Existence

You DO realize NoNukes has been bending over backwards for ~600 posts explaining this very thing to you......

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"Why don't you call upon your God to strike me? Oh, I forgot it's because he's fake like Thor, so bite me" -Greydon Square

But you can measure the time between emission and detection. This allows you to measure the time it takes for the photon to travel the measured distance.Since the speed of light is constant and the distance is longer for the moving reference frame this means that time has to change as well to keep the speed of light the same. This is exactly what happens. Time in the moving frame of reference (your starship bicycle) moves slower compared to your wife's frame of reference so that the speed of light is the same for all frames of reference.Edited by Taq, : No reason given.

Hi Taq, How?The clock does not function. You just don't get it do you.According to SR postulate #2 the light can not go at an angle. It has to go 90 to the direction of travel from the point emitted. The pulse can not add the speed of the cycle to its speed, if it does postulate #2 is invalidated.Take your choice is postulate #2 invalidated by the light going at an angle? Or does the light go at a 90 angle as required by SR?God Bless,

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"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

Hi ICANT, Distance has nothing to do with the observations. View one is what anyone will measure/detect/observe/deduce if they are at rest with respect to the light clock regardless of their distance from the apparatus. Further, it is not necessary that they be able to see the beam from their vantage point. The light clock is provided with a detector that provides an indication that the beam has struck the upper mirror some number of times.On the other hand, the saw tooth is what is observed/measured/detected/deduced by an observer who is not at rest with respect to light source, even if he is momentarily close by. Again, the word "observe" here can include indirect indications that the light beam has struck the mirror. The detection circuit continues to indicate that the upper mirror is being struck by the beam despite the fact that observer knows that the mirrors are moving in his reference frame. Easily done.Once the laser beam exits the space ship, it will continue on through space. An observer's eye could intersect the beam at any point in space along the beam's path. Alternatively, the observer might witness the fact that the beam has struck something laser sensitive.One thing that you continue to have problems understanding is that a frame of reference is not confined to a single location in space. Observations can be made from any point in space as long as the observer is at rest with respect to the origin of the coordinate system of the inertial frame. Yes there are vantage points from which nothing can be seen. But why deliberately pick such a point?For example, we can imagine observers at rest with respect to the earth and positioned at 1.1547 light second intervals along the space cycle's path. The light clock pulse would hit the upper mirror as it passed each one of those observers, each of whom is equivalent to the wife. Regardless of whether the observers could actually see the beam, the observer could detect a radio signal transmitted by the circuitry attached to the top mirror. Once those observers have conferred among themselves, they will have no problem drawing the path of the light beam using the wife's coordinate system. I think even you can picture what that path would look like.That's also why your entire diatribe about not being able to see the light beam is completely beside the point. If you cannot see the beam, as long as someone who is at rest with respect to your position can directly or indirectly detect the beam, then that observer can make the observation for you.You describe things as if they have no consequence because you cannot see them. That's simply wrong.

Why doesn't it function?Excitation is marked by the injection of energy into the system. Detection is marked by an increas in energy at the detector. This is basic physics. According to SR, it has to. That angle is measured after the fact. It has to be that way. Exactly. You have just proved our point.

Yikes. ICANT, you should be careful about tossing around accusations that others don't get it. It will only makes you look foolish if you ever manage to grasp what others already understand. You are neglecting the fact that for an observer moving with respect to the light beam, the coordinate system of the observer is also moving. A point that is fixed in the clock's reference frame is not fixed in the "moving" observers frame of reference. If the light beam moves at 90 degrees, that means that the beam's X coordinate has a fixed value in the clock frame, while the beam's Y coordinate is constantly changing to approach one mirror or the other.However, in a second frame of reference that is moving relative to the clock along the X axis, the X coordinates of events are not fixed but are increasing (or decreasing depending on the direction of motion) constantly with time. Accordingly, from that second frame of reference, the beam cannot be moving at a 90 degree angle in the moving observers coordinate system. Postulate #2 merely requires that the speed of light in a vacuum, regardless of its direction, is always c as measured any inertial frame.Neither SR nor postulate #2 require the 90 degree angle, and yet, as has been shown, SR is completely dependent on postulate #2 being valid. Clearly there are more options than you are allowing here. Nobody is going to defend your ridiculous parody of the theory.Let me describe your folly in another way. Not only do you not accept SR, something which does not make you unique, but you cannot even reproduce the predictions of SR correctly, which makes your opinion about it decidely uninformed.There are countless resources available that describe the operation of the light clock, and how the light clock would operate from the frame of reference of different observers. If you are truly interested, I'd be happy to point you to a good reference.

Hi NoNukes, But distance has everything to do with the observations.The light beam has to travel to the eye of the observer before it can be processed. Thus the distance the observer is from the source determines the duration it takes for the light data to reach the eye. That is the reason different observers will see different things.Let me repeat my fig 1 here.

fig 1                         fig 2
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 Local observer     Observer at a distance 

If the light was enclosed the pulse would bounce off the top mirror and return to the bottom mirror as in the first fig as seen by the local observer.To a non local observer the pulse would appear to them as in fig 2 due to the fact that each nanosecond the pulse is being forced in the direction of the travel of the cycle. Thus each step of the light to the top mirror is thousands of miles from the first and this information takes longer to reach the eye. The eye then assembles the light and low and behold it looks like the light is traveling at an angle. But in reality the pulse went at a 90 angle to the motion of the cycle.

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2. Second postulate (invariance of c)

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As measured in any inertial frame of reference, light is always propagated in empty space with a definite velocity c that is independent of the state of motion of the emitting body.

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SourceThe pulse will go in a straight line from the point emitted independent of what the emitting body does.My train experiment which you ignored.I propose the following thought experiment.Build a frame that contains a mirror at the top and bottom facing each other. The mirrors are to be 18" long with 1 meter distance between them. The unit is not closed, but open.Mount a laser pen in the center of the bottom mirror flush with the mirror surface, that has a sensor on the bottom to receive a signal to cause the laser to emit a pulse of light.Mount the frame on a flatcar of a minature train with the sensor on the pen exposed under the flatcar.Build a track as long as you need to conduct the experiment placing sensors 1 meter apart to turn the laser on when it passes over it.Move the train forward until the sensor causes the laser to emit a pulse of light, and the light will hit the top mirror.Lets extend the track to the planet I am on my journey too or any other planet. Then lets speed the train up to 74,948,114.5 meters per second (0.25 c). The laser light travels at 299,792,458 meters per second.Each sensor the laser sensor passes over sends a pulse of light towards the mirror in the top of the frame.The laser pulse of light is traveling at a 90 angle to the direction of the train so the pulse of light will go straight up from the source's position at the time emitted at 299,792,458 meters per second.According to postulate #2 the pulse of light can not acquire the forward motion of the source of the light.That means if the train sitting on the track ready to accelerate on it's journey the pulse will not be doing anything, as it has not been emitted yet.When the train begins to move slowly each time the laser pen sensor goes over the sensor on the track a pulse will be released and will bounce off the top mirror.As the train increases in speed the pulse will strike the mirror further and further from the center of the top mirror opposite the direction of the train due to the fact that the pulse can not take on the forward motion of the train.When the train reaches 74,948,114.5 meters per second the light pulse will hit the back edge of the top mirror. Increase the speed of the train by a few meters per second and the pulse will miss the top mirror.If it does hit the top mirror then the pulse has taken on the forward motion of the train and postulate #2 is invalidated.If it doesn't hit the top mirror then all this stuff you been spewing about what an observer will see is invalidated.Which is it?I asked 2 question in Message 658 that you did not answer so I ask them again.Do you believe the pulse of light can add the forward motion of the train as the basketball does of the player bouncing the ball?Do you believe the light beam from my laser through the tube can be seen from 10' away mounted on a frame 1' off the floor and reflecting off the ceiling?God Bless,

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"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

Hi NoNukes, You mean like if Modulous pulled his space bike out of moth balls and joined me in my journey and he is riding along side of me and looks over at the clock you mounted on my handlebars that I changed to coincide with the travel of my cycle he would see the same thing I do. Yes I get that.But if he is sitting still relative to the earth and the planet I am headed too, half way between them and I go by him at 0.5 c He is not going to see anything. In a vaccum he would not even know I went by. It would be like me trying to see a laser beam from the tube out of a roll of paper towels shining towards the ceiling.
So get real. Then why does it have part 2 which says "that is independent of the state of motion of the emitting body"?Part 2 says it can't take on the forward motion of the source of the light.That means if they are going in the same direction or opposite direction or at a 90 angle to the motion of the travel of the cycle.So the pulse of light has to go straight up at a 90 angle from the point emitted without moving any distance in the direction the cycle is traveling.That being the case the pulse of light emitted from its source in the middle of a 18" mirror can not strike a mirror 1 meter above it in the clock mounted on my handlebars if the clock is open.If the clock is closed the pulse will hit the back edge of the top mirror and return to the back edge of the bottom mirror. The next pulse released will do the same.If it does not hit the back edge of the top mirror then it has taken on the forward motion of the cycle which invalidates postulate #2. You are right in that postulate #2 does not require the 90 angle.The clock is mounted on the handlebars of the cycle and the pulse of light is going up and down in relation to the forward motion of the cycle.That is what requires the 90 angle.The postulate does require that the pulse be traveling at 299,792,458 meters per second in a straight line from it's point of origin.The postulate does require that the pulse of light not move one iota of distance in the direction of the motion of the cycle.If the pulse of light moves a smigen in the direction the cycle is traveling postulate #2 is invalidated. And if postulate #2 is valid the pulse of light emitted from the center of an 18" long mirror spaced 1 meter from the top mirror can not hit the top 18" long mirror in an open clock on the handlebars of my cycle traveling at 149,896,229 meters per second. I don't know if I can accept SR or not.I can not accept SR as has been presented here in this thread.I can accept that the speed of light is c.I can accept that a pulse of light can not take on the motion of the source of that pulse of light.I can not accept that the pulse of light emitted from the bottom mirror in the above example can strike the top mirror in the middle, and accept postulate #2 as valid. The pulse of light would have to take on the motion speed of the cycle to do so, which invalidates postulate #2.I know for a fact that I can not see a laser beam that is projected from a tube towards my ceiling. I can see the results of the beam hitting the ceiling and if I look into the tube I can see the source of the beam. But I can see a beam of light between the end of the tube and the ceiling. That is a fact jack. If you don't believe it try it yourself. But I am not trying to reproduce the predictions of SR as told to me by someone.I am trying to examine an experiment that should confirm or invalidate the predictions of SR.Why don't you take my train experiment and show me how the pulse of light can strike the top mirror if SR is correct that the pulse of light can not take on the motion of the source.As far as that goes why not take the cycle one discussed above and show me how the pulse of light can strike the top mirror if SR is correct that the pulse of light can not take on the motion of the source. Yes there are dozens of people who have wrote articles describing how the light clock would operate.There are also dozens of people who have wrote articles describing how the light clock does not operate as explained by those folks.Trying to convince me that what someone has said is true is like me trying to convince most folks here that God exists because men over thousands of years wrote down experiences with God and those different books have been gathered into a book called the Bible, and I know it is so because it is written down in several books by many different writers over thousands of years.Now if you want to take the examples mentioned above and show me how the pulse of light can hit the 18" long top mirror from the center of an 18" long bottom mirror placed 1 meter apart formed into an open clock with the source of the pulse of light in the center of the bottom mirror you might make some progress.Because if the pulse of light can not take on the forward motion of the source of the pulse of light as stated by postulate #2 there is no way the pulse of light can hit the top mirror with the cycle to which the clock is attached moving at 149,896,229 meters per second.Let me expound upon the problem I have with SR.Lets modify my train experiment.First we put the tracks in a tunnel as long as you desire.Then we will trade places of the source of the pulse of light and turn it into a steady stream of light. We will move the trip sensor from the track and place it in the middle of the bottom mirror. We will then replace all the sensors on the track with laser pens that will send a beam of light towards the top mirror of the clock.So now we have laser pens placed 1 meter apart on the track that will turn on when the trip sensor passes over it. We need to realize that the pens have to be aimed at an angel for the light to hit the top mirror but that will not effect the purpose of this experiment.The laser pens being attached to the tracks will produce what SR says the light beam does in reference to its source.All the pens are calibrated to put a spot on the ceiling of the tunnel exactly 1 meter apart.Everything in place we start the train very slowly the trip sensor passes over the first laser pen and the light reflects off of the mirror, but as the speed increases the light beams begins to miss the mirror all together when the train reaches 74,948,114.5 meters per second none of the laser pulses will hit the top mirror they will all miss going behind the mirror.You should be able to measure the distance between the laser dots on the ceiling and them match the 1 meter distance the pens are apart that is producing the light beams.You should be able to look down the track and see a lot of little laser lights where mounted on the track and you should be able to see a lot of little laser light reflections off the ceiling of the tunnel. But if you look straight down the tracks you will not see a bunch of laser light beams from the source to the ceiling.This proves several things.1. You can see the source light from a short distance on the track and the reflection of that light on the ceiling of the tunnel.2. But you are limited as to the distance you can see the source light and the reflection on the ceiling of the tunnel.3. It proves that you can not see the light going up and down in a light clock at a distance.My searchlight example shows that our little attemps to create a small light that can be seen at great distance is a failure.Now if you disagree please show where you disagree and what is wrong with what I have presented.God Bless,

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"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

Hi Taq, Because the clock as designed is attached to my handlebars on my cycle with the light beam going up and down at a 90 angel to the travel of the cycle. While sitting on earth it works perfectly, going up and down in the center of the mirror.But when I reach 149,896,229 meters per second the light beam is missing the top mirror by 4 inches as it goes behind the mirror. The angle I was talking about was the angle to the source of the light beam that would be required to produce the sawtooth pattern.The light beam must go in a straight line from the source of the light beam regardless of the motion of the source.That means the light beam would go at a 90 angel to the direction the cycle is traveling with the clock attached to the handlebars.At 149,896,229 meters per second the light beam will miss the top mirror by 4 inches. The 90 angle is determined by the light source being pointed up at a 90 angle to the travel of the cycle. Are you then agreeing that the light beam has to travel in a straight line from the point emitted from the light source in the direction the light source is pointed?If you are all the stuff you been trying to cram down my throat is a bunch of bull chips or cow patties whichever you choose.Cause if that light beam has to go in a straight line from the point emitted it will miss the top mirror and there will never be any light beam bouncing around making a sawtooth pattern as presented in the light clocks presented in this thread.Thank you.God Bless,

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"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

The light pulse always hits the top mirror because we're talking about a clock that operates by "ticking" every time a light pulse reflects between the two mirrors. And since we're talking about time dilation as a result of velocity and not as a result of acceleration, there's no outcome where the light pulse "misses" the top mirror because we've aimed the pulse to be right where it's supposed to be one second from now to be reflected by the mirror. And we only have to do this once at the beginning; even on your moving space cycle, because your speed is constant the light pulse continues in a directly vertical up-and-down path.The case for acceleration is different but, as you can see, we've established that time dilation occurs between any two reference frames that are not at the same velocity; relatively-accelerating reference frames are nothing more than a special case of this where the exact relative velocity is not constant but depends on time. Because it is non-constant it must therefore be non-zero; ergo, we've proven that time dilation occurs under acceleration as well as under constant velocity. The Michaelson and Morley experiment is what I was referring to as "irrefutable experimentation that they see the photons covering that longer distance at the same speed that light has in any vacuum anywhere in the universe - c." Long before Einstein, it was a settled matter of experimental fact that the speed of light in a vacuum is the same for all observers regardless of their velocity or acceleration. They run faster in orbit than clocks on the ground because clocks on the ground are slowed by the acceleration of 1 G that they experience. (You know, G's? Like when people on roller coasters or in fighter jets talk about "G-forces"?) Clocks in orbit, by virtue of following an accelerating curved path, run slower than clocks that are motionless relative to clocks in orbit. Or, to place these three locations of clocks into an ascending order of relative time dilation:Clocks in space but motionless relative to the Earth
Clocks in space orbiting the Earth
Clocks on the surface of the EarthWe adjust clocks in space orbiting the Earth to match the slower rate of time on the surface of the Earth because that's where we live, and therefore where we'd like to tell time. (And there's a crapload of clocks down here already and it would be a pain in the ass to speed them all up, compared with adjusting the 31 clocks on the GPS satellite fleet.)And again time dilation of clocks on Earth compared to clocks in orbit of the Earth occurs because the speed of light in a vacuum is the same for all observers. Oh, is this where you're getting confused? We're assuming your wife is stationary near the Earth, not actually at its surface experiencing its gravity.If your wife is actually on the surface of the Earth she'll be experiencing her own time dilation due to being in an accelerating reference frame. Which of you will experience slower time than the other is just a function of which of you is experiencing the greatest amount of time dilation. (If your velocity is as high as one-half the speed of light it will certainly be you. But GPS satellites in orbit don't travel anywhere near that fast.)

No, the light clock will reflect up and down regardless of your speed if your speed is constant. That's simple physics. The light beam goes in a straight line up and down relative to the cycle, because the light clock is attached to the cycle. To people standing alongside the space road as you drive by, the light beam traces a characteristic double sawtooth because the cycle, and therefore the clock, are moving relative to them. The light beam never overshoots the mirrors because the entire light clock is moving - the mirrors and the beam.This isn't that hard to understand, and it proves that time dilation occurs at any non-zero velocity. In the case of acceleration it must also occur, because acceleration means "a change in velocity over time", change means that the velocity is non-constant, and zero is a constant, therefore the velocity cannot be zero when a body is accelerating. Thus time dilation occurs in both constant velocity and accelerating situations. Bodies on the surface of the Earth are being accelerated at 1G. Ergo, bodies (like clocks) on the surface of the Earth experience time dilation relative to bodies not subject to its gravitation.It's all quite simple. It's disorienting to find out that time isn't a constant, but it's the natural result of something that has been known to be true since 1886: the speed of light in a vacuum is the same for all observers.

Hi ICANT, This expression of denial is simply ridiculous. After this message, I'm not going to make any serious attempts to address arguments of this nature except to ridicule them. If the action is too fast to witness with the naked eye, we can simply use instrumentation to detect things. If one observer is out of position, then we can use a second observer who is also at rest in the frame in question.Since you've acknowledged that a light clock on earth would operate such that the light will be reflected between the mirrors, I have two questions to ask.First, why do you consider the earth frame to be special?You've indicated in a previous post that the earth is moving at tens of thousands of miles per hour through space. Why doesn't this motion of the earth prevent the light beam from returning to the top mirror? After all, within a few seconds on earth, the top mirror will be many miles distant from its original position.Second Question.When we look at the motion of the light beam on earth from a second moving coordinate system also located on earth, it is evident that from that second frame of reference, the light clock is moving.Even if an observer is moving at a mere 3 mph relative to the light clock, after one second, the top mirror will have moved 4.4 feet away from its starting position in the observer's reference frame. Yet we know that an observer's simply moving by and looking cannot possibly cause the light to miss the mirror.So what gives? Surely we don't have to pretend that the observer can no longer see the light clock after having moved 4.4 feet.It is the essence of relativity that we should expect that the results of our experiment would be the same regardless of whether the light clock is moving inertially and the observers are considered "stationary" or the observers are moving inertially and the light clock is considered "stationary". If this were not true, then it would be possible for an observer to determine his absolute velocity by conducting experiments within his inertial frame. The truth is that relativity requires that every light clock, pool table, scattering experiment, etc. behave the same to all observers at rest with request to the respective apparatus so that absolute velocity determinations are impossible. Part 2 is correct. Postulate #2 requires the speed of light to be constant for all observers in any inertial frame. A photon will travel 186,282 miles per second in a vacuum, even if the source of the photon is moving. If the beam is observed to travel at a different angle, that does not mean that the speed of light has changed. That issue is simply not addressed by postulate #2. I don't expect my pointers to prove to you that SR is correct. But what is evident to me is that you still haven't wrapped your head around what an inertial frame of reference is and that as a result you cannot understand what SR does and does not predict. My hope is that someone else might be better able to explain it. My own efforts to explain high school physics to you have been dismal failures.But with regard to those dozens of articles that you believe support your interpretation, you are wrong about what those articles contain, ICANT.I doubt that you can find any serious articles (by an engineer or scientist) wherein the author rejects the light clock thought experiment without also rejecting the constancy of the speed of light in a vacuum. For example, Hatch takes the position that the speed of light in a vacuum is not constant. Another person you cited, whose name escapes me takes the position that the speed of light is affected by the velocity of the source. These authors take these positions in order to refute special relativity.In any event, it is possible to derive the Lorentz-Fitzgerald transform equations directly from the fact that the speed of light is the same as viewed from two different inertial frames, without introducing a light clock. Einstein does exactly that in his 1905 paper. Isn't what you can see enough to determine the path of the beam? If can determine the coordinates of two points of the light beam isn't that enough to determine the complete path in your own coordinate system? I did ignore the train experiment because the setup was a bit confusing and even the problem statement has some bad assumption. Let me deal with one fundamental problem. Traveling exactly vertically (90 degree ange), yes, but in which frame of reference? Let's consider the frame of reference in which the train is stationary. Let's define the time a laser beam reaches the level of the bottom of the frame at time zero, and take the height of the frame to be 1 meter.If the X (horizontal) coordinate of the beam at the time the beam reaches the bottom frame is zero, then what is the X coordinate of the beam in the trains reference frame at the time the beam reaches the top of the frame?Well, the light beam would take approximately 1/299,792,458 seconds or about 3.33 nanoseconds to travel 1 meters. In 3.33nsec, the origin of the train's coordinate system in the train's at rest frame would be 0.25*299792458 * 3.333 nsec = 0.25 meters to the right of its original position in the tunnel frame of reference. Thus for every 1 meter of travel of the light beam, the lead edge of the light beam is 0.25 meters to further to the left in the train coordinate system.Hmm, the beam does not appear to be traveling vertically in the train frame of reference. It is not going to be all that surprising that at a high enough relative speed the light beam is going to miss that top mirror.A little trigonometry shows that by the time the light beam reaches the top of the frame such that Y = 1 meter, the X coordinate is 0.2582 meters to the left of the point at which the light beam reached the bottom of the frame. The angle from vertical is about 14.5 degrees as measured in the train frame of reference. Note also that while the train moves right, the light beam moves to the left in the train's frame of reference. Surely that is not a result of the light beam "taking on motion of the train".Then what has transpired here? Did the motion of the train have some effect on the direction of the light beam? Absolutely not. The motion of the train affects the coordinate systems (time and distance) used to describe and experience events on the train, but it does not change the light beam. Using coordinates in which the tunnel is at rest, coordinates, the beam travels exactly vertically while the mirrors move and the light beam misses the mirror.So I'm not sure what your point is here. The experiment is not at all analogous to the light clock experiment in which the light beam is directed vertically in the frame at which the mirrors are at rest.As I see it, among your problems with SR is that the theory is over your head. If you cannot appreciate how coordinate systems in different inertial reference systems work so that you can convert from one reference frame's coordinates to another, and you cannot do so, then you are going to continue to make bad predictions using SR. And falsifying a bad prediction does not refute SR. It simply makes you look foolish.

Hi crash, Not if postulate #2 is valid. According to postulate #2 the light beam has to go at a 90 angle to the direction of travel as the clock was mounted on the handlebars with the light source mounted flush with the center of the bottom mirror at a 90 angle to the travel of the cycle.For the light beam to hit the top mirror in the center the light beam has to acquire the forward velocity of the cycle as the clock is mounted to the cycle.If that happens postulate #2 is invalid, as the light beam travels in a straight line from the point emitted from the source regardless of the velocity of the source.God Bless,

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"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

Hi NoNukes, But I had only mentioned Modulous on his space cycle and as I remember we installed no detection devices on them. It is the one created for us to live in. So yes the clock on the train is moving and the clock on the space cycle is moving. What is the point? After an hour the top mirror will have moved not one inch from its original location other than that caused by the location and earth and its movement.Now if I am shopping for a light clock and I am walking down the street at 3 miles and hour approaching a store with a light clock on a shelf in the display window and I stop and look at the light clock we both are at rest. Then I turn my back to the light clock and walk 4.4 feet but you tell me no the light has moved 4.4 feet. If you ask the third graders across the street they will tell you I was moving but the light clock was sitting in the window. Well back to my example above. I am looking at the light clock in the display window and then turn my back to the light clock and begin to walk down the sidewalk I can no longer see the light clock. It makes no difference how fast or slow I walk I can't see the light clock. Now if I turn and face the light clock I can then see the light clock. You could ask the third graders across the street and I think they would confirm I could not see the light clock while walking away from the light clock. You can consider anything you want and claim anything you want.If I am on my space cycle traveling towards a planet with the distance being reduced at 0.5 c and the distance between me and the earth increasing at 0.5 c and the light clock is sitting on my handlebars you can't make that light clock not be moving at 0.5 c to save your life. It don't make any difference how much you claim it is stationary the light clock is moving towards the planet at 0.5 c. Where does it make that statement?

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2. Second postulate (invariance of c)

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As measured in any inertial frame of reference, light is always propagated in empty space with a definite velocity c that is independent of the state of motion of the emitting body.

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SourceThat statement says that as measured in any stationary frame (you know the one Einstein said was not moving) that light always has a velocity at c that is independent of the state of motion of the emitting body.It does not say anything about being independent of what that frame is doing.It does say independent of the motion of the emitting body.You know like the light source mounted flush in the center of the mirror in the open light clock mounted on my space cycle.When that pulse is released it goes in a straight line at a velocity of c whether the source is in a non moving frame or in a moving frame which neither one can affect the direction of the light beam or pulse. This is what you have been telling me up until a little later in this post I am answering.For the light emitted from the source mounted in the middle of the mirror in the light clock on my cycle can not strike in the middle of the mirror on top of the open clock, or even hit the mirror according to postulate #2. I can make that assumption but I can not see the beam of light and it is a steady stream. That was my point. If I couldn't see the ceiling or look down in the tube to see the source I would not know it was there.So if you were trying to observe the light clock on my cycle and you were riding along side of me at a distance of 100' you could see neither the top mirror or the source of the light.Now if I had something hooked up that could send Modulous a radio signal every time the beam made enough trips up and down for
the cycle to travel 299,792,458 meters it would never send a signal.The first beam missed the top mirror. So if the light beam goes 90 vertical from its source in relation to the travel of the train the light beam will miss the upper mirror, if postulate #2 is valid. The light beam does not move to the left. We will imagine we can see the beam. And in doing so the light beam would appear to us as moving to the left when it actually went at a 90 angle in relation to the travel of the train from the point it was emitted.This optical illusion is not caused by the light beam taking on the motion of the train. It is caused by postulate #2 being validated. The point is for postulate #2 to be valid the light beam has to miss the mirror on top as the math shows.
If the light beam hits the mirror on top then postulate #2 is invalidated, as the light beam has to take on the forward velocity of the train.Which is it? What prediction did I make?I did state postulate #2.

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2. Second postulate (invariance of c)
As measured in any inertial frame of reference, light is always propagated in empty space with a definite velocity c that is independent of the state of motion of the emitting body.

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SourcePostulate #2 says the light is always propagated in empty space at velocity c. I have agreed to this statement.Postulate #2 says that velocity is not effected by the motion of the emitting source.As I understand this second part it means that the light beam pulse will travel in a straight line in the direction pointed from the location emitted regardless of what the motion of the source is.Now if I am missing something on this last part of postulate #2 please explain what I am misunderstanding.God Bless,

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"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

Absolutely wrong. You're getting too hung up on the actual mechanics of the light clock, which is absurd because there's no such thing as a light clock. You can't have a perfectly reflective mirror, so your single photon eventually is either scattered by the mirror or absorbed by it. You can't have two mirrors in perfect alignment, so the photon is either absorbed by one of the mirrors or it escapes from the mechanism.It's a thought experiment, ICANT; just as you've asserted an impossible motorcycle that can propel you at impossible accelerations (that, normally, would turn a human pilot into chunky salsa) in the vacuum of space, just as you've asserted an impossible wife with eyes so good she can see you and your motorcycle at a distance of multiple light years, we're asserting an impossible clock that is so large - hundreds of thousands of miles long - that a single photon bouncing back and forth between two perfectly aligned, perfectly reflected mirrors bounces off a mirror once every second.There's no conceivable technology that would allow a mirror to "tick" in response to the reflection of a photon, but the part you're hung up about is even stupider.Just assume that the clock is mounted on a vehicle traveling at .5 c, and that it works as described - reflection of a pulse of light, directly up and down, between two mirrors. There's no reason to wonder about "reflection angles" and the like, because the mirrors are moving at .5 along with the vehicle, and therefore they're always just where they need to be to reflect the light pulse. By definition. It doesn't need to acquire it; it already has it, because we're defined the clock into existence on an already-moving space cycle. As long as velocity is constant, the light clock will function. And the light clock demonstrates that time dilation occurs in a constant non-zero velocity system. By calculus, we can prove from that that it happens in an accelerating system as well.Again it's a mistake to get too hung up on the practicals, here. It's a thought experiment, not a real experiment - light clocks, space cycles, and multi-light-year vision are all impossibilities. The real experiment, if you want to learn about it, is what I've already told you about - the Michaelson-Morley experiment that, in 1886, proved beyond doubt that the speed of light is the same for all observers in every reference frame. It didn't take light clocks or space cycles or anything of the sort.Edited by crashfrog, : No reason given.