Speed of Light: A universal Constant?
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From: Henri Wilson on 3 May 2005 00:19 On Mon, 2 May 2005 22:56:24 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> wrote: >H@..(Henri Wilson) wrote in >news:v7ad71pae4docs5vg9o8h93cokkdvt5i1a(a)4ax.com: > >> S__p->__c-----------------------------------------A >> >> A source S sends a pulse of light towards Andromeda. >> Connected to the source is a long rod with a clock on the end. >> >> The clock registers a time when the pulse passes by. >> > >You didn't ask me, but I will answer. > >> are you one of those people who believes the clock >> will register an infinite number of readings so as to accommodate the >> nonsensical SRian claim that the pulse is moving at the same speed wrt >> every object in Andromeda? > >If there is a rigid rod, then the clock at the end must be at rest wrt the >source. > >Are we to assume the clock is sync'd with the clock at the source? That doesn't matter. > >If so, the clock clock can only register 1 time and that is going to be the >time it takes light to travel the length of the rod at c. Don't worry about the actual time. The point is, IT REGISTERS ONLY ONE TIME. The pulse has only one speed. THEREFORE IT CANNOT BE TRAVELING AT THE SAME SPEED WRT EVERY DIFFERENTLY MOVING OBJECT IN ANDROMEDA. Is that clear now? It couldn't be any clearer. > >The observers in andromeda will each observe the pulse (assuming it spreads >wide enough) as traveling at c. Each will measure the photon energy of the >pulse as what would be appropriate considering their relative velocity wrt >the source. I don't give a hoot what you claim about observers in Andromeda. You are merely quoting an unproven postulate, which is totally irrelevant here. 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: Henri Wilson on 3 May 2005 00:48 On Tue, 3 May 2005 02:04:20 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> wrote: >H@..(Henri Wilson) wrote in >news:i5cd71tp79n5atrotfacm8dm2s08jg5j48(a)4ax.com: > >> On Mon, 2 May 2005 13:36:36 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> >> wrote: >> >>>H@..(Henri Wilson) wrote in >>>news:6lqb71ld557n8oeh66j8tchl5mnqam7a89(a)4ax.com: >.... > >Lets get an accurage result. BTW, if the mirror were continuous and >properly balanced, I don't think the G forces would distort it >significantly. > >Also, I saw a storage device using a light weight flywheel that spins at >100,000 rpm and has an edge velocity of 1000 m/s, so we can get higher >speeds than I initially thought. >. >>>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. >> >> No you don't. The laser mountings are just as likely to be distorted. > >My laser is mounted at the center (it might even be mounted off of the disk >entirely) and the output is guided to the edge of the disk via fiber >optics. > >The fiber at the edge will be aligned to launch the laser beam tangential >to the edge of the disk and will be firmly glued in place. Pretty good glue. > >The mass of a light fiber is very low, the G forces are not going to have >much effect, at all. It is just as practical to glue a couple of mirrors onto it. Balance is critical of course. > >.... >>>> But there is NO medium in this situation. >>> >>>I don't see anything in the above that REQUIRES media. >> >> You are claiming that property of space between any two points >> determines light speed between those points. >> That is straight aether theory. >> Space has no absolute properties. > >That is beside the point. As long as the travel time from detector 1 to >detector 2 is constant and independent of source speed, BaT is invalidated. >On the other hand, if travel time decreases with blue shift (approach) and >increases with red shift (retreat) then SR is invalidated and BaT rules. Of course. That's what we are looking for. > >.... >>>> Do you think it changes every time the target moves.... it might be a >>>> billion lightyears away. >>> >>>The change takes place AT THE TARGET. >> >> That's the BaT concept. Good!! You are starting to see the light. > >I thought Bat sait the change takes place at the source ONLY. No. Wavelength, frequency and speed are all measured in the source frame. > >>>>>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. >>> >>>> 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. >> >> What a target 'sees' is not what matters. >> The point is, nothing physically changes because of anything an observer >> does. > >So, If I (an observer) take a space ship toward the nearest star and >accelerate at a constant 1 G (I have plenty of fuel). I don't see any blue >shift in the light from the stars I am approaching? I don't see any red >shift in light from our sun? Of course you do. The speed of the light relative to you is increasing or decreasing so the 'wavecrests' pass you at different rates. But the light doesn't change in any way simply because you are looking at it! >>>> 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'. >> >> Here's an experiment. > >Lets try this one first. A satellite is in orbit around the earth. >There are uplink and downlink frequencies used in communications with the >satellite. If your contention were true, the uplink would show no doppler >shift, the downlink would show doppler shift. > >Why, then why it necessary to compensate for doppler shift of the downlink >AND the uplink frequencies? >[quote from http://services.eng.uts.edu.au/ >~samr/AjThoms/crcss/articles/IAC99_Paper.pdf] >.... >Frequency Tracking Requirements >The maximum Doppler shifts of the signals are +662.1 kHz for the 30 GHz >uplink frequency and +441.4 kHz for the 20 GHz downlink frequency. >Additionally, there will be large frequency errors from the transmit and >receive earth station local oscillators and from the spacecraft local >oscillators. The rapidly changing Doppler shift and slowly varying >oscillator drifts are accommodated by the utilisation of a frequency >acquisition and tracking algorithm. >[unquote] > > That's about doppler shift due to movement. It has nothing to do with GR. >> A source sends pulses of EM in a particular direction. >> Detween each pulse, it also fires a rigid rod, the ends of which are >> adjacent to the pulses. > >I assume the rigid rods travel at the same speed as the pulses. Magic rods >with no mass so they can travel at C. Aything can travel at any speed relative to anything else...if you can find enough energy to get it there. The reason few things in the universe are moving very quickly wrt other objects is pure and simple. It is like a gas at 2.7K. It is very difficult to accelerate anything to near c wrt its original state. > >> >> Do you sincerely believe that these rods change length every time a >> different observer looks at them? > >Only if the different observer is at a different velocity relative to the >source. There is no connection between the observer and the light as it travels. I am talking about an 'intrinsic' change in the light. > >>>All are relative, relating the source and the observer. >> >> Contrary to what SRians believe, physics is not just about measurement. >> Physics is also about the realization that the universe doesn't depend >> on human perception for its existence. The Earth functioned quite well, >> over time and space, without human observers. > >when I say observer, I am not talking about something alive. It could be an >atom or a molecule or a PM tube or a coat of paint. > >Anything that will absorb a photon. It doesn't even have to absorb anything. It can be a potential observer. > >>>>>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. >> >> This is all speculation. > >Speculation? What is speculative about it? >Do you see an error in my calculations or the reasoning behind them? You will find all kinds of figures for the density of space. >.... >>>> 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. >> >> So you think they don't possess energy and wavelength until they hit >> something? > >I think that they get some energy from the radiation frequency, add or >subtract energy for the velocity of the source, and, finally add or >subtract more energy for the velocity of the target. > >You can even measure the gain or loss of KE of the source/target due to the >radiation/absorbtion of the photon. Look, there is only one way you can make meaningful statements about ,eg, the H alpha line photon. It has a certain energy and wavelength in its source frame. All similar photons have the same properties in their respective source frames. Why would anyone want to make claims about its properties in any arbitrary frame. It would be totally useless. > >> What properties are possessed by photons then? > >Spin, angular momentum, frequency, energy, polarity, and velocity. > >Speed is always c. wrt its source. >Rest mass is always zero. maybe..but debatable. What constitutes mass. 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: Henri Wilson on 3 May 2005 00:50 On Tue, 03 May 2005 03:58:59 +0200, YBM <ybmess(a)nooos.fr> wrote: >Henri Wilson a ýcrit : >> My programs work and do what I want them to do. > >You're right : when they didn't crash they illustrate how >and why you don't understand SR. > >> I'm not trying to get a job as >> a programmer. > >Unfortunately you could, the computer industry is full >of bad programers. You would be one of them. 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: bz on 3 May 2005 04:23 H@..(Henri Wilson) wrote in news:25vd71t3tmebj977tft966i2i7am3vok1v(a)4ax.com: > On Tue, 3 May 2005 02:04:20 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> > wrote: > >>H@..(Henri Wilson) wrote in >>news:i5cd71tp79n5atrotfacm8dm2s08jg5j48(a)4ax.com: >> >>> On Mon, 2 May 2005 13:36:36 +0000 (UTC), bz >>> <bz+sp(a)ch100-5.chem.lsu.edu> wrote: >>> >>>>H@..(Henri Wilson) wrote in >>>>news:6lqb71ld557n8oeh66j8tchl5mnqam7a89(a)4ax.com: ..... >>My laser is mounted at the center (it might even be mounted off of the >>disk entirely) and the output is guided to the edge of the disk via >>fiber optics. >> >>The fiber at the edge will be aligned to launch the laser beam >>tangential to the edge of the disk and will be firmly glued in place. > > Pretty good glue. An epoxy. The same thing that holds together the carbon fibers of the disk itself. >>The mass of a light fiber is very low, the G forces are not going to >>have much effect, at all. > > It is just as practical to glue a couple of mirrors onto it. > Balance is critical of course. Any useful mirror will be much more massive that an optical fiber. Have you ever played with fiber optics? ..... >>That is beside the point. As long as the travel time from detector 1 to >>detector 2 is constant and independent of source speed, BaT is >>invalidated. On the other hand, if travel time decreases with blue shift >>(approach) and increases with red shift (retreat) then SR is invalidated >>and BaT rules. > > Of course. That's what we are looking for. good, we are agreed on this. >>>>> Do you think it changes every time the target moves.... it might be >>>>> a billion lightyears away. >>>> >>>>The change takes place AT THE TARGET. >>> >>> That's the BaT concept. Good!! You are starting to see the light. >> >>I thought Bat said the change takes place at the source ONLY. > > No. Wavelength, frequency and speed are all measured in the source > frame. We can measure them in any frame but everything except the speed will be different in different frames. ..... >>> What a target 'sees' is not what matters. >>> The point is, nothing physically changes because of anything an >>> observer does. >> >>So, If I (an observer) take a space ship toward the nearest star and >>accelerate at a constant 1 G (I have plenty of fuel). I don't see any >>blue shift in the light from the stars I am approaching? I don't see any >>red shift in light from our sun? > > Of course you do. > The speed of the light relative to you is increasing or decreasing so > the 'wavecrests' pass you at different rates. > > But the light doesn't change in any way simply because you are looking > at it! Correct. But saying 'the light doesn't change in any way' could be taken to say 'the light will look the same in every way as it would if I were at rest'. However when I measure the energy, it will be different. The frequency I measure will be different. The wavelength I measure will be different. But the speed with still be c. ..... >>>>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'. >>> >>> Here's an experiment. >> >>Lets try this one first. A satellite is in orbit around the earth. >>There are uplink and downlink frequencies used in communications with >>the satellite. If your contention were true, the uplink would show no >>doppler shift, the downlink would show doppler shift. >> >>Why, then why it necessary to compensate for doppler shift of the >>downlink AND the uplink frequencies? >>[quote from http://services.eng.uts.edu.au/ >>~samr/AjThoms/crcss/articles/IAC99_Paper.pdf] >>.... >>Frequency Tracking Requirements >>The maximum Doppler shifts of the signals are +662.1 kHz for the 30 GHz >>uplink frequency and +441.4 kHz for the 20 GHz downlink frequency. >>Additionally, there will be large frequency errors from the transmit and >>receive earth station local oscillators and from the spacecraft local >>oscillators. The rapidly changing Doppler shift and slowly varying >>oscillator drifts are accommodated by the utilisation of a frequency >>acquisition and tracking algorithm. >>[unquote] > > That's about doppler shift due to movement. It has nothing to do with > GR. I have been understanding you [or some other BaT advocates] as saying that ALL doppler shift is due to c'=c+/-v. And I understood you as saying that the shift all takes place at the source, none at the observer. Have you changed your mind or did I misapprehend you? >>> A source sends pulses of EM in a particular direction. >>> Detween each pulse, it also fires a rigid rod, the ends of which are >>> adjacent to the pulses. >> >>I assume the rigid rods travel at the same speed as the pulses. Magic >>rods with no mass so they can travel at C. > > Aything can travel at any speed relative to anything else...if you can > find enough energy to get it there. There doesn't appear to be enough energy in the universe to move anything with rest mass at c wrt anything in the universe. > The reason few things in the universe are moving very quickly wrt other > objects is pure and simple. It is like a gas at 2.7K. It is very > difficult to accelerate anything to near c wrt its original state. or wrt any other state. ...... >>> Do you sincerely believe that these rods change length every time a >>> different observer looks at them? >> >>Only if the different observer is at a different velocity relative to >>the source. > > There is no connection between the observer and the light as it travels. > I am talking about an 'intrinsic' change in the light. And what 'intrinsic' properties does light have? I assume'intrinsic' means a property that is NOT source or destination dependent. Speed, spin (?), angular momentum, rest mass. Those are 'intrinsic' properties. I don't know of any others. ..... >>when I say observer, I am not talking about something alive. It could be >>an atom or a molecule or a PM tube or a coat of paint. >> >>Anything that will absorb a photon. > > It doesn't even have to absorb anything. It can be a potential observer. Agreed. >>>>>>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. >>> >>> This is all speculation. >> >>Speculation? What is speculative about it? >>Do you see an error in my calculations or the reasoning behind them? > > You will find all kinds of figures for the density of space. I used your figure for the first set of calculations. I used another estimate for the second. There should be some the lower and upper limits for concentration of molecules in 'clear' space. I showed that if the concentration is 1 molecule per cc, then the effect on the light of traveling 1.4 million light years would be the same as traveling through 1 meter of hydrogen at STP. >>>>> 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. >>> >>> So you think they don't possess energy and wavelength until they hit >>> something? >> >>I think that they get some energy from the radiation frequency, add or >>subtract energy for the velocity of the source, and, finally add or >>subtract more energy for the velocity of the target. >> >>You can even measure the gain or loss of KE of the source/target due to >>the radiation/absorbtion of the photon. > > Look, there is only one way you can make meaningful statements about > ,eg, the H alpha line photon. There is more than one way to make meaningul statements but I agree with your next line: > It has a certain energy and wavelength in its source frame. Agreed. AND I say that the photon will be found to be traveling at c wrt any observer's frame of reference. If that frame is different from the source frame the energy/frequency/wavelength will be different from that observed in the source frame. The speed will NOT be different. > All similar photons have the same properties in their respective source > frames. Why would anyone want to make claims about its properties in any > arbitrary frame. It would be totally useless. Not useless, it explains observed red and blue shifts. >>> What properties are possessed by photons then? >> >>Spin, angular momentum, frequency, energy, polarity, and velocity. >> >>Speed is always c. > > wrt its source. Wrt its source. Wrt any target. >>Rest mass is always zero. > > maybe..but debatable. > What constitutes mass. E = m c^2 / sqrt(1 - v^2/c^2) so m = (c^2 / sqrt(1 - v^2/c^2))/E -- 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: G on 3 May 2005 04:54
Henri Not to defend SR-Ians too much but I think this is how the theory goes: I have been analysing it and will hopefully add to my diagram soon. "Simple analysis will show that the light pulse is catching up to the spaceship at c-v. " About this and the light pulse towards Andromeda: Not to defend SR-Ians too much but I think this is how the theory goes: In the reference frame of the asteroid, the rod, the clock (all are in one inertial reference fame, not moving wrt each other) the speed of the sapcship is measured as v, and the speed of light is measured as c, that is, take the time it takes for the light to travel from the asteroid to the point on the pole with the clock and it will show the speed of light as c. The problem is with observers moving in Andromeda and also those on the spaceship. They will measure the light speed as c, that is they also place their rods with a clock on the end, and measure the time it takes from the time the light passes the clock to the time it reaches the bottom of the pole. In their reference frame, and the since c is a constant, what will they find? That the speed of light is exactly c. At least that is how the theory goes. Group am I correct? If the Andromedans had a long enough rod to reach the source, they will find that the time for the journey makes for a value of c. What about the person on the source ? Will they measure the same light speed WRT to the rod? Yes because for them, the rod has contracted and so the speed works out to c in that case as well at least I think that is the theory. This is why we need experiments: cephid variables should settle it : hope to have a look In fact, maybe we should make a list of already done experiments and published results and if they support or contradict SRT. Good luck with the rotating thing. A diagram would be nice. G |