Supernova From Experimentation At Fermilab

Discussion in 'Astronomy, Exobiology, & Cosmology' started by Paul W. Dixon, Feb 28, 2001.

  1. AlphaNumeric Fully ionized Registered Senior Member

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    I've yet to see him do any and I've given him plenty of opportunities. Like when he claimed Hawking radiation can tunnel material into the black hole. I asked him to explain how it can do precisely the opposite of what Hawking and everyone else (including Malcolm Perry, who Paul mentions a lot and who lectured me Hawking radiation, which Hawking developed around the time Perry was his PhD student!) says. Nothing. Even when he claims something as innocuous as just percentages, I have asked him to back them up and he cannot. So where's he demonstrating working knowledge of physics? :shrug:
    Can you back that 'a week' ballpark figure? You'll find it depends on the number and size of the extra dimensions. But I'll give you a chance to show you can produce a backup to your claim of 'a week', just like I gave Walter a chance.
    But if the black holes are stable, they would form a gas throughout the universe which has a Boltzmann distribution and then there'd be some moving slowly, enough to be gravitationally captured, in the vicinity of any and all large stellar objects. Yet we've been here longer than 'a week'.
    Conversely, we have to make some pretty specific assumptions about quantum mechanics and gravity to firstly say that there's a change black holes can form even within 10 orders of magnitude of the LHC's energy levels. More specific assumptions about Hawking radiation being wrong. More assumptions to get the Earth eating time down to less than 4 billion years (at which point the Sun will die anyway). And even then, we've had to take the semiclassical limit of our understanding of quantum gravity (such as using SuGRA to model the low energy limit of string models, something I do my PhD on).

    So the "We're doomed!" people are making more assumptions about the danger than we are!
    Can you point me to a post where Walter provides a level of understanding which goes in excess of someone whose read a few pop science books and Wikipedia? The link you provide where he corrects you doesn't go very far.

    For instance, I linked to the lecture notes I transcribed from the lecture course by Malcolm Perry I attended and then asked Walter to provide a back up to his claims on Hawking radiation which was of similar technical detail to the lecture notes I'd provided. After all, if someone as wet behind the ears as myself could understand those lecture notes, and get a Distinction in their 4th year exam on it, then Walter should have no problem giving a response which shows a similar level of technical understanding, right? Right?

    And having read through your post 1524 I fail to see anything which isn't addressed in the safety argument. You just arm wave, assuming that a black hole made will repeatedly destroy the Earth or it only needs to hit one particle to be trapped or the process of absorbing material is quick or that a lot of them will be made. The safety analysis goes through such things quantitatively and precisely, you just blur the specifics enough that you always end up at the end you assume, that there'll be a clear and present danger.
    Actually, Coulomb scattering is more appropriate. They aren't referring to electromagnetic scattering, they explicitly state they are considering neutral black holes and gravity only interactions. Since all the particles involved in the interactions have gravitational interactions with one another, you wouldn't model them as Compton scattering, where they are blind to one another until collision, but as them interacting with one another as they approach, via gravity. The diagram on the Rutherford/Coulomb Scattering page of Wikipedia shows how such scattering looks diagrammatically, which is the kind of interaction two objects interacting gravitationally would have. Infact, it's the same kind of process the lecture notes I liked to discuss, when working out the absorption cross section of a black hole. It's a pretty standard form of interaction in general relativity. Heck, I even wrote a program in C, for my 3rd year computing project, which worked out, via limiting orbits and numerical solutions of the Einstein Field Equations, the absorption cross section for a black hole absorbing photons or massive particles.

    So it would seem your loud mouth whining about what (even if you were right) is nothing but a matter of terminology is actually demonstrating your ignorant of general relativity and basic gravitational interactions.

    Good job.

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  3. Reiku Banned Banned

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  5. Reiku Banned Banned

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    I don't think that was his point AN?
     
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  7. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    That is correct if there has been long enough time for thermal equilibrium distribution to be established. The rate at which a collection of particles moving with essentially the speed of light will relax into a thermal distribution depends upon their collision rate and how much energy can be exchanged in the typical collision. We are considering very tiny black hole in a very large universe. I will not do the calculation (I am lazy) but guess that in order for two of these relativistic extremely tiny black holes to exchange more than 1% of their average energy (one becoming more and the other less massive while both are still highly relativistic, V ~ C still for both after the collisions) then the impact parameter is probably less than the Bohr radius. - I.e. to even make a start at establishing a thermal distribution via the gravitational collision the two tiny relativistic black holes must pass each other approximately one hydrogen atom apart. How often do you think that occurs in the vastness of the universe? Do you think the typical black hole has even had one collision in which 1% of the energy has been exchanged? I do not, based on both my guess and the safety report's own analysis that the tiny black hole EVEN traveling inside the Solid Earth would very rarely come close to any nucleus to gravitationally slow down in the life time of the sun.

    You are falsely assuming that they would have established a Boltzmann distribution by gravitational scattering in the vastness of the universe where as even the safety report concludes that they would not even significantly slow down, even while oscillating INSIDE THE EARTH FOR A SOLAR LIFE TIME. Do you feel a little silly? If not why not?

    No I am not assuming any of this in post 1524 (or elsewhere). In fact in post 1524 I specifically state that I think it unlikely there is any danger. What I do there is to list three requirements for there to be any danger. Discuss them a little and conclude that the second and third are likely to be met so the eggs are mainly in the first basket - namely that Hawkins’s "final flash" making the tiny black hole existence end must be true for Earth to be safe. I then note that the final flash is just the continued extension rate of radiation loss down to the zero mass end, while assuming that Quantum Effects do not apply. Thus it is you and the people assuring us that the tiny black hole will rapidly disappear by Hawkins radiation who are assuming something - namely you are assuming that these very tiny objects are an exception in the small scale world - they are much smaller (the EH radius) than the atoms where quantum effect dominate. I admit that I have difficulty in making YOUR assumption that quantum effect do not apply to these object with scale where the quantum effects normally are completely the dominate physics.

    In post 1556, I note that while I am not comfortable making the assumption that quantum effects can be ignored on the tiny scale where they are dominate, I do think the tiny black hole probably is not stable (but I am not sure) because on that subatomic scale there is no arrow to time - every process is reversible. I illustrate that with E ---> B Energy makes black hole, implies that B ---> E with the same probability and rates. Or still in other words: There are no "one-way" trap doors on the sub atomic scale.

    To offer a suggestion as to how B ---> E might be possible I do suggest that a quantum effects may be how B ---> E can occur - namely quantum tunneling is possibly how the quarks (or whatever made the mass singularity)can escape to the universe outside its EH.


    I have only skimmed it, but perhaps you can tell me which of the 97 pages discusses my main concerns posted in 1524. I would like to know where they calculate (or even discuss) the rate at which a tiny stable neutral black hole becomes charged. I point out that it will pass thru "zillions" of electronic orbital wave functions (probably in every meter of it travel thru the Earth) I know that electrons can be spatially distributed (as they are in these permitted orbitals) or very localized in space (as they are in the photographic film crystals - much smaller that the crystal forming what is called a "color center" sometimes") I.e. the electron has the ability to go thru multiple paths as a wave and also the ability to be like a tiny point charge. As you surely know the probably a specially distributed electron will "localize" is proportional to the square of psi. I suggested the only an extremely small fraction of unity (the integral of psi^2 over all space) is inside the EH of the tiny black hole passing thru some particular electronic wave function of an orbital, but this happens "zillions of times" so I did guess that the stable neutral black hole passing thru the solid Earth would become charged without traveling any significant distance thru the dense core. Where do they discuss the scattering of a charged black hole by a charged nucleus? What page?

    I completely agree that if we limit the interactions to only the gravity of such a tiny mass that nothing to worry about will happen in the life time of the sun. However to ignore the true Coulomb interaction (made easier to do by calling the gravitational interaction a Coulomb interaction) is at best very misleading if not a dishonest straw horse set up to knock down, while ignoring the possibly important interaction, which surely is at least
    100,000,000,000,000,000,000,000, 000,000,000, 000,000,000 times stronger that the gravitational one they do consider and call a "Coulomb" slowing down of the black hole. (Feel free to add some more zeros if I do not have enough. I seem to recal that the electric force between a single electron and a proton separated by a Bohr radius is greater than a locomotive can make. Whereas the gravitational force beteen the proton and this tiny black hole is trillions of times smaller that a flea's weight - but you get the point I hope.)

    I will not defend my guess of the time scale of a week for a stable charged Earth bound (less than escape velocity) tiny black hole to eat the Earth. Perhaps it is a day, perhaps it is a year. Who cares? The point is that it is not longer than the sun will last. I will tell my thought processes that lead me to suggest a week:

    The orbital period of an object in a gravitational field does not depend upon the orbit eccentricity - only the semi-major axis. The low Earth orbit period is approximatel1.5 hours. Thus if the Earth's interior not a thin shell were to be concentrated at the center of mass, that shell would collapse towards and hit the center of mass in about 90/4 minutes certainly less than 30 minutes. So the process of "eating" the last 3/4 of the Earth's mass will certainly take less than an hour. I also noted that even if the tiny black hole could make a void the size of a pea at the mass center of the Earth, one would not need to postulate that a pea mass black hole's gravity is "pulling the Earth" into it. Even if the tiny black hole had zero gravity but could just maintain a pea sized void (matter simply ceased to exist as it crossed the surface of the pea void) the plastic flow of the Earth under its own gravity would rapidly more mass into the pea sized void. Thus in few hours at most, 99.9999999+% of the Earth would be eaten by a very tiny black hole, even ignoring the fact it would have some gravitational attraction force on the Earth outside its EH. So the time scale is really mainly how long does it take for the tiny black hole to lose energy by Coulomb scattering in the dense solid Earth and sink to occupy the Center of Mass point (or a spot within a few miles of that point) of the Earth's mass? Once it is sitting near there the Earth will just plastic flow to the black hole and become part of its mass.

    I think that a week is a reasonable upper limit guess as to how long it could take "zillions" of Coulomb scattering to bring the tiny black hole to rest near the Earth's CoM. If you want to0 guess a year or two, instead of a week - that is ok with me.
    POINT IS All will die when it does a few hours later.

    Please note NEVER when I have said "Coulomb" did I refer to a gravitational attraction as the safety report authors ALWAYS do.

    I will not enter into your pissing contest with Walter. (He does not seem very willing to either.) I will just remark that not only has he been able to correct me, but also he has not made any gross errors like your above assumption that the tiny black hole lost in the universe have a now have a Boltzmann distribution. Hell the universe is so vast that even if they could inter act with each other via the Coulomb force they would not have a Boltzmann distribution. – Want proof?

    Well the intergalactic hydrogen is mainly ionized even though most of it is extremely cold. I.e. it is mainly ionized plasma because when an harsh UV photon does ionize a neutral atom of hydrogen, the electron has very low probability of getting close enough in the vastness of space to a proton to recombine with it via a cascade of radiation down thru the energy levels. If you want to see this mathematically, look up the Saha Equation and grind it thru. (With the low density of hydrogen in the universe, of courses. Use 100K for the temperature and you will still get it as mostly plasma! SPACE is VERY BIG. Your black holes are 99% still relativistic, not Boltzman distributed.
     
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  8. AlphaNumeric Fully ionized Registered Senior Member

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    So can you or can you not produce a justification for your 'one week' claim? It's hardly a pissing contest for you to justify the figure you come up with and repeat many times and which contradicts published papers on the matter, who go into detailed calculations about how the 'time to destruction' is a function of number of extra dimensions and their sizes. And it's hardly a pissing contest when I ask Walter to back up similar statements he's made.

    Your justification is entirely arm waving. You don't even do rough 'back of an envelope' order of magnitude calculations. Can you please do that for me, it'd have taken you about an extra 3 minutes in composing your post.

    And you utterly failed to retort my comments on the difference between Coulomb and Compton scattering. The report says it's a Coulomb like scattering. The particles see one another over large distances and so you have to consider their interactions as they come in 'from infinity'. Compton scattering doesn't need that. And so when considering qualitative terminology, the concepts of Coulomb scattering are much more appropriate than Compton scattering. You talk about me making 'gross errors' and yet you don't even seem to understand broad conceptual notions like that.

    Also, Walter has made 'gross errors', such as claiming that Hawking radiation tunnels material in as well as out of the black hole. I gave an explanation why that was incorrect, commenting on how there isn't an isotropy in the system because the \(g_{tt}\) component of the metric has a preference to emit material, not absorb it, via quantum processes. I asked Walter to provide a derivation of his claims which was more than simply repeating his argument in a qualitative way, on a level comparable, quantitatively, with my lecture notes on black holes (so he can prove he's at least up to the level of 1st year PhD students) but despite repeated requests and what is now many months of time, nothing.

    I asked you to point me to a single post of his where he shows working knowledge of quantitative black hole mechanics. All his post you linked to did was give qualitative information. When I was 17 I wrote a 4 page description of black holes, off the top of my head in class, discussing Hawking radiation, entropy and quantum tunneling which displayed a similar or more advanced level of understanding than Walter did in that post. Looking back, about 7 years (6 of which have been doing theoretical physics and applied mathematics at top universities) later and knowing what I know now, could I 'understand' black holes back then? Not on your life. If anyone said "Can you show me how that result came about?" or "Can you justify that with a derivation?" I'd have instantly admitted "No, but I plan on learning that in the next few years" and now I do know it. People like Walter and Paul have been whining about this stuff for literally decades and they haven't shown an increasing level of understanding. In the 2 years I've crossed paths with Walter over on PhysOrg I've learnt about the compact dimensions in string theory, various levels of description of them and even come up with my own result in them which I will publish very shortly. What's Paul managed to do? Claim he's been nominated for the Nobel Prize in physics but has never been published in physics and Walter's spent some time editing Wikipedia's page on magnetic monopoles to claim he found one, which is then removed because it's unsubstantiated and considered unjustified 'original research'. That's time well spent!

    Has Walter, in the last 5 years, been publishing in reputable journals analysis of the LHC and it's possible dangers? Or has he just been saying "The analysis is wrong" when someone else provides him with their analysis? What about Paul? In the last 5 years I've got evidence I've learnt a lot and achieved plenty. I am now more qualified in physics than Walter or Paul. Is that me 'pissing' or is it a statement of fact? What is Walter doing, right now, to actively expand his knowledge of physics and maths? Where did he learn his working knowledge of PhD (and beyond) relativity? Certainly not with a minor in Physics and working at a botanical garden in Hawaii.

    I'm asking questions which, if they aren't lying, or 'sugaring the truth, they should have no problems answering. But they do seem to have trouble answering. Remember, they are the ones going to court over this or picketing the front of the facilities. They want their voices to be heard but when someone says "Hang on a sec, rather than us providing things for you to say "Wrong!" to, why you don't provide things you consider "Right!" and we'll look at it?" they go suddenly silent. Paul has gone from engaging in discussion in this thread to nothing but a posting robot. Has he become senile or just unable to support his discussion? Walter, despite wanting to take a multinational, multibillion dollar group of some of the cleverest people alive to court, doesn't want to provide any evidence to back up his claims which aren't "So it's not 100% safe then?".

    What am I to think when they cannot even get past questions from a lowly PhD student like me? John Ellis, who is a personal friend of my supervisor and considered one of the greatest physicists alive (and I'm gutted I didn't meet when he was at my department a few months back!), have infinitely better understanding and nimble, efficient, logic than me so if you cannot retort what I'm asking on a forum, where you have tons of time and the internet at your fingertips, Walter is going to get pasted in a court when he's put on the spot and cannot do anything but say "I deny your work!" and produces none of his own.

    He wanted a pissing contest and how he's found he's not up to the challenge.
     
  9. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I am basically just going to ignore you because you exposed your ignorance, as I pointed out in post 1564, in making the GROSS ERROR of assuming the Boltzmann distribution, but I will note that, contrary to the words you are putting in my mouth here, I agree with these published results about how long the GRAVITATIONAL interaction would take to slow down the tiny black hole.

    You do not seem capable of understanding my point, which is:

    That the tiny black hole if stable and bound inside the Earth, (i.e. has less than the escape velocity - highly likely for all that are produced by colliding beams) will pass thru "zillions" of the orbitals of electrons in a few meters at most of travel in the dense matter of the Earth's interior and in each pass thru this "electron cloud" there is a very small, but not zero, chance* that the electron will become "localized" inside the tiny black hole and then it is charged and interacts at least 100,000,000,000,000,000,000,000,000,000,000,000,000 more strongly via Coulomb forces that it does via gravity forces (Which the safety report miss leading calls a Coulomb interaction.) Surely they know that the Coulomb force is much more effective at slowing the tiny black hole down than the gravitational force is. (Probably I need to add dozens of more zeros in the crude estimate above of the ratio of these two forces as the tiny black hole has much smaller mass than a proton.)

    Thus no one should be impressed, as you appear to be, by the fact that gravity as a slowing force (even if miss-leadingly called "Coulomb") is not worth even thinking about. The safety report needs to consider the much stronger Coulomb force slowing the tiny black hole down.


    ------------------
    *One can roughly estimate the instantaneous probability of the electron becoming localized (particle like) as the integral of psi^2 over the very tiny volume inside the event horizon of the tiny black hole at the current point on its trajectory thru the electron orbital. I will designate the results of that volumetric integration as: p(x,l,o) where "x" is the current location along the trajectory line "l" and "o" is the particular bound orbital's spatial distribution. 1>>>> p(x,l,o) and of course I have assumed, as is normally done, that psi^2 is "normalized" so that the integral of psi^2 over all space is unity.

    Now to get the probably that the electron is localized inside the EH during the transit along the particular trajectory line "l" one must integrate p(x,l,o) over x. In principle this is from minus infinity to plus infinity, but as the integrand (psi^2) is only greater than 0.0001 over a distance much less than the Bohr radius, the range of the integration is very small. I will designate the results of this line integration as P(l,o).

    Now one must integrate P(l,o) over all possible trajectory lines. I will designate the result of this integration as P(o).

    Now one must integrate P(o) over all of the orbitals of a particular atom or molecule. I will designate the results of this integration as P(a) where "a" designates the particular atom or molecule. For example integrate over all 26 different orbitals of an iron atom or over all the 28 different oribitals of a NaCl molecule or the 11 different orbital of Na and the 17 of Cl when they are not unitied as NaCL. With just these three elements, and not even mentioning iron cloride or more than 10,000 other complounds, there are 26+28+11+17 = 82 different integrations to do. When all componds are considered, you are asking me to do about 100,000 integrations in "three minutes," just for this one stage of the process associated with the capture of the first electron only! (Once it is charged, we need repeat everything again, but now for both capture of a second electron or the neuralization by capture of a proton.)

    To avoid confusion earlier, I did not make explict that the integration over the orbitals was actually a function of the atom or molecule the tiny black hole was currently passing thru.

    Now we must integrate P(a) over X, the coordinate variable along the distance the tiny black hole travels in a "one way" pass thru part (or all) of the solid Earth. This integral will of course require Da(X), the density of atoms (or molecules) of type "a" along the path thru the solid Earth. (I neglect the fact that the tiny black hole which flies thru the atmosphere but being with less than escape velocity returns to plunge back thru the Earth again could actually become charged during the passage thru the atmosphere as I want the range of X to be defined well as the diameter of the solid Earth.)

    There is still another integration to do as the velocity of the tiny black hole will be important also. (Slow ones will have more time in any small part of their trajectory "dx" along the trajectory line "l" to localize the electron from the wave form of the orbital to the particle bound inside the tiny black hole.)

    I thank you for having such a high opinion of my skills that you state that I could do all these integrations and had at my finger tips, the spatial distribution of all the orbitals of all the atoms and molecules in the interior of the Earth along with their density function, Da(X), in "three minutes more" but either you greatly overestimate my knowledge and skills or you do not have the slightest understanding of the complexity of the problem.

    That later alternative must be why you fault me for only making a guess that it is about "one week." I did tell you how I arrived at that guess in prior post 1564. For your convenience, I have edited post 1564 to make that section green, like you see here..


    SUMMARY:
    You do not have a clue about what is required to do this calculation you asked me to do in "three minutes".


    If I am mistaken about this, perhaps you will show me how it is done, but I am more generous: I will allow you three days to complete a meaningful "back of the envelope" calculation of the rate at which the tiny black hole becomes charged with its first electron.

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  10. Reiku Banned Banned

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    '' ''Has Walter, in the last 5 years, been publishing in reputable journals analysis of the LHC and it's possible dangers? Or has he just been saying "The analysis is wrong" when someone else provides him with their analysis? What about Paul? In the last 5 years I've got evidence I've learnt a lot and achieved plenty. I am now more qualified in physics than Walter or Paul. Is that me 'pissing' or is it a statement of fact? What is Walter doing, right now, to actively expand his knowledge of physics and maths? Where did he learn his working knowledge of PhD (and beyond) relativity? Certainly not with a minor in Physics and working at a botanical garden in Hawaii.

    I'm asking questions which, if they aren't lying, or 'sugaring the truth, they should have no problems answering. But they do seem to have trouble answering. Remember, they are the ones going to court over this or picketing the front of the facilities. They want their voices to be heard but when someone says "Hang on a sec, rather than us providing things for you to say "Wrong!" to, why you don't provide things you consider "Right!" and we'll look at it?" they go suddenly silent. Paul has gone from engaging in discussion in this thread to nothing but a posting robot. Has he become senile or just unable to support his discussion? Walter, despite wanting to take a multinational, multibillion dollar group of some of the cleverest people alive to court, doesn't want to provide any evidence to back up his claims which aren't "So it's not 100% safe then?". ''

    > Jesus Alphanumeric, do you want some salt with that. Is that you? Have you slagged them off enough?
     
  11. AlphaNumeric Fully ionized Registered Senior Member

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    They have produced all over the universe, for 13 billion years in all directions, at all relative momenta. Such particle groups have thermal or kinetic distributions which are Boltzmann in nature.

    And you'll find that people like Lubos Motl have made mention of this line of reasoning too. And he's 100 times the physicist I am, which is a trillion times the physicist you are.
    You do realise that 'A Coulomb-like interaction' is a general name for two objects whose interaction extends over an infinite distance, right? While a Compton one involves them having no interaction other than direct collision.

    Two electrons constantly exchange photons. Two objects with mass constantly interact gravitational. Hence 'Coulomb like'.

    A high momentum photon and an electron don't see one another till the photon hits the electron. Hence not Coulomb like.

    Simply repeating your ignorance doesn't make it suddenly correct.

    Besides, right now there are trillions of neutrinos streaming through your body and then through the Earth and out the other side. In 100,000 tons of water about 6 will interact a day with the water. Despite trillions of trillions of trillions passing through the water in that time. A beam of neutrinos can pass through 30,000 LIGHT YEARS of solid lead and still 50% will come out the other side!

    Black holes of the mass being banned about in these discussions are even less interactive than that. How many oscillations back and fore through the Earth would a black hole moving at 10km/s (at the centre, it slows to a stop and then falls back in) need to do to travel 30,000 light years. No, seriously. Tell me. Work it out.
    Orders of magnitude I said.

    For instance, the mass of the Earth is 6 trillion trillion kg (I know this off the top of my head) = \(6 \times 10^{24}\). Radius, assuming a sphere, is 6400km = 6,400,000 metres = \(6.4 \times 10^{6}\). Volume = \(\frac{4\piR^{3}}{3}\). Assume a constant density, so you have that \(\rho = \frac{M}{V} = \frac{3 \times 6 \times 10^{24}}{4 \pi \times 6.4^{3} \times 10^{18}\). Orders of magnitude gives that this goes to around \(\rho \sim \frac{1}{4 \times 6^{2}} \times 10^{6}\), which is about \(\frac{10^{4}}{1.5} \sim 6.6 \times 10^{3}\). So the rough average density of the Earth is 6.6 tons per cubic metres. Wikipedia informs me it's 5.5. Not bad, within 20%, which is pretty decent for an order of magnitude approximation. If I was out by a factor of 10 in either direction (ie an order of magnitude) I'd have done something pretty wrong, but I was out by a factor of 1.2.
    See how simple it is? Now you can work out the cross sectional area of a nucleus, which is the largest, easiest, thing to hit in an atom and then see how likely it is, yadda yadda yadda. I didn't even need an actual envelope for that one!

    And don't try to turn this around on me. I asked you to backup your numbers. You're doing as Walter does, you cannot do the numbers yourself so you try to get someone else to do it, at which point you'll just say "Wrong, I disagree!" if they don't back you up.

    I've shown you I know how to go about it. Now I want you to finish it. It's your claim. I've demonstrated I do know the first thing about computing such things. Remember I also linked you to a set of black hole lecture notes which describe computing absorption cross sections. I got a distinction in that course. So Cambridge professors think I have demonstrated I know the first thing about black holes too. I also wrote that program in C which does this all numerically too. I'm fairly sure I've got it somewhere.

    Where's the evidence you can compute anything like that? I've given you the general method, now it's your turn to put your physics where your mouth is.
     
  12. Reiku Banned Banned

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    ''And you'll find that people like Lubos Motl have made mention of this line of reasoning too. And he's 100 times the physicist I am, which is a trillion times the physicist you are.''

    It's like a mental problem with you isn't it Alphanumeric. You just can't hold yourself back from digging in a sly insult?
     
  13. AlphaNumeric Fully ionized Registered Senior Member

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    No, 'AlphaNumeric' will do just fine thanks, I don't need to be canonised just yet.
    And you couldn't reply to anything I posted other than to just insult me. Nice hypocrisy there.

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  14. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    For reasons already stated, I am ignoring you, but I do not ignore pure nonsense. Gravity is NOT a Coulomb OR "Coulomb like" force. Gravity is one of the four distinct forces of nature, the Coulomb force is another, both extend to infinity with inverse square law fall off in strength.*

    A dog is a "horse-like" creature as both have four legs is an equally silly statement.
    --------------------
    *There are a few physicist who think on a very large scale gravity is falling off slightly faster as that could explain the acceleration of the expansion of the universe instead of making an appeal to "dark energy".

    False and more nonsense. That is called Compton scattering, but usually it is a high Z nucleus that causes significant scattering angles. If an electron is the scattering center, instead of a high Z nucleus, then much of the original momentum is transferred to the recoiling electron. The photon would be red shifted and only slightly scattered, but it would still be Compton scattering.

    No, more nonsense. Rudford showed (when discovering that the nucleus is very tiny compared to the atom) it is not the largest thing the tiny black hole will "hit." It will pass THRU "zillions" of electron orbitals on average before its tiny Event Horizon has even one nucleus inside it’s EH. You still do not understand that the important problem is not the cross section of the nucleus for gravitational capture slow down but the tiny black hole becoming charged and then using the much stronger electric Coulomb force, instead of the very weak gravity force to grow more massive. Once it is charged by even a single electron then it can use the Coulomb force to capture a proton. Etc.

    I agree that the sun will burn out before there is any dangerous accumulation of mass IF the only process available to do so were gravitational capture of nuclei.

    Three false nonsense statements in one post is a "strike out" in my book.
     
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  15. Reiku Banned Banned

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    The math alphameric is piss-easy. It's stuff i learned yonks ago.

    No, i have no reason to talk about your work, but rather, why you seem to be such an angry little man.
     
  16. AlphaNumeric Fully ionized Registered Senior Member

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    It is clear that they are not saying it is electromagnetic in nature, particularly given they say it immediately underneath a title which says the black holes are neutral. Instead they are classifying the kind of interaction. Do the particles in the interaction interact over their entire motion or just from a single 'blow'? If the former, it's a Coulomb like interaction. If it's the latter than it's Compton-like.

    You are basically ignoring the context and despite having been shown that their use of the term is entirely consistent, you continue to clutch desperately to the strawman you'vfe created.
    Which isn't what they are talking about. It's clear from the context and the extra meaning for their terminology you are pretending doesn't exist.

    This is just like Reiku and his "You're not using the right definition!!" when it came to the word 'virtual'. When a physicist says "The interaction is Coulomb like, not Compton like" it would instantly conjure up the image of interactions like this, which is precisely the kind of interaction shown on page 17.

    They didn't say it's the Coulomb force/interaction, they said it's like it. Besides, even if you don't like the terminology they use, their analysis used the right equations and derivations involving gravitational interactions. It's like complaining the paper is written in English and you're German. The predicted outcomes are still the same. If you disagree, show where their quantitative stuff is wrong.
    That was my point. That is Compton scattering. Also, notice how you call it Compton scattering, despite it involving either an electron or a nucleus? In both cases it's because it's a photon coming in and hitting something charged, but the effect is a singular 'blow', not a gradual interaction as they get closer.

    So in one case you yourself use 'Compton scattering' to describe a general process but you are complaining when they do the same thing for Coulomb scattering?
    Passing through the electron shell doesn't mean it will absorb the electron there. The black hole is, in effect, measuring the position of the electron within the shell and the only way it would eat the electron is if the electron, when localised by the measurement, is within the event horizon. So passing through the electron shell doesn't mean it's eaten the electron. The nucleus is an extended object which is packed with all kinds of QCD crap, which the electron shells don't have (do I need to explain why?).

    Think about the black hole being a sphere, radius r, passing through an electron shell, radius R and then through the middle (nucleus has radius R/1000) and out the other side of the electron shall.

    The electron is a point somewhere in the electron shall of surface area \(4\pi R^{2}\). The black hole goes through the electron shell if the distance from the centre of the nucleus to the black hole is less than R+r. I'll over estimate (because it makes for easier maths) the area of the electron shell it sweepts through by saying it cuts a circle through that shell of approximate area \(\pi r^{2}\). So the probability of the electron being captured is \(\frac{r^{2}}{4R^{2}}\), doubled because it goes out the other side, so \(\frac{r^{2}}{4R^{2}}\). The black hole will hit the nucleus if it's event horizon touches or intersects the nucleus in any way. In other words the black holes' centre is anywhere within a distance r+(R/1000) from the centre of the nucleus. That's an area for it to 'hit' of \(\pi (r+(R/1000))^{2}\). And the cross sectional area of the entire 'atom' is \(\pi R^{2}\), so the probability it hits the nucleus when it's within the electron shell is \(\frac{ (r+R/1000)^{2}}{R^{2}}\)

    So the back of an envelope calculation is that the probability of the electron in the orbit being within the event horizon when the black hole passes through is of order \(\frac{r^{2}}{R^{2}}\). The probability the black hole intersects the nucleus is \(\frac{(r+\frac{R}{1000})^{2}}{R^{2}}\).

    You can see that as \(\frac{r}{R} \to 0\) the probability of an electron being eaten goes to 0, while the probability the black hole goes through the nucleus tends to about a millionth. It doesn't go to zero. So if the black hole is much much smaller in it's radius than the size of an atom (and typically they are many trillions of times smaller!) then passing through electron shells and eating an electron isn't a worry but it's chance of passing through the nucleus doesn't go away!

    See, more back of an envelope reasoning which backs up what I'm saying. Simple.
    In each case I've demonstrated that you are either flat out incorrect or assuming that because you don't know the use of a term then it's wrong.

    So the three strikes are yours. I've proven again I know how to do even these simple order of magnitude calculations. Can you do the same, as I've repeatedly asked?

    Or perhaps you'd prefer we go through the lecture notes I've linked to so we can do the REAL details of this stuff.
    But you don't remember how to do the stuff you learnt 'yonks about'. You're rusty at it.
    Perhaps I find your repeated lies tiresome? Perhaps we can talk about why you lie all the time about things you know people not believe you on?

    And I knew you'd not want to talk about my work. Cranks never do because there isn't a Wikipedia page for them to pretend they understand certain terminology and equations I'd post.
     
  17. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    Messages:
    23,198
    I do not disagree with their calculation of the GRAVITATIONAL interaction. - My point is that the gravitational interaction is NOT the important one.

    If stable (perhaps due to quantum effects), the very tiny black hole with less than escape velocity will repeatedly oscillate thru the solid Earth. I and the safety report also agree on that (They say, based on consideration of ONLY the gravitational interaction for more than 4 billion years it will do so.)

    What makes their gravitational analysis pointless is that as it passes thru the solid Earth, it is passing thru "zillions" of electron orbitals each meter or so of it trajectory within the Earth. There is a non-zero, but admittley very small, chance* that one of the electrons in one of the zillions of orbitals will "localize" (behave as a particle, not a wave) inside the event horizon of the black hole, making it no longer electrically neutral. Then it can and will interact much more strongly with the protons of the nuclei it passes near. I.e. scatter and lose energy, eventually come to rest and the force (lets not argue about the name of this force) between that negatively charged black hole and the nearest proton will merge the proton (probably the whole nucleus that the proton is part of) inside the black hole. It will do this at least: 100,000,000,000,000,000,000,000,000,000,000,000 times faster than the weak gravitational force they do ONLY consider can.

    To make an analogy, as you seem very dense:

    Suppose you were standing between the rails of a railroad track with feet set in mass of concrete and a 100 car long train was coming straight at you at 150mph. On the front of this train there is a flea.

    Now some one then says to you: "Do not worry. I have done the calculations correctly in my safety report. - Collision with a flea, even at 150mph, is harmless."

    That is my objection. - I want the much stronger electrical interaction considered, not the extremely weak gravitational interaction from a mass that is much smaller than the mass of a proton! I agree that gravitational interaction is nothing to worry about. That is the "flea." I am concerned about the "train," which the safety report ignores. No where can I find any discussion of the rate at which the tiny black hole will charge or once charged any discussion that acknowledges that the charged tiny black hole will come rest and "eat" at least one proton (or 26 if it is an iron nucleus that it comes to rest near.) Once at rest wrt to the atoms of Earth, it will alternate between "eating" electrons and "eating" positve nuclei -I.e. grow rapidly in mass as the Earth plastically flows toward it under the very high pressure near the center of the Earth. The tiny black hole's gravity has nothing significant to do with the true problem.

    -------
    *The footnote of my prior post, 1566, I told (outlined in rough form) the many steps needed to estimate this probability of electron capture by a neutral, tiny black hole traveling within the Earth.
     
    Last edited by a moderator: Aug 22, 2008
  18. Vkothii Banned Banned

    Messages:
    3,674
    All I know about scattering - apart from all the names like "Coulomb", "Bragg", "Brillouin" etc - is that it is always elastic/inelastic. That is, there is always some inelastic interaction, in an elastic collision, and always some elastic interaction in an inelastic collision, even in a deeply inelastic one. Even if either effect can be ignored, they are still part of the dynamics.

    Compton scattering depends on momentum, and on both elastic and inelastic interactions; it explains the particle-like behaviour of photons (they appear "ballistic" at high energies) and how a photon's frequency gets changed by a partly-inelastic interaction - the photon's frequency shifts because some momentum is transferred to an electron. Same process as the photoelectric effect.
    Coulomb scattering depends on charge as well as momentum, I believe.

    That's my 2c for now. Maybe someone can have fun pulling it apart and telling me how little I understand these things.
     
  19. joepistole Deacon Blues Valued Senior Member

    Messages:
    22,910
    I just want to know, am I dead yet? If not, how much time left before I hear the giant sucking sound?
     
  20. Oli Heute der Enteteich... Registered Senior Member

    Messages:
    11,888
    Bloody government: never tell you anything you really need to know.
    If we are dead does that mean we'll get a tax reduction?
     
  21. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    Messages:
    23,198
    Like many things, the truth of this can depend upon how the two terms are defined, but most physicist, I think, would accept something like:

    A collison is elastict IFF all of the system energy prior to the collison is still of the same high quality (none is thermal for a macroscopic system and none has disappeared from the system, whereas it is perfectly inelastic if all of the initial energy is degraded (to heat) or escapes the system.

    Implicit in this is the idea of a well defined system. Certainly a finte volume.

    Thus, for example, when an electron moving with energy E hits an hydrogen atom at rest (in its ground state) then IFF after the collison the atom is still in the ground state and the electron, with energy Ee, and the recoiling atom has energy Eh such that E = Ee + Eh then that collison is "perfectly elastic."

    I think the first exceited state of hydrogen is 13.6x3/4 eV but what ever it is I now call it E1.

    If E was greater than E1, then after collision, with the h atom in the ground state, the following may be true:

    E = Ee + Eh + E1, but the system has only a total energy of Ee + Eh.

    I.e. E1 has been lost FROM THE SYSTEM as a photon. (This photon actually has a name: "L1" or the first and weakest of the "Lyman series." all the Lyman lines are in the UV. It is the Balmer series that you can see -their lower state is E1 above the ground state.) Most physicsts would call this collision inelastic as E > Ee + Eh. The system has lost usefull energy especially if that L1 photon is on its way to some distant point in space. But some would only call a collison inelastic if heat is produced. I tend to that POV.

    Thus with that POV, I assert that all atomic (or sub atomic) collisions are 100% eleastic as the very concept of heat requires an average over many atoms (or molecules). The concept of "temperature" is even more restrictive. Not all large collections of atoms have a "temperature" as strictly that requires that all the different way they can hold energy have traded it back and forth until no NET amount is now being exchanged. I.e. they are in "thermal equlibrium."

    Now it often happens that the various modes of energy storage can come to a thermal distribution (called the Boltzmann distrbution) with different temperatures in the math describing the Boltzman distribution. Then, for example, one can speak of the the "ion temperature" and the "electron temperature" in a plasma etc. for other systems with well separated modes of storing energy.

    The classic example of a perfectly inelastic collison is a wad of clay stuck to the side of a massive building with a bb fired into the clay. After that collision there is only heat.

    Hope that helps (an was not too boring - hard to stop an old professor who still likes to teach). Except for this bit about there always being a mix of elastic and ineleastic, your post was OK, and even this "error" could be made to go away by some definitions and nit picking. (Didn´t the building sway just a little after the bb hit the clay? etc.)

    As this is off thread, please read posts 1574 and then to understand it better 1524, and if still interested, then the arguement between these two. It seems that AlphaNumerica has finnally gotten my point as he is not replying to 1574, but perhaps he is busy with other things now.
     
    Last edited by a moderator: Aug 24, 2008
  22. AlphaNumeric Fully ionized Registered Senior Member

    Messages:
    6,702
    I came home on Friday from university and I've spent the time doing considerably less than I usually do, including posting online.

    Frankly there seems little worth replying to. You don't back up anything you say, you don't make an attempt to understand mainstream concepts, you continue whining about your lack of understanding of terminology, you cannot even do 'back of an envelope' calculations, despite my demonstration of how straight forward they are.

    The only 'point' of yours I've gotten is that you are like Walter and Paul, you like to try to talk the talk but when it comes down to it, you can't actually do or back up anything you talk about.

    http://motls.blogspot.com/2008/02/lhc-alarmists.html
     
    Last edited: Aug 24, 2008
  23. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    Messages:
    23,198
    Your outline concerned the GRAVITATIONAL interaction between the Tiny Black Hole, TBH, and matter inside the Earth (nuclei mainly). Doing that is pointless for two reasons:

    (1) It is well done in the safety report.
    (2) The gravitational interaction force is at least 100,000,000,000,000,000,000,000,000,000,000,000,000

    times WEAKER than the important ELECTRICAL interaction between a charged TBH, even if the charge it has is only that of a single electron.

    In post 1566´s footnote I outlined how to calculate the probability that the TBH will become charged. (“Eat” one of the “zillions” of electrons whose bound orbitals it passes thru in each meter of its travel thru the Earth.) The TBH will pass thru the entire Earth about 12,000 times each year, until it does be come charged, and then rapidly comes to rest near the center of the Earth, but I suspect it will become charged before the first complete pass is completed – i.e. in less than the 45 minutes it will be resting near the center of the Earth and pulling the nearest positive nucleus in side its Event Horizon, by ELECTRICAL force attraction. I.e. after it is charged, gravity plays no role in causing the TBH to rapidly gain mass.

    As you are fixated on the un-important force I made following analogy for you:

    Suppose you were standing between the rails of a railroad track with feet set in mass of concrete and a 100 car long train was coming straight at you at 150mph. On the front of this train there is a flea.

    Now some one then says to you: "Do not worry. I have done the calculations correctly in my safety report. - Collision with a flea, even at 150mph, is harmless."


    That is my objection. - I want the much stronger electrical interaction considered, not the extremely weak gravitational interaction from a mass that is much smaller than the mass of a proton!

    Apparently your skull is too thick to understand, even with the help of this analogy, that one must be concerned with the strong important Electrical Force (the train) and not the un-important Gravitational Force (the flea).

    I am not trying to prove anything by this analogy – only to expose your fixation on the weak gravity force, which is not important. I will stop trying to make you under stand this as it seems to be impossible. Your can continue to be happy that the flea (gravity interaction) will not hurt you. You can even continue to say I am only "winning" when I point out that it is the electrical, not the gravitational, interaction that is important as I will not bother anymore trying to make you understand this.
     
    Last edited by a moderator: Aug 24, 2008

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