First Stars - How big - Now Black Holes?

[Billy T]

First star-forming gas clouds were much denser. (Early Universe was smaller and prior to stellar fusion also had more hydrogen.) Did not most first generation stars leave Black Holes behind when the rapidly completed their life cycle? How much did the universe expanded while the first stars ran their life cycle and typically formed a pair of gravitationaly bound black holes? Did the typical star pair of the second generation also leave a pair of black holes behind when it died? How many generations before the typical star did not leave a black hole behind? How does the number of these early-generation stellar-core black holes compare with the total number of currently luminious stars? Are there enough black holes to account for "dark matter"? I.e. what fraction of the matter that "condensed" from Big Bang energy is now in black holes?

 

[Labguy]

First star-forming gas clouds were much denser. (Early Universe was smaller and prior to stellar fusion also had more hydrogen.) Did not most first generation stars leave Black Holes behind when the rapidly completed their life cycle? How much did the universe expanded while the first stars ran their life cycle and typically formed a pair of gravitationaly bound black holes? Did the typical star pair of the second generation also leave a pair of black holes behind when it died? How many generations before the typical star did not leave a black hole behind? How does the number of these early-generation stellar-core black holes compare with the total number of currently luminious stars? Are there enough black holes to account for "dark matter"? I.e. what fraction of the matter that "condensed" from Big Bang energy is now in black holes?

A lot of different questions, but all actually tied into one subject of "first stars". Good question(s) too..

I think that a review of the following sites would probably answer all questions at least to some degree. I think that I posted at least one of these before on another thread, but they are all related.

http://www.mpia-hd.mpg.de/GALAXIES/CADIS/irsee2003/PROCEEDINGS/Straka.pdf

http://citebase.eprints.org/cgi-bin/fulltext?format=application/pdf&identifier=oai%3AarXiv.org%3Aastro-ph%2F0405565

http://www.solstation.com/x-objects/first.htm

http://adsabs.harvard.edu/cgi-bin/n...J...567..532H&db_key=AST&high=3cc290f1be15543

http://www.astronomy.com/asy/default.aspx?c=a&id=2968

Let me know if there is still a specific question left...

EDIT: This one is short but has good info:
http://relativity.livingreviews.org/Articles/lrr-2003-2/node14.html

 

[hellfire]

A time ago I read a paper about black hole remnants of population III stars with Joseph Silk as coauthor, but now I was unable to find the reference again. If I recall correctly, it was postulated that most of these black holes merged hierarchically to form the supermassive black holes in the present galaxies. (I don't know whether this is the accepted view; for me it was new and I found it very interesting).

[Edit] I found the reference:
Massive black hole remnants of the first stars I: abundance in present-day galactic haloes
http://arxiv.org/astro-ph/0307171

 

[Billy T]

A lot of different questions, but all actually tied into one subject of "first stars". Good question(s) too..
http://www.solstation.com/x-objects/first.htm
EDIT: This one is short but has good info:
http://relativity.livingreviews.org/Articles/lrr-2003-2/node14.html

Thanks for ref. I looked at them all. Have saved the two best here. Your first was usless for me.

I now understand the importance of "metals" - the presence of bound electrons makes for both rapid radiation and absorption of photons, probably harse UV /soft X-rays. This permits some of the thermal energy to leave (cool) metal containing gas clouds and should also make for greater temperature uniformity. Thus, smaller post generation III stars can form as the gas is less hot and does not require so much to self gravitate / collapse.

I would not however expect uniform density within the gas cloud or for it increase steadly towards a single interior point. Thus I expect at least two regions within the cloud will eat up most of the others and form a pair of stars. The references you gave seem to be describing isolated stars. Perhaps the pairs are so far apart that they do not interact much in the evolution of each; however if all the original angular momentun must be preserved in one star - it seem to me that it could not collapse and heat to fusion temperatures. Also it seems at least poossible the gas cloud could have many condensation centers built on many very small black holes - see next paragraph.

What happened to magnetic monoploes that should have formed? Is my idea that they did, an N one being attracted to an S one and them fusing to form a micro black hole crazy? I have read that one alone might be come a BH because they are so much heavier than protons (10^15 to 10^22 times heaver as I recall reading.) If this is possible, could not these micro BHs pay an important role in condensing gas to start a star up? Nonthing about this in your references. If they do but "evaporate" does this not provide radiation to keep thing ionized (no molecular hydrogen cooling etc?) Would the extremely red shifted remanents of this radiation be seen to day? (like the cosmic background 4 degree radiation) What temperature should it have?

Any idea why the dark matter is thought to separate from baryon/ electron matter? Does not make sense to me. - gravity is gravity is it not? The more I read, the less I know.

Thanks - what do you think of these concerns?

 

[Labguy]

Thanks for ref. I looked at them all. Have saved the two best here. Your first was usless for me.

Pretty charts, though..

I now understand the importance of "metals" - the presence of bound electrons makes for both rapid radiation and absorption of photons, probably harse UV /soft X-rays. This permits some of the thermal energy to leave (cool) metal containing gas clouds and should also make for greater temperature uniformity. Thus, smaller post generation III stars can form as the gas is less hot and does not require so much to self gravitate / collapse.

I can't disagree with any of this part. Not that I know, I'm just not aware of any info to the contrary.

I would not however expect uniform density within the gas cloud or for it increase steadly towards a single interior point. Thus I expect at least two regions within the cloud will eat up most of the others and form a pair of stars. The references you gave seem to be describing isolated stars. Perhaps the pairs are so far apart that they do not interact much in the evolution of each;

For smaller-than-galactic scales I think that you, and some of S.E. Woosley's papers, are correct in this and that large clouds that can retain their angular momentum do, in fact, "fracture into two stars and the pair cannot be separated by ous instruments. This is exactly what Woosley is assuming for the Pistol star that I posted somewhere in the last day or so.

however if all the original angular momentun must be preserved in one star - it seem to me that it could not collapse and heat to fusion temperatures. Also it seems at least poossible the gas cloud could have many condensation centers built on many very small black holes - see next paragraph.

The angular momentum doesn't need to be preserved, and probably can't. See:

http://arxiv.org/PS_cache/astro-ph/pdf/0108/0108070.pdf

where part (pg.2) states that:

Numerical simulations of mergers, with (Mihos & Hernquist 1996)
and without (Hernquist & Mihos 1995) the effects of star formation, show that
gravitational torques cause the gas lose a large fraction of its angular momentum,
up to 99%, in one or two local dynamical times. The gas in these simulations develops
strong inflows and accumulates in the center. Any non-axisymmetric structures, such
as a temporary bar, would speed up the process.

That's a pretty good paper and also points out (pg. 2 also):

In order to prevent the formation of stars, small-scale density perturbations should
be effectively erased or damped. One way to achieve this is to keep the gas hot, with
the thermal speed comparable to the gravitational free-fall velocity; another is to have
an almost relativistic equation of state, where information is again transmitted faster
than the perturbations grow. The latter criterion is satisfied in objects dominated by
radiation pressure and by isotropic (well-tangled) magnetic field.

And, on pg. 5:

a frozen uniform magnetic field is important for
removing cloud’s angular momentum via “magnetic braking” on roughly a dynamical
time of the ambient medium (McKee et al. 1993).

Page 3 also starts the effect of magnetic fields. It's only 6 pages but a good one, I think.

What happened to magnetic monoploes that should have formed? Is my idea that they did, an N one being attracted to an S one and them fusing to form a micro black hole crazy? I have read that one alone might be come a BH because they are so much heavier than protons (10^15 to 10^22 times heaver as I recall reading.) If this is possible, could not these micro BHs pay an important role in condensing gas to start a star up? Nonthing about this in your references. If they do but "evaporate" does this not provide radiation to keep thing ionized (no molecular hydrogen cooling etc?) Would the extremely red shifted remanents of this radiation be seen to day? (like the cosmic background 4 degree radiation) What temperature should it have?

As far as I know, magnetic monoploes can be predicted but have never been detected, Haven't read enough on that to comment. As far as the micro black holes, I'm only aware of those that could have been caused at the BB but would be too short-lived and too small to effect Population III and galactic BH formation significantly. As far as the (2.73K) IRB, the role of massive stars/black holes is discussed at(excellent paper):

http://citebase.eprints.org/cgi-bin/fulltext?format=application/pdf&identifier=oai%3AarXiv.org%3Aastro-ph%2F0308407

Any idea why the dark matter is thought to separate from baryon/ electron matter? Does not make sense to me. - gravity is gravity is it not? The more I read, the less I know.

All I can say is that so little is known (yet) about dark matter that I wouldn't know why it would be affected by gravity any differently. In fact, gravitational effects were how it was first discovered!

 

[hellfire]

Any idea why the dark matter is thought to separate from baryon/ electron matter? Does not make sense to me. - gravity is gravity is it not? The more I read, the less I know.

They sepparate because ordinary barionic matter collapses due to electromagnetic interactions which lead to loss of energy. Non-barionic matter interacts only gravitationally.

 

[Billy T]

Pretty charts, though..

yes pretty, but about as informative to a non professional as flowers, which are also pretty.
...

The angular momentum doesn't need to be preserved, and probably can't. See:
http://arxiv.org/PS_cache/astro-ph/pdf/0108/0108070.pdf

Only skimmmed this ref. I understand that sub galactic regions might interact, if not in actual collisions, via magnetic torques, and tend to reduce their initially larger "local eddy" angular momentum, but even still I suspect that most will still find it easier to from a pair of stars rather than one.
Before reading your ref, a "crazy idea" for shedding angular momentum occurred to me, and it seems reasonable the more I think about it.
Consider a local eddy of pre-stellar gas still cold enough to have some molecular hydrogen (or post generation III with metals) for efficient radiation. If a photon (line radiation) is emitted in the direction of spin, it will have slightly higher frequency (externally measured) than when emitted in the opposite direction. The momentum it carries away is thus slightly larger. How significant is the "breaking mechanism"?

I am going to reply to helfire's comments on my problem with the separation of dark and regular matter - please read and comment also.

 

[Billy T]

They sepparate because ordinary barionic matter collapses due to electromagnetic interactions which lead to loss of energy. Non-barionic matter interacts only gravitationally.

This explains why the regular matter is cooler, not why they separate. In one of Lab guy's references I read that it is thought that the (hotter - I assume) dark matter formed "walls" etc. If anything did so, I would think it would be the colder regular matter, but even then, why does not the dark matter congregate around the condensing regular matter? What am i missing here?

 

[hellfire]

This explains why the regular matter is cooler, not why they separate.

I think cooling it explains the sepparation. The collapse and fragmentation of gas requires energy dissipation. If matter cools, then it looses energy and the orbits will became closer. Thus, the isothermal collapse which leads to a decrease of the Jeans' mass and to a successive fragmentation of a cloud until cooling does not take place, is only possible with baryonic matter. On the contrary, a swarm of non-baryonic particles will never fragmentate into smaller parts; the orbits will be modified due to gravitational interaction, but neither collapse nor fragmentation will take place.

 

[Billy T]

I think cooling it explains the sepparation. The collapse and fragmentation of gas requires energy dissipation. If matter cools, then it looses energy and the orbits will became closer. Thus, the isothermal collapse which leads to a decrease of the Jeans' mass and to a successive fragmentation of a cloud until cooling does not take place, is only possible with baryonic matter. On the contrary, a swarm of non-baryonic particles will never fragmentate into smaller parts; the orbits will be modified due to gravitational interaction, but neither collapse nor fragmentation will take place.

But as i understand it it is the hotter dark matter that is susposed to have condensed and separated. This is waht is confusing me. For example, from Lab guy's third ref (post 2) I read:

"Although dark matter is thought to be relatively segregated from ordinary baryonic matter in outer galactic halos and intergalactic space today, the two may have been mixed initially. As the dark matter condensed into a denser filamentary network, ordinary matter made of hydrogen and helium gas also was gravitationally attracted by these relative concentrations of dark matter, creating Lyman-alpha "forest" clouds of gas. At the nodes of the dark matter filaments, these gas clouds collapsed under gravitation towards of the cores of denser clumps of 100,000 to one million Solar-masses that may have measured around 30 to 100 light-years across and still consisted mostly of dark matter."

What you are explaining to me would be easy to accept if the standard theory were the other way round - I.e. if the cooling of ordinary matter permitted it to condense and then attract the dark matter to the denser aggregates of ordinary matter, but that does not seem to b what the experts are saying happened. See my confusion?

 

[hellfire]

Correct, but what you are describing happens much farther away in past. At the time before of recombination, at redshifts z > 1100, the baryons are strongly coupled to photons, which generate a radiation pressure keeping baryons from collapsing. As dark matter interacts only gravitationally, its density fluctuations may grow at that time as well as earlier. So, well, you could call this growth of fluctuations "collapse of dark matter", but note that the process is very different than in the baryonic case, as it is only driven by gravitation. After recombination, radiation and baryonic matter decouple and the baryons will fall into the gravitational potentials created by dark matter. This is the typical "collapse", which is described in the theory of gravitational instability. This infall into preexisting dark matter potentials is actually necessary in order to explain structure formation, since otherwise there would not be enough time for the baryonic fluctuations to develop after recombination.

 

[Chronos]

Billy, why are you asking these questions? You obviously know the answers to most of them. I find that annoying. hellfire, whom I hold in high regard, is trying to answer them, but, you seem more inclined to argue.

 

[Billy T]

Billy, why are you asking these questions? You obviously know the answers to most of them. I find that annoying. hellfire, whom I hold in high regard, is trying to answer them, but, you seem more inclined to argue.

It is true that I know something about black holes and early universe, but not nearly as much as several others - For example until a few days ago, I was assuming that the first generation of stars were called generation I and that generation III would be the third. Some things I "know" are not well accepted and I want to understand why (change my view if need be etc.) For example, Hawking radiation, I understand well that small BHs have a much stronger gradient just outside their event horizon and assume this helps them swallow only one member of the vacuum polarization pair (leaving the other stable in our universe - at least for a while, much longer than the uncertainty product between E and T would permit, but I have no idea how or why this gets mass out of the BH and makes it "evaporate."

I am very interested in understanding more about BHs, mainly because a pair of them are the villains in my book Dark Visitor In it I consider several non standard possible sources of BHs. Magnetic monopoles being my favorite. They are very heavy, should have been produced in great quantity, but not many seem to be around now - Only evidence of them is the once observed current step in a superconducting ring that did correspond with a single monopole passing thru the ring.

One of my "off beat" theories (I have several - see thread "What Price Free Will" and "Time Does NOT Exist - Math Proof") is that the early universe was not at all like it is thought to be. There was recently some news to this effect also - something to do with there being too many already well formed galaxys, if memory serves.

I think that the magnetic monopoles did form as theory predicts they should have and and unlike the neutral matter (not yet ionized by starlight) they have a long range means of mutual attraction and formed many micro black holes, which served as the seeds for stars formation. I.e. micro BHs are a local gravitational center that is able to collect molecules still too warm to mutually condense into a micro drop of hydrogen as a seed for others to adhere to.

I am not so well informed as others here - so I ask leading questions, trying not to look too foolish by coming right out with some of my "crazy ideas." (that would get them immediately dismissed and me the "crackpot" label I may well deserve, for some of them.) I want to get others to think about things related to BHs. I have succeeded with Space Tiger - he is writing a paper as direct result of some of my questions. Perhaps I will, with my questions provoke the same in Hellfire (or you?) In any case, I am sorry if I annoyed you, but I don't think I am doing anything wrong - perhaps some good, if I induced some guy half my age to publish or even only rethink what he/she "knows." - That is the best thing an old cogger like me can do. - I am too lazy to publish myself any more and not interested in fame, career advancements, or even money with my book, which you can read for free. etc.

PS to SpaceTiger, if you are reading: The more I think about it, the stronger my view that the rate of "vacuum polarization" inside the Earth is OOM lower than in vacuum - The Casimer effect should be strong when the "space between the plates" is essentially zero. I would even accept that there is no vacuum polarization inside "solid" matter. If there is, would it not interfere with the pairing of electrons that permits superconductivity to exist?

 

[SpaceTiger]

I want to get others to think about things related to BHs. I have succeeded with Space Tiger - he is writing a paper as direct result of some of my questions.

That's probably not going to happen, as my studies seem to be indicating that the question I had been pondering is moot. I'm going to keep it in the back of my mind, though. I'll post my work when I'm sure it is or isn't publishable.

PS to SpaceTiger, if you are reading: The more I think about it, the stronger my view that the rate of "vacuum polarization" inside the Earth is OOM lower than in vacuum - The Casimer effect should be strong when the "space between the plates" is essentially zero. I would even accept that there is no vacuum polarization inside "solid" matter. If there is, would it not interfere with the pairing of electrons that permits superconductivity to exist?

I'm not an expert on vacuum polarization, but I'm not sure you understand the magnitude of difference required here. If the 1 kg black hole entered conditions even vaguely resembling a vacuum, the decay would occur in 10^{-16} seconds. Given that there is a lot of empty space inside of a solid lattice (neutral and otherwise), there's no reason to think that the BH would survive for very long. The question is still somewhat open for much larger mass BHs (that is, I'm willing to accept that the Hawking decay limit can be prolonged a little bit), but not for 1 kg.

 

[Billy T]

...I'm not an expert on vacuum polarization, but I'm not sure you understand the magnitude of difference required here. If the 1 kg black hole entered conditions even vaguely resembling a vacuum, the decay would occur in 10^{-16} seconds. Given that there is a lot of empty space inside of a solid lattice (neutral and otherwise), there's no reason to think that the BH would survive for very long. ...

Yes - I have not tried to do the numbers but eating up 1Kg in 10^-16 sec in 0.5 Mev bites (each the rest mass of the surviving member of the vacuum polarization pair) is a tremendous production and capture rate of Vac. Polarization pairs on /near the tiny surface of the event horizon.

I am in no position to argue with Hawking and the few others who can follow him, but as I don't even have the faintest idea how the mass gets out of the black hole to reduce its mass by even 0.5Mev for one swallowed electron, I keep holding my endorsement of the "evaporation" of BHs back - just silly but I never was big on accepting proclamations by small groups when what they are saying just does not seem to fit in with other things I "know." At least I want to hold out for the possibility that inside admittedly very empty "solids" there may be zero production of vacuum polarization pairs. I am also troubled by fact that when the BH swallows an electron, how does it know wheather or not it was a member of a pair. If yes, then lose 0.5Mev of mass, If no, don't lose any mass, instead gain 0.5Mev? That seems silly to me - how is the BH hole so smart?

If there were such horrendous production inside a super conductor, why would some of the recently born positrons not annihilate with one member of the "exchange energy" electrons that can not scatter off phonons? Seem to me that a lot of newly minted positrons inside a super conductor would also in much less that 10^-16 sec have it a normal conductor - after all the total mass of the superconduction electrons is probably less that your one kg of the BH. Further more, the force attracting the positron to the the nearest electron of the super conducting pair is electrical, much stronger than gravity.

I guess I am just too stubborn or worried too much about other implications to swallow things on the bases of authority. Perhaps until you know more about why this is nonsense, we should just agree to disagree on the rate of vacuum polarization inside solids (your "a few OOM different at most" vs my "may not even occur")

 

[SpaceTiger]

I guess I am just too stubborn or worried too much about other implications to swallow things on the bases of authority. Perhaps until you know more about why this is nonsense, we should just agree to disagree on the rate of vacuum polarization inside solids (your "a few OOM different at most" vs my "may not even occur")

Or perhaps you should do the research yourself. Why are you relying on me for this? You seem to have a pretty good grasp of the subject. My intuition (and current theory) tells me that it's not going to work, so it's not really worth it for me to spend the time doing more research. If yours tells you otherwise, then the ball's in your court.

 

[Chronos]

I just wished to comment on tiny black holes in general. The cosmic background gamma ray flux places severe constraints on their numbers [they cannot exist in large numbers].

 

[ray b]

resent findings of metal rich quazars and stars
point to a flaw in the total H with a small He post big bang univerce
it was far lumpier far earlyer then "they thought"
maybe every sized lumps very shortly post bigbang will be proved
sure looks to be heading that way from the newest data

 

[Billy T]

I just wished to comment on tiny black holes in general. The cosmic background gamma ray flux places severe constraints on their numbers [they cannot exist in large numbers].

Can you amplify? I prefer brief explanations as to how gamma rays imply this, but ref is OK.

Small Black Holes, even if more numerious that the currently active stars (as I think they may be.), would rarely even slightly (much less that 1 degree) deflect a gamma ray. Their capture cross section must be an extremely small fraction of the night sky.

I especially doubt gamma rays rule out many small BHs since we are not even sure what makes them. I don't beleve it, but I could agrue that the highest energy gamma rays are the result of "gravity assists" scatterings off of these numerious small black holes. - Seem to be as good as any other explanation I have read.

Again, please justify your claim.

 

[Billy T]

resent findings of metal rich quazars and stars
point to a flaw in the total H with a small He post big bang univerce
it was far lumpier far earlyer then "they thought"
maybe every sized lumps very shortly post bigbang will be proved
sure looks to be heading that way from the newest data

Thanks for the details - I think this was what I read recently and referred to.

 

[Billy T]

Or perhaps you should do the research yourself. Why are you relying on me for this? You seem to have a pretty good grasp of the subject. My intuition (and current theory) tells me that it's not going to work, so it's not really worth it for me to spend the time doing more research. If yours tells you otherwise, then the ball's in your court.

Your right. Position well taken. We all must decide what to do with our remaining time. - What we enjoy doing is high on my list. - Never did like writing papers. I was glad much of my work was classified and could not. I like to discuss ideas, teach a little, and provoke a lot (in the good sense as I have with you.) Unless someone else picks up this ball - it is lost - I don't have the interest in slaming it back with research or publication. Too old and too lazy. Enjoyed our exchange.

 

[RoboSapien]

Try answerin that preRoboSapiens.

I now understand the importance of "metals" - the presence of bound electrons makes for both rapid radiation and absorption of photons, probably harse UV /soft X-rays. This permits some of the thermal energy to leave (cool) metal containing gas clouds and should also make for greater temperature uniformity. Thus, smaller post generation III stars can form as the gas is less hot and does not require so much to self gravitate / collapse.

Ok Mr. Questioniar. I have a question for your above comments.

What will happen to a star that is the size of most massive stars in the Universe and is made up completely out of pure naturally occurring URANIUM ?

What will happen to that star in the end ? or will it ever become a star in the first place even though humans do extract lot of energy out of the element ?

 

[Billy T]

...What will happen to a star that is the size of most massive stars in the Universe and is made up completely out of pure naturally occurring URANIUM? What will happen to that star in the end ? or will it ever become a star in the first place even though humans do extract lot of energy out of the element ?

Not sure I completely understand your question/point but can say a few things I think true and are definitely related to you inquiry, if not right on target:

Does not matter significantly (or at all if we are considering massive collections of matter) what element is making up the large mass so long as the atomic number is greater than iron. Fact that some like Uranium can be split into two (or more) parts in the weak gravity field of Earth does not imply they would do so in the self gravitating mass you are talking about. They will do just the opposite - fall together and form a black hole. However, you will get a lot more energy released than by splitting Uranium from this gravitational collapse to a single point than by merely splitting uranium.

I have been warned, today, about mentioning my book (which you can read for free and which is motivated by my concern that the western world is now beginning process of losing scientific leadership as it has basically already lost technological leadership.) Book is trying to recruit bright student now planning to make more money as corporate lawyers, etc. into science fields by telling a possible cosmic disaster story as vehicle to teach a lot of science to people not currently interested in science. Appendix 3 of that book is a simple calculation (not even calculus required) showing that even a single proton falling into the point singularity gains very large amount of energy (read that as infinite) from the gravitational field. IMHO, it would be appropriated to mention it here. Note that the calculation is too simple, as the physics is very complex, not the classical physics assumed in appendix 3. I do not name book now (publicly) as I am still waiting for the response to my reply to the "warning." - send me PM and I will tell more, including how to read for free.

 

[SpaceTiger]

Can you amplify? I prefer brief explanations as to how gamma rays imply this, but ref is OK.

Small Black Holes, even if more numerious that the currently active stars (as I think they may be.), would rarely even slightly (much less that 1 degree) deflect a gamma ray. Their capture cross section must be an extremely small fraction of the night sky.

I think it's in reference to the Hawking radiation. Tiny black holes would be emitting a lot of it, so we'd see it in the gamma-ray background. If the Hawking radiation turned out to be miscalculated, this limit would of course not apply.

 

[Chronos]

Can you amplify? I prefer brief explanations as to how gamma rays imply this, but ref is OK.

Small Black Holes, even if more numerious that the currently active stars (as I think they may be.), would rarely even slightly (much less that 1 degree) deflect a gamma ray. Their capture cross section must be an extremely small fraction of the night sky.

I especially doubt gamma rays rule out many small BHs since we are not even sure what makes them. I don't beleve it, but I could agrue that the highest energy gamma rays are the result of "gravity assists" scatterings off of these numerious small black holes. - Seem to be as good as any other explanation I have read.

Again, please justify your claim.

Primordial black holes can be much smaller than stellar remnant black holes. The Hawking radiation temperature of a black hole is inversely proportionate to its mass. Stellar mass black holes barely radiate - only a fraction above absolute zero. Small black holes, however, are extremely hot. A primordial black hole large enough to last the current age of the universe - about 10^12 kg - would radiate at a temperature of around 100 billion K emitting high energy gamma rays. If black holes of this size, or smaller, were plentiful, the gamma background radiation would look much different than it does.

 

[Billy T]

Primordial black holes can be much smaller than stellar remnant black holes. The Hawking radiation temperature of a black hole is inversely proportionate to its mass. Stellar mass black holes barely radiate - only a fraction above absolute zero. Small black holes, however, are extremely hot. A primordial black hole large enough to last the current age of the universe - about 10^12 kg - would radiate at a temperature of around 100 billion K emitting high energy gamma rays. If black holes of this size, or smaller, were plentiful, the gamma background radiation would look much different than it does.

Thanks (and to SpaceTiger also). Your point is clear to me now; And as I have said to SpaceTiger several times, very probably correct.

I have tried a few years ago to follow some of the math on this in Rev.Mod. Phys. (Section B as I recall) without much real understanding. I remain troubled by how the mass gets out of the "evaporating BH".

(1)If it by the entropy related very high temperature, I say to myself that gamma rays etc. must come from some hot real surface and they are just EM radiation, like light that can't get out.
(2)If, however, the mass loss is due to the capture of one (only) member of a vacuum polarization pair, in contrast to the capture of an identical particle that has long existed in our universe, my problem is how does the BH hole know what to do (a or b)?
(a)If the captured particle is for example an electron of a vacuum polarization pair, then BH mass drops by 0.5Mev, but
(b) if the unlucky electron has been around for years, BH mass increases by 0.5Mev.

I think all electrons are identical, they don't come with tags that say "I am half of a VP pair", so how is the BH to "know" the history of the electron it has just swallowed?

Hope you can see my troubles - I just am very uncomfortable with this complex theory, the math of which I have not been able to directly follow. Sometimes someone who is not very well versed can ask simple questions better than one who is. That is what I am trying to do. Can you shed any light (or mass ) on this? Thanks in advance.

 

[Billy T]

...A primordial black hole large enough to last the current age of the universe - about 10^12 kg ...

I DON'T WANT TO STEP IN BETWEEN A CROSS FIRE BUT:

I note an an exteme disconnect between your value for lifetime and that of SpaceTiger's. In severl posts (16 and before this thread) he has been stating that a 1kg BH lasts only 10^-16sec.

If universe is 14 billion years old and there are 3600x365.25x24 sec per year, your lifetime is 31,557,600x14x10^9sec or call it at least 3.1x1.4 x 10^17= 4 x 10^17 sec. which when compared to his 10^-16 sec is mor than 4x10^31 times longer, yet your mass is only 10^12 larger.

While on the subject of older post of this thread, what do you think of my agrument that the quantum exchange energy pairing, which makes superconductivity possible, would be rapidly destroyed if vacuum polarization did occur at anything near the rate SpaceTiger thinks it does in the "empty" space inside "solids" - Seem to me the the VP positons would often annhilate one member of the energy exchange pair and force the super conductor back to the normal state. Any view on this as a counter argument to VP, at least in inside "solids"?

 

[Labguy]

(1)If it by the entropy related very high temperature, I say to myself that gamma rays etc. must come from some hot real surface and they are just EM radiation, like light that can't get out.
(2)If, however, the mass loss is due to the capture of one (only) member of a vacuum polarization pair, in contrast to the capture of an identical particle that has long existed in our universe, my problem is how does the BH hole know what to do (a or b)?
(a)If the captured particle is for example an electron of a vacuum polarization pair, then BH mass drops by 0.5Mev, but
(b) if the unlucky electron has been around for years, BH mass increases by 0.5Mev.

I think all electrons are identical, they don't come with tags that say "I am half of a VP pair", so how is the BH to "know" the history of the electron it has just swallowed?

Chronos is correct (and SpaceTiger) about the mass-energy production of a black hole (BH) by way of Hawking radiation (HR). That is limited strictly to the "lifetimes" and energy release of a non-accreting black hole. Your example (a) and (b) above are of two different things. Of course, a black hole with other matter being accreted (your (b) above) will gain mass as long as the accretion rate exceeds the Hawking evaporation rate.

So, forget about a black hole sucking in matter of any kind and place it alone in a relatively empty region of space, at least empty enough to not draw in any nearby matter. This is where we can talk about the effects of Hawking radiation alone. So, use (a) in your post above. The energy at the event horizon is as Chronos explained. This energy will produce virtual-particle (VP) pairs and not just electrons as has been mentioned so far. The VP pair is produced by "borrowed" energy from the BH. The Heisenberg uncertainty principle allows for two things here. (1) It allows the VP pair to exist on borrowed energy for a finite, but very short, period of time, and (2) it allows the VP pair to be of any energy amount as long as, again, anything borrowed is returned. Therefore, the VP pair is not limited to just electrons and positrons being discussed so far, it can also be quarks, protons, neutrons, and certain mesons regardless of energy required to produce the pair.

So, one of the "virtial" particles falls back into the BH and the other becomes a "real" particle with real mass. If it escapes into space (sometimes both will fall back in), then the mass of whatever the escaping particle was will exactly match the mass-loss of the BH. Mass is delivered into the realm of real and the BH loses that much mass, so the first two laws of thermodynamics are still happy, nothing has been violated.

How does a small BH become so hot and evaporate so fast? (One might ask.. ). Well, the "standard" HR process just mentioned was about one, single VP pair. In a large BH idling along this migh be the case here and there around the EH. But, in a smaller BH with more energy per square^anymeasure will be producing VP pairs, of many different particle types, at a great pace. Now we have a swarm of real particles buzzing all around the EH at a very high density. Some will combine into more complex particles, but most will just escape or, to produce the intense energies mentioned, many particle-antiparticle pairs will meet and annihilate into pure energy. If the density is high enough and the particles massive enough, you will see the gamma-ray production Chronos mentioned, again, especially from small, short-lived BH's. Of course, it is actually the entire EM spectrum of photons that are produced but the gamma rays get the most attention.

EDIT: Add;
http://superstringtheory.com/blackh/blackh3.html

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

http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/hawking.html

http://library.thinkquest.org/C007571/english/advance/english.htm?tqskip1=1&tqtime=0602

http://relativity.livingreviews.org/Articles/lrr-2001-6/

http://www.physics.hmc.edu/student_projects/astro62/hawking_radiation/radiation.html

 

[Billy T]

I have not had time to visit your refs yet but will. I want to thank you for taking the time/ effort to respond so well, but there is a slight misunderstanding of why I mention (b) the capture of one long existing electron.

...Of course, a black hole with other matter being accreted (your (b) above) will gain mass as long as the accretion rate exceeds the Hawking evaporation rate. So, forget about a black hole sucking in matter of any kind and place it alone in a relatively empty region of space, at least empty enough to not draw in any nearby matter.

That was my assumption. SpaceTiger has lead me to believe that a 1kg BH would only last 10^-16 sec, being eaten away in 0.5Mev bites -that is a lot of bites even if we switch to protons/ anti protons (1Gev bites). Surely the picture does not change much if I assume that one innocent old electron is eaten before the BH "evaporates" away. I was just trying to focus your attention on fact that somehow BH knows that this electron is different from all the others that in that it causes a mass gain - not very significant in the big picture, but troublesome, at least to me, as it seems to require that this electron comes whit the tag (LOL) or that the BH "knows"
it history/origin.

The VP pair is produced by "borrowed" energy from the BH. The Heisenberg uncertainty principle allows for two things here. (1) It allows the VP pair to exist on borrowed energy for a finite, but very short, period of time, and (2) it allows the VP pair to be of any energy amount as long as, again, anything borrowed is returned.

I understand well that E and T operators do not commute under the Hamiltonian and thus the uncertainty principle applies to the product of the uncertain (errors on epistimology if you like) product and certain think VP is defined better as you do and should not be only fermions. However, this "borrowing" concept leaves me very cold - There does not need to be any BH around for VP to occur. The Casimire effect (real lab measurement) proves this as well as the fact that the vacuum polarization is well accepted theory, not requiring BHs. That is "borrowing" from BH is justified way of thinking / book keeping perhaps, but has nothing to do with the physics -the black hole is not some credit bank that will lend mass for short period. Quantum Mechanics does that just fine in the absence of BHs!

Everything you say is no doubt true in some sense, but it does not help me understand how the mass gets out when one member (only) of a VP is eaten and yet in the very rare case that an identical old particle is eaten, the BH gains mass. That is my mystery/ confusion/ reluctance to sign on board and accept what I can not understand, just because "authorities" (and a very small group at that) tell me it is so. If money were envolved, i would bet they are right, but we are talking about ideas here.

Got to go now - if need to address more and chroot has not barred me form PF, I will continue later.

thanks again and in advance if you comment on the above.

 

[SpaceTiger]

If universe is 14 billion years old and there are 3600x365.25x24 sec per year, your lifetime is 31,557,600x14x10^9sec or call it at least 3.1x1.4 x 10^17= 4 x 10^17 sec. which when compared to his 10^-16 sec is mor than 4x10^31 times longer, yet your mass is only 10^12 larger.

Actually, the discrepancy is larger (4x10^33, you made a mistake in that last step). The reason, of course, is that the evaporation time goes as M^3.

 

[Labguy]

The Casimire effect (real lab measurement) proves this as well as the fact that the vacuum polarization is well accepted theory, not requiring BHs. That is "borrowing" from BH is justified way of thinking / book keeping perhaps, but has nothing to do with the physics -the black hole is not some credit bank that will lend mass for short period. Quantum Mechanics does that just fine in the absence of BHs!

Sure, vacuum polarization is accepted, but remember that it is energy that creates the VP pair. In "open space" there is a bit of energy available for Vacuum fluctuations (vacuum polarization) but near the EH of a BH the energy is much greater.

Everything you say is no doubt true in some sense, but it does not help me understand how the mass gets out when one member (only) of a VP is eaten and yet in the very rare case that an identical old particle is eaten, the BH gains mass. That is my mystery/ confusion/ reluctance to sign on board and accept what I can not understand, just because "authorities" (and a very small group at that) tell me it is so.

There is "negative energy" that is borrowed and then returned to the BH to allow one of the VP pair to become a real particle. I think I already explained that when energy is lost from a BH to create a "real" particle, it is exactly the same as a mass loss since mass=energy. Beyond that, I guess you would just probably have to do some more reading to grasp the concept, and the math ain't too tough on that level either...

 

[turbo]

Everything you say is no doubt true in some sense, but it does not help me understand how the mass gets out when one member (only) of a VP is eaten and yet in the very rare case that an identical old particle is eaten, the BH gains mass. That is my mystery/ confusion/ reluctance to sign on board and accept what I can not understand, just because "authorities" (and a very small group at that) tell me it is so. If money were envolved, i would bet they are right, but we are talking about ideas here.

I don't want to complicate your quandry unneccesarily, but that's my true calling. If gravitation and inertia can arise from the interaction of mass with the vacuum field (ZPE) as proposed by Sakharov and others, we should expect that the ZPE field is susceptible to polarization. If the particle/antiparticle pairs are preferentially oriented by the presence of a black hole in such a way that the antiparticles are more likely to cross the event horizon, the two things will happen:

1) a real particle will be created outside the event horizon adding imperceptibly to the domination of matter over antimatter.
2) the antiparticle will annihilate a particle inside the event horizon causing the black hole to lose mass.

I think Hawking is right, but only if the ZPE field is polarized by mass to encourage the absorption of a net excess of antiparticles from the virtual pairs.

 

[Chronos]

I DON'T WANT TO STEP IN BETWEEN A CROSS FIRE BUT:

I note an an exteme disconnect between your value for lifetime and that of SpaceTiger's. In severl posts (16 and before this thread) he has been stating that a 1kg BH lasts only 10^-16sec.

If universe is 14 billion years old and there are 3600x365.25x24 sec per year, your lifetime is 31,557,600x14x10^9sec or call it at least 3.1x1.4 x 10^17= 4 x 10^17 sec. which when compared to his 10^-16 sec is mor than 4x10^31 times longer, yet your mass is only 10^12 larger.

While on the subject of older post of this thread, what do you think of my agrument that the quantum exchange energy pairing, which makes superconductivity possible, would be rapidly destroyed if vacuum polarization did occur at anything near the rate SpaceTiger thinks it does in the "empty" space inside "solids" - Seem to me the the VP positons would often annhilate one member of the energy exchange pair and force the super conductor back to the normal state. Any view on this as a counter argument to VP, at least in inside "solids"?

SpaceTiger already answered the technical part. The formulas for black hole mass vs evaporation rates and temperature are simple and easily found. I'm not sure I even know what 'quantum exchange energy pairing' means, or the connection between vacuum polarization and superconductivity - so I can't offer an informed opinion.

 

[Billy T]

In another very related thread, (post 18 of "mass in black hole") LabGuy was becoming annoyed with me, and I am sorry for that as he has been very patient and helpful. Several times I have admitted that the standard views about "Hawkings Radiation" removing mass from BHs is probably correct, despite lack of any mechanistic explanation or observational evidence (Even much less accepted as real monopoles have one observation - the correct size current step in a superconducting ring and as I understand it, common agreement among BB experts that they should (based on theory of BB evolution) have been created in the condensation of energy of the early universe.)

LabGuy was annoyed by my post 17 in which I tried to focus attention on the fact that the mass of a BH is concentrated in a point singularity by noting:

"... consider a black hole at time when its mass is just beginning to drop thru 100Kg and then very shortly later when its mass is 99kg. How did that 1kg "get out" from the point singularity?"

If the mass of a BH were filling the interior of the event horizon, I would not have so much trouble understanding the simple energy conservation law: (If one member of VP pair escapes to live much longer than the Energy x Time uncertainty product permits because other it should have annihilated with is eaten, then it rest mass, and its KE, must be removed form the BH.) I would still be interested to have some mechanistic idea as to how it happened, but at least it would not require something changing at location "B" to explain another change at remote location "A" when the space around "B" is so badly warped that nothing can get out from "B" to go to "A".

In the case of the point singular mass, well separated from the EH, I am more disturbed - How does the required mass get out from the singular point to the escaping particle, and then beyond into the outside world? How does it even travel out to the EH, when nothing can? In what form is it during this transit? Is this some type of "action at a distance" (unexplained mass migration outward) mediated by the exchange of some new "virtual particles" between the point singularity and the EH? It is all very strange, if you stop to think what the convenient, conventional, words are saying.

The answer may be "That is just the way nature is - like quantum entanglement - impossible to give any satisfactory physical / mechanistic explanation." If that is the case, let's be honest and say it.

The words: "the VP pair 'borrows' energy/mass from the BH are not any explanation to me. (My favorite example of this type of verbal trick, subsituting for a real explanation that says something about the mechanism used is: "Morphine makes you sleepy because it contains a narcoleptic agent.") To me BH "mass loss /evaporation" via "VP and associated HR" are not explanations. I would much prefer to admit /say: "that is what current math indicates, and like quantum entanglement, your are never going to feel good about how it works."

LabGuy has also recommended to me that I read up on it more. At the level I can easily understand, it is very hard for me to see that the "explanations" (like those given above or in the quasi-lay references he has supplied), differ significantly from the above one as to why morphine makes you sleepy.

About two years ago, I spent the 5 hours (lunch til dinner time) with Section B of the Physical Review (three most recent years). After about an hour spent skimming, I had selected four or five papers to read. - I found it rough as so much is fine details that one must already be working in the field to fully understand the point - I once had reasonable proficiency with tensors, in that I could follow, but I never was good enough to derive anything, as I once could with quantum formulations, but that was years ago and that was part of my problem. So now let me just try to get one idea clear, with LabGuy's (or other's help):

In post 31 of this this thread LabGuy said: (not exact quote):
"... bit of energy avilalbe ... in open space...but near EH of BH, energy is much greater..." You know more than I do about this, so I bet you are correct, but let me tell how I understood the fact that HR is only significant for small BHs:
(1) I thought the production of VP was something that fell out of the fact operators for E and T don't commute under the Hamiltonian so for short times energy does not need to be conserved (no "borrowing" from the BH required) and
(2) the the rate of VP production had nothing to to do with the distance to or from any BH, but is determined solely by the facts and associated calculations stated in point (1), and
(3) that the reason why only small BHs "evaporate" is that only they have a gravitational gradient strong enough to separate the members of the VP pair before most of them recombine. (There have been at least theoretical studies that show the strength of the electric field (between condenser plates) that is required to separate VP pairs before they recombine - I think grvitational gradient is playing much the same role (obviously gravity produces only accleration, not separation.)

If I understand your text quote above, you disagree with at least point (2). But If you can tell me why and if any of my two others are in error.

Again let me thank you for all your prior help - I am honestly trying to get some sort of handle on this, but willing to give up if it is impossible. (I have given up on quantum entanglement. - So it would not be the first time for me.) What I don't want is a lot of empty words like:

"Energy must be conserved, a new particle now exist in our observable universe, therefore the mass of the BH must decrease." etc.

I want a few words about "how." What mechanism(s) are involved? How does the mass get from the point singularity to reside in the new escaping member of the VP pair? Does it transit from the singularity to the escaping particle in less time than the escaping particle to BH point distance divided by speed of light? The words "borrowing" and "explanations" like the prior paragraph quote just leave me cold, or worse - I feel like someone was trying the old verbal trick (like the morphine one cited above.) on me.

 

[Chronos]

Billy, quantum physics is not intuitive, so it's very difficult to express in simple terms. Hawking radiation is a quantum phenomenon. Like most quantum phenomenon, it defies classical reasoning. It is also theoretical. We don't have a ready supply of black holes to study and quantify the effect [which may not be all bad]. All the science we do know insists it must exist, but that does not guarantee it does. I think it would help if you just forget about virtual pairs and focus on the quantum tunneling explanation. It's almost always better to rely on explanations that make sense to you. At least you will understand why they are wrong, if disproven.

 

[turbo]

(3) that the reason why only small BHs "evaporate" is that only they have a gravitational gradient strong enough to separate the members of the VP pair before most of them recombine. (There have been at least theoretical studies that show the strength of the electric field (between condenser plates) that is required to separate VP pairs before they recombine - I think grvitational gradient is playing much the same role (obviously gravity produces only accleration, not separation.)

I believe there is a problem with this concept that only small BHs evaporate. All non-accreting BHs can evaporate through the Hawking radiation scheme. Any BH can evaporate, as long as the mass/energy of its Hawking radiation exceeds that of its infalling real matter.

 

[Billy T]

I believe there is a problem with this concept that only small BHs evaporate. All non-accreting BHs can evaporate through the Hawking radiation scheme. Any BH can evaporate, as long as the mass/energy of its Hawking radiation exceeds that of its infalling real matter.

True, but be reasonable (and understand that "small" means masses very significantly less than the BHs formed by iron core stars collapsing.)

Stellar core BHs evaporate so slowing that I bet the "dark enegry" that will tear apart even the nucleus of all atoms, if you wait long enough, may destroy them first - Just guessing, no calculation, and trying to show that it is not "reasonable" to pick fault with my "only small BHs evaporate" statement.

 

[Billy T]

...I think it would help if you just forget about virtual pairs and focus on the quantum tunneling explanation. It's almost always better to rely on explanations that make sense to you. At least you will understand why they are wrong, if disproven.

Thanks for the suggestion. I think you are right - I.e. tunneling is a mechanism and something I understand, having calculated the leakage of "particle" initially 100% in potential well "A" into well "B" and back again. (Wells "A" & "B" have infinitely high barrier, not too thick between them)

Fact that the classic physics problem of two weakly coupled oscillators does exactly the same thing, also helps one feel good about tunneling, not to mention it is easily demonstrated and now the basis for some commercial devices. Also, as I understand well where the uncertainty in the E & T product comes from, the violation of energy conservation in the exponential part of the wave function inside the barrier does not bother me.

Unfortunately all this talk about VPs and /or temperature related to entropy tends to distract one from tunneling, which does provide no mechanism for getting the mass out of the point singularity and into our unverse.

I am too lazy to do it, especially since it requires a 3D well calculation, but it would be interesting to see if some tunneling model with a infinitely high barrier between the point singularity (or very small sphere - see next paragraph) and the EH does give the same time scale functional dependence against mass (lifetime proportional to M cubed).

Hope it does. If it does, then I will stop thinking about how small BHs "evaporate" AND make it a rule not to read any more of these "pseudo explanations" about "borrowing mass from the black hole" or about "hot, non-existent EH surfaces radiating almost as black bodies" etc.

Reason I suggest (to anyone willing to do the work) that the BH be modeled as a small sphere (a few Plank radii?) instead of a singularity, is that in the limit as the "sphere" goes to zero (point singularity) the ground state energy of the "trapped mass particle" will go to infinity and such energy probably tunnels quickly, or makes the whole calculation nonsense. etc.

Again, thanks for focusing my thoughts in what I expect is a much more satisfying direction.

 

[Billy T]

Actually, the discrepancy is larger (4x10^33, you made a mistake in that last step). The reason, of course, is that the evaporation time goes as M^3.

Thanks - I remembered it as linear in M and that was my first problem.
Second is I am mildly dyslexic. I of course know that 17 + 16 = 33. Trouble was that "17" activated the neural circuits in my brain that recognize "1" and "16" did the same. More activation of the "1 circuits" came when I mentally added 6+7=13. (which for a dyslexic is easily 31)
I got the "carry 1" ok but that was still more activation of "1 circuits" With all that 1 activity when I wrote down the 3 of 30, I was not able to write it again to get the correct 33, but produced 31.

I know a good bit about how the mind functions - there is a well recognized effect in mental processing called "inhibition of return." - It is very useful, for example, if you have just made a saccade to some visual field point, you function better if you don't return to fixate that point again too soon. This may also have been part of my problem - I had just produced a "3" and it may have been harder to produce another - not sure of this, as this is a little different form of "inhibition of return" than is the standard version.)

Some of you who want to know more of my views about mental functions, which are very non standard, but well supported, might take a look at the attachment to the first post of the philosophy thread I started called "What Price Free Will." (I give there three independent proofs that the standard view of perception accepted by almost all cognitive scientists is simply wrong. - Does not prove my view is correct, but exposes need for reform.)

Clearly off subject, but hope you all found the above interesting - to "see" inside the mind of a dyslexic. ( I always like to understand why I make these types of mistakes.)

 

[Billy T]

...If the particle/antiparticle pairs are preferentially oriented by the presence of a black hole in such a way that the antiparticles are more likely to cross the event horizon, the two things will happen:
1) a real particle will be created outside the event horizon adding imperceptibly to the domination of matter over antimatter.
2) the antiparticle will annihilate a particle inside the event horizon causing the black hole to lose mass...

I have some doubts about both 1 & 2.
ON 1:
I am old enough to have learned my quantum mechanics back when "CPT" was "reversable" or what ever term was used - I forget - idea was you could reverse the sign of any two and physics did not change. I especially liked switching the charge and and replacing t by -t because then an electron scattering could become a positron traveling backwards in time, which if it at some earlier time scatted (with C & T again reversed) would be an electron from the past traveling forward to "now" - that is at time "now" we could have two views of the same electron. If two are possible, why not N views where N is the total number of electrons in the universe? A wonderful (if hard to believe) reason why all electrons are identical. As far as i know, no one has any other idea why this is true.

What does this have to do with your (1)? Well a few years later a couple of smart oriental guys got the Noble prize for showing only CT were "reversible" and that in some weak reactions (as i recall) there was a slight bias for one of the parities, and as a result of this the universe is matter, not anti-matter. I can see no reason to think that the probability of one type of matter in the VP pair should be found closer to the BH, nor is there now any need to postulate this as the mechanism that made the universe matter as opposed to anti -matter.

On 2:
The mass loss would be identical regardless of which matter form gets eaten. I also doubt if it makes much sense to think that the mass at the singularity of a BH is matter (or anti matter) only - but this is way beyond my capacity to know anything for sure.

 

[Labguy]

LabGuy was annoyed by my post 17 in which I tried to focus attention on the fact that the mass of a BH is concentrated in a point singularity by noting:

"... consider a black hole at time when its mass is just beginning to drop thru 100Kg and then very shortly later when its mass is 99kg. How did that 1kg "get out" from the point singularity?"

If the mass of a BH were filling the interior of the event horizon, I would not have so much trouble understanding the simple energy conservation law: (If one member of VP pair escapes to live much longer than the Energy x Time uncertainty product permits because other it should have annihilated with is eaten, then it rest mass, and its KE, must be removed form the BH.) I would still be interested to have some mechanistic idea as to how it happened, but at least it would not require something changing at location "B" to explain another change at remote location "A" when the space around "B" is so badly warped that nothing can get out from "B" to go to "A".

In the case of the point singular mass, well separated from the EH, I am more disturbed - How does the required mass get out from the singular point to the escaping particle, and then beyond into the outside world? How does it even travel out to the EH, when nothing can? In what form is it during this transit?

No, I don't care, and neither do the virtual particles, whether the mass in a BH is in a point singularity or one of a finite size. Actually I don't believe that any singularity needs to exist as usually defined. That is, a point or ring of zero volume and infinite density. I don't believe in infinite densities. (another story).

But, you are totally wrong and misconceived when asking how particle(s) "get out" of the central mass of the BH to the event horizon. There is no need for matter to "travel" as you put it. No need to "travel" from point A to point B. First, answer this for me. You have posted much here about vacuum fluctuations (vacuum polarization) where VP pairs are constantly being produced and annihilated in all of space. You have mentioned the Casimir effect several times. So, how do the particles "get there" from somewhere else? Do they have to travel magically from some other place where mass/matter exists to that empty place in deep space? The answer is of course not!

What you seem to be missing is the concept that matter and energy are the same thing. Why aren't you questioning the possibility of vacuum fluctuations?? Where do the particles travel from (your point A-pointB)?? If forced to answer these questions, wouldn't you say that the VP pair, any type of matter formed there, is formed for an instant from pure energy? If you answer no to this and insist that the particles have to travel from another matter source, then the discussion is over and you can't even sensibly discuss vacuum fluctuations, much less Hawking (not Hawkings) radiation.

BUT, if you grasp the concept of matter being formed (on-the-spot) from pure energy, then transferring that understanding to BH Hawking radiation should be a breeze. For instance:

(1) There is much energy at the EH of a BH, especially a small BH.
(2) The VP pair did not have to "travel" from the singularity to the EH!
(3) The pure energy at the EH causes the production of the VP pair!
(4) The VP pair did not have to "travel" from the singularity to the EH!
(5) If the VP pair separates and one escapes, there is a mass loss to the BH.
(6) The VP pair did not have to "travel" from the singularity to the EH!
(7) How does the BH lose mass = to the mass of the escaping particle?
----a. Matter and mass can (for this part) mean the same thing.
----b. Mass and energy are the same thing! Some guy said that e=mc²
----c. When the particle escapes, it takes ENERGY from the EH with it.
----d. The VP pair did not have to "travel" from the singularity to the EH!
----e. The ENERGY at the EH is gravitational energy!
----f. If the BH loses ENERGY, then it loses MASS.
----g. The BH loses MASS because mass and energy are the same thing.
----h. The VP pair did not have to "travel" from the singularity to the EH!
----i. The VP that falls back into the BH converts back to energy. It doesn't have to "travel" or "meet-up" with it's anti-particle type to annihilate. That's why it is called "Virtual" in the first place!
----j. The VP did not have to "travel" from the EH back to the singularity!

That's all I have to offer on this topic and will be my last post back onto this thread. Thanks for your concern..

 

[Billy T]

LabGuy: We have not been communicating very well.
(1)In earilier post I noted that an old electron being captured added to the BH mass whereas one of a VP caused it to decrease. I only intended the capture of one electron but you began to explain that: "Of course, if BH was acquiring mass faster than it was radiating it way, then sure it would not evaporate." (not exact quote)

What I had said was (quoting from post 29, with typos corrected):

"Surely the picture does not change much if I assume that one innocent old electron is eaten before the BH "evaporates" away. I was just trying to focus your attention on fact that somehow BH knows that this electron is different from all the others in that it causes a mass gain - not very significant in the big picture, but troublesome, at least to me, as it seems to require that this electron comes with a tag (LOL) or that the BH "knows" its history/origin."


(2)Another communication failure, which I really can not understand how it occurred, is your reading my recent post as if I were trying to insist that it was a particle that left the point singularity, rather than just that something happen at the point singularity as result of something happening at, or just outside, the EH. I even asked what form was the transer of the mass/energy between points A & B - clearly indicating that I was not assuming it to be particle or even mass. I even suggested that perhaps some "exchange" of new "virtual particles" could be postulated.

What I said was (quoting from post 34, with typos corrected):

"I would still be interested to have some mechanistic idea as to how it happened, but at least it would not require something changing at location "B" to explain another change at remote location "A" when the space around "B" is so badly warped that nothing can get out from "B" to go to "A"."

Note that initially I spoke of "change," not "mass," not "energy," but just used the very general term "change." Because the nature of the change I was referring is a decrease in the mass, you assumed that I was stating in my 100kg black hole decreasing to a 99kg example that I though 1kg of mass was actually moving / traveling out from the BH point.
What I was trying to do was the same thing that Einstein tried to do with the famous ERP paper. Namely, to point out that if "action at distance" was obviously unthinkable (Einstein called it "spooky") between two points A & B which were able to exchange information (but delayed by at least the transit time of light) then surely it was more ridiculus to think that a change at "B" (the Black Hole point singularity) was the instantious result of a change at "A" (the location of the VP pair member which alone escapes to have life longer than permitted by the uncertainity principle E x T product, because no information can flow from any point inside the EH to the region outside the EH. You with your "borrowing energy from BH for VP production" concept seemed to be suggesting that it was even "anticipatory" (faster than "instantious")

As it turned out, the ERP paper which predicted the spooky "quantum entanglement" as a way to show QM was faulty, backfired on Einstein (who was dead before "quantum entanglement" was demonstrated to be true,. but very mysterious part of nature) - quantum entanglement is such a mystery that I for one have abandoned any hope of feeling good about understanding it.

I have never seen anyone else point out that "supperconductivity" is also a strong demonstration of this "spooky action at a distance," at least if the theory of Bardin, Cooper and "X" is still the accepted view. (It is more than 30 years since I looked into supperconductivity and I may not have their names correct and note that three, not two people developed the theory, but I can't remember the name of the third, "X".) This is because the two electons that are quantum mechanically "joined" by "exchange energy in phase space" do not need to near each other in real space. The basic idea of the BXC theory of supperconductivity is that when one of the "joined pair" hits a lattice defect or a thermal phonon, its partner does not so it does not scatter and lose energy as it would in a normal conductor. That is, a change in the momentum of the electron at "A" is prevented instantiously by the partner at "B" which may be meters away in real space. I have mention superconductivity in several threads, related to VP production and lifetimes of micro black holes inside solid matter, as SpaceTiger will surely confirm, but never before have I so explicitly stated why supperconductive is also related to this VP and evaporation of BHs question.


(3)Still another communication failure, also very hard for me to understand, is your believe that I think VP particles must come from somewhere else. I even explained the it was the noncomuting nature of the E & T opperators under the Hamiltonian, which leads to the uncertainty principle, which then permits VPs to be locally produced in very short term violation of conservation of energy. How you could get the idea that I think they come "from somewhere" in view of these statements of my is beyond my commprenhension. So my answer to your question below is of course they do not come from somewhere else, they are locally produced "from nothing."

I suggest VPs come "from nothing" rather than "from energy available near a BH" as you seem to be stating. Several times you have noted that:

(a) There is little energy available in open space, but a lot near a black hole. and
(b) The energy for the VP pair is "borrowed" from the black hole for their creation.

I think this view of yours is wrong because (as I have stated several times):

(a) It is uncertainty principle, not being near a black hole, which permits this brief "something from nothing" production of VP pairs. and
(b) It occurs at the same rate (a quantum mechanical calculation that makes no referrence to black holes or any other gravitational source) through out all "empty space." and
(c) VP production is a brief violation of "conservation of energy" not a "loan from a near by back hole" which preserves "conservation of energy". and
(d) The Casimir effect, which has been measured in the lab, proves the reality of VP production far from Black Holes, at the rate predicted by the calculations of point (a)
(e) That the reason why small black holes "evaporate" has nothing to due with some black hole enhancement of the VP production rate (a violation of the QM calculation of point a) but is due to the much stronger gradient in the gravitational field near the EH of a small BH. That is, a much greater fraction of the constant VP production have one (and only one) member of the pair "sucked" in side the EH, leaving new "mass/energy" in our observable universe.

These are some of the reasons why I was "left cold" by your idea that the energy had to be "borrowed" from the BH and the abundant "energy near the black hole" for VP production was why small BHs "evaporate." Like Einstein (although certainly not to be compared to him) I want some understandable mechanism for how the black hole mass is reduced. For me the words that seem to satisfy most people ("Hawkings-Radiation, one VP member escaping" and / or "black body radiation from the very hot EH 'surface'," (high temperture inferred form all the entropy the BH has swallowed) are just "empty words" not any more of an explanation than "Morphine makes you sleepy because it contains a narcoleptic agent." It should bother most everybody that there are two entirely different sets of these "empty words" - one related to high temperatures and the other related to escaping member of a VP pair!

I also understand well that energy and mass are the same thing. I even believe that two packets of "pure energy" have a gravitational attraction between them.

In summary we agree on most things except points a,b,c and e above.

...But, you are totally wrong and misconceived when asking how particle(s) "get out" of the central mass of the BH to the event horizon. There is no need for matter to "travel" as you put it. No need to "travel" from point A to point B. First, answer this for me. You have posted much here about vacuum fluctuations (vacuum polarization) where VP pairs are constantly being produced and annihilated in all of space. You have mentioned the Casimir effect several times. So, how do the particles "get there" from somewhere else? Do they have to travel magically from some other place where mass/matter exists to that empty place in deep space? The answer is of course not!

What you seem to be missing is the concept that matter and energy are the same thing. Why aren't you questioning the possibility of vacuum fluctuations?? Where do the particles travel from (your point A-pointB)?? If forced to answer these questions, wouldn't you say that the VP pair, any type of matter formed there, is formed for an instant from pure energy? If you answer no to this and insist that the particles have to travel from another matter source, then the discussion is over and you can't even sensibly discuss vacuum fluctuations, much less Hawking (not Hawkings) radiation.

I too would not discuss, at the level we are trying to, with anyone who thought what you seem to think I do either.(With your incorrect "understanding" of my view, I would never have been as patient as you have been, so I again thank you.)

In hope you will at least agree tht we have been having serious "communication failures" in addition to what appears to be a real disagreement over the cause of VP production, which we both agree then leads to BH evaporation. (My VP production rate is a QM calculation constant through out all of "empty space" vs your VP production rate is greatly enhanced near a BH because of the much greater "availability of energy near a BH" for "loans / borrowing" that conserver energy" )

 

[Billy T]

I have spent a couple of hours reviewing the Casimir effect, and find that I should revise at least (b) of comments (a thru e) I made in prior post:

"(a) It is uncertainty principle, not being near a black hole, which permits this brief "something from nothing" production of VP pairs. and
(b) It occurs at the same rate (a quantum mechanical calculation that makes no reference to black holes or any other gravitational source) through out all "empty space." and..."

I have been long aware that the magnitude of the the Casimir effect is dependent upon the presence of "near by" matter. (It was this fact that lead me and SpaceTiger to eventually agree to disagree, or simply drop, in our discussion about how long a micro black hole inside "solid" matter might live.)

VP calculations are basically the wave equation and of course its solution always depends upon the "boundary conditions." That is why I have been careful to always make the claims (like in a and b above) that the rate of VP production in "empty space" did not depend upon the presence or absence of a gravity field. (From some BH point source distant enough that during the lifetime of the VP violation of the conservation of energy, even light could not transit the distance between the point of VP production and the gravitational source. I.e. the source is far enough away to not be considered "near by" because it can not influence the VP event before it is over.)

What I now more consciously realize, and which forces some revision of (a) and (b) above, is that the geometry of the the calculation is also important. That is, the Casimir force between two flat condenser plates is different, at least slightly, from that between two curved plates, even if the gap between the two plates is the same in both cases. Thus, because space itself is curved at the EH and significantly somewhat beyond, then (b) above is not strictly true. How much it is changed, I do not know, but think it very unlikely to be many OOMs as is the "capture fraction" of single members of VPs near a small BH. (Much smaller fraction meet their normal fate of mutual annihilation). That is, I still claim that the primary reason why small black holes eat a much larger fraction of the VP pairs produced "from nothing" in violation of the conservation of energy, is due to the extreme gradient of the gravity field just outside the EH and has nothing to due with the energy stored in the field itself. - Again, my view is that the field is not "lending" energy for the production of the VP pair (IHMO, for reasons given in prior post) as LabGuy is suggesting it is.

I will, however, back off my prior claims that the the VP production rate is unchanged by the presence of a point singularity of mass (which is not "near by" in the sense defined above). It could be changed. The change is due to the curvature of space time, not stored energy that can be "borrowed." It is no doubt true that there is essentially an identity between this "space curvature" and "gravitational energy stored", so one could argue that it is the energy stored in the field which is producing any change in the VP production rate. I will grant that to LabGuy; however, I still contend that no "borrowing" of mass/energy is required to have VP production.

In fairness, I also want to note that LabGuy has expressed his doubts about the BH mass being all concentrated in at point source. Thus, for him, some of the mass of the BH may be "near by" (in the sense defined above) and thus avoid the "spooky" action at a distance. This possibility, is very much like my prior statement that if the mass of the BH extended all the way out to the EH and a little beyond, then I would not be so bothered by the "spooky" action at a distance that seems to be implied by the BH supplying the mass of the escaping member of the VP pair. I will also admit, that as a result of this exchange, which I am quite willing to drop now, I feel a little bit better about the local gravity field near the escaping member of the VP supplying the mass it has, but as that new particle is itself a source of gravitational field, I think it quite possible that near it the total energy stored in the gravitational field may have actually increased, instead of decreased to supply its rest mass and KE. I.e. still not completely satified that I have anything more than "empty words" to grab hold of. that is why I continue to hope someone will calculate the dependence of the "tunneling lifetime" of a BH against mass loss, and state its functional dependence upon mass. (To see if it is also "M cubed.") - See end of my post 38 and Chronos's post 35.

 

[Chronos]

Billy T, I don't think you caught the full implications of Labguys argument. I do, however, think you caught part of it. If you would suspend your disbelief for a minute, I think you would see his point - and it is a very good one. I was inclined to dismiss you as a hopeless crackpot before your last post. But now I think we might be able to redeem you - an easter thing. I like the way you think, just not the sequence.

 

[RoboSapien]

Stop living in wonder land, swallow the pill

http://www.wired.com/news/print/0,1294,35618,00.html

 

[Billy T]

Billy T, I don't think you caught the full implications of Labguys argument. I do, however, think you caught part of it. If you would suspend your disbelief for a minute, I think you would see his point - and it is a very good one. I was inclined to dismiss you as a hopeless crackpot before your last post. But now I think we might be able to redeem you - an easter thing. I like the way you think, just not the sequence.

Thanks. I appreciate any "evanglistic efforts" - I would like to "feel good" about believing, but currently do not (feel good about it - I do "believe" so can't "suspend disbelief")

 

[Billy T]

Stop living in wonder land, swallow the pill

http://www.wired.com/news/print/0,1294,35618,00.html

I visited ref. site. It has nothing to do with current discussion. If true that dark energy is steadly increasing the rate of expansion, it is "now" slightly more than twice the age of the universe (in light years) away I.e. slightly more distant than 28 billion light years away. Other than that minor error, seems interesting, but off subject.

 

[Billy T]

Mainly for Chronos:

I think a "crackpot" is one who is offering his own theory and contradicts the accepted view, especially if few arguments within the standard theory are presented. If you accept this definition, I am never a crackpot about physics - but some parts of the standard ontological interpretation of physics leave me cold. I think it best not to try to regard quantum mechanics as anything more than a fantastically successful predictor of experimental results. IMHO it is not making statements that humans can really understand about how the world is (ontological statements). QM is only giving a prescription for calculating results.

Even classical physics has some aspect that leave me cold. For example:

Consider a coil of 10 "primary turns" of AC current on a highly permeable circular iron (permalloy is better) ring with major diameter ten times the minor diameter. Assume the permeable ring is far from saturation - I.e. grant me that almost all of the magnet field remains inside the iron of the ring.

Now imagine a circular copper ring with the same major diameter as the iron ring is topographically linked to the iron ring (like two links in a chain). Furthermore imagine that the plane of copper ring is perpendicular to that of the iron ring and one part of the copper ring passes thru the center of the iron ring. (And conversely, one part of the iron ring passes thru the center of the copper ring.) It is also convenient, but not necessary, to assume that the copper ring was made from the same wire as the primary coil - same total resistance (ohms) so the impressed voltange and current in both secondary and primary have the same ratio.

There is essentially zero magnet field where there is any copper, yet the secondary loop (the copper ring) has current induced in it approximately 10 times greater than the primary current in the 10 turns!

Don't tell me any "empty words" about "magnetic lines of force" cutting thru the copper ring. Even Faraday, who invented the concept of "line of force/ field," knew they were not real, just a convenience to aid thinking. Remember, no part of the copper ever has any significant magnetic field near it!

Sometimes I don't even feel good about transformers! I think my problem is that I think too much about the words that are supposed to make me "feel good." I am especially trouble when two entirely different sets of "feel good" words are offered, as is the case with evaporating black holes. One of these sets of "feel good" words tells me that because of all the entropy the black hole has swallowed, the EH is very hot and radiating photons (mainly gamma rays) and this loss of energy/mass is why the BH is evaporating. The other set of "feel good" words says: No, it is the fact occasionally only one member of the VP pair is captured and the mass/energy of the new long-lived particle now existing in our observable universe must have been supplied by the BH as energy must be conserved.

Sometimes, these are several different ways to look at something. For example, there is a good discussion going on now in the "clasical physics" section thread: "Why do airplanes fly." (But these different view points are just different equivalent reformulations of the discriptive math.) In the case of BHs, it is hard to believe that gamma ray are the same thing as single VP pair members escaping.

Frankly I am surprized that that so many people do "feel good" despite these two entirely different "explanations," neither of which says anything about how the mass, all concentrated at the point singularity, is reduced. Both the escaping member of the VP pair and the gamma rays are born outside the EH. I.e. something happening at point "A" (the EH or a little beyound) is causing a change at point "B" (the singularity) and not a word has been said in either "explanation" as to how this "spooky" (to use Einstein's term) action at a distance is achieved!

But as I am even troubled by simple transformers, it is obviously me who is too easily bothered by "empty words." Perhaps I should also accept as an explanation of the effect of morphine: "Morphine makes you sleepy because it contains an narcoleptic agent." I believe both that small black holes do evaporate and that morphine does make you sleepy, but I want more mechanistic words to "feel good" about these facts I have accepted.

PS There is an "easter egg" hidden in the classical physics text above. Easter eggs" in text (as opposed to those in computer code) are plausible statements that are not true. I always give information which contradicts them - but one must think about waht they are reading to notice the contradiction. Many "eggs" are hidden in my book, Dark Visitor which you can read for free - send PM to know how.

 

[turbo]

Consider a coil of 10 "primary turns" of AC current on a highly permeable circular iron (permalloy is better) ring with major diameter ten times the minor diameter. Assume the permeable ring is far from saturation - I.e. grant me that almost all of the magnet field remains inside the iron of the ring.

Now imagine a circular copper ring with the same major diameter as the iron ring is topographically linked to the iron ring (like two links in a chain). Furthermore imagine that the plane of copper ring is perpendicular to that of the iron ring and one part of the copper ring passes thru the center of the iron ring. (And conversely, one part of the iron ring passes thru the center of the copper ring.) It is also convenient, but not necessary, to assume that the copper ring was made from the same wire as the primary coil - same total resistance (ohms) so the impressed voltange and current in both secondary and primary have the same ratio.

There is essentially zero magnet field where there is any copper, yet the secondary loop (the copper ring) has current induced in it approximately 10 times greater than the primary current in the 10 turns!

You have described an ideal 10:1 toroidal stepdown transformer, and yes, the secondary coil will have 10 times the current flow, but at 1/10th the potential. How is that disturbing? Do not be confused by the topology of the secondary coil - it is exactly equivalent to the topology of the primary coil, but there are fewer turns. This is how transformers work. You could have a primary coil with just a few turns and a secondary coil with ten times as many turns. This would be a step-up transformer, and the secondary would see 1/10th the current flow of the primary, but at 10 times the voltage. A laminate EI design (typical application) transformer works exactly the same way, but the topology is a bit different, and IIR, the traditional EI design is less prone to core saturation.

 

[Billy T]

You have described an ideal 10:1 toroidal stepdown transformer, and yes, the secondary coil will have 10 times the current flow, but at 1/10th the potential. How is that disturbing? Do not be confused by the topology of the secondary coil - it is exactly equivalent to the topology of the primary coil, but there are fewer turns. This is how transformers work.

Transformer I described is far from Ideal. If you read last paragraph of post 48, You will see that one of my statements (ten times the primary current in the single turn secondary is wrong. - It is the "Easter egg" I hid in the "classical physics text." When I put plausible, but false, statements in physics text, it is to encourage thinking while reading - I always give a statement that contradicts the false one. In this case, I noted that if the secondary was made for the same wire as the primary the ohms would be the same and thus the ratio of voltage to current would be the same (this not true either as there is reactance to consider but in any case it was a hint.) You have it different by factor of 100!

Well designed 10 to 1 turntranformers can step up the current by factor of 10, but mine is not well designed. If the secondary has too many ohms, as mine does, then the current will be less. You need to think more and "know less." I laid a trap for you and others who "know" a 10 to 1 transformer steps up the current by 10 and the voltage down to one tenth. A well designed 10 to 1 voltage step down transformer has much heavier copper wire in the secondary. If secondry wire is the same size as the primary wire, it will not yield 10 times the current. (assuming the primary wire is not much larger than it need be.)

But now to turn to the question of why I included this classic physics:
I wanted to cause people to see why I was not happy with "feel good" words (I at times call them "empty words" about how black hole loses mass.) by siting a classical example. Most people think that transformers work by magnetic flux lines cutting thru the secondary and they "feel good" about these "empty words" - Magnetic flux lines do not exist. By setting up a geometry where there is no magnetic field near the secondary, I wanted people to think about these "empty words" (in hope that when I point out that the two entirely different sets of empty words that "explain" black hole mass loss are also just "empty words" - they say nothing about the mechanism and even ignore the fact that in both cases (gamma ray radiation or VP particle escaping) the "cause" is at point "A" (outside the "event horizon") and the consequences is at point "B" the singularity where all the mass resides. I.e. this "action at a distance" needs to have some mechanism of connection, or I for one will continue to be unhappy.

I want to tell how transformers really work ( and admit that I am not really unhappy about them) While it is true that there need not be any magnetic field any where near the copper of the secondary turn, (and a Hall effect probe will show this for the case I set up) there is an electric field at the surface of the copper. Transformers work because the AC primary generates an electric AC field at the secondary. True the electric field is weaker when the secondary is far from the iron ring, as in my designe, but the intergral around the ring of this field is what drives the current. If you were to cut the secondary to make a gap, you would of course have no secondary current but see the fully voltage induced across the gap.

Summary: no need for magnetic field near secondary turn or "feel good words" about flux lines cutting the secondary. The primary makes and electric field and it is this field, not a magnetic one, that makes the secondary current flow. Your post reflects the common view of one who has not thought about the way transformers really work.