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Measuring The Relative Velocity Of Light 
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#217
Jun2604, 07:33 PM

P: 301

i KNOW that.
why do you think i said 48 chambers? because each ONE would be transmitting one BIT of information (either ON or OFF) to the destination.
each BIT of information can be transmitted to the other end of the tube 300 times faster than light speed. it is instantly processed by my computer and displayed on the screen (assume so to make a point). if you displayed the words "HI MOM" on your screen AND sent the data down the tubes AT THE SAME TIME (colocal simultaneity DOES exist) then i would receive those 48 bits of data FASTER than looking over and waiting for the light from your screen to register "HI MOM" to my eyes. we're talking 62 billionths of a second though for a 50 ft pipe of caesium, so the real result is "big deal?" but what this DOES say is using light for simultaneity DOES fail for transmission of information at superluminal speeds. in essense, if light is your limiter for this situation then the message DOES come out on the receiving end BEFORE it was sent in, calculated with light simultaneity 


#218
Jun2604, 07:37 PM

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Right here: That's exactly the problem! You can't just assume that this can be done. Again, I ask: Why are you being so stubborn about this? Why don't you believe the people who were there, when they tell you that this sort of pulse cannot be used to do what you say it can? What makes you think you know better than them, without ever having done any work in this field? 


#219
Jun2604, 08:46 PM

P: 301

the crux of the argument is information being transmitted at speeds faster than can be accomplished by light.
i was never arguing you that it's not feasible to do so because we lack the computing power to process that information at those speeds. not once :D 


#220
Jun2604, 08:50 PM

P: 301

they know it too since they work in the business. i'm pretty sure "it can't be done" is either fog to keep competition away from what they're going to pioneer as new technology OR their data is faulty and they have no idea what they're talking about (their experiment is a sham). take whichever of those two conclusions makes you feel the safest... :D 


#221
Jun2604, 10:40 PM

P: 565

Now we have the observers moving towad each other, but each is ignorant of he oher's presence. The grouind observer will will see a contraction to both rods to .9m each. Your statement that each observer would think the other's rod has changed and no agreement could be made, I Iassume you are placing each in the position of an effective stationary observer wrt the other. With a stationary observer noting changes, she still sees the rods shoren to .9c. But let us have the rods placed parallel and close to each other when they pass (or from an SR perspective when A passess B or B passes A) by each other. It would be physically impossible for each of the moving obsevers to claim hat their rod was longer than the other. First their relaitive speed with respect to the stationary observer is the same, and hence the stationary observer keeps the books straight from his perspective. However when passing next to each other there could be no disagreement between the observers as any disputes could be resolved with a simple inspection. So my question is what is the value, the wort, the utility of using assumed stationary frames when measuring relative velocity? The mathematics may allow you to do that and SR may allow you to do that, but there is the physical impossibility that the assumptions could ever be realized in practice, and then what of the assumed frame changes, i.e. to the rods? The point is that making an assumption that an observer on a moving frame is stationary and the other moving, (and vice versus) just because the mathematics appears to alllow this kind of comparison is contradicted by physical law. Moving bodies do not enjoy the arbitrary luxury of starting and stopping at the will of an observer in that particlular frame, under any circumstances, yet this seems to be a common practice among SR theorist describing reality.. Just to overkill a tad. If one rod is shortened to .9m and the other to .5m as measured by a third observer then each could claim, re SR, that the other rod had shortened to .4m? How long would this assumption be demonstrably true, if ever? Especially when they pass next to each other and see the differences? Which they would see if their eyes were a few wave lengths from herods as they slid past, agreed? If SR maintains this posture then it would have to conclude, as you said in your post, that each sees the other as shortening, but can the rod that is .9m wrt the stationary observer appear as .4m wrt to the other moving observer? Especially at the instant the rods were located next to each other, clearly visible to both? Couldn't each observer jump in the other's shoes and see the rods from the other's perspective? Apparently SR says you can. Each observer with the mere mental decision can place themselves in the other's position or themsleves at rest, or at any velocity compatible with the observed velocity as measured by the stationary observer? 


#222
Jun2704, 01:02 AM

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The problem at hand is not that we lack the technology to interpret the signal, the problem is that the signal that can break the lightspeed barrier is physically incapable of carrying information. Tell you what. You construct a superluminal communications system and send me a message at 300 times the speed of light. Go ahead and try it, if you're so sure. Send me a message at 300 times the speed of light, and I'll believe you. Waiting.... 


#223
Jun2704, 01:08 AM

P: 202

As I said numerous times, I'm no expert and I may have understood some things wrong, I'm just trying to help by my best. But why act like you are hearing what I claim the first time. Check out the usenet FAQ if you didn't already. http://math.ucr.edu/home/baez/physics/ barn and pole paradox is especially relevant to this 


#224
Jun2704, 01:46 AM

P: 565

[Tom  this is just an intejection for your consderation.
Frame to frame references’ When those describing some aspect of SR use the terms that “the moving frame1 can consider itself stationary and the moving frame2 as moving” I ask is this a legitimate dynamic in mathematical analysis?. From this we get assumptions that a moving train, for instance, can consider itself at rest and the platform as moving. Now we know that only trains actually move and the stationary platforms remain stationary. In fact it is a physical impossibility for the described assumption to ever be realized, despite the allowed freedom and even encouragement of mathematical models to exploit the frame referencing processes as described. What is the physical justification for manipulating models in this manner? Here is a general and generic problem; two moving observers with the same velocity are side by side with onemeter rods in each of their frames. A stationary observer sees the rods shortened to .9m each, which goes unrecognized by the moving observers. Now we have the observers moving toward each other with the same shortened rods as observed from a stationary observer. SR theory allows either frame to consider itself as stationary and, I assume, that the other’s rod is .8m. Each will perceive the other’s rods as shorter than their own. When the observes get next to each other and the rods are measurable, at least by comparison, it would seem ludicrous to allow both observers at this point to determine any of the rods as shorter than the other. Where is the cut off point? Where is the frame referencing assumption limited, if at all? It appears to me that even the simplest example of one frame assuming a v = o posture, giving all velocity to another frame, or the inverse, and the consequential time dilation and frame shortening is nothing but a mathematical contrivance to have the observers determine which is shorter or longer at their singular decision. I trust you can appreciate the seriousness of this item, which is one of many that minimize any enthusiasm from serious consideration of studying SR in depth. I believe you when you say SR will predict what ever you say. I will not be engaged in any discourse on what is or is not SR theory and what are its affects. I assume the truth of the matter and if I see an objection I will scrutinize that which I observe. You have seen my posts, I have seen yours, and it is about time we recognize that we aren’t going to change anyone’s mind easily. In fact minds don’t get changed in matters like these without conscious decisions being made. Ram1024 made a good suggestion that we strive for some real experiments to conduct. If sufficient professional creativity is applied we can design the experiments in threads. I was considering the experiment you referenced where the speed of light c wrt to some gamma particles (if I recollect) moving at .99c was measured. . Assuming the validity of the experiment as run what could be adjusted to determine if any objections originating in the forum can be exploited such as Grounded’s added velocity scheme, or moving platforms radiating photons from A and B to M the midpoint etc. It is going to get very dry when the enthusiasm begins to wear thin and only the diehards are still going at it. 


#225
Jun2704, 02:19 AM

P: 565

That is my point in fact. If no one can tell, why assume the impossible to achieve something, just because the mathematics allows the operation? Wespe, would you ever make the physical assumption that a train station was moving and the train right there in fornt of the station was stationary, assuming you noticed a relative motion between the two? I say you would not. What then is the value or even validity of making such an assumption? You might do it to solve some aspect of a problem but you would never assume the physical reality of the assumption. 


#226
Jun2704, 04:04 AM

P: 202

Yes, you can photograph them. But, you must also take note of the times of the taken photographs. Suppose, just suppose, that your rod is 2 meters long and the passing rod is 1 meter long and there is no contraction. Naturally, the ends would not pass each other at the same time, and the photographs would be taken sequentially. By knowing the difference in these time values, you could calculate how long the other rod is. Now, make the other rod 2 meters again. Due to relative simultaneity, the ends cannot meet at the same time, and you would calculate a length smaller than 2 meters, just like the above example. And since relative simultaneity is mutual, so is length contraction. If you ask why can't they meet at the same time: because that would be a moment simultaneous in both frames, which is not ok with relative simultaneity. (Of course I know you don't accept relative simultaneity, but when all the effects are combined, SR seems consistent within itself.) [the above explanation may be a simplification and may be not 100% correct, that's just how I think it is explained] 


#227
Jun2704, 06:10 AM

P: 76

The MMX was testing the relative speed between a ray of light and the aether. This is the experiment they conducted with the interferometer: My point is, if there is no aether, the MMX was accurate. Agree? Why are we still trying to make up reason why it isn't accurate? We didn't measure a change in speed because there is no aether that resists the motion of light. Why did Lorentz and Einstein have to explain why we didn't measure the resistance? 


#228
Jun2704, 07:18 AM

P: 565

One definition I have here is: "Events simultaneous with reference to the stationary frame are not simultaneous with respect to the moving frame, and vice versa (relativity of simultaneity)." Not to beat a dead horse but this definition was taken from Einstein's train experiment where the fact that the moving platform was moving and that an observer once located at the midpoint of the A and B photon sources in the stationary frame has moved from that midpoint and thereby she surrenenders any chance of measuring the photons simultaneous arrival at the midpoint in the stationary frame, or simply she is no allowed to to determine the photons were emitted sijultaneously in any manner excepts measuring the simultaneous arrival of the photons at M in the stationary frame. There is no reference by Einstein or any other source I have been able to find that suggest the the measured speed of light is an element determining whether events are simultaneous. At this point then it matters not that we are using the photons as the medium determining simultaneity. It is from the mere measurement of the photons in sequence at B then A that contains the definition of simultaneity. What is somewhat disturbing is the statement where observers in the moving frame "must therefore come to the conclusion that the lightning flash at B took place earlier than the lightning flash at A." All other means of determining simultaneity have been discarded. If this was, and it is the current definition of simultaneity then the definition is flawed. The only question the moving observer needs to do in order to determine whether the events in the stationary frame were simnultaneous is to determine whether the photons were emitted simultanously, or not. The fact that the photons were observed sequentially in the moving frame does not limit to that process. The observers could make a number of a measurements and analyses that could verify whether the photons could be detected as being emitted simultaneously in the moving frame. In other words if the observers in the moving frame can determine the photons were emitted simultaneously in the mcving frame then simultaneiity of the events is satisfied. I claim I have done this in a number of posts and links. But let us proceed on and see what is the result of the finding the photons were not enmitted simultaneously. Here every reference body has its own particlular time, unless we are told the reference body to which the statement of time refers, there is no meaning in a statement of the time of an event. The absolute nature of time is scrapped from the adoption of the "most natural definition of simultaneity". i.e. the sequential detection of the B and A photons. The definition seems to be saying that knowing the photons were emuitted in the stationary frame does not rescue simultaneity as the observers have concluded the photons were not emitted simultaneously in the moving frame,by virtue of the sequential measurement iof the A and B photons. Therefore, I conclude that any determination that the photons were emitted simultaneously will restore the simultaneous characteristic of any particlular process. From this loss of simultaneity moving observers will determine their own destiny of motion independent of stationary observers or observers in other inertial frames. The mere fact that the moving observer at M, the midpoint of the photon sources, moved the instant the photons were emitted negated the survival of simultaneity, as it appears, the mere fact of detecting the photons sequentially set the chain of physical action that negagted absolute time, simultaneity and the propagation of light in vacuo become measurably constant in all inertial frames. If only the moving observer could determine the photons were emitted simultaneously, from her observation limited by the intrinsic parameters of her moving frame, there would be no special relativity. Special Relativity hangs by a thin and questionably fragile thread. I surmised I was close [I claim I've done it] to showing a way the moving observer could very easily determine whether the photons were emitted simultaneously or not from the panicked manner in which one of the posters to my thread began unleashing a barrage of ridicule, smirking, insults and purposfully confusing my posts and claiming conclusions and statemens in the post that were not made or inferred. He is a mentor so I suppose he is immune to any corrective process. The French have a word for it: Sabotage. 


#229
Jun2704, 02:11 PM

P: 202

Grounded, I feel like I'm just repeating what I had read somewhere. It would really make things faster if you did some reading on your own and discuss only what bothers you. Here are some good lectures: http://galileoandeinstein.physics.vi...cturelist.html 


#230
Jun2704, 02:44 PM

P: 202

[edit: oops I didn't answer your question. Yes, if you measure the shrinked length, and you were given the rest length, you can calculate the gamma and therefore relative speed and everything. But you can also measure relative speed directly. no time, have to go now..] 


#231
Jun2704, 07:27 PM

P: 301

apply some rational thinking on how the simple states of ON and OFF are combined together to create meaning. use some of that wondrous brain power you tote about on your neck every day to understand there's no need to get any other "information" from a single "pipe" EXCEPT 1 or 0. which is WHAT they DID get. 48 bits of data through 48 channels <pipes> reaching the other end 300 times faster than the speed of light. let's assume on the other end you see THIS:
each pipe transmitting merely ON or OFF each line translating to 1 letter the message reads "hi mom" it's simple, why are you confounded by it? 


#232
Jun2704, 07:36 PM

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On / off? I didn't know anybody still used that!



#233
Jun2804, 05:53 AM

P: 111




#234
Jun2804, 11:52 AM

P: 301

doesn't matter what "leaves"



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