Taking a Fresh Look at the Physics of Radiometers.
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From: BURT on 5 Jun 2010 20:24 On Jun 5, 5:06 pm, NoEinstein <noeinst...(a)bellsouth.net> wrote: > On Jun 5, 6:29 pm, "Tim BandTech.com" <tttppp...(a)yahoo.com> wrote: > > Dear Tim: My reading speed can't take in all that you are saying. > But I don't disagree. The 'missing link' of your Black Body rationale > is that the white light coming in has more energy per 'ray'. To have > the same infrared radiation, there have to be a higher number of > rays. It's likely that it's the number of rays that account for the > amount of ether ejected along with the photons. In the Crookes, light > reflecting from the white squares, and the ether ejected in the same > direction, push some of the argon atoms toward the adjacent (opposed) > black squares. It is the mass of those argon atoms which causes the > vanes to rotate, not heat "rocketing" from the porous edges of the > vanes! NoEinstein > > > > > > > On Jun 4, 5:40 pm, Timo Nieminen <t...(a)physics.uq.edu.au> wrote: > > > > On Jun 4, 9:59 pm, "Tim BandTech.com" <tttppp...(a)yahoo.com> wrote: > > > > On Jun 3, 5:59 pm, Timo Nieminen <t...(a)physics.uq.edu.au> wrote: > > > > > On Jun 4, 7:09 am, "Tim BandTech.com" <tttppp...(a)yahoo.com> wrote: > > > > > > Here is another link in support of the challenge to radiation > > > > > > pressure's validity: > > > > > > "It is therefore much more likely that in a given case the apparent > > > > > > 'radiation pressure' is caused either by thermal surface effects or > > > > > > electrons which are released from the surface by the radiation." > > > > > > -http://www.physicsmyths.org.uk/#radpress > > > > > > That is a _really_ bad webpage! Just consider its claim: "Even if one > > > > > assumes a momentum, a radiation pressure force could only be caused by > > > > > a momentum change dp/dt, but this is not possible because the speed of > > > > > light c has to be constant" (1) Direction of motion matters when it > > > > > comes to momentum, (2) refractive index. > > > > > Yes, and this is very similar to the arguments that I have provided.. > > > > ! I haven't seen you directly arguing such complete nonsense. That web > > > page was saying that the direction of motion doesn't affect momentum, > > > that if an object changes direction and goes, e.g., in the exact > > > opposite direction, there is no change in momentum. Before you claim > > > that the argument given there is very similar to yours, you should > > > understand just how completely defective that argument is. > > > > > The conservation of momentum is a strict principle, one that you have > > > > already cast aside in your argument about changing momenta as media > > > > change in dielectric quality > > > > ?? Conservation of momentum is why, if the momentum flux of the beam > > > changes, there must be a matching force on the surface, or, if there > > > is a force on the surface of the liquid (as we observe > > > experimentally), then the momentum flux of the beam must change? > > > > Why do you say this "casts aside" conservation of momentum? It's > > > directly based on the conservation of momentum. > > > > > You already accepted once the farce of > > > > the reflector as a doubling agent of radition pressure effects, and > > > > then go back to supporting it. What do you have to say about > > > > conservation of momentum? > > > To support my claim above I quote from your own words > > > "If the reflector is moving, there will be a Doppler shift, > > and energy in will be different from energy out. > > If the reflector is stationary, then you could have, e.g., > > 1300W in and 1300W out. But no work would be done." > > > -http://groups.google.com/group/sci.physics/msg/f064666482b7c3b5 > > > I don't mean to be crass but I do mean to use this medium with > > accountability, which is one of its strong points. I would like you to > > find such falsifications in my own writing. > > > The radiation pressure effect is claimed to be operant even with no > > initial relative velocity between the source and reflector. Further, > > as far as I can tell none of the existing work on radiation pressure > > relies upon any red shift argument as the balance of energy. Simply > > put, if the perfect reflector reflects all of the beams light back > > toward the source then it cannot have absorbed any energy and hence it > > will not accelerate. > > > Next, if we do take the accepted photon momentum derived from > > e = h f > > then we would witness the entire 1300 watts of power on a square meter > > of mirror, which should do quite some work according to this accepted > > momentum equation, particularly for those fond of a doubling effect. > > Clearly this is not the source of radiation pressure. Even if we go to > > a black body which absorbs the energy, we must admit that there is no > > effect; The energy is converted into heat, to be reradiated, and if we > > assume that this reradiation is isotropic then we need not bother with > > any directed effect from it within the already corrupted concept of > > photon momentum. All the while you stand by the photon momentum > > equation, even while it fails to provide any momentum. This argument > > on momentum does not necessarily have anything to do with the claimed > > existence of radiation pressure. > > > The heating effect is nearby to the redshift concept, but again, we > > are not necessarily talking about radiation pressure here. This is an > > altogether different effect as far as I can tell. Wouldn't we have to > > get into thermodyamics more and Planck's energy distribution to > > discuss this effect? You see, it is a bit crazy how many sidelines > > there are, and so long as we wish to discuss the radiometer as a means > > of measuring radiation pressure, well, we are not really discussing a > > radiometer any more. These fine points you seem not to have > > acknowledged though I've stated them several times. You have pretty > > much accepted (I believe) that there will be no effect in the best > > vacuum labs available. Isn't this enough to admit that you do not > > believe that radiation pressure exists? > > > As I see it the problem of human as scientist is embedded within this > > discussion. Upon an 'accepted' theory being posited, for one to break > > away from that norm places one as a potential quack. And yet, without > > this freedom of thought, the quality of science will suffer. Such a > > person has relinquished their freedom to falsify, and in doing so has > > guaranteed their success within a system where mimicry is a merit. I > > respect your rights, particularly here on this free medium, but I > > would point out to you that as a partially accurate sounding board to > > existing theory you are in some regards helping to disprove that > > theory. > > > As you argue for the radiation pressure on a perfect reflector in > > outer space why would you deny that it can be provided in a lab at > > 10E-11 torrs with a 10kW laser? Should this be enough to turn the > > spindle of a Crooks style radiometer, or is the friction too great? > > Really, I must admit that I am growing cynical here, if for no other > > reason than the fact that your response to this question will be > > miserable to read. > > > You are a strong poster Timo and I don't mean you any harm. I can't > > have this discussion without you. I find it poor that people who claim > > to be scientific will not apply themselves at this level. I ask that I > > be falsified, and you are the only one who steps forward. I am still > > open to such falsification, and it could turn on some minor point or > > discrepancy that we are overlooking. Still, could it be the other way > > around too? One must give ones self enough credit to declare something > > false if one is to give one's self enough credit to declare something > > to be true. Otherwise mimicry ensues, and this is a transparent human > > factor inculcated within the schooling. I give you as much credit as I > > can but attempt to hold you accountable. Thanks, Timo, for hanging in > > there. I half take back my prediction on your response. > > > - Tim > > > > You don't think the momentum of an object that reverses direction > > > changes? You don't think that a force (i.e., a change in momentum as > > > per Newton) is needed to change the direction of an object? > > > > If one instead, at least provisionally, accepts Newton's laws of > > > motion as correct, if an object with momentum p reverses direction, > > > while maintaining the same speed, the final momentum is -p, for a > > > change in momentum of -2p, with an average force of -2p/t where t is > > > the time over which the force that causes the change in direction is > > > applied. If instead, the object is "absorbed", has a sticky collision, > > > then the change in momentum is -p, only half of the "reflection" > > > change in momentum. What's so mysterious about radiation pressure on a > > > reflector being double?- Hide quoted text - > > > - Show quoted text -- Hide quoted text - > > > - Show quoted text -- Hide quoted text - > > - Show quoted text - Hey NoEinsein Light bulbs are flooding quadrillions of light waves into a room every second. But what happens to them when the light is turned off? They don't leave the room. But if they go into matter are they absorbed or unabsorbed as heat? An atom at a matterial surface after absorbing light has the probability for emmiting light either outward of itself or inward inside the atom toward the nucleus or sideways to the atom Emmision goes spherical 360 degrees and is stochastic appearently. If there is order to emmision I have yet to see it. This means that atoms can keep emmiting light deeper into the surface. And all of this is probability. Mitch Raemsch
From: NoEinstein on 6 Jun 2010 02:33 On Jun 5, 8:24 pm, BURT <macromi...(a)yahoo.com> wrote: > Dear Burt: Photons don't get "lost" inside of reflecting surfaces. The photon energy will be expelled 1/2 wavelength later, even if there are hundreds of internal, atom-to-atom exchanges. Light of any kind is radiant energy which can warm a room. Black (or dark) surfaces are slower to release the radiant energy, and might even release some of the heat by conduction or convection. In the present discussion on Radiometers, the convection is small due to the vacuum in the bulb. And the conduction is small due to the isolated design of the four vanes. NoEinstein > > On Jun 5, 5:06 pm, NoEinstein <noeinst...(a)bellsouth.net> wrote: > > > On Jun 5, 6:29 pm, "Tim BandTech.com" <tttppp...(a)yahoo.com> wrote: > > > Dear Tim: My reading speed can't take in all that you are saying. > > But I don't disagree. The 'missing link' of your Black Body rationale > > is that the white light coming in has more energy per 'ray'. To have > > the same infrared radiation, there have to be a higher number of > > rays. It's likely that it's the number of rays that account for the > > amount of ether ejected along with the photons. In the Crookes, light > > reflecting from the white squares, and the ether ejected in the same > > direction, push some of the argon atoms toward the adjacent (opposed) > > black squares. It is the mass of those argon atoms which causes the > > vanes to rotate, not heat "rocketing" from the porous edges of the > > vanes! NoEinstein > > > > On Jun 4, 5:40 pm, Timo Nieminen <t...(a)physics.uq.edu.au> wrote: > > > > > On Jun 4, 9:59 pm, "Tim BandTech.com" <tttppp...(a)yahoo.com> wrote: > > > > > On Jun 3, 5:59 pm, Timo Nieminen <t...(a)physics.uq.edu.au> wrote: > > > > > > On Jun 4, 7:09 am, "Tim BandTech.com" <tttppp...(a)yahoo.com> wrote: > > > > > > > Here is another link in support of the challenge to radiation > > > > > > > pressure's validity: > > > > > > > "It is therefore much more likely that in a given case the apparent > > > > > > > 'radiation pressure' is caused either by thermal surface effects or > > > > > > > electrons which are released from the surface by the radiation." > > > > > > > -http://www.physicsmyths.org.uk/#radpress > > > > > > > That is a _really_ bad webpage! Just consider its claim: "Even if one > > > > > > assumes a momentum, a radiation pressure force could only be caused by > > > > > > a momentum change dp/dt, but this is not possible because the speed of > > > > > > light c has to be constant" (1) Direction of motion matters when it > > > > > > comes to momentum, (2) refractive index. > > > > > > Yes, and this is very similar to the arguments that I have provided. > > > > > ! I haven't seen you directly arguing such complete nonsense. That web > > > > page was saying that the direction of motion doesn't affect momentum, > > > > that if an object changes direction and goes, e.g., in the exact > > > > opposite direction, there is no change in momentum. Before you claim > > > > that the argument given there is very similar to yours, you should > > > > understand just how completely defective that argument is. > > > > > > The conservation of momentum is a strict principle, one that you have > > > > > already cast aside in your argument about changing momenta as media > > > > > change in dielectric quality > > > > > ?? Conservation of momentum is why, if the momentum flux of the beam > > > > changes, there must be a matching force on the surface, or, if there > > > > is a force on the surface of the liquid (as we observe > > > > experimentally), then the momentum flux of the beam must change? > > > > > Why do you say this "casts aside" conservation of momentum? It's > > > > directly based on the conservation of momentum. > > > > > > You already accepted once the farce of > > > > > the reflector as a doubling agent of radition pressure effects, and > > > > > then go back to supporting it. What do you have to say about > > > > > conservation of momentum? > > > > To support my claim above I quote from your own words > > > > "If the reflector is moving, there will be a Doppler shift, > > > and energy in will be different from energy out. > > > If the reflector is stationary, then you could have, e.g., > > > 1300W in and 1300W out. But no work would be done." > > > > -http://groups.google.com/group/sci.physics/msg/f064666482b7c3b5 > > > > I don't mean to be crass but I do mean to use this medium with > > > accountability, which is one of its strong points. I would like you to > > > find such falsifications in my own writing. > > > > The radiation pressure effect is claimed to be operant even with no > > > initial relative velocity between the source and reflector. Further, > > > as far as I can tell none of the existing work on radiation pressure > > > relies upon any red shift argument as the balance of energy. Simply > > > put, if the perfect reflector reflects all of the beams light back > > > toward the source then it cannot have absorbed any energy and hence it > > > will not accelerate. > > > > Next, if we do take the accepted photon momentum derived from > > > e = h f > > > then we would witness the entire 1300 watts of power on a square meter > > > of mirror, which should do quite some work according to this accepted > > > momentum equation, particularly for those fond of a doubling effect. > > > Clearly this is not the source of radiation pressure. Even if we go to > > > a black body which absorbs the energy, we must admit that there is no > > > effect; The energy is converted into heat, to be reradiated, and if we > > > assume that this reradiation is isotropic then we need not bother with > > > any directed effect from it within the already corrupted concept of > > > photon momentum. All the while you stand by the photon momentum > > > equation, even while it fails to provide any momentum. This argument > > > on momentum does not necessarily have anything to do with the claimed > > > existence of radiation pressure. > > > > The heating effect is nearby to the redshift concept, but again, we > > > are not necessarily talking about radiation pressure here. This is an > > > altogether different effect as far as I can tell. Wouldn't we have to > > > get into thermodyamics more and Planck's energy distribution to > > > discuss this effect? You see, it is a bit crazy how many sidelines > > > there are, and so long as we wish to discuss the radiometer as a means > > > of measuring radiation pressure, well, we are not really discussing a > > > radiometer any more. These fine points you seem not to have > > > acknowledged though I've stated them several times. You have pretty > > > much accepted (I believe) that there will be no effect in the best > > > vacuum labs available. Isn't this enough to admit that you do not > > > believe that radiation pressure exists? > > > > As I see it the problem of human as scientist is embedded within this > > > discussion. Upon an 'accepted' theory being posited, for one to break > > > away from that norm places one as a potential quack. And yet, without > > > this freedom of thought, the quality of science will suffer. Such a > > > person has relinquished their freedom to falsify, and in doing so has > > > guaranteed their success within a system where mimicry is a merit. I > > > respect your rights, particularly here on this free medium, but I > > > would point out to you that as a partially accurate sounding board to > > > existing theory you are in some regards helping to disprove that > > > theory. > > > > As you argue for the radiation pressure on a perfect reflector in > > > outer space why would you deny that it can be provided in a lab at > > > 10E-11 torrs with a 10kW laser? Should this be enough to turn the > > > spindle of a Crooks style radiometer, or is the friction too great? > > > Really, I must admit that I am growing cynical here, if for no other > > > reason than the fact that your response to this question will be > > > miserable to read. > > > > You are a strong poster Timo and I don't mean you any harm. I can't > > > have this discussion without you. I find it poor that people who claim > > > to be scientific will not apply themselves at this level. I ask that I > > > be falsified, and you are the only one who steps forward. I am still > > > open to such falsification, and it could turn on some minor point or > > > discrepancy that we are overlooking. Still, could it be the other way > > > around too? One must give ones self enough credit to declare something > > > false if one is to give one's self enough credit to declare something > > > to be true. Otherwise mimicry ensues, and this is a transparent human > > > factor inculcated within the schooling. I give you as much credit as I > > > can but attempt to hold you accountable. Thanks, Timo, for hanging in > > > there. I half take back my prediction on your response. > > > > - Tim > > > > > You don't think the momentum of an object that reverses direction > > > > changes? You don't think that a force (i.e., a change in momentum as > > > > per Newton) is needed to change the direction of an object? > > > > > If one instead, at least provisionally, accepts Newton's laws of > > > > motion as correct, if an object with momentum p reverses direction, > > > > while maintaining the same speed, the final momentum is -p, for a > > > > change in momentum of -2p, with an average force of -2p/t where t is > > > > the time over which the force that causes the change in direction is > > > > applied. If instead, the object is "absorbed", has a sticky collision, > > > > then the change in momentum is -p, only half of the "reflection" > > > > change in momentum. What's so mysterious about radiation pressure on a > > > > reflector being double?- Hide quoted text - > > > > - Show quoted text -- Hide quoted text - > > > > - Show quoted text -- Hide quoted text - > > > - Show quoted text - > > Hey NoEinsein > > Light bulbs are flooding quadrillions of light waves into a room every > second. But what happens to them when the light is turned off? They > don't leave the room. But if they go into matter are they absorbed or > unabsorbed as heat? > > An atom at a matterial surface after absorbing light has the > probability for emmiting light either outward of itself or inward > inside the atom toward the nucleus or sideways to the atom Emmision > goes spherical 360 degrees and is stochastic appearently. If there is > order to emmision I have yet to see it. > > This means that atoms can keep emmiting light deeper into the surface. > And all of this is probability. > > Mitch Raemsch- Hide quoted text - > > - Show quoted text -
From: Tim BandTech.com on 6 Jun 2010 09:05 > On Jun 6, 8:29 am, "Tim BandTech.com" <tttppp...(a)yahoo.com> wrote: Hey, great snip here Timo! Thanks for clipping out your own contradiction. The usenet dodge is in effect. I will attempt to do better as you will see below. The one thing for sure about this medium is that mistakes can be made, and this is entirely acceptable. This allows us to exercise mistake detection, which is a skill that needs more development. It's going to be the only way out of the pile-up that is modern physics. Beyond this, credibility exists more for those who admit their mistakes than it does for the usenet dodger. Well, I should admit we each are actually doing pretty well at holding our feet to the fire. > > To support my claim above I quote from your own words > > > "If the reflector is moving, there will be a Doppler shift, > > and energy in will be different from energy out. > > If the reflector is stationary, then you could have, e.g., > > 1300W in and 1300W out. But no work would be done." > > > -http://groups.google.com/group/sci.physics/msg/f064666482b7c3b5 > > > I don't mean to be crass but I do mean to use this medium with > > accountability, which is one of its strong points. I would like you to > > find such falsifications in my own writing. > > > The radiation pressure effect is claimed to be operant even with no > > initial relative velocity between the source and reflector. Further, > > as far as I can tell none of the existing work on radiation pressure > > relies upon any red shift argument as the balance of energy. Simply > > put, if the perfect reflector reflects all of the beams light back > > toward the source then it cannot have absorbed any energy and hence it > > will not accelerate. > > Yes, it will work with no relative velocity between source and > reflector. Don't handwave! Say specifically where my redshift/ > blueshift derivation is wrong. If it isn't wrong, it's right. This accusation of handwaving is false. I find this an interesting form of denial. I was recently criticized for constructing a straw man argument, which was itself a straw man argument. Such iterative discrepancies are fascinating and perhaps are operant within the human mind, and would help to explain our poor observational abilities. What does it mean to observe? Well, the gedanken observer merely marks down some strict number, but for the human the observant have already entered the theoretical realm. Perhaps we are suffering from this ambiguation and should resolve it. Here is a fine point on detachment from philosophy within the modern physics position, and a minor falsification of Einstein's construction technique. These subtleties coupled to human nature are like a substrate that we inhabit, with no direct access to the substrate. > > > Next, if we do take the accepted photon momentum derived from > > e = h f > > then we would witness the entire 1300 watts of power on a square meter > > of mirror, which should do quite some work according to this accepted > > momentum equation, particularly for those fond of a doubling effect. > > Why? 1300W gives you 4 micronewtons (9 micronewtons if reflected). > This gives you "quite some work"? That's a tiny force, expecially > considering it's acting on something 1m^2 in area. > > > You have pretty > > much accepted (I believe) that there will be no effect in the best > > vacuum labs available. Isn't this enough to admit that you do not > > believe that radiation pressure exists? > > Absolutely not. Go back and read what I wrote! > > > As you argue for the radiation pressure on a perfect reflector in > > outer space why would you deny that it can be provided in a lab at > > 10E-11 torrs with a 10kW laser? Should this be enough to turn the > > spindle of a Crooks style radiometer, or is the friction too great? > > Really, I must admit that I am growing cynical here, if for no other > > reason than the fact that your response to this question will be > > miserable to read. > > I don't deny it at all that it would work in a lab at ultra-high > vacuum. I said that it does work in the lab at UHV, as seen by the > various atom trapping/cooling and BEC experiments. > > Would it be enough to turn a Crookes radiometer? Depends on the power. > Levitate the rotor magnetically, avoid friction. Nichols and Hull > avoided friction. > > > You are a strong poster Timo and I don't mean you any harm. I can't > > have this discussion without you. I find it poor that people who claim > > to be scientific will not apply themselves at this level. I ask that I > > be falsified, and you are the only one who steps forward. I am still > > open to such falsification, > > Are you? I say that UHV experiments have been done, on atoms. I say > that radiation pressure forces have been observed on macroscopic > objects, between collisions with atoms in the low-pressure gas, so > equivalent to UHV in principle. I say that radiation pressure forces > would be observable in an UHV experiment. Your response: "why would > you deny that it can be provided in a lab at 10E-11 torrs with a 10kW > laser?" Apart from the fact that I didn't mention a 10kW laser, nor > did you until now, what you are claiming I said is the opposite of > what I said. So, is there any point discussing the various experiments > if you don't read what I write? Well, I have gone back to check what I remember pretty well that you wrote, and you state that it will not be observed in perfect vacuum: "Perfect vacuum, no. Very good vacuums, yes, especially with atom trapping. I've seen classical experiments done in vacuum (can't recall how good), where absorbing particles were blasted by short pulses of light, to measure their radiation pressure cross-sections." in response to my statement: "I'm sorry but the effect in a perfect vacuum has not been clearly demonstrated. As you've accepted the flaws of Nichols work then the question of whether the radiation pressure is observable in vacuum still exists. The experiments that you've exposed in your paper must not be the modern experiments that you speak of." I stand corrected and apologize for the misinformation. I suppose that what you meant was that we cannot generate a perfect vacuum. Now, the only thing we need to do is turn up an experiment on solids rather than fluids or particles that takes into consideration the strength of the vacuum, no different than Nichols himself did, but beyond the .02 torr mark; preferably heading all the way to the limit of the modern equipment, and observe the characteristic curve of diminishment of the gas effect, as Nichols did. I have been avoiding your references to optical tweezers and light traps, partially because I have only limited familiarity with those. Anyway, we are in agreement that radiation pressure should be measurable at 10E-11 torrs using a solid plate device. > > Don't avoid the redshift/blueshift derivation then. It's simple, and > follows only from the energy of light and conservation of energy. You > don't need to assume that light carries momentum; this follows as a > consequence. No. I will continue to attempt these as seperate tendrils of this thread. The redshift concept stands alone away from the photon momentum, and this too stands alone away from the radiation pressure. These three concepts may be related, but it is their isolation that we are after. Again, there is no need of any velocity other than the velocity of the light under the initial conditions of a target in stasis with a source, as at a laboratory light table, with a laser pinned to the table shining into an evacuated compartment pinned to the table with either a Crooks device or a Nichols device inside initially at zero velocity and under the Nichols case settling to zero velocity via a torsion fiber. The only parameter here are the power of the light, which supposedly is related to radiation pressure, the strength of the vacuum, and perhaps the amount of friction in the measuring device. Well, clearly there are more parameters, but the isolation of radiation pressure seems possible under this situation, with the exception of the reradiated energy of the detector, and possibly freed electrons as one of the links in support of my position mentions. When we start thinking of those electrons then the tweezers and traps start to make more sense I think, but I cannot argue on these devices without doing some research. If this experiment has been done why can't we find it? If it has not been done then why not? If Nichols work were falsifiable then we should see a next gen, no different than Nichols followed Crooks. Ahah! I just found one! http://iopscience.iop.org/0959-5309/45/2/315 Reads pretty much like some of this discussion, but in 1933. He calls Nichols and Hull's work a 'paper dagger'. He gets down to 10E-6 torr. I can't access the whole paper, but the intro reads easy. If I was a real hanger on I would try to consider the free electron problem. For instance, did he try using some static E fields to vary the experiment? I will try to go through the theory again. The doubling claim still troubles me. I guess if you want to argue the doubling effect some more I can try, but I'd rather go over to the black body stuff and try to understand just how literally the photon momentum is taken. If it's all in e=hf then it is a lie, because the 1300 watts per square meter of sun would be observed as a mechanical force. This is likely a matter of interpretation. As I approach this as an open problem, then it seems blatantly apparent that what we just claimed as an isolational experiment on radiation pressure can actually be taken as a claim to have isolated photon momentum as much more miniscule than the e=hf derivation. This then could be twisted into photon mass, and as it is such a slight figure, then all the better. The radiation pressure is not unlike electron spin, in that it is a small effect that is difficult to notice and for me, difficult to understand. Incidentally, the p=u/3 that I see in other sources is not the equation you rely upon. The gyrations possible within this realm are ridiculously complex. Electromagnetism itself is a kaleidoscope of behaviors and we already are working under the conflicted wave/ particle duality. This is a great topic. Thanks Timo for your time on this thread. - Tim
From: NoEinstein on 6 Jun 2010 16:39 On Jun 5, 3:25 pm, "Tim BandTech.com" <tttppp...(a)yahoo.com> wrote: > Dear Tim: Since I replied to this same reply of yours, earlier, I've realized that the Moon is being held in orbit about the Sun; and being held in orbit about the Earth, by the radiations exchanged among those three. Lunar eclipses don't send the moon flying out on its tangent, probably because the ether pressure "reserve" is greater than the ether pressure lost due to being in the shadow. The shadow must be maintained long enough so the ether pressure reserve gets used up. The following might be considered science 'fiction', now, but one day mankind may be able to maneuver, say, the planet Mars completely out of the solar system. This will require having an artificial satellite, with a huge reserve of FUSION power, to provide the "solar" energy to maintain life on the revolving planet. The destination would be a star young enough to sustain human life for a few billion years. And... it might be possible, by controlling solar flares and sunspots, to turn the Sun into a propulsion system to carry the entire solar system close enough to another 'younger' star, to facilitate the relocation. Forgive my "imagined" science. Real physics would have to apply there, too! NoEinstein > > On Jun 5, 12:55 pm, NoEinstein <noeinst...(a)bellsouth.net> wrote: > > > On Jun 5, 1:19 am, Timo Nieminen <t...(a)physics.uq.edu.au> wrote: > > > Dear Timo: Have I turned you... religious? "How long wilt (I) speak > > these things? And how long will the words of (my) mouth be like a > > strong wind?" Answers: I'll keep speaking the truth until the > > largely dull 'scientific' community wises up. Since my New Science > > fits the observations of the entire Universe, I can speak, with > > authority, that no "detail" of my science will change the whole of my > > discoveries. Note: Throughout the Universe, "the wind" is most often > > ether flow caused by pressure differentials. The maximum pressure is > > always closest to where the mass(es) is most concentrated. Photon > > emission (including infrared) depletes part of the ether INSIDE > > matter. That causes a vacuum that keeps drawing in new ether from > > outside. Matter that receives photons from other matter isn't as > > 'deficient' in ether on the facing sides. So, the net 'replacement' > > energy will flow in on the opposing sides. It is the DRAG of the > > flowing ether on the matter on the opposing sides of the masses that > > PUSHES the masses together. I. e.: the moon and the Earth are > > orbitally bound in this way. Thats how gravity works! NoEinstein > > > > > > On Jun 5, 1:53 pm, NoEinstein <noeinst...(a)bellsouth.net> wrote: > > > > > Dear Timo: You had said, earlier: "This isn't true. The force on the > > > > vanes has been measured in vacuum, and the force is in the opposite > > > > direction to the usual Crookes radiometer thermal force. If not for > > > > friction, the radiometer in vacuum would rotate "backwards"." Since > > > > my New Science has the direction of rotation identical to the Crookes > > > > (black squares trailing), your statement seemed to be saying that my > > > > New Science is wrongwhich it of course, isn't. The wrongly assumed > > > > 'forward' rotation is for the white squares to trail. Friction can > > > > STOP or prevent a rotation, but never change its direction. If you > > > > are wishing to change the subject to "momentum", you are way over your > > > > head. I wrote the book on momentum and KE. PD has fought on those > > > > subjects for three years, and has lost (to me). The world doesn't > > > > need any more PDs! NoEinstein > > > > Job 8:2 > > Hi NoEinstein. I honestly haven't carefully considered your argument, > but I do believe that it will be consistent with gravitational > shadowing, and perhaps a means of describing some of what modern jibe > calls 'dark matter'. > > This is a bit of a scary subject, for it would bring huge interest > from astrologers who concern themselves with the dynamics of such > situations. Will we be forced to admit under this theory that when the > moon passes between the sun and the earth that some of the > gravitational force has disappeared? This is what I mean by > gravitational shadowing. It is an interesting concept, especially when > tied into electromagnetic radiation. I don't feel it is a complete > theory, and feel spread pretty thin trying to consider it within the > radiation pressure claim. Still, they are nearby to each other. > > There are so many possible variations on the Crooks and Nichols > radiometers. There is not necessarily any need to expose more than one > vane of the Crooks device to light in order to experiment, so that the > black/silver conundrum could be deleted. Further I have not found any > analysis on a spinning bearing versus a quartz fiber's friction, but I > presume that a fine enough pin style bearing on a hard jewel concavity > could have a very slight amount of friction relative to the torque of > a fairly distant vane, not to mention more advanced options such as a > magnetic bearing. I've attempted some research on this but found > nothing yet. Any links on this bearing friction analysis are welcome. > I have made some simple bearing out of copper arms resting on a nail > and it is such a nice simple thing that a child can do it. Even wood > on wood bearings are nicely behaved, and can make pretty windvanes, a > few of which I have around my garden. > > - Tim- Hide quoted text - > > - Show quoted text -
From: Timo Nieminen on 6 Jun 2010 16:44
On Jun 6, 11:05 pm, "Tim BandTech.com" <tttppp...(a)yahoo.com> wrote: > > Well, I have gone back to check what I remember pretty well that you > wrote, and you state that it will not be observed in perfect vacuum: > "Perfect vacuum, no. Very good vacuums, yes, especially with atom > trapping. I've seen classical experiments done in vacuum (can't recall > how good), where absorbing particles were blasted by short pulses of > light, to measure their radiation pressure cross-sections." > > in response to my statement: > "I'm sorry but the effect in a perfect vacuum has not been clearly > demonstrated. [...] No, I said the experiment hasn't been *done* in a perfect vacuum. Because we can't achieve a perfect vacuum in the lab. Technically, you were correct. We also haven't done an experimental test of Newton's 1st law, because we don't have a friction free, viscous drag free, force free laboratory. This doesn't mean that I think that Newton's 1st law doesn't work in perfect vacuum. It's an important point. How do we know when we can extrapolate a good vacuum result (or poor vacuum, or atomospheric result) to perfect vacuum? It's important to know (by measuring) the effect of what is there, e.g., damping due to viscous drag, drag due to convective flow, the radiometer force, the effect of the gas on the temperature difference between the two sides of the vane, etc. > I have been avoiding your references to optical tweezers and light > traps, partially because I have only limited familiarity with those. They're the main modern application of radiation pressure. *Thousands* of experiments have been done. Early experiments to show that the method works, and to explore the theoretical principles, experiments to use the force e.g. for restraining or moving live cells, experiments to quantitatively measure forces between biomolecules. > Anyway, we are in agreement that radiation pressure should be > measurable at 10E-11 torrs using a solid plate device. In principle. Whether the force is too small to measure in practice is the question, and this depends on the particular setup. > ... and > possibly freed electrons as one of the links in support of my position > mentions. When we start thinking of those electrons then the tweezers > and traps start to make more sense I think, but I cannot argue on > these devices without doing some research. Freed electrons are not responsible for the force in general. The atom trapping experiments are quite conclusive on this (since freeing an electron would result in ionisation, which would result in the ion not being trapped). (Perhaps in some specific experiment? In the modern laser experiments, there isn't enough photon energy for (significant) photoejection of electrons. Given 1/2 of the photon energy used to eject the electron, the rest becoming its KE, electron ejection would give about 400 times as much force per photon. If this was significant in the various tweezers experiments, it would be observed, as it would thoroughly overcome the trapping force. It would also give an interesting wavelength dependence.) > If this experiment has been done why can't we find it? If it has not > been done then why not? > If Nichols work were falsifiable then we should see a next gen, no > different than Nichols followed Crooks. > > Ahah! I just found one! > http://iopscience.iop.org/0959-5309/45/2/315 > Reads pretty much like some of this discussion, but in 1933. > He calls Nichols and Hull's work a 'paper dagger'. > He gets down to 10E-6 torr. > I can't access the whole paper, but the intro reads easy. So, a later and better repeat of Nichols and Hull. N&H (or the widespread quoting of their result as "definitive") are criticised since the discrepancy between theory and experiment was 10% (due to the effect of the gas). Hull had a paper a few years after N&%, 1905 iirc, on the elimination of gas action, or similar title. This might give some idea of what N&H thought at the time. Bell (and Green) had another paper the next year, with Hull as 1st author. (I briefly read the paper you link above some years ago, but not the others). > The > doubling claim still troubles me. > > I guess if you want to argue the doubling effect some more I can try, The doubling is no more, no less, than you have with similar doubling in the reflection of ping pong balls, billiard balls, etc. The impulse needed to reverse the momentum of an object is double that needed to stop the momentum of an object (straight from Newton 2). Acting in the same time, the reflection force must be double the stopping force. > but I'd rather go over to the black body stuff and try to understand > just how literally the photon momentum is taken. If it's all in e=hf > then it is a lie, because the 1300 watts per square meter of sun would > be observed as a mechanical force. Why would it be observed? 4 (or 9) micronewtons per square meter? Compare this with the gravitational force on a practical plate of the same area. (Perhaps also compare this with forces due to Brownian motion?) > This is likely a matter of > interpretation. As I approach this as an open problem, then it seems > blatantly apparent that what we just claimed as an isolational > experiment on radiation pressure can actually be taken as a claim to > have isolated photon momentum as much more miniscule than the e=hf > derivation. This then could be twisted into photon mass, and as it is > such a slight figure, then all the better. You keep saying that this is problem, but I don't see why. Why is it a problem? E=hf gives a very, very, small force. E = hf, energy of photon, momentum = E/c = E/(f*lambda) = h/lambda, the standard QM result. h is small; this isn't much momentum. This is small enough so it isn't casually observable. Observed by Nichols and Hull (to about 10%, according to Bell and Green), and others since. Observed in special circumstances before and since (e.g., as contributor to comet tails). > The radiation pressure is not unlike electron spin, in that it is a > small effect that is difficult to notice and for me, difficult to > understand. Incidentally, the p=u/3 that I see in other sources is not > the equation you rely upon. The 1/3 is for omni-directional radiation, such as blackbody radiation. What is done experimentally usually uses a beam of some kind. For a plane wave, or a parallel (i.e., collimated) beam, p=P/c (or p=nP/c=P/v in a medium). For a focussed beam, it is a little less (and this difference is seen, and is essential to 3D trapping in optical tweezers). And of course, u=P/c. > and for me, difficult to > understand. You're not the first. Until Maxwell's calculation of electromagnetic radiation pressure, it was generally assuming that there was no radiation pressure, that no wave would exert a non-zero time-averaged force (since it has no mass). In the 1800s, the lack of observabed wave pressure was used as an argument for the wave theory of light and against corpuscular theories. One of the last works of the late Thomas Gold was a short note on solar sails and why they don't work. You are not alone. Maxwell's result (and Poynting's and Heaviside's) was specifically electromagnetic, so N. A. Umov's general result (not given the attention it deserves in the West) in 1874 was also a significant advance. Then Einstein in 1905 with E=mc^2. |