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Kowalski
How exactly is the amount of Hawking radiation emitted by a black hole related to it's mass/Schwarzschild radius/etc? Is there a formula relating the two for instance?

(I'm trying to calculate the time it would take for one of the LHC black holes that will supposedly destroy the Earth - ad nauseum - to dissipate...)

Thanks
Grumpy
Kowalski

Since the gravitational flux density of a BH is, by definition, near infinite, but the area of the event horizon varies as the cube of the radius I would assume that the larger the BH(and thus EH radius), the smaller the mass of the Hawking radiation(as expressed as the percentage of total BH weight). Also, very small BHs(as would be produced by the LHC) would have Quantum effects to deal with. Theory suggests that the smaller the BH, the faster it would evaporate, with the smallest going out in a flash of radiation as soon as they formed. Time will tell.

Grumpy cool.gif
rpenner
There are a number of problems with your post Grumpy.

If you want to know about Hawking Radiation you could look up Hawking radiation on Wikipedia and get exact formulas and calculations with only a thin taste of the physics underlying these formula.

Long story short: Black holes of a thousand tons or less are speedy mass-to-energy conversion bombs. They radiate too much of their mass away to be moved from place-to-place or eat.

Very very tiny black holes blow up even sooner, but since they never massed much, the energy doesn't amount to much.

Billion-ton black holes are long-lived and might (through Bondi accretion) eat a planet. How long it would take depends on the mass of the black hole, but for a billion-mass black hole it would take over 47 million years to slurp the Earth through what is effectively a narrow straw.

http://en.wikipedia.org/wiki/Hawking_radiation
http://arxiv.org/abs/0806.3381
Grumpy
rpenner

As I said, very small BHs, high radiation in relation to mass, flash of radiation. Large holes, less radiation as a percent of mass, thus longer lives.

Grumpy cool.gif
RobDegraves
Kowalski

You also have to get a feel for how small a micro black hole produced by the LHC would be.

(BTW... RPenner, do feel free to correct me if I am wrong)

A micro black hole could only be produced if one proton collides with another proton with enough force.... and if the theory on Large Extra Dimensions is correct. This theory is needed because gravity is too weak at those sizes to be a factor normally.

A good way to get a feel for this is to think of a normal black hole. A normal black hole would crush the Earth into about the size of a marble. If the Sun were a black hole it would be 3 km across as opposed to it's current 1,390,000 km across. Now.. this is the size of the event horizon, not the actual size of the black hole itself, which would be much smaller... if not infinitely so.

Now.. let's take a micro black hole. If it starts off as two protons, how small do you think the event horizon would be? It would be so small as to be near the Planck length... so small it's barely imaginable, though you could calculate it.

It would still have the same mass as two protons, not more. Therefore it's gravity would barely be a factor in accumulating mass... at that is without even factoring in Hawking Radiation which is generally accepted and would see the micro black hole evaporate nigh instantly.... maybe faster. This was explained above... the smaller the black hole, the faster it evaporates. At the size it would be after being created from two protons, it would evaporate so fast that it could never interact with anything first.

The only way that it could accumulate matter would be if it had a charge (again this would be only if it didn't evaporate first). However, if micro black holes could be created with a charge by colliding protons and didn't evaporate, we would already be in one. Cosmic rays collide protons on protons at energies far past the LHC and if they produced charged micro black holes we would be awash in them, since cosmic rays are going through you right now at the rate of thousands per second.

I have been through this argument a lot. There are a lot of people who are using the general public's lack of knowledge of the physics involved to sow fear for their own purposes.
Harry Costas
G'day from the land of ozzzzzzz

You may find this topic interesting

http://arxiv.org/abs/astro-ph/9212005
The Escape of Gravitational Radiation from the Field of Massive Bodies

Authors: Richard H. Price, Jorge Pullin, Prasun Kundu
(Submitted on 23 Dec 1992)

QUOTE
Abstract: We consider a compact source of gravitational waves of frequency $\omega$, in or near a massive spherically symmetric distribution of matter or a black hole. Recent calculations have led to apparently contradictory results for the influence of the massive body on the propagation of the waves. We show here that the results are in fact consistent and in agreement with the ``standard'' viewpoint in which the high frequency compact source produces the radiation as if in a flat background, and the background curvature affects the propagation of these waves.


Hawking cracks black hole paradox
14/07/2004 19:00
http://www.newscientist.com/article.ns?id=dn6151


Quote:
After nearly 30 years of arguing that a black hole destroys everything that falls into it, Stephen Hawking is saying he was wrong. It seems that black holes may after all allow information within them to escape. Hawking will present his latest finding at a conference in Ireland next week.

Hawking concedes black hole bet
21/07/2004 19:26
http://www.newscientist.com/article/...-hole-bet.html

Black holes turned 'inside out'
http://news.bbc.co.uk/1/hi/sci/tech/3913145.stm

Quote:
Stephen Hawking has put forward a new theory that changes the way scientists view black holes, saying he was wrong about them in the past.


Stephen Hawking, Black
Holes And Alex Collier
http://www.rense.com/general54/zlecx.htm


QUOTE (->
QUOTE
Abstract: We consider a compact source of gravitational waves of frequency $\omega$, in or near a massive spherically symmetric distribution of matter or a black hole. Recent calculations have led to apparently contradictory results for the influence of the massive body on the propagation of the waves. We show here that the results are in fact consistent and in agreement with the ``standard'' viewpoint in which the high frequency compact source produces the radiation as if in a flat background, and the background curvature affects the propagation of these waves.


Hawking cracks black hole paradox
14/07/2004 19:00
http://www.newscientist.com/article.ns?id=dn6151


Quote:
After nearly 30 years of arguing that a black hole destroys everything that falls into it, Stephen Hawking is saying he was wrong. It seems that black holes may after all allow information within them to escape. Hawking will present his latest finding at a conference in Ireland next week.

Hawking concedes black hole bet
21/07/2004 19:26
http://www.newscientist.com/article/...-hole-bet.html

Black holes turned 'inside out'
http://news.bbc.co.uk/1/hi/sci/tech/3913145.stm

Quote:
Stephen Hawking has put forward a new theory that changes the way scientists view black holes, saying he was wrong about them in the past.


Stephen Hawking, Black
Holes And Alex Collier
http://www.rense.com/general54/zlecx.htm


In his lecture he says that the Andromedans told him that: "Everything in our universe, including us, came from a black hole."



Hawking Loses Bet; Changes Mind on Black Holes
http://www.space.com/news/hawking_bet_040716.html


QUOTE
"I've been thinking about this problem for the last 30 years, and I think I now have the answer to it," Hawking told the British Broadcasting Corp.'s "Newsnight" program.

"A black hole only appears to form but later opens up and releases information about what fell inside. So we can be sure of the past and predict the future."



RobDegraves
I certainly hope you intended that as a joke.

These guys are nuts.

Saying that Stephen Hawkings proves that Alex Collier is right is like saying that because monkeys go "OOk OOk" that proves that we evolved from reptiles.

Oh.. wait..

You guys are saying that.. or at least something equally as absurd.
Harry Costas
G'day Rob


Whats your point?

It's not what we say but! What Hawking says.


RobDegraves
Hmmm... no.. it's not what Hawking says.. it's the fact that you misinterpret what he says to try to and use it as evidence for something obviously retarded.

Stephen Hawking is saying that the information paradox can be solved. This does have implications for physics but has nothing to do with what you are trying to talk about.

Saying that Hawking's solution proves that aliens came out of a Black Hole is like saying you can put a cow in a blender and pull out a kitten.

To say that Collier is either a con or insane is easily a truism

Which one are you?
Harry Costas
G'day Rob

In other words you think that nothing can escape a black hole.

THan please define a black hole and its properties.
RobDegraves
Hmmm...

First of all... don't say "in other words" if you don't understand what I said.

Secondly, this has nothing to do with whether I think energy can escape a Black Hole. You still can't pull out aliens from the fifth dimension out of what Hawking has to say.

Listen... if you are really stupid enough to believe this con job...

Either you need psychological help yourself... or you aren't smart enough to argue with in the first place. Seriously... I try to be polite but this is ridiculous stuff. Aliens from Andromeda? Lizard people that are corrupting us? The Tooth Fairy is at least a reasonable myth.
Harry Costas
G'day Rob


What if?

Is it worth knowing the information?

Please do not think for one sec, that what I'm saying comes from a rice bubble pack.

To understand compact matter is the key to it all.

AlphaNumeric
http://en.wikipedia.org/wiki/Hawking_radia...ole_evaporation Look at the expression for P.
Grumpy
Harry Costas

QUOTE
Stephen Hawking, Black
Holes And Alex Collier
http://www.rense.com/general54/zlecx.htm


You are such a nimrod, you believe everything you read without the filter of any reasoning ability.

All Hawking was talking about was information about what had been eaten in the past by a BH is preserved. He is not saying any MATTER can leave an event horizon, just INFORMATION about that matter.

Just what stupid garbage are you going to post next time???

Grumpy cool.gif
philip347
These answers are all wrong, as Hawking Radation, is realted in part to materials taken in by any black hole.
RobDegraves
Would you care to explain Phillip?
rpenner
QUOTE (Grumpy+Jun 4 2009, 01:37 PM)
the area of the event horizon varies as the cube of the radius

This is what I spotted, Grumpy. I disagree.
philip347
The process of the formation of black holes are leftover aspects of usually stars that have undergone the process of collapse.

This mathematically give the dimension of one, to the baseline equation, as the density of the black hole, is that it is such that only a next to next leftover of atomic structures is present.

So this is indefinite mass, over normal space-time as a solid state factor.

The core density is of little matter at this point, however what is of important, are the magnetic fields, however they may express themselves, which is relational to time space.

So therefore, what one is looking for, are magnetic lines of representation as enacted from the core density itself.

The computer modeling is available for this stement to act as a working movement drawing in the CAD CAM visual drawing arena.

>You now have two probable in function set theories.

A. Would be the locus of the primary virgin black hole, that is probably by itself, however does or might not take in any matter, other than stellar dust.

The yield off of Hawking Radiation from example A. would be, what is the slighter expression of matter which is taken into the magnetic envelope of a black hole, then taken apart? Two as a subset function, where is this expression of matter exhausted?

The answer as in probability as most black hole center densities are round, would be an analiation expression of Hawking Radiation, at the near poles.

This fact was observed a while back by the Hawking investigative group, as a radiation expression of glow, near the relative poles north and south of a black hole.

TWO,B The second example would not be a non virgin black hole, that would be placed in an area of time space to where an average amount of leftover matter is observed being taken into the magnetic fields, of a black hole.

As said in published theory, these magnetic force lines generated by the singularity density are so intense, that these lines of force rip down the basic structure of the atoms of most matter.

So since time space is a multi fielded reality, with many differing dimensions to it, the take in matter that is taken into the event horizon or other parts of the take in spacts of the black hole, must be expressed as with reference to the universal law of energy conservation.

This factor would mean, on the non virgin black hole, that a ring as expressed near the north and south poles of most black holes, would express the dimensionalities of the taken in and ripped apart matter.

So therefore what Hawking Radiation is, is it seems a similar to microwavic generational forces, as expressed as to display, by more than dualist representation of changed taken in by black hole matter.

Sources, mechanics of the Hawking primary investigative group, as published by physicist writer, Marcia Bartsuiack
philip347
Notes on post: Nobody is absolutely sure that all black hole densities are round?

The magnetic lines of expression around a black hole, are expressed as force lines held in a field.

There must be a tidal rip, which catches most matter within that filed, then tears at this matter.

A near virgin black holes is possible for a mathematical expression of x or said value amount of time.
Harry Costas
G'day from the land of ozzz

Phillip I think you are on track.

To understand the properties of black holes one may need to read up on Nuclear transition phases.

These are general research via arXiv, you can also to a search via NASA\ADS

Nuclear transition phase cosmology
http://arxiv.org/find/all/1/all:+AND+cosmo...e/0/1/0/all/0/1


Nuclear transition phase
http://arxiv.org/find/all/1/all:+AND+trans...e/0/1/0/all/0/1

By understanding transition phase we can understand the properties of what makes up the so called black holes.

Vector fields can prevent EMR from escaping.

But!

To have a spherical BH it is not possible, due to the quantum that makes up the BH.

Electromagnetic waves would create a vortex that is able to form a jet formation that gravity radiation can excape and carry with it quantum particles close to the speed of light. We notice these properties in jets from Jets large and small. Their stability is more comon from large active galactic nuclei from ultra large compact matter that some call black holes.
RobDegraves
Wow...

That was an unusually long series of babbling nonsense.

Seriously... has either of you ever considered actually taking a few courses on this stuff... or is it easier to make it up as you go?
Harry Costas
G'day Rob

Why not give us you scientific opinion on the matter rather than an emotional hangup.


Grumpy
rpenner

Sphere Surface Area = 4 • Pi • r² = Pi • d²

You are right, my bad.



Harry Costas

QUOTE
Electromagnetic waves would create a vortex that is able to form a jet formation that gravity radiation can excape and carry with it quantum particles close to the speed of light. We notice these properties in jets from Jets large and small. Their stability is more comon from large active galactic nuclei from ultra large compact matter that some call black holes.


Nothing can escape THE EVENT HORIZON. It does not matter one whit what is happening within the EH to the matter making up the BH. Jets are a phenomina of the ACCRETION DISK and it's magnetic field, powered by the BH's gravity. They are ELECTROMAGNETIC in nature, not gravity "radiation".

Grumpy cool.gif
Harry Costas
G'day from the land of ozzzzzzz

There is this notion that some scientists think that nothing can escape a so called black hole.

They have taken this to heart without knowing the properties of compact matter.

This notion has trapped some scientists in not researching further the actual formation of super jet formation that is able to remain stable for millions of years.

We live now in the modern ERA.

http://arxiv.org/abs/0902.1569
Are black holes in alternative theories serious astrophysical candidates? The case for Einstein-Dilaton-Gauss-Bonnet black holes

Authors: Paolo Pani, Vitor Cardoso
(Submitted on 10 Feb 2009 (v1), last revised 21 Apr 2009 (this version, v3))

QUOTE
Abstract: It is generally accepted that Einstein's theory will get some as yet unknown corrections, possibly large in the strong field regime. An ideal place to look for these modifications is around the vicinities of compact objects such as black holes. Our case study here are Dilatonic Black Holes, which arise in the framework of Gauss-Bonnet couplings and one-loop corrected four-dimensional effective theory of heterotic superstrings at low energies. These are interesting objects as a prototype for alternative, yet well-behaved gravity theories: they evade the "no-hair" theorem of General Relativity but were proved to be stable against radial perturbations. We investigate the viability of these black holes as astrophysical objects and try to provide some means to distinguish them from black holes in General Relativity. We start by extending previous works and establishing the stability of these black holes against axial perturbations. We then look for solutions of the field equations describing slowly rotating black holes and study geodesic motion around this geometry. Depending on the values of mass, dilaton charge and angular momentum of the solution, one can have measurable differences in the ISCO location and orbital frequency, relatively to black holes in General Relativity. Such differences may be useful in future experiments, to discriminate between alternative theories of gravity.



and

http://arxiv.org/abs/0809.3850
Black holes and black hole thermodynamics without event horizons

Authors: Alex B. Nielsen
(Submitted on 23 Sep 2008)

QUOTE (->
QUOTE
Abstract: It is generally accepted that Einstein's theory will get some as yet unknown corrections, possibly large in the strong field regime. An ideal place to look for these modifications is around the vicinities of compact objects such as black holes. Our case study here are Dilatonic Black Holes, which arise in the framework of Gauss-Bonnet couplings and one-loop corrected four-dimensional effective theory of heterotic superstrings at low energies. These are interesting objects as a prototype for alternative, yet well-behaved gravity theories: they evade the "no-hair" theorem of General Relativity but were proved to be stable against radial perturbations. We investigate the viability of these black holes as astrophysical objects and try to provide some means to distinguish them from black holes in General Relativity. We start by extending previous works and establishing the stability of these black holes against axial perturbations. We then look for solutions of the field equations describing slowly rotating black holes and study geodesic motion around this geometry. Depending on the values of mass, dilaton charge and angular momentum of the solution, one can have measurable differences in the ISCO location and orbital frequency, relatively to black holes in General Relativity. Such differences may be useful in future experiments, to discriminate between alternative theories of gravity.



and

http://arxiv.org/abs/0809.3850
Black holes and black hole thermodynamics without event horizons

Authors: Alex B. Nielsen
(Submitted on 23 Sep 2008)

Abstract: We investigate whether black holes can be defined without using event horizons. In particular we focus on the thermodynamic properties of event horizons and the alternative, locally defined horizons. We discuss the assumptions and limitations of the proofs of the zeroth, first and second laws of black hole mechanics for both event horizons and trapping horizons. This leads to the possibility that black holes may be more usefully defined in terms of trapping horizons. We also show how Hawking radiation can also be seen to arise from trapping horizons and discuss which horizon area should be associated with the gravitational entropy.



RobDegraves
QUOTE
This notion has trapped some scientists in not researching further the actual formation of super jet formation that is able to remain stable for millions of years.


Do you have any research on these jets other than UFO abductees?

Just curious.
Harry Costas
G'day from the land of ozzzzzzzz

Hello Rob
The research on jets their formation and properties is general information and can be found just by Google, or arXiv or NASA/ADS.

Grumpy
Harry Costas

Event Horizon=radius from a BH where escape velocity exceeds lightspeed.

Nothing with mass can exceed light speed.

Therefore nothing with mass can escape a BH.

It's really pretty simple.

Grumpy cool.gif
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