First Stars - How big - Now Black Holes?

In summary: The first stars were much denser than stars today. They left behind black holes when they died. The universe expanded while the first stars ran their life cycle. The typical star pair of the second generation also left 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?I think that a review of the following sites would probably answer all questions at least to
  • #36
Billy T said:
(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.
 
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  • #37
turbo-1 said:
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.
 
  • #38
Chronos said:
...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.
 
  • #39
SpaceTiger said:
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.)
 
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  • #40
turbo-1 said:
...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.
 
  • #41
Billy T said:
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.. :yuck:
 
  • #42
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.

Labguy said:
...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" )
 
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  • #43
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.
 
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  • #44
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.
 
  • #45
Stop living in wonder land, swallow the pill

http://www.wired.com/news/print/0,1294,35618,00.html
 
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  • #46
Chronos said:
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")
 
  • #47
RoboSapien said:
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.
 
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  • #48
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.
 
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  • #49
Billy T said:
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.
 
  • #50
turbo-1 said:
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.
 
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  • #52
Well Billy, you ambushed me with a "naive" question, and when I gave you a simplistic idealized answer you jumped ugly on me to demonstrate your "superior knowledge". That's a cheap trick, kinda "junior high" if you get my drift. I was trying to help you, and you bit my hand. Now, you tell Labguy in this thread that you don't even recognize your own words.

https://www.physicsforums.com/showthread.php?t=69077

Maybe a quote from your page will help you remember, Mr. William J.Beaty EE. Just curiosity, does the "T" in Billy T stand for "Tesla"?

Billy B said:
I've always had a niggling suspicion that toroidial transformers are far more weird than anyone suspects. If we wind ourselves a toroidial (donut) inductor and plug it into a 120VAC wall plug, the device will draw a current but ideally won't draw any flow of energy. However, if we then wind a big loose 1-turn secondary "coil" around the donut (through its hole) and short out this "coil", a huge amperage appears in the wire, the coil grows red hot, and many hundreds of watts are drawn from the donut inductor and from the wall outlet. Even if the 1-turn secondary is lifted significantly away from the coil, it still heats up.

Why is this weird? After all, it's just the way that normal transformers work. But think for a moment. In donut-inductors, the magnetic field-lines from each turn of wire extend over to the area enclosed by the next turn of wire, and as a result the magnetic field connects in a circle, and no field extends past the surface of the donut. Yet the secondary coil is entirely *outside* the donut, and therefor the magnetic flux never touches it. We can even use a large, narrow toroid (a hoop-like primary coil) and wind a floppy secondary over it so that the turns of the secondary coil remain many inches away from the wires of the primary and many inches away from the magnetic flux it encloses. The question arises: how does the magnetic field inside the donut-inductor create a current in the secondary coil if no magnetic flux comes anywhere near the the secondary coil? Electronics students always ask this question. The answer in the past has always been that it is simply a law of physics and a part of Maxwell's equations.

My suspicion that the above effect might hide profound mysteries is greatly amplified by the fact that mainstream scientists aren't intrigued by this effect. They essentially have unilaterally DECLARED IT TO BE UNINTERESTING. This is a strange position for a scientist to take. If something is strange and not quite explicable, wouldn't it stimulate their curiousity? Instead it does the opposite! I'm very aware that similar situations are very common throughout modern science. It's a sort of hidden sickness that penetrates every facet of science, and twists science into something that is entirely different than what scientists believe it to be.
Please grow up or have a nice day :smile: somewhere else.

BTW, don't bother emailing me. You are blocked. :cry:
 
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  • #53
turbo-1 said:
I'll bet you're popular at parties, Billy...
I am sorry if I offended or embarrassed you. Most people (at least 80%) who know a little about transformers tend to think that the current in the secondary has something to do with “line of flux cutting thru the conductor” etc. but as these lines do not exist, these “explanations” are just “empty words.”

Transformers work almost the same way light propagates. - an AC magnetic field creates an AC electric field, which in turns creates an AC magnetic field. In the transformer case, this second magnetic field opposes the first and makes the primary draw more current to maintain the first magnetic field. In the case of light, it is a little different. The collapsing magnetic field still creates the orthogonal rising electric field but when it collapses, the electric field drives the “displacement current” - a term that Maxwell added to the set of already known equations about electricity and magnetism. (That was his great contribution.) It is called a “current” because it plays the same role as a moving charge - I. E. it can and does make a magnetic field.

IMHO, there are many “empty words” published every month about “heaven” “souls” “angels” “spirits” etc, but I don’t care much about religion and they do make a lot of people “feel good” so generally I say nothing about this. (I am an agnostic, lacking the conviction, or ego, to be an atheist.)

I do however care about physics. When I read “empty words” in this area I tend to speak up. I may be abrasive and surely it was not nice to set a trap for exposing some “empty words” that most people, not just you, believe in and do feel good about. (“flux lines” helping you to “understand” transformers)

Because I may not be as smooth as I could be, I do offend and get reactions, like being called a “crackpot.” None the less, I will continue to question the validity of “empty words.” I am especially bothered when two entirely different sets of “empty words” are offered to “explain” the same physics!

Specifically in the case of small black hole, BH, evaporating (which I believe to be their true behavior):
(1) Some people will explain the mass loss as due to the entropy it has swallowed making the event horizon, EH, so hot that the (essentially) black body radiation from it is peaked in the gamma ray part of the spectrum.
(2) Other people explain the mass loss by the occasional capture of only one member of a virtual particle pair in the intense gravity gradient of a BH which prevents the normal mutual annihilation.

These two different “explanations” conflict with each other, at lease in how the mass/energy is stored in our observable universe (photons or particles?).

Both “explanations” add mass/energy to our observable universe, at some point outside the EH. Both produce a mass loss at the singularity of the BH. Neither “explanation” says anything about how this “action at a distance” is achieved.

In view of these facts, which I think all agree to, is it fair to be derided as a “crackpot” for pointing out the conflict and inadequacy of the “explanations”? Physics, unlike religion, is too important to me not to comment on this.

I have repeatedly stated that I am willing to accept the consequences of the math that shows that small BHs do “evaporate” just as the math of quantum mechanics predicts quantum entanglement. That is, there are things in physics that no human is ever gong to really understand; but I refuse to claim I do, because of two sets of conflicting “explanations.” I prefer to honestly admit that some things in physics are just beyond human understanding. I.e. we will never “feel good” about what the math is telling us.
 
  • #54
turbo-1 said:
Now, you tell Labguy in this thread that you don't even recognize your own words.

As far as the text you reproduced "as mine" in your post 52, please note it is by Billy B and I am Billy T - I do not recoginze it as mine. I will and have admitted to holding views about visual perception in conflict with most cognitive scientists and offering my own theory - this qualifies me as a "crackpot" in this area, but not in physics, where I tow the standard line, and taught it.

I also want to note that the second sentence of that quote in your post 52, which you think is by me, is simply wrong. I would never say something so stupid. I was part of the team that designed magnetic hysteresis damping rods to use the Earth's magnetic field to slowly and passively take energy out of oscillations in satellites (in case more active means failed).

Only 99.99% of "crackpots" are wrong - that 0.01% is where all our progress comes from. I do offer three independant proofs that the standard view of perception is wrong. Recently there is accumulating evidence that in parietal tissue there is predictive activity, just as I predicted more than 10 years ago in a paper I published. This predictive activity is of course still interpreted in terms of the standard paradigm, not in my "shifted paradigm" and even the fact that it is predictive is barely mentioned. See for example:


The Journal of Neuroscience, July 16, 2003, 23(15):6209-6214
Gaze-Centered Updating of Visual Space in Human Parietal Cortex

W. Pieter Medendorp, Herbert C. Goltz, Tutis Vilis, and J. Douglas Crawford

Abstract
Single-unit recordings have identified a region in the posterior parietal cortex (PPC) of the monkey that represents and updates visual space in a gaze-centered frame. Here, using event-related functional magnetic resonance imaging, we identified an analogous bilateral region in the human PPC that shows contralateral topography for memory-guided eye movements and arm movements. Furthermore, when eye movements reversed the remembered horizontal target location relative to the gaze fixation point, this PPC region exchanged activity across the two cortical lobules. This shows that the human PPC dynamically updates the spatial goals for action in a gaze-centered frame.


turbo-1 said:
Well Billy, you ambushed me with a "naive" question, and when I gave you a simplistic idealized answer you jumped ugly on me to demonstrate your "superior knowledge". That's a cheap trick, kinda "junior high" if you get my drift. I was trying to help you, and you bit my hand.
Again let me say I am sorry. (Probably does no good as you have baned me from your listings, but perhaps someone will tell you.) I was not trying to show "superior knowledge" - there are many here that know more than I do. I was only trying to show that "empty words" are often accepted as explanations, even in classical physics. Also trying to show this was my statement that some doctors (MDs) give about how morphine works. One must alway be on guard against "empty words" that sound like they explain something.(I probably offended some doctors also.)
 
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  • #55
I yield, Billy T, and retreat to my initial impression. You are a pottery magician.
 
  • #56
Chronos said:
I yield, Billy T, and retreat to my initial impression. You are a pottery magician.
What the H... is a "pottery magician" - I don't know if I should thank you, object and try to defend, or just ignore. :rolleyes:

More seriously, I am trying, in my unfortunately sometimes offensive way, to help people be more cautious about the words they accept as "explanations." (Morphine does not make you sleepy because it contains a narcoleptic agent. - It works, if i remember correctly, because it has approximately the same molecular shape as the neurotransmitter seritona and thus binds to its natural receptor sites - don't rely on this information. I give it only to show what a real explanation would involve.)

I am truly sorry if I offended anyone by showing (with the toroidal transformer example of a secondary in a region of space where no magnetic field ever exists), that even in "classical physics" four out of five physics students entering more advanced physics classes I once taught thought the secondary current was caused by "magnetic flux lines cutting thru the secondary coil."
 

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