Can White Holes and Hawking Radiation Explain the Big Bang?

[UrbanXrisis]

I read this about a white hole and had some thoughts:

"The short answer is that a white hole is something which probably cannot exist in the real universe. A white hole will turn up in your mathematics if you explore the space-time around a black hole without including the star which made the black hole (ie. there is absolutely no matter in the solution). Once you add any matter to the space-time, the part which included a white hole disappears."

Here's thougts, before the big band, there was nothing. Since there is no mass, this gives rise to a white hole. The white hole, or anti-black hole, spits out matter producing the big bang.

any thoughts?

 

[Mk]

lol, my mind is just like... yeah.

 

[scilover89]

From what astrologists know, particles were created after Big Bang from energy.
For more information, read The Brief History of Time from Stephen Hawking.

 

[Garth]

From what astrologists know, particles were created after Big Bang from energy.
For more information, read The Brief History of Time from Stephen Hawking.

Is Stephen Hawking an astrologist? What star sign is he?

I actually like the idea of a

Big Band

- ever since Glen Miller!

To be serious, the idea that the Big Bang might be a "white hole" has some credability although it has to be treated with caution. The Schwarzschild solution of Einstein's GR field equation is a local spherically symmetric solution, the Big Bang comes from the cosmological, homogeneous and isotropic solution. They are not the same. A quantum gravity might indeed lead to a "bounce" at the singularities in both but that would be "shooting in the dark" at the moment, so be cautious.

Garth

 

[UrbanXrisis]

Thanks for the responce Garth, can you explain what you mean in less scientific words? I'm very interested in this topic but I don't think I know everything about "Schwarzschild solution" or what you mean by "cosmological, homogeneous and isotropic solution."

Thanks

 

[Garth]

The theory of General Relativity really is Einstein's field equation. This applies at every event in the universe and links the second derivatives of the way spacetime curves to the distribution of density, energy and stresses at those events. To make any sense of it you have to solve it, i.e. integrate the tensors twice and apply suitable boundary conditions.

There are only two relatively straight forward cases.

The first is that in which the only mass you consider is spherically symmetric and static, the density is a function of radius only, such as a mass like the Earth or the Sun; this is the Schwarzschild solution.

The other case is when the density is smeared out into a representative gas of the same density, temperature and pressure throughout the entire universe, density is a function of time only. This is the cosmological case and depends on the two assumptions that the universe is isotropic (it looks the same in all directions) and homogeneous (it is the same at all positions at any particular epoch).

The first solution is used in the local tests of the theory and the second solution has been used in all cosmology for the last seventy years or so.

Garth

 

[UrbanXrisis]

How does what you say tie into what I said?

so be cautious

how come?

 

[Garth]

I understood your orignal suggestion to be that the Big Bang was in effect a 'white hole' in a 'nothingness'. I was just pointing out that as the black hole solution was a local phenomena embeded in a cosmological background, you could not automatically apply the white hole equivalent, which is a very speculative concept in the first place, to the universe as a whole. They are two separate and different solutions to the GR field equation. You have to be very cautious about such extrapolations.

Garth.

 

[cosmoboy]

white hole

There is an interesting link about the white holes

http://casa.colorado.edu/~ajsh/schww.html

 

[UrbanXrisis]

There is an interesting link about the white holes

http://casa.colorado.edu/~ajsh/schww.html

thanks, I read about that already :)

I understood your orignal suggestion to be that the Big Bang was in effect a 'white hole' in a 'nothingness'. I was just pointing out that as the black hole solution was a local phenomena embeded in a cosmological background, you could not automatically apply the white hole equivalent, which is a very speculative concept in the first place, to the universe as a whole. They are two separate and different solutions to the GR field equation. You have to be very cautious about such extrapolations.

Garth.

Garth, I still have trouble understanding what you are saying. I'm very sorry but I an not very knowledgeble in this field. Especially "black hole solution was a local phenomena embeded in a cosmological background." Are you saying that there has to be "space" for a black hole to exist, and since there is no space for a black hole to exist, there can't be any white holes?

 

[Garth]

UrbanXrisis,
Sorry if I have not made myself clear.
The theory of GR is based on some very profound and rather simple principles. The model of a rubber sheet with a bowling ball making a bent in the middle is a good way to think about how mass makes space-time 'curve'. However to solve GR’s field equation for a particular situation leads to some very difficult and complicated equations - grad school stuff.

One of these situations is the solution for the gravitational field around a spherical mass such as the Sun. This is called the Schwarzschild solution. It leads to the understanding that if the gravitational field is strong enough then even light would not be able to escape from a boundary around the mass and so it would form a ‘black’ object. Furthermore inside this boundary, called the event horizon, the crushing gravitational force could become so great that no force is known that could withstand it. Therefore the massive object would contract down under its own gravitational field and keep going, because there is nothing to stop it, until it became a singularity at the centre, something with zero volume and infinite density. Therefore this object is known as a Black Hole

But if the object forming a black hole was rotating then the singularity at the centre becomes not a point but a ring, an annulus. And the space-time within the event horizon not only funnels down into this central ring but continues through it opening out somewhere, and ‘some-when’ else! This theoretical solution to the black hole situation then led to the idea that a black hole in one part of the universe might open out into a White Hole in another part.

It is tempting to suggest, as you did, that such a white hole might be the beginning of another universe. However as the black hole was only a solution within this universe, and the white hole a speculative extrapolation of that solution, we cannot assume that the white hole actually exists in this universe let alone in another one!

I hope this has helped! As I said in response to a post of yours in another thread – keep reading about the subject you will find it fascinating!

Garth

 

[yanniru]

White holes in the context of baryonic matter passing through the Cauchy horizon was discussed recently on the String/LQG subforum based on a recent series of papers by Hamilton, etal. Here is the link to his last most comprehensive paper:

http://www.arxiv.org/abs/gr-qc/0411062

He considered spherically symmetric, charged black holes. There are a set conditions where dark matter is streaming into the hole and previously captured baryonic matter having been repelled by the charged central region, is streaming outward. The baryonic matter can then pass through a Cauchy horizon and presumably into a new universe as a white hole.

These conditions do not last long- just until the central region accumultes enough mass that the center of mass of the entire local system is moving inward rather than outward.

Richard Ruquist

 

[tumor]

Now we have white holes? what next pink or green holes?

 

[UrbanXrisis]

So a white hole cannot exist because there need to be a black hole. And a black hole cannot exist unless there was already a universe. Am I getting this?

But if the object forming a black hole was rotating then the singularity at the centre becomes not a point but a ring, an annulus.

not sure I understand why it has to be a ring.

 

[Mk]

Mhmm, why's it a ring? Its a long explination, but check out last month's Scientific American.

Sí, white holes only exist when there is a brother black hole, and there can't be a black hole unless there was already a something, like a star or a universe. Here comes in the "Many Worlds" theory of parallel universes, and the theory where energy and matter bubbles up from nowhere...

Ha, ha, wow, tumor, you're going to love this:
http://www.wired.com/news/news/technology/story/19554.html
http://msowww.anu.edu.au/~pfrancis/pink/
http://www.astro.ucla.edu/~kaisler/articles/event_horizon/pinkhole2.html
Actually there are pink black holes... they've found over 100.

Australian astronomers are claiming that not all black holes are black. In fact, some are bright pink.

Paul Francis of the Australian National University, and Rachel Webster and Michael Drinkwater of the University of Melbourne's School of Physics, announced their discovery this week at the ScienceNow forum in Melbourne, Australia.

The scientists said that the pink holes are more than 1 billion light-years away and were discovered using four of Australia's most powerful telescopes, located in the western plains of New South Wales.

Ok, another one, that you're going to love... grey holes, which happen to be pretty much regular black holes, when information escapes from them, they can be called grey/gray.
http://www.nytimes.com/auth/login?URI=http://www.nytimes.com/2004/07/22/science/22hawk.html

Near-extremal black hole are close if not at the minimum possible mass to be a black hole.

If black holes have infinite gravity at its center, and suck in everything inevitabley within its vicinity, why wouldn't white holes be made of exotic matter, and have negativley infinite gravity at its center, and repel everything within its vicinity instead of spew stuff out? That would also obey the 2nd Law of Thermodynamics.

 

[setAI]

big bounce- bouncing singularity- new spacetime- not just a white hole made out of matter/energy- more of an "anti-hole"- it's un-holey- see Smolin's CNS

 

[UrbanXrisis]

Mhmm, why's it a ring? Its a long explination, but check out last month's Scientific American.

Actually, I was just thinking about it and using logic, I can undersatnd why it has to be a ring. Would it be because if the constant rotation of the mass at such a high velocity right? What if the mass wasn't rotating? Would it then be a ball?

Actually there are pink black holes... they've found over 100.

And how can black holes look pink when there are dark matter?

 

[turbo]

And how can black holes look pink when there are dark matter?

These articles about "pink" black holes are a bit inaccurate, as articles about astronomy in the popular press often are. The pictures are pictures of quasars, which are commonly believed to be powered by large black holes that are sucking up local mass at a prodigous rate. The area around these quasars is therefore very energetic. Most quasars are brightest in the shorter wavenlengths and look bluish-white, but some have been found that are pinkish in color. This color originates from the excited field surrounding the quasar's black hole and does not have anything to do with the color of the central black hole itself.

 

[Mk]

Questions!

big bounce- bouncing singularity- new spacetime- not just a white hole made out of matter/energy- more of an "anti-hole"- it's un-holey- see Smolin's CNS

Umm, I didn't quite understand that...

The pictures are pictures of quasars, which are commonly believed to be powered by large black holes that are sucking up local mass at a prodigous rate.

Is it that the black holes are powering the quasars, or the quasars powering the black holes? lol, plowing the ZPE field

And how can black holes look pink when there are dark matter?

Hmmm, black holes are not made of dark matter, they appear black because once light falls in its reach, it doesn't leave.

What if the mass wasn't rotating? Would it then be a ball?

"'Все Перемещается', 'Everything moves'" -Russian Proverb
I don't think it can not rotate. The two known super-massive black holes in the center of the Milky Way galaxy... there's a ball there, the core. I never thought about that. Good question. Maybe because of the overwhelming majority of matter surrounding it?

Can black holes get full? I really can't imagine a black hole sucking up the entire universe, expanding on that: It doesn't absorb radiation, so why does it absorb all light? Would there be sufficent cosmic rays left to evaporate it after a black hole would absorb everything in the universe? When two black holes collide, why does it create a wormhole, and not another super-massive black hole? What happens when a black and white hole collide? They cancel each other out, and what's left is the extra matter from the white hole or, a smaller black hole or nothing left? Or since black holes can't get full of matter, would the black hole just suck up the white hole, therefore the white hole would be inside the black hole, and the black hole would have infinite mass and gravity, creating a rip in spacetime? Or would this be a Schwarzschild wormhole? Is the center of a black hole hot, because of compression? If white holes are made of exotic matter, with negative gravity, would it therefore be an exotic matter black hole? If black holes are constantly evaperating what is the product of evaperation? It must be radiant energy since the black whole would suck it right up, but if the black hole sucks up radiant light energy, why not all energy within vicinity? What about Hawking's proposed, black holes do not evaporate but instead create wormholes? But then how does Hawking and X-ray energy escape?

For black holes of sufficiently small mass it is possible for one member of an electron-positron pair near the horizon to fall into the black hole, the other escaping The resulting radiation carries off energy, in a sense evaporating the black hole. Any primordial black holes weighing less than a few billion metric tons would have already evaporated.

This doesn't sound right... would a black hole give off enough cosmic rays to evaporate itself?

According to general relativity all massive objects possesses an event horizon known as the Schwarzschild radius. This is a surface in three-dimensional space surrounding the object. Any light rays emitted from within this radius are unable to escape. If an object exists entirely within its Schwarzschild radius then it is referred to as a black hole. This radius grows with the mass of the object according to the formula:
[tex]R_s=2mG_N/c^2[/tex]

Do black holes emit radiation in the form of light as well, though it doesn't escape? If an object is caught within the Schwarzschild radius, that doesn't make it a black hole as well, does it? If so, there's not two black holes because the parent one eats up the daughter hole? Again... why not a ball?... hmmm... does it have something to do with its axis of rotation?

In 1915 Einstein developed the theory of gravity called General Relativity. Earlier he had shown that gravity does influence light. A few months later Karl Schwarzschild gave the solution for the gravitational field of a point mass, showing that something we now call a black hole could theoretically exist. The Schwarzschild radius is now known to be the radius of a non-rotating black hole, but was not well understood at that time. Schwarzschild himself thought it not to be physical.

Ok, so maybe a black hole can "not rotate."

Streaming out from the center of the galaxy M87 like a cosmic searchlight is one of nature's most amazing phenomena, a black-hole-powered jet of electrons and other sub-atomic particles traveling at nearly the speed of light. In this Hubble telescope image, the blue jet contrasts with the yellow glow from the combined light of billions of unseen stars and the yellow, point-like clusters of stars that make up this galaxy. Lying at the center of M87, the monstrous black hole has swallowed up matter equal to 2 billion times our Sun's mass. M87 is 50 million light-years from Earth.

How do the particles escape the Schwarzschild radius Wouldn't a particle have to be accelerated to velocity of light?

Since the Earth has a mean radius of 6371 km, its volume would have to be reduced 4 × 10²⁶ times to collapse into a black hole. For an object with the mass of the Sun, the Schwarzschild radius is approximately 3 km, much smaller than the Sun's current radius of about 700,000 km.

 

[Chronos]

...Is it that the black holes are powering the quasars, or the quasars powering the black holes? lol, plowing the ZPE field.

Black holes are the power source.

...Can black holes get full?

No reason to think so.

...It doesn't absorb radiation, so why does it absorb all light?

It absorbs all radiation, including light

...Would there be sufficent cosmic rays left to evaporate it after a black hole would absorb everything in the universe?

Cosmic rays have nothing to do with black hole evaporation.

When two black holes collide, why does it create a wormhole, and not another super-massive black hole?

No wormhole, just a bigger black hole.

What happens when a black and white hole collide?

Since white holes are purely speculative, and probably non-existent, no point in worrying about that until one is actually found.

Is the center of a black hole hot, because of compression?

Unknown and inconsequential, the radiation could not escape.

...how does Hawking and X-ray energy escape?

They are formed outside of the event horizon.

How do the particles escape the Schwarzschild radius Wouldn't a particle have to be accelerated to velocity of light?

They don't, the ones that escape are formed outside the Schwarzschild radius.

Just to clarify, the high energy radiation observed in the vicinity of black holes is emitted by infalling matter. This occurs outside the event horizon. Hawking radiation is created just outside the event horizon. It is, however, much too faint to be detected directly. The only exception would be a mini-black hole, say a few billion tons [which Hawking theorized may have formed in the very early universe] which would be extremely hot compared to their leviathan cousins. It would also have to be very near Earth [within a light year or so]. Even though they are hot, the radiation is in the form of high energy gamma rays. Relatively few photons need be emitted for them to pay off their thermodynamic debt.

 

[Mk]

Ohh, thank you! How is Hawking radiation generated ouside the event horizon?

 

[Chronos]

Hawking radiation is the result of pair formation at the event horizon. One of the virtual pairs falls into the black hole and the other escapes. No longer having a partner with which to annihilate, the escaped virtual particle is promoted to a real particle.

 

[UrbanXrisis]

When the two particles form, why would there be "radiation"?

 

[Chronos]

The term 'particles' is used rather loosely by physicists [they didn't have time to take a lot of english courses with all that math homework to do]. Most Hawking radiation is is composed of massless 'particles' - photons and neutrinos. A small amount is in the form of mass possessing particles and anti-particles. Here is a good summary of the process:
http://www.physics.hmc.edu/student_projects/astro62/hawking_radiation/radiation.html

 

[UrbanXrisis]

what I was wondering is why would the particles that forms release energy when it should take energy to bond?

 

[Chronos]

Because energy and matter are interchangeable under the equivalency principle.

 

[UrbanXrisis]

why doesn't the particles stay as matter? why does it change into energy?

 

[UrbanXrisis]

During Hawking Radiation, why does the 'virtual particles' that becomes a 'real particle' then turn into radiation? What is the force that drives them to do this? Is this somehow related to the galactic jets produced by a galaxy that is rotating around a black hole?

 

[turbo]

During Hawking Radiation, why does the 'virtual particles' that becomes a 'real particle' then turn into radiation?

First, visit the link that Chronos supplied above. It is a nice non-technical explanation of Hawking Radiation. After reading that, come back here.

OK, now that you've read the material in the link: a virtual particle becomes "real" because its antiparticle twin has been captured by the black hole and fails to annihilate it within the time constraints defined by the Heisenberg uncertainty principle. The escaping real particles are what makes up "Hawking radiation". That radiation is a mix of particles, with a wide range of masses and energies. The particles do not turn into some generic "radiation" - that is just a handy term to describe the energy being "emitted" by the black hole.

If you dig into this a bit more, you may be surprised to find that the energy of the black hole's Hawking radiation is inversely proportional to its mass. In fact, the model predicts that large black holes cannot evaporate within the present lifetime of the universe. A black hole MUCH smaller than a solar mass (more like on the order of a Lunar mass) can evaporate within 10-15 billion years or so.