Speed of Light: A universal Constant?
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From: bz on 1 May 2005 21:48 H@..(Henri Wilson) wrote in news:3ana71tf044v5h60j0o175gneea06gms6e(a)4ax.com: > On Sun, 1 May 2005 03:18:35 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> > wrote: > >>H@..(Henri Wilson) wrote in >>news:ui3871p1te995gg3j0q79uftucsm8d5i65(a)4ax.com: >> >>> On Sat, 30 Apr 2005 00:15:23 +0000 (UTC), bz >>> <bz+sp(a)ch100-5.chem.lsu.edu> wrote: > >>>> >>>>If the transit time from detector 1 to detector 2 is constant, >>>>regardless of the speed / direction of rotation of the spinning >>>>source, AND the distance from detector1 to detector2 is sufficient for >>>>me to detect the variation in photon speed predicted by BaT, then BaT >>>>is invalidated. >>> >>> The stability of the timing system here is the big problem. >> >>It should be stable enough for the proposed experiment. >> >>> That's why I >>> use only ONE detector and two mirrors in my suggested configuration of >>> this experiment. >>> >>> spinning source ------------>Detector 1 >>> >>> The spinning spource has mirrors on both sides so one is approaching >>> and the other receding. >>> At 300 metres, the difference in arrival times will be about 10^-11 >>> seconds. So the pulse durations would not want to be much more than >>> this. >> >>I don't understand where your source is or the arrangement of your >>mirrors. >> >>If it is along a line that is at 90 degrees from the line from the >>mirror to detector 1, the only one mirror will send the beam to detector >>1, the other mirror will send the beam in the opposite direction from >>detector1. >> >>Could you explain? > > The two mirrors are facing the same way. They spin around centre c. > >|m > c > SO >|m > > The source is a continuous laser beam. The beam returns at c+2v. M1 (top mirror, approaching) and M2 (bottom mirror, receeding) are on opposite sides of the spinning disk. You need to split the beam from the source and send half of it to each mirror. If you have the angle of the mirrors set right, you can send both reflected beams toward a single detector. > As the speed of the rotation is increased, any difference in travel time > should be observable. I don't understand how the timing is going to be determined. How is the time or the speed of the photons determined? > The problem is to set the mirrors so that they are exactly opposite and > remain so at high rotations. > It should even be possible to make the mirrors slightly concave so as to > greatly increase the intensity of the spot. > This might work over 3000 metres or more....just. But it would probably > have to be done in space. >>> >>> Very difficult. >> >>space your arrival and departing mirrors 180 degrees apart. >> >>> >>> If you use two detectors, they still have to be capable of resolving >>> time differences of this magnitude. >> >>Again, each needs to be able to respond consistently. Neither needs to >>be able to resolve the small difference in time between the light >>hitting detector 1 and the light hitting detector 2. > > Then there is no point in having two detectors. The point is to measure the time it takes light to go from detector 1 to detector 2. We must have two detectors or play games with bouncing the light back to the same detector from another mirror and THAT would require a very fast detector and very stable optics. My experiment does away with many of those problems. ..... > > 'Suspecting' is not good enough. Do the sums. > > The circumference of a 6000 metre diameter circle is, say, 20000 metres. > You want to spin the mirrors at say 1000 rps. I am not spinning mirrors. I am spinning the laser's beam. > If the reflected spot There is no reflected spot. A typical laser specs at <1.2 mRad divergence. That will make the spot less than 1.2 meters at 1 km. We could use a green laser. http://www.laserglow.com/handheld.html 20 mW at 532 nm, 3.7e-19 Joules per photon. That gives 5.356E+16 photons per second at 20 mW. > is 1 cm width, the detectable energy is going to > be somewhat less that 10^-10 the source energy. 5.356e6 photons per second. Should be enough, shouldn't it? Heck we could probably get by with 2 mW, we would still have 5.3e5 photons per second. All we really need is a few photons per second. We will be sampling 1000 times per second. I really think we can do it. If we need more sensitivity, we can probably get a couple of 50 mm lenses (from an old pair of 8x50 binoculars) if we need to collect a few extra photons for some reason. >>> Again, even under the highest vacuums achievable on Earth, there might >>> be still enough gas in the tube to constitute an 'absolute' medium. >>> The experiment must be performed in deep space. >> >>But much of the intersteller media also has enough gas to meet your >>criteria of whatever an 'absolute' medium is. > > Maybe, maybe not. ..... > > It is worth reconsidering...just. > > >>>>> You don't want atmosphere or and fields of any description. >>>> >>>>You are now going to say that light has a constant velocity and BaT is >>>>invalid when there is an atmosphere or a field of any description? >>> >>> Look up the term 'extinction' as applied to light. >>> Light very rapidly changes speed in any transparent medium even a very >>> rare gas. I think Tom Roberts has stated that the extinction length in >>> normal air is around 3cms. >>> My H-aether theory suggests that there is a critical level of 'vacuum' >>> below which light is NOT significantly influenced by the presence of >>> matter. >> >>And what is that level? > > I don't know! > It's probably a bit like superconductivity. There is a fairly sudden > threshhold. > > >>> The MMX was supposed to measure our speed through the absolute aether. >>> It's null result ws interpreted in many ways. Few accepted that the >>> theory behind the experiment was completely wrong. >>> ther are plenty of people around today who still believe that an >>> absolute frame exists. >> >>True, there are. There are also people that think the earth is flat. >> >>> I certainly wouldn't rule out the possibility that 'local EM reference >>> frames' exist around large accumulations of matter. >> >>If so, the effects of the aether are very small. > > The effects of a 'local aether' would be exactly the same as SR. Didn't > you know that SR and LET maths are identical? I think this is the first time I have heard of LET. I though we were discussing absolute aether. ..... >>> Light MUST move at c wrt its source. >> >>we agree. >> >>> On emission it has no other >>> reference. Light from a remote star doesn't know where it is going to >>> end up. >> >>agreed. >> >>> How could its speed be determined by its eventual target? >> >>The speed isn't. > > Something determines the time it takes to travel from its source to > other places. What is that something? The distance. A moving source wrt the destination produces a different distance for each wave crest to travel. When we start to talk about photons, we have to realize that the distance between source and destination changed during the time that the EM field was going through one oscillation. This compresses or stretches the the length of the photon. When the EM field oscillates faster, it induces a stronger reaction in the detector, higher energy. Blue shifted. When the EM field oscillates slower, it induces a weaker reaction in the detector, lower energy. Red shifted. >>The frequency/wavelength is determined by the relative velocity of the >>target wrt the source. > > Irrelevant. That's true whatever theory you use. NO. BaT attributes the effect to the velocity of the source wrt the photon. Some BaT advocates say that the wavelength does NOT change, just the speed. >>> Variable star brightness curves now verify this point, ie, that light >>> travels through space at different speeds. >> >>We disagree. > > You haven't even looked. On the contrary. I even downloaded and ran your program. >>You have given a pretty strong argument that the photons get absorbed >>and re-emitted as they are passing through intersteller space. > > No they don't. Not in empty space at least...otherwise we would get > blurred images of galaxies. Huh??? We get blurred images here on earth because the atmospheric density changes (displacing the image) during the time that we are accumulating photons (taking a picture). Interstellar gases are unlikely to change density during a normal exposure time and thus unlikely to blur the images. >> >>Since the gasses that they pass through are NOT traveling at the same >>speed as the source, the photons can't be re-emitted with that speed. >> >>EITHER the photons have always been traveling at a constant speed wrt >>all observers or the photons are soon traveling at a constant speed wrt >>all observers. > > What are you saying? The gases they encounter during flight are not all > going to be at rest wrt the SRians on planet Earth. That is right. But they are all also not going to be systematically in motion wrt the source. So any velocity gained/lost due to motion of the source would soon be lost. >>The only 'reminder' that they carry with them as to the velocity of the >>source wrt the light emitted is the frequency/wavelength that they >>originally had. > > Which can only be specified in relation to the speed wrt their source. Right. But they will be moving at c, not at c+v. -- bz please pardon my infinite ignorance, the set-of-things-I-do-not-know is an infinite set. bz+sp(a)ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap
From: Bilge on 2 May 2005 05:48 bz: >My idea has been evolving since I first proposed using a police lidar and >a spinning fan and looking at the doppler shift along with the actual >velocity of the reflected photons. > >Now, a laser beam is conducted from a laser at the center of a spinning >disk to the edge by an optical fiber (protect laser from high G.), launch >laser beam tangential to edge of disk (possible multiple beam). > >Time beam as it passes between two detectors. Detectors separated by >'significant distance'. > >Spin disk at various rpm in both clockwise and ccw directions. >look for variation in time of flight of the photons. I hate to say it, but there's no way you will be able to resolve that difference. For the sake of argument, though, first look at the equipment that you would need: several constant fraction discriminators and a time to amplitude convertor. You need the CFDs to insure the timing of signals is independent of any rise times in the system. Ypu would then use the output of the CFDs to start and stop the TAC, which gives you an output pulse with an amplitude that's proportional to start time - stoptime. But even that won't give you 1 ps timing. That's why experiments that have tried to determine flight times for light paths are done using interference. >I figure we can get more than 600 mph in both directions. >We should see more than plus and minus 1 pico second difference in TOFLS >(time of flight light speed) IF BaT works and our path length is 1 km. If >we don't see a difference, BaT is invalidated. Henri's cartoon theory has already been invalidated - by a century of experiments. He's pulling your chain. Again, for the sake of argument, you were able to perform the experiment and ``prove'' to henri that his stupid cartoon idea is wrong. It's of no consequence. Within an hour, he'd have a new cartoon idea that has also been invalidated by a century's worth of experimental data, but which he'd have some new lame excuse that only a special experiment that hasn't been done can be used to test his cartoon. Henri is a pathetic luser who knows zero about physics and has no interest in learning anything about physics. In fact, he can't find one newsgroup out of more than 30,000 in which he could contribute anything. He appears to have nothing better to do than waste his time posting what he knows to be garbage in an attempt to waste other people's time.
From: Henri Wilson on 2 May 2005 05:57 On Mon, 2 May 2005 01:48:59 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> wrote: >H@..(Henri Wilson) wrote in >news:3ana71tf044v5h60j0o175gneea06gms6e(a)4ax.com: > >>>If it is along a line that is at 90 degrees from the line from the >>>mirror to detector 1, the only one mirror will send the beam to detector >>>1, the other mirror will send the beam in the opposite direction from >>>detector1. >>> >>>Could you explain? >> >> The two mirrors are facing the same way. They spin around centre c. >> >>|m >> c SO >>|m >> >> The source is a continuous laser beam. The beam returns at c+2v. > >M1 (top mirror, approaching) and M2 (bottom mirror, receeding) are on >opposite sides of the spinning disk. > >You need to split the beam from the source and send half of it to each >mirror. > >If you have the angle of the mirrors set right, you can send both >reflected beams toward a single detector. Maybe my diagram didn't come out properly. I have fixed it (above). At 1km, the laser beam will diverge sufficiently to encompass both mirrors. It is then reflected back at c+2v and c-2v from both sides. Get it now? > >> As the speed of the rotation is increased, any difference in travel time >> should be observable. > >I don't understand how the timing is going to be determined. >How is the time or the speed of the photons determined? The BaT predicts that the two reflected pulses will arrive back at the source observer 'O', at slightly different times. As te rotation is increased, the gap between hte pulses should widen, as seen on a CRO. > >> The problem is to set the mirrors so that they are exactly opposite and >> remain so at high rotations. >> It should even be possible to make the mirrors slightly concave so as to >> greatly increase the intensity of the spot. >> This might work over 3000 metres or more....just. But it would probably >> have to be done in space. > >>>> >>>> Very difficult. >>> >>>space your arrival and departing mirrors 180 degrees apart. >>> >>>> >>>> If you use two detectors, they still have to be capable of resolving >>>> time differences of this magnitude. >>> >>>Again, each needs to be able to respond consistently. Neither needs to >>>be able to resolve the small difference in time between the light >>>hitting detector 1 and the light hitting detector 2. >> >> Then there is no point in having two detectors. > >The point is to measure the time it takes light to go from detector 1 to >detector 2. No you are introducing unnecessary complications. You only need one detector. > >We must have two detectors or play games with bouncing the light back to >the same detector from another mirror and THAT would require a very fast >detector and very stable optics. Correct...although there are no complicated optics....just a singe lens. The signals are likely to be only about 10^-10 secs apart. Maximizing the distance is an obvious requirement...but as distance is increased, for a particular rotation speed, the intensity of the spot decreases by the cube of the distance. Can you see why? > >My experiment does away with many of those problems. You are trying to measure the time taken for the c+v pulse to travel between the two detectors then in a separate experiment, measure the time for the c-v pulse to do the same. You cannot hope to achieve mirror speeds of more than about 3000 m/sec or 10^-5c. If the distance between your detectors is say 3000 metres, the travel time at 'c' is 10^-5 secs. So you are trying to measure a difference of 2 parts in 10^5 between two time intervals of approximately 10^-5 seconds. that is a pretty hopeless task. In my single detector version, all that you have to do is synched the CRO trace with the rotation frequency and look for two blips on it rather than one. They should separate as the frequency increases. >.... >> >> 'Suspecting' is not good enough. Do the sums. >> >> The circumference of a 6000 metre diameter circle is, say, 20000 metres. >> You want to spin the mirrors at say 1000 rps. > >I am not spinning mirrors. I am spinning the laser's beam. Same thing. > >> If the reflected spot > >There is no reflected spot. > >A typical laser specs at <1.2 mRad divergence. >That will make the spot less than 1.2 meters at 1 km. > >We could use a green laser. http://www.laserglow.com/handheld.html >20 mW at 532 nm, 3.7e-19 Joules per photon. > >That gives 5.356E+16 photons per second at 20 mW. > >> is 1 cm width, the detectable energy is going to >> be somewhat less that 10^-10 the source energy. > >5.356e6 photons per second. Should be enough, shouldn't it? >Heck we could probably get by with 2 mW, we would still have 5.3e5 photons >per second. It depends on the distance. Like I said, the spot intensity decreases with the CUBE of the distance. > >All we really need is a few photons per second. We will be sampling 1000 >times per second. I really think we can do it. I don't > >If we need more sensitivity, we can probably get a couple of 50 mm lenses >(from an old pair of 8x50 binoculars) if we need to collect a few extra >photons for some reason. NASA can probably afford that. > >>>> Again, even under the highest vacuums achievable on Earth, there might >>>> be still enough gas in the tube to constitute an 'absolute' medium. >>>> The experiment must be performed in deep space. >>> >>>But much of the intersteller media also has enough gas to meet your >>>criteria of whatever an 'absolute' medium is. >> >> Maybe, maybe not. >.... >> >> It is worth reconsidering...just. >> >> >>>>>> You don't want atmosphere or and fields of any description. >>>>> >>>>>You are now going to say that light has a constant velocity and BaT is >>>>>invalid when there is an atmosphere or a field of any description? >>>> >>>> Look up the term 'extinction' as applied to light. >>>> Light very rapidly changes speed in any transparent medium even a very >>>> rare gas. I think Tom Roberts has stated that the extinction length in >>>> normal air is around 3cms. >>>> My H-aether theory suggests that there is a critical level of 'vacuum' >>>> below which light is NOT significantly influenced by the presence of >>>> matter. >>> >>>And what is that level? >> >> I don't know! >> It's probably a bit like superconductivity. There is a fairly sudden >> threshhold. >> >> >>>> The MMX was supposed to measure our speed through the absolute aether. >>>> It's null result ws interpreted in many ways. Few accepted that the >>>> theory behind the experiment was completely wrong. >>>> ther are plenty of people around today who still believe that an >>>> absolute frame exists. >>> >>>True, there are. There are also people that think the earth is flat. >>> >>>> I certainly wouldn't rule out the possibility that 'local EM reference >>>> frames' exist around large accumulations of matter. >>> >>>If so, the effects of the aether are very small. >> >> The effects of a 'local aether' would be exactly the same as SR. Didn't >> you know that SR and LET maths are identical? > >I think this is the first time I have heard of LET. I though we were >discussing absolute aether. Lorentz Ether Theory. That is the main one. It lead to SR. It is really the same as SR but Einstein cleverly disguised the fact. > >.... >>>> Light MUST move at c wrt its source. >>> >>>we agree. >>> >>>> On emission it has no other >>>> reference. Light from a remote star doesn't know where it is going to >>>> end up. >>> >>>agreed. >>> >>>> How could its speed be determined by its eventual target? >>> >>>The speed isn't. >> >> Something determines the time it takes to travel from its source to >> other places. What is that something? > >The distance. A moving source wrt the destination produces a different >distance for each wave crest to travel. No, that works for sound in air and possibly for light in a medium. But there is NO medium in this situation. > >When we start to talk about photons, we have to realize that the distance >between source and destination changed during the time that the EM field >was going through one oscillation. This compresses or stretches the the >length of the photon. How can 'eventual target movement' affect the physical distance between 'wavecrests' of a remote beam of light. Do you think it changes every time the target moves.... it might be a billion lightyears away. > >When the EM field oscillates faster, it induces a stronger reaction in the >detector, higher energy. Blue shifted. When the EM field oscillates >slower, it induces a weaker reaction in the detector, lower energy. Red >shifted. That's just doppler theory. We know all about that. It is about the same for SR, LET and the BaT at low speeds. >>>The frequency/wavelength is determined by the relative velocity of the >>>target wrt the source. >> >> Irrelevant. That's true whatever theory you use. > >NO. BaT attributes the effect to the velocity of the source wrt the >photon. Some BaT advocates say that the wavelength does NOT change, just >the speed. Read above. How could the wavelength be affected by all the possible eventual targets in the universe? Light has no idea what it is going to hit when it is being emitted. It has only one reference, its source. Its speed is c wrt that source. The wavelengths associated with any particular energy transition are the same in the frames of the respective sources. The true physical spacing between 'wavecrests' is not affected by any observer. > >>>> Variable star brightness curves now verify this point, ie, that light >>>> travels through space at different speeds. >>> >>>We disagree. >> >> You haven't even looked. > >On the contrary. I even downloaded and ran your program. The curves are generally very similar to the majority of observed curves. I gave you a list to look at. The program takes time to master. It is very comprehensive. > >>>You have given a pretty strong argument that the photons get absorbed >>>and re-emitted as they are passing through intersteller space. >> >> No they don't. Not in empty space at least...otherwise we would get >> blurred images of galaxies. > >Huh??? We get blurred images here on earth because the atmospheric density >changes (displacing the image) during the time that we are accumulating >photons (taking a picture). Not from the HST. that's why it is up there. > >Interstellar gases are unlikely to change density during a normal exposure >time and thus unlikely to blur the images. Photons are not likely to be 'absorbed and re-emitted' when there is only one molecule per m3 either. > >>> >>>Since the gasses that they pass through are NOT traveling at the same >>>speed as the source, the photons can't be re-emitted with that speed. >>> >>>EITHER the photons have always been traveling at a constant speed wrt >>>all observers or the photons are soon traveling at a constant speed wrt >>>all observers. >> >> What are you saying? The gases they encounter during flight are not all >> going to be at rest wrt the SRians on planet Earth. > >That is right. But they are all also not going to be systematically in >motion wrt the source. So any velocity gained/lost due to motion of the >source would soon be lost. Gas clouds will be randomly in motion wrt the source. They could either speed up the light or slow it down. What I cannot explain is how light could revert to its original speed after leaving a gas cloud as it does, eg, at a glass/air interface. Their refractive indices are going to be very close to unity in space because the gas densities are so low. > >>>The only 'reminder' that they carry with them as to the velocity of the >>>source wrt the light emitted is the frequency/wavelength that they >>>originally had. >> >> Which can only be specified in relation to the speed wrt their source. > >Right. But they will be moving at c, not at c+v. They are moving at c+v wrt the target. They only have ONE speed and don't know what their eventual target will be. HW. www.users.bigpond.com/hewn/index.htm Sometimes I feel like a complete failure. The most useful thing I have ever done is prove Einstein wrong.
From: YBM on 2 May 2005 07:59 Henri Wilson a ýcrit : > On Mon, 02 May 2005 04:17:19 +0200, YBM <ybmess(a)nooos.fr> wrote: > please contribute something intelligent or remain silent. I did try to teach you something about computing... It ended up as an impossible task.
From: bz on 2 May 2005 09:36
H@..(Henri Wilson) wrote in news:6lqb71ld557n8oeh66j8tchl5mnqam7a89(a)4ax.com: > On Mon, 2 May 2005 01:48:59 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> > wrote: > >>H@..(Henri Wilson) wrote in >>news:3ana71tf044v5h60j0o175gneea06gms6e(a)4ax.com: >> > >>>>If it is along a line that is at 90 degrees from the line from the >>>>mirror to detector 1, the only one mirror will send the beam to >>>>detector 1, the other mirror will send the beam in the opposite >>>>direction from detector1. >>>> >>>>Could you explain? >>> >>> The two mirrors are facing the same way. They spin around centre c. >>> >>>|m >>> c >>> SO >>>|m >>> >>> The source is a continuous laser beam. The beam returns at c+2v. >> >>M1 (top mirror, approaching) and M2 (bottom mirror, receeding) are on >>opposite sides of the spinning disk. >> >>You need to split the beam from the source and send half of it to each >>mirror. >> >>If you have the angle of the mirrors set right, you can send both >>reflected beams toward a single detector. > > Maybe my diagram didn't come out properly. > I have fixed it (above). > > At 1km, the laser beam will diverge sufficiently to encompass both > mirrors. Agreed. > > It is then reflected back at c+2v and c-2v from both sides. > > Get it now? I understand the reflections now. >>> As the speed of the rotation is increased, any difference in travel >>> time should be observable. >> >>I don't understand how the timing is going to be determined. >>How is the time or the speed of the photons determined? > > The BaT predicts that the two reflected pulses will arrive back at the > source observer 'O', at slightly different times. As te rotation is > increased, the gap between hte pulses should widen, as seen on a CRO. I think that we need to look at how the reflected beams will travel during the time that the mirrors are almost correctly aligned. It still isn't clear to me that the difference in arrival times of the two beams is going to give us any information about the speed of the light. ..... >>>>Again, each needs to be able to respond consistently. Neither needs to >>>>be able to resolve the small difference in time between the light >>>>hitting detector 1 and the light hitting detector 2. >>> >>> Then there is no point in having two detectors. >> >>The point is to measure the time it takes light to go from detector 1 to >>detector 2. > > No you are introducing unnecessary complications. You only need one > detector. You can use two rotating mirrors, one detector. I will use two fixed detectors, no rotating mirrors? OK >>We must have two detectors or play games with bouncing the light back to >>the same detector from another mirror and THAT would require a very fast >>detector and very stable optics. > > Correct...although there are no complicated optics....just a singe lens. > > The signals are likely to be only about 10^-10 secs apart. Maximizing > the distance is an obvious requirement...but as distance is increased, > for a particular rotation speed, the intensity of the spot decreases by > the cube of the distance. > Can you see why? Our response is based on photons per detector area. The area of a sphere increases as the square of the radius. This is why light, etc decrease as the square of the distance. The intensity of the spot should follow inverse square law. If we were filling space with the energy and measuring the photons per unit volume, the decrease would go as the volume of the sphere, which is cubic. > >> >>My experiment does away with many of those problems. > > You are trying to measure the time taken for the c+v pulse to travel > between the two detectors then in a separate experiment, measure the > time for the c-v pulse to do the same. > You cannot hope to achieve mirror speeds of more than about 3000 m/sec > or 10^-5c. > If the distance between your detectors is say 3000 metres, the travel > time at 'c' is 10^-5 secs. > So you are trying to measure a difference of 2 parts in 10^5 between two > time intervals of approximately 10^-5 seconds. That is 10 microseconds. Measuring such things is easy. > > that is a pretty hopeless task. Here is some CHEAP data collection hardware/software: http://www.picotech.com/picoscope-3000.pdf 10 Giga Samples per second sampling rate for the 800 POUNDS STERLING version. > In my single detector version, all that you have to do is synched the > CRO trace with the rotation frequency and look for two blips on it > rather than one. They should separate as the frequency increases. They are separated by time due to angular displacement which is dependent on angular rotation velocity, mirror alignment, and perhaps the c+v, c-v. I am not 100 percent sure that will work. The G forces and how they act on the mirrors will serve to confuse things. I am not sure that there is any way to make sure which effect is causing the blips to shift. In my experiment, those problems are removed. ..... >>> 'Suspecting' is not good enough. Do the sums. >>> >>> The circumference of a 6000 metre diameter circle is, say, 20000 >>> metres. You want to spin the mirrors at say 1000 rps. >> >>I am not spinning mirrors. I am spinning the laser's beam. > > Same thing. Not at all. You have c+2v, I have c+v. You have g forces distorting the position of the mirrors, I avoid that problem. > >> >>> If the reflected spot >> >>There is no reflected spot. >> >>A typical laser specs at <1.2 mRad divergence. >>That will make the spot less than 1.2 meters at 1 km. >> >>We could use a green laser. http://www.laserglow.com/handheld.html >>20 mW at 532 nm, 3.7e-19 Joules per photon. >> >>That gives 5.356E+16 photons per second at 20 mW. >> >>> is 1 cm width, the detectable energy is going to >>> be somewhat less that 10^-10 the source energy. >> >>5.356e6 photons per second. Should be enough, shouldn't it? >>Heck we could probably get by with 2 mW, we would still have 5.3e5 >>photons per second. > > It depends on the distance. Like I said, the spot intensity decreases > with the CUBE of the distance. Everything I can find shows light decreasing as the inverse of the square of the distance. Where do you get your cubic factor? > >> >>All we really need is a few photons per second. We will be sampling 1000 >>times per second. I really think we can do it. > > I don't > ..... >>>>> Light MUST move at c wrt its source. >>>> >>>>we agree. >>>> >>>>> On emission it has no other >>>>> reference. Light from a remote star doesn't know where it is going >>>>> to end up. >>>> >>>>agreed. >>>> >>>>> How could its speed be determined by its eventual target? >>>> >>>>The speed isn't. >>> >>> Something determines the time it takes to travel from its source to >>> other places. What is that something? >> >>The distance. A moving source wrt the destination produces a different >>distance for each wave crest to travel. > > No, that works for sound in air and possibly for light in a medium. > > But there is NO medium in this situation. I don't see anything in the above that REQUIRES media. >>When we start to talk about photons, we have to realize that the >>distance between source and destination changed during the time that the >>EM field was going through one oscillation. This compresses or stretches >>the the length of the photon. > > How can 'eventual target movement' affect the physical distance between > 'wavecrests' of a remote beam of light. > > Do you think it changes every time the target moves.... it might be a > billion lightyears away. The change takes place AT THE TARGET. >> >>When the EM field oscillates faster, it induces a stronger reaction in >>the detector, higher energy. Blue shifted. When the EM field oscillates >>slower, it induces a weaker reaction in the detector, lower energy. Red >>shifted. > > That's just doppler theory. We know all about that. It is about the same > for SR, LET and the BaT at low speeds. right. >>>>The frequency/wavelength is determined by the relative velocity of the >>>>target wrt the source. >>> >>> Irrelevant. That's true whatever theory you use. >> >>NO. BaT attributes the effect to the velocity of the source wrt the >>photon. Some BaT advocates say that the wavelength does NOT change, just >>the speed. > > Read above. How could the wavelength be affected by all the possible > eventual targets in the universe? Each target sees the wavelength that is determined by its velocity wrt the source. > Light has no idea what it is going to hit when it is being emitted. It > has only one reference, its source. Its speed is c wrt that source. The > wavelengths associated with any particular energy transition are the > same in the frames of the respective sources. true. > > The true physical spacing between 'wavecrests' is not affected by any > observer. That is like saying that there is an absolute frame of reference or an absolute velocity. The 'true physical spacing' can only be observed by observers that are at rest wrt the absolute frame of reference of the universe. Since no such frame exists and all observers are 'in motion' wrt other observers, there is no 'true physical spacing between 'wavecrests'. All are relative, relating the source and the observer. > >> >>>>> Variable star brightness curves now verify this point, ie, that >>>>> light travels through space at different speeds. >>>> >>>>We disagree. >>> >>> You haven't even looked. >> >>On the contrary. I even downloaded and ran your program. > > The curves are generally very similar to the majority of observed > curves. I gave you a list to look at. > > The program takes time to master. It is very comprehensive. > >> >>>>You have given a pretty strong argument that the photons get absorbed >>>>and re-emitted as they are passing through intersteller space. >>> >>> No they don't. Not in empty space at least...otherwise we would get >>> blurred images of galaxies. >> >>Huh??? We get blurred images here on earth because the atmospheric >>density changes (displacing the image) during the time that we are >>accumulating photons (taking a picture). > > Not from the HST. that's why it is up there. > >> >>Interstellar gases are unlikely to change density during a normal >>exposure time and thus unlikely to blur the images. > > Photons are not likely to be 'absorbed and re-emitted' when there is > only one molecule per m3 either. How many cubic meters must a photon transit at that density before it probably encounters a friendly molecule? Lets see. 2 grams of hydrogen is one mole, occupies 22.4 ltr at 1 atm. That is 6.023e23 moles of hydrogen. A m3 contains 1000 ltrs. That gives about 1.349E+28 molecules in a cubic meter of Hydrogen gas at STP. So we line up 1.349E28 meters and our light has, in effect, just passed through hydrogen at STP. That is 1.426e12 light years. A bit bigger than the universe. Of course, the estimate I have seen is for interstellar space is one molecule per cubic cm. A million times denser than your figure. THAT would bring the distance down to 1.4e6 light years. MANY stars are further away from us. >>>>Since the gasses that they pass through are NOT traveling at the same >>>>speed as the source, the photons can't be re-emitted with that speed. >>>> >>>>EITHER the photons have always been traveling at a constant speed wrt >>>>all observers or the photons are soon traveling at a constant speed >>>>wrt all observers. >>> >>> What are you saying? The gases they encounter during flight are not >>> all going to be at rest wrt the SRians on planet Earth. >> >>That is right. But they are all also not going to be systematically in >>motion wrt the source. So any velocity gained/lost due to motion of the >>source would soon be lost. > > Gas clouds will be randomly in motion wrt the source. They could either > speed up the light or slow it down. What I cannot explain is how light > could revert to its original speed after leaving a gas cloud as it does, > eg, at a glass/air interface. > Their refractive indices are going to be very close to unity in space > because the gas densities are so low. > >> >>>>The only 'reminder' that they carry with them as to the velocity of >>>>the source wrt the light emitted is the frequency/wavelength that they >>>>originally had. >>> >>> Which can only be specified in relation to the speed wrt their source. >> >>Right. But they will be moving at c, not at c+v. > > They are moving at c+v wrt the target. We obviously disagree on that point. > They only have ONE speed and don't know what their eventual target will > be. They don't need to know that until they hit the target. At that moment, the energy/wavelength is clear. -- bz please pardon my infinite ignorance, the set-of-things-I-do-not-know is an infinite set. bz+sp(a)ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap |