itself inextricably bound up with philosophical issues relating to ontological, metaphysical and methodological considerations," says Curiel."


Read more at: https://phys.org/news/2019-02-black-hole.html#jCp

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#727873

A black hole is spinning Space.
There is no matter in there of our size- our matter gets split into charges and shot out immediately- this has been seen: you sent me the link, Sam.

https://www.nasa.gov/mission_pages/swift/bursts/shredded-star.html

Gravity cannot increase to ridiculously huge amounts. A body of matter does not continuously send out some kind of negative radiation, while remaining completely unchanged as it does so, and then continue to send it out even if crushed to smithereens.

How does this make ANY sense?

Gravity is a MODULATION of a pre-existing FIELD (Odd likes fields), and as such a planets gravity is a ‘perturbation in the field’ (Odd likes that phrase.)
The field can only be reduced to zero (Odd likes to remind us that it wasn’t zero to begin with), and so
BLACK HOLES CAN’T BE MADE BY CLUMPING MATTER TOGETHER.

Got it?

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#727938 — 600 trillion Suns bright, 12.8 billion years old.

> black holes are inaccessible to observation and experiment.

"Black Hole" (J043947.08+163415.7) is the brightest object known to man;
600 trillion Suns bright, 12.8 billion years old.

    At their peak ( mere seconds ), Type Ia supernovae 
    are no brighter than 5 trillion Suns.

The Known Universe had less entropy then, 12.8 billion years ago,
hence the greater brightness.

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#727998 — Re: 600 trillion Suns bright, 12.8 billion years old.

On Monday, February 18, 2019 at 12:31:11 PM UTC-8, Jeff-Relf.Me wrote:
> > black holes are inaccessible to observation and experiment.
> 
> "Black Hole" (J043947.08+163415.7) is the brightest object known to man;
> 600 trillion Suns bright, 12.8 billion years old.

Sorry, but J043947.08+163415.7 is not a black hole, but a quasar... which may harbor a black hole... but a quasar itself is not a black hole...

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#728036 — 600 trillion Suns bright, 12.8 billion years old.

Paul Alsing replied:
> > > black holes are inaccessible to observation and experiment.
> > 
> > "Black Hole" (J043947.08+163415.7) is the brightest object known to man;
> > 600 trillion Suns bright, 12.8 billion years old.
> 
> Sorry, but J043947.08+163415.7 is not a black hole, but a quasar...
> which may harbor a black hole... but a quasar itself is not a black hole...

How bright would it be without a "Black Hole" of some sort ?

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#728058 — Re: 600 trillion Suns bright, 12.8 billion years old.

On 19/02/2019 06:23, Jeff-Relf.Me@. wrote:
> Paul Alsing replied:
>>>> black holes are inaccessible to observation and experiment.
>>>
>>> "Black Hole" (J043947.08+163415.7) is the brightest object known to man;
>>> 600 trillion Suns bright, 12.8 billion years old.
>>
>> Sorry, but J043947.08+163415.7 is not a black hole, but a quasar...
>> which may harbor a black hole... but a quasar itself is not a black hole...

Although the quasars light output is dominated by the black hole 
accretion disk with normal stars providing only a small fraction.
> 
> How bright would it be without a "Black Hole" of some sort ?

Accretion disks of black holes can convert something like 10-30% of the 
rest mass falling into it into electromagnetic radiation. Nuclear fusion 
is good for converting about 0.7% of available rest mass into energy.

So an active black hole would be more than an order of magnitude 
brighter after consuming a fixed quantity of fuel, and considerably more 
if you view the accretion disk face on or even more extreme if looking 
down onto the relativistically beamed polar outflows.

There will come a point even for black holes where radiation pressure 
will prevent further material falling onto the accretion disk so there 
will be some absolute limiting total brightness for a given mass BH.

-- 
Regards,
Martin Brown

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#728456 — 695 trillion suns, 12.5 billion years ago.

I wrote:
> > > "Black Hole" (J043947.08+163415.7) is the brightest object known to man;
> > > 600 trillion Suns bright, 12.8 billion years old.

Oops, I should've beeen looking at "Watts" (power), 
not (appearant) "brightness".

12.5 billion years ago, quasar J2157-3602 shown like 695 trillion suns;
in comparison, Type Ia supernovae shine no brighter than 5 trillion Suns.

The Known Universe had less entropy 12.5 billion years ago,
hence the greater luminosity/power/Watts.

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#728462 — 695 trillion suns, 12.5 billion years ago.

Oops, I wrote:
> 12.5 billion years ago, quasar J2157-3602 shown like 695 trillion suns;
> in comparison, Type Ia supernovae shine no brighter than 5 trillion Suns.

12.5 billion years ago, quasar J2157-3602 had the POWER of 695 trillion suns;
in comparison, the most luminous hypernovae (ASASSN-15lh) 
peaked at 572 billion suns.

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#727944

On Monday, February 18, 2019 at 5:31:34 AM UTC-10, sam.w...@gmail.com wrote:
> What exactly is a black hole?
> 
> "What is a black hole? In an article that has just appeared in the journal Nature Astronomy, LMU philosopher Erik Curiel shows that physicists use different definitions of the concept, depending on their own particular fields of interest.
> 
> "A black hole is conventionally thought of as an astronomical object that irrevocably consumes all matter and radiation which comes within its sphere of influence. Physically, a black hole is defined by the presence of a singularity, i.e., a region of space, bounded by an 'event horizon', within which the mass/energy density becomes infinite, and the normally well-behaved laws of physics no longer apply. However, as an article in the January issue of the journal Nature Astronomy demonstrates, a precise and agreed definition of this 'singular' state proves to be frustratingly elusive. Its author, Dr. Erik Curiel of the Munich Center for Mathematical Philosophy at LMU, summarizes the problem as follows: "The properties of black holes are the subject of investigations in a range of subdisciplines of physics – in optical physics, in quantum physics and of course in astrophysics. But each of these specialties approaches the problem with its own specific set of theoretical concepts."
> 
> "Erik Curiel studied philosophy as well as theoretical physics at Harvard University and the University of Chicago, and the primary aim of his current DFG-funded research project is to develop a precise philosophical description of certain puzzling aspects of modern physics. "Phenomena such as black holes belong to a realm that is inaccessible to observation and experiment. Work based on the assumption that black holes exist therefore involves a level of speculation that is unusual even for the field of theoretical physics." However, this difficulty is what makes the physical approach to the nature of black holes so interesting from the philosophical point of view. "The physical perspective on black holes is itself inextricably bound up with philosophical issues relating to ontological, metaphysical and methodological considerations," says Curiel."
> 
> 
> Read more at: https://phys.org/news/2019-02-black-hole.html#jCp

I calculated that the matter is 40 times as dense in a black hole
as is the proton density. Tightly packed protons and neutrons
are less dense than a black hole, when the proton radius is not 
changed. I use from .84fm to 1.2fm for r, the proton radius.
But its must be much smaller in a black hole, 6 times as 
small a radius as a proton in the Sun.

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#727958

On 2/18/2019 9:31 AM, sam.wormley@gmail.com wrote:
> What exactly is a black hole?
> 
> "What is a black hole? In an article that has just appeared in the journal Nature Astronomy, LMU philosopher Erik Curiel shows that physicists use different definitions of the concept, depending on their own particular fields of interest.
> 
> "A black hole is conventionally thought of as an astronomical object that irrevocably consumes all matter and radiation which comes within its sphere of influence. 

nope.  it is simply that the escape velocity is c.

Physically, a black hole is defined by the presence of a singularity,
i.e., a region of space, bounded by an 'event horizon', within which the
mass/energy density becomes infinite, and the normally well-behaved laws
of physics no longer apply.

nope. not infinite, one can weigh black holes by the orbiting stars
around it.

>However, as an article in the January issue of the journal Nature Astronomy demonstrates, a precise and agreed definition of this 'singular' state proves to be frustratingly elusive. Its author, Dr. Erik Curiel of the Munich Center for Mathematical Philosophy at LMU, summarizes the problem as follows: "The properties of black holes are the subject of investigations in a range of subdisciplines of physics – in optical physics, in quantum physics and of course in astrophysics. But each of these specialties approaches the problem with its own specific set of theoretical concepts."

> 
> "Erik Curiel studied philosophy as well as theoretical physics at Harvard University and the University of Chicago, and the primary aim of his current DFG-funded research project is to develop a precise philosophical description of certain puzzling aspects of modern physics. 

"philosphical" ?   so, it is more BS ?

>"Phenomena such as black holes belong to a realm that is inaccessible to observation and experiment. Work based on the assumption that black holes exist therefore involves a level of speculation that is unusual even for the field of theoretical physics." 

nope, escape velocity is c.   not unusual, follows simple math.

>However, this difficulty is what makes the physical approach to the nature of black holes so interesting from the philosophical point of view. "The physical perspective on black holes is itself inextricably bound up with philosophical issues relating to ontological, metaphysical and methodological considerations," says Curiel."


BULLSHIT ALARM !!

"ontological, metaphysical and methodological considerations"

cut that guys funding off now!

> 
> 
> Read more at: https://phys.org/news/2019-02-black-hole.html#jCp
> 

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#727963

Light has never obeyed the escape velocity law... only the atom...
By the constancy of light speed its leaving gravity will not slow down.
No amount of gravity can capture light. A light bubble can always
get out.

God creates gravity.

Mitchell Raemsch

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#727966

On 2/18/2019 3:58 PM, mitchrae3323@gmail.com wrote:
> Light has never obeyed the escape velocity law... 


electricity escapes from batterys to make light in light bulbs...

> only the atom...

pixels are atoms of the screen

> By the constancy of light speed its leaving gravity will not slow down.
> No amount of gravity can capture light. A light bubble can always
> get out.

Underwater air bubbles escape from Water gravity

> 
> God creates gravity.
> 
> Mitchell Raemsch
> 

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#728123

On Monday, February 18, 2019 at 2:17:47 PM UTC-8, Serg Io wrote:
> On 2/18/2019 3:58 PM, mitchrae3323@gmail.com wrote:
> > Light has never obeyed the escape velocity law... 
> 
> 
> electricity escapes from batterys to make light in light bulbs...
> 
> > only the atom...
> 
> pixels are atoms of the screen
> 
> > By the constancy of light speed its leaving gravity will not slow down.
> > No amount of gravity can capture light. A light bubble can always
> > get out.
> 
> Underwater air bubbles escape from Water gravity
> 
> > 
> > God creates gravity.
> > 
> > Mitchell Raemsch
> >

Gravity cannot overcome light's constant speed.
It can always escape any amount of gravity.
God creates gravity.

Mitchell Raemsch

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#728170

On 2/19/2019 3:17 PM, mitchrae3323@gmail.com wrote:
> On Monday, February 18, 2019 at 2:17:47 PM UTC-8, Serg Io wrote:
>> On 2/18/2019 3:58 PM, mitchrae3323@gmail.com wrote:
>>> Light has never obeyed the escape velocity law... 
>>
>>
>> electricity escapes from batterys to make light in light bulbs...
>>
>>> only the atom...
>>
>> pixels are atoms of the screen
>>
>>> By the constancy of light speed its leaving gravity will not slow down.
>>> No amount of gravity can capture light. A light bubble can always
>>> get out.
>>
>> Underwater air bubbles escape from Water gravity
>>
>>>
>>> God creates gravity.
>>>
>>> Mitchell Raemsch
>>>
> 
> Gravity cannot overcome light's constant speed.
> It can always escape any amount of gravity.
> God creates gravity.
> 
> Mitchell Raemsch
> 

bubbles in water escape gravity, at slow speed.

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#727991

On 2/18/2019 4:40 PM, Serg Io wrote:
> On 2/18/2019 9:31 AM, sam.wormley@gmail.com wrote:
>> What exactly is a black hole?
>>
>> "What is a black hole? In an article that has just appeared in the journal Nature Astronomy, LMU philosopher Erik Curiel shows that physicists use different definitions of the concept, depending on their own particular fields of interest.
>>
>> "A black hole is conventionally thought of as an astronomical object that irrevocably consumes all matter and radiation which comes within its sphere of influence.
> 
> nope.  it is simply that the escape velocity is c.
> 
> Physically, a black hole is defined by the presence of a singularity,
> i.e., a region of space, bounded by an 'event horizon', within which the
> mass/energy density becomes infinite, and the normally well-behaved laws
> of physics no longer apply.
> 
> nope. not infinite, one can weigh black holes by the orbiting stars
> around it.
> 
>> However, as an article in the January issue of the journal Nature Astronomy demonstrates, a precise and agreed definition of this 'singular' state proves to be frustratingly elusive. Its author, Dr. Erik Curiel of the Munich Center for Mathematical Philosophy at LMU, summarizes the problem as follows: "The properties of black holes are the subject of investigations in a range of subdisciplines of physics – in optical physics, in quantum physics and of course in astrophysics. But each of these specialties approaches the problem with its own specific set of theoretical concepts."
> 
>>
>> "Erik Curiel studied philosophy as well as theoretical physics at Harvard University and the University of Chicago, and the primary aim of his current DFG-funded research project is to develop a precise philosophical description of certain puzzling aspects of modern physics.
> 
> "philosphical" ?   so, it is more BS ?
> 
>> "Phenomena such as black holes belong to a realm that is inaccessible to observation and experiment. Work based on the assumption that black holes exist therefore involves a level of speculation that is unusual even for the field of theoretical physics."
> 
> nope, escape velocity is c.   not unusual, follows simple math.
> 
>> However, this difficulty is what makes the physical approach to the nature of black holes so interesting from the philosophical point of view. "The physical perspective on black holes is itself inextricably bound up with philosophical issues relating to ontological, metaphysical and methodological considerations," says Curiel."
> 
> 
> BULLSHIT ALARM !!
> 
> "ontological, metaphysical and methodological considerations"
> 
> cut that guys funding off now!
> 
>>
>>
>> Read more at: https://phys.org/news/2019-02-black-hole.html#jCp
>>
> 
Warmley Tries to do physics again and gets owned by Sergio!
No surprise there.

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#728001

On Monday, February 18, 2019 at 1:40:58 PM UTC-8, Serg Io wrote:
> On 2/18/2019 9:31 AM, sam.wormley@gmail.com wrote:
> > What exactly is a black hole?
> > 
> > "What is a black hole? In an article that has just appeared in the journal Nature Astronomy, LMU philosopher Erik Curiel shows that physicists use different definitions of the concept, depending on their own particular fields of interest.
> > 
> > "A black hole is conventionally thought of as an astronomical object that irrevocably consumes all matter and radiation which comes within its sphere of influence. 
> 
> nope.  it is simply that the escape velocity is c.
> 
> Physically, a black hole is defined by the presence of a singularity,
> i.e., a region of space, bounded by an 'event horizon', within which the
> mass/energy density becomes infinite, and the normally well-behaved laws
> of physics no longer apply.
> 
> nope. not infinite, one can weigh black holes by the orbiting stars
> around it.

Sergio, infinite density is not the same thing as infinite mass. If you take any mass, one pound, for example, and compress it to zero volume, the math tells you that is has infinite density... but it still weighs just one pound... so yes, we sure can deduce the mass of a black hole from the stars orbiting them, and this is done all the time.

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#728029

On 2/18/2019 8:09 PM, pnalsing@gmail.com wrote:
> On Monday, February 18, 2019 at 1:40:58 PM UTC-8, Serg Io wrote:
>> On 2/18/2019 9:31 AM, sam.wormley@gmail.com wrote:
>>> What exactly is a black hole?
>>>
>>> "What is a black hole? In an article that has just appeared in the journal Nature Astronomy, LMU philosopher Erik Curiel shows that physicists use different definitions of the concept, depending on their own particular fields of interest.
>>>
>>> "A black hole is conventionally thought of as an astronomical object that irrevocably consumes all matter and radiation which comes within its sphere of influence. 
>>
>> nope.  it is simply that the escape velocity is c.
>>
>> Physically, a black hole is defined by the presence of a singularity,
>> i.e., a region of space, bounded by an 'event horizon', within which the
>> mass/energy density becomes infinite, and the normally well-behaved laws
>> of physics no longer apply.
>>
>> nope. not infinite, one can weigh black holes by the orbiting stars
>> around it.
> 
> Sergio, infinite density is not the same thing as infinite mass. If you take any mass, one pound, for example, and compress it to zero volume, the math tells you that is has infinite density... but it still weighs just one pound... so yes, we sure can deduce the mass of a black hole from the stars orbiting them, and this is done all the time.
> 

I think all the mass inside a black hole is assigned to a single point
at the center.

I think he is calling the entire black hole a singularity, which is not
correct, but I think just the center is. and WIKI says;

https://en.wikipedia.org/wiki/Gravitational_singularity

"Gravitational singularities are mainly considered within general
relativity, where density apparently becomes infinite at the center of a
black hole"

"a Kerr black hole, the singularity occurs on a ring (a circular line),
known as a "ring singularity". Such a singularity may also theoretically
become a wormhole.[10]"

I can't visualize this stuff,

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#728032

On Monday, February 18, 2019 at 9:11:25 PM UTC-8, Serg Io wrote:
> On 2/18/2019 8:09 PM, pnal...@gmail.com wrote:
> > On Monday, February 18, 2019 at 1:40:58 PM UTC-8, Serg Io wrote:
> >> On 2/18/2019 9:31 AM, sam.wormley@gmail.com wrote:
> >>> What exactly is a black hole?
> >>>
> >>> "What is a black hole? In an article that has just appeared in the journal Nature Astronomy, LMU philosopher Erik Curiel shows that physicists use different definitions of the concept, depending on their own particular fields of interest.
> >>>
> >>> "A black hole is conventionally thought of as an astronomical object that irrevocably consumes all matter and radiation which comes within its sphere of influence. 
> >>
> >> nope.  it is simply that the escape velocity is c.
> >>
> >> Physically, a black hole is defined by the presence of a singularity,
> >> i.e., a region of space, bounded by an 'event horizon', within which the
> >> mass/energy density becomes infinite, and the normally well-behaved laws
> >> of physics no longer apply.
> >>
> >> nope. not infinite, one can weigh black holes by the orbiting stars
> >> around it.
> > 
> > Sergio, infinite density is not the same thing as infinite mass. If you take any mass, one pound, for example, and compress it to zero volume, the math tells you that is has infinite density... but it still weighs just one pound... so yes, we sure can deduce the mass of a black hole from the stars orbiting them, and this is done all the time.
> > 
> 
> I think all the mass inside a black hole is assigned to a single point
> at the center.

Yes, mathematically this is the model...

> I think he is calling the entire black hole a singularity, which is not
> correct, but I think just the center is. and WIKI says;
> 
> https://en.wikipedia.org/wiki/Gravitational_singularity
> 
> "Gravitational singularities are mainly considered within general
> relativity, where density apparently becomes infinite at the center of a
> black hole"
> 
> "a Kerr black hole, the singularity occurs on a ring (a circular line),
> known as a "ring singularity". Such a singularity may also theoretically
> become a wormhole.[10]"

... with much emphasis on the "theoretically" part...

> I can't visualize this stuff,

I don't think that you are alone, I'm pretty sure that not many people can visualize this, and I can't either.

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#728039

On 2/18/2019 9:11 PM, Serg Io wrote:
> On 2/18/2019 8:09 PM, pnalsing@gmail.com wrote:
>> On Monday, February 18, 2019 at 1:40:58 PM UTC-8, Serg Io wrote:
>>> On 2/18/2019 9:31 AM, sam.wormley@gmail.com wrote:
>>>> What exactly is a black hole?
>>>>
>>>> "What is a black hole? In an article that has just appeared in the journal Nature Astronomy, LMU philosopher Erik Curiel shows that physicists use different definitions of the concept, depending on their own particular fields of interest.
>>>>
>>>> "A black hole is conventionally thought of as an astronomical object that irrevocably consumes all matter and radiation which comes within its sphere of influence.
>>>
>>> nope.  it is simply that the escape velocity is c.
>>>
>>> Physically, a black hole is defined by the presence of a singularity,
>>> i.e., a region of space, bounded by an 'event horizon', within which the
>>> mass/energy density becomes infinite, and the normally well-behaved laws
>>> of physics no longer apply.
>>>
>>> nope. not infinite, one can weigh black holes by the orbiting stars
>>> around it.
>>
>> Sergio, infinite density is not the same thing as infinite mass. If you take any mass, one pound, for example, and compress it to zero volume, the math tells you that is has infinite density... but it still weighs just one pound... so yes, we sure can deduce the mass of a black hole from the stars orbiting them, and this is done all the time.
>>
> 
> I think all the mass inside a black hole is assigned to a single point
> at the center.
> 
> I think he is calling the entire black hole a singularity, which is not
> correct, but I think just the center is. and WIKI says;
> 
> https://en.wikipedia.org/wiki/Gravitational_singularity
> 
> "Gravitational singularities are mainly considered within general
> relativity, where density apparently becomes infinite at the center of a
> black hole"
> 
> "a Kerr black hole, the singularity occurs on a ring (a circular line),
> known as a "ring singularity". Such a singularity may also theoretically
> become a wormhole.[10]"
> 
> I can't visualize this stuff,
> 

Total Fantasy Land, sorry:

Think of a single pixel as holding infinite information. Like zooming in 
on a single pixel in an escape time fractal. Well, that one little pixel 
is huge! Infinite, in a sense. It holds infinite data, wrt some 
mathematical models:

https://youtu.be/8cgp2WNNKmQ

Think of the Mandelbrot set itself being contained in a _single_ pixel, 
if we zoom out far enough, this is the case. Fwiw, this helps me think 
of infinite density...

Data gets encrypted into a fractal when it enters a black hole. Sorry 
for going to crazy town...

Well, we can store data in the roots of complex numbers that comprise a 
lot of fractals, actually really works:

https://groups.google.com/d/topic/comp.lang.c++/bB1wA4wvoFc/discussion

(z-c)^(1/n) has Julia roots for the set c that can store real data. Each 
object of information, like a message, gets encrypted into the fractal 
itself, and creates a unique, beautiful rendering. Data is n-ary, wrt a 
symbol table. The nice part is that the data can be loaded back up and 
recovered fully intact. There is no data loss. BH might have infinite 
precision... ? ;^O

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#728139

On Monday, February 18, 2019 at 7:31:34 AM UTC-8, sam.w...@gmail.com wrote:
> What exactly is a black hole?
> 
> "What is a black hole? In an article that has just appeared in the journal Nature Astronomy, LMU philosopher Erik Curiel shows that physicists use different definitions of the concept, depending on their own particular fields of interest.
> 
> "A black hole is conventionally thought of as an astronomical object that irrevocably consumes all matter and radiation which comes within its sphere of influence. Physically, a black hole is defined by the presence of a singularity, i.e., a region of space, bounded by an 'event horizon', within which the mass/energy density becomes infinite, and the normally well-behaved laws of physics no longer apply. However, as an article in the January issue of the journal Nature Astronomy demonstrates, a precise and agreed definition of this 'singular' state proves to be frustratingly elusive. Its author, Dr. Erik Curiel of the Munich Center for Mathematical Philosophy at LMU, summarizes the problem as follows: "The properties of black holes are the subject of investigations in a range of subdisciplines of physics – in optical physics, in quantum physics and of course in astrophysics. But each of these specialties approaches the problem with its own specific set of theoretical concepts."
> 
> "Erik Curiel studied philosophy as well as theoretical physics at Harvard University and the University of Chicago, and the primary aim of his current DFG-funded research project is to develop a precise philosophical description of certain puzzling aspects of modern physics. "Phenomena such as black holes belong to a realm that is inaccessible to observation and experiment. Work based on the assumption that black holes exist therefore involves a level of speculation that is unusual even for the field of theoretical physics." However, this difficulty is what makes the physical approach to the nature of black holes so interesting from the philosophical point of view. "The physical perspective on black holes is itself inextricably bound up with philosophical issues relating to ontological, metaphysical and methodological considerations," says Curiel."
> 
> 
> Read more at: https://phys.org/news/2019-02-black-hole.html#jCp


A galactic black hole could be a region where stars are close enough together that the total gravity is too great for light to escape.  It does not follow that there need be a singularity there.

Double-A

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