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Time dilation question

10 Answers
If I have a push button connected to 2 wires. One wire attached to a crystal rotating once when electricity from the wire goes through it and then this rotation creates again electricity that goes through another wire that is attached to a light source that turns on as electricity reaches it. From the push button, the second wire that goes out is just attached to a second identical light source. The second wire is long enough so when the push button is pushed the electricity that goes through the wires and crystal gets at the same time as the electricity that goes through the other wire - So the light sources turn on together. NOW: if all this apparatus is put inside a moving vehicle that has a constant speed - according to experiments, the crystal that acts like a clock when rotating, will undergo time dilation but electricity going though wire only, will not (like light in vacuum), therefor if this apparatus was configured so light sources will turn on together when stationary, when moving, light sources will not turn on together. How could that be? And if it doesn't happen, why is it not an experiment that negates the existence of time dilation?
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Here is the same question, this time using light in vacuum instead of electricity in wires, by presenting a suggested experiment that reminds a known example that Einstein gave about special relativity, including a moving train, two mirrors inside the train and a light beam reflected between the mirrors (this suggested thought experiment, described here, only reminds the Einstein historically well known thought experiment of a moving light clock –please note critical differences):

1. Lets question how to measure and compare measurements for an amount of time that it takes a light beam to travel from a bottom Light Emitter-Detector (hereinafter LED) to a top LED in a train, once when the train is not moving (stationary at dock) and once when its moving at constant speed relative to dock (when measured only from within the train). As much as I understand this amount of time has got to be the same in both cases because the speed of light is constant at any direction and relative speed, while regarding the height of the train - there exists only horizontal length contraction, as seen from outside the train (in the same direction that the train is moving), so anyway there is no vertical length contraction from within the train. It seems that the time it takes light to travel from top to bottom LED or from bottom to top LED when looked at from inside the train is the same - doesn't matter if train is moving or not.

I think it's important to repeat that point: we are measuring from within the train, and not what is seen from outside the train. Measuring once when the train is not moving and once when the train is moving. The measurement is made by dividing the height of the train by the speed of light (constant at any speed or direction).

2. Suppose every time the light beam hits the top or the bottom LED in the train, there is a mechanism that changes the light color a little bit.

3. This light apparatus in the train will be a clock for us in here suggested experiment.

One more thing that should be emphasized here, is that every time the light beam hits the bottom or top LED, it registers a counter bottom and counter top photo-electric mechanisms with +1 hit.

4. If we assume as described in bullet 1, that time dilation dose not occur in the duration of the travel that the light beam makes from bottom LED to top LED of the train (in other words lets put aside in this experiment the concept of: 'looking at the light beam in the train from outside') - as measured only from within the train once when not moving and once when moving. As well we know time dilation must occur in the apparatus as a whole (assuming time dilation at constant speed was experimentally proved) - Then time dilation must occur somewhere in the parts and components of this clock apparatus that change light beam color, and other parts that emit light , and in the parts that register the number of light hits – but time dilation does not occur in that clock component, built with a vacuum tube, where light itself bounces - because the assumption here, is that light itself can not undergo time dilation.

5. If we add one more condition here, and it is that changing the color of the light beam, and emitting it back to the other LED, is a faster process than sending a signal over the wires of the apparatus towards the counter (say these wires are long enough), then:

6. When this experiment is made, results should be as following - as the train is not in motion relative to dock, and after running the clock for a while, the counter will show a certain number in accordance with a certain light color, and when the train is moving relative to the dock, the exact same number that will show on the clock counter must be (according to all above assumptions) coupled with a different light color.

This is because while the travel of light from the upper LED to the bottom LED takes the same amount of time (e.g. X seconds in both cases), in other parts of this clock apparatus, time dilation does make a difference (e.g. absorbing the light, changing color, emitting back, takes 2X when train is stationary, and 4X when train is moving, registering light hits takes 10X when train is stationary, and 20X when train is moving). The result is that if we stop the light hit counters of the moving train and the stationary train at the same counter numbers, the corresponding light colors will not be the same.

7. If such results will appear this might be a serious problem! That is because, although such results still show in a way the validity of time dilation, they enable experimentally to say if the train is moving or not, without looking out of the window - which brings physics back 105 years to the necessity of hypothesizing some sort of ether.

8. If none of the above will happen, and when counters will be stopped at the same number, corresponding light colors will be the same, then my question is, won't such results represent a situation, in which light itself undergoes time dilation?

Diagram: 10X/5X=2 but 10X/3X=3.33

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Okay. I've had time to take another look at your scenario. As I understand it, you're comparing two sets of cumulative measurements from your device: One from within a stationary train and another from within the train when it's moving.

As I noted earlier, I can't see your new diagram, so from your new description I'm going to conclude it's similar in design to the original, except that we now have two ways to measure instead of one The first is a cumulative color-changer that is triggered by a light beam (which, for ease of articulation I'll hereafter refer to as the "light counter") and the second is a numeric ticker that is triggered by current through a wire.

Please correct me if I'm wrong (it wouldn't be the first time!), but I believe your premise is that -- on the moving train -- since the light beam is unaffected by relativity and the current in the wire is, the ticker counter will register a lower total that than the light counter. By contrast, on the stationary train the two counts will be identical. So far, so good.

However, you recognize early in your scenario that the results from WITHIN the train will be identical. So what you're saying, in essence, is that the same set of results from the device's two counters DO MATCH when you watch them within the moving train, but DON'T MATCH when observed from another reference frame, or when compared to those of the stationary train. Of course, they either match or they don't, regardless of your vantage point, and regardless of relativity.

Don't forget that your train is moving through space. From within the moving train, the light beam is going to simply be travelling straight up and down between the LEDs. There are no relativistic affects WITHIN your reference frame, and the tickers will both count evenly.

But from the view OUTSIDE your reference frame, the light beam will be travelling at "angles" as the train, the device and the LED receptors all move through space between the flashes. In a way, the light beam IS being affected by relativity. It isn't slowing down, but it has farther to travel between each flash. So, while the ticker counter is slower, so is the light counter. Again, the tickers will both count evenly.

Whew! I think my brain is beginning to suffer from time dilation!

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Oops. I missed before that there were two separate apparatuses, one stationary and one moving. In your written explanation, you stated that "all this apparatus is put inside a moving vehicle," and I went by that instead of looking at the diagram. Looking at your diagram, I now also understand that by "wire" you mean a ball of wire in the second leg of the apparatus. I thought you meant the "wire" carrying the current to the lights. My bad. I think I now understand your scenario.

In any case, I still don't see how this could negate the existence of time dilation. Assuming both devices are equally affected by gravity, the inertial time dilation is going to affect only the device that is moving (and, unless it's moving VERY fast, only minimally). And it's not going to affect just the crystal, but everything within that inertial reference frame -- the lights, the wires, the crystal, everything.

Assuming both devices are absolutely identical, if there's a delay in the crystal half of the stationary device, there will be an identical delay in the moving device. The only difference is how it will appear to the observer, depending on his or her frame of reference.

If there's one observer in the first device's frame of reference (moving along with it) and another observer in the stationary device's frame of reference, they're both going to see the same exact delay in the lighting of the crystal half of their device. Again, it's a structural phenomenon, and has nothing to do with relativity.

However, if the observer at the stationary device's location observes the lighting of the moving device, he'll see the whole process proceed more slowly (including the delay in the crystal half). The time in the moving reference frame will dilate relative to that in the stationary reference frame.

I suspect what you're focusing on here is the notion that the crystal "clock" is somehow affected differently than the rest of the apparatus. But the clock -- whether it's moving or stationary -- is going to be affected no more or no less than everything else within its inertial reference frame. Assuming you can read it as such, it's only going to reflect the passage of time, not alter it.

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Woah! This question is becoming a full time job! It's a good thing I'm laid off for the week. Hehe. ;-)

As for your train experiment, I'll first say that there's a lot there, and I hope you'll forgive me if I've overlooked or missed something. Yet, from what I understand of your new scenario, you're only willing to consider effects and measurements within the frame of reference of a single train. In this case, relativity is irrelevant, because relativistic effects are only applicable when comparing one inertial reference frame to another.

No matter how sophisticated the device, if you're only taking measurements within the one train, they're going to be the same whether the train is stationary or moving. Within that reference frame, everything is going to appear normal, even if you're approaching the speed of light. The light beams within your device are always going to behave the same, because they and the train are in the same inertial reference frame.

This is a very crude analogy, but it's sort of like sitting on a passenger train waiting to leave the station, and the only thing you can see is other trains moving outside your window -- or perhaps you're the one moving, and the other trains are stationary! The only way you can tell there's any movement at all is that one train is moving relative to the other.

Within the train in your experiment, if there are no other reference frames - no other "trains" looking on - there will be no observable dilation of time -- but only WITHIN your train. Others will be able to see it, but if you're on the train, you won't.

Incidentally, I can't read your second diagram. The image must have shrunk and pixelated when it was uploaded.

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I was told that electricity going through wires, acts like light in vacuum - It has a constant speed, no matter what the relative speed is. So why can't one say that light in vacuum, or electricity in wires, are actually not affected by time dilation, and then, use this fact to build this experiment, in such a way that does not negate time dilation, but rather, shows that there is necessarily a mechanical reason to time dilation. This mechanical reason might be some sort of non-luminescent ether (Michaelson-Morley failed to find luminescent ether, but did not at all think of non-luminescent ether). So if a person sitting inside a moving vehicle will use this apparatus, he will be able to say if he is now moving at constant speed relative to the same stationary apparatus - without looking outside the window of this moving vehicle. I have been looking for an experiment that could be compared detail by detail to this experiment that I suggest, and which presumably was already executed in the past, and presumably already did show that the light sources will turn on together, no matter if you are with the stationary apparatus or with the moving one – But could not find such an experiment or such results in the past. I think I can explain why all the GPS and Muon experiments, and other known examples of time dilation, are different form this suggested experiment, and while these past experiments do affirm time-dilation effect, they are not built in such a way that they can affirm or negate a mechanical explanation to time dilation.

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No, they are not both accelerating. In one that is called stationary apparatus, the light sources turn on together, because it was configured this way, and in the other, that is called moving apparatus, which is exactly the same apparatus as in stationary, and which is moving in constant speed, relative to stationary (constant speed, not accelerating), there, apparently, the light sources do not turn on together.

No, the exact electronic or piezo-electronic building of this apparatus is not central. Assume you have materials and electronics, advanced enough to make the central question here the main issue.

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Why are you assuming that time dilation will affect one setup and not the other, when they're both being accelerated together? If the lights are turning on at different times, it's because of the structure of your device, not relativistic affects.

Incidentally, I don't believe spinning the crystal will produce any electricity to light your first bulb. If you apply enough pressure or stress to it, you may achieve some piezo-electric affect, but I doubt it would be enough to light your bulb. But that's not central to the question, so I'll leave it at that.

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It's a clever notion to try to include the use of light in a device to create an exception to time dilation, and I applaud your attempt!

Unfortunately, I'm afraid somebody misinformed you about electricity. While current in a wire is indeed an electromagnetic phenomenon, it's not the same as light moving through a vacuum. Light, as you know, is composed of photons, but electric current is composed of electrons, which have mass, and are therefore subject to relativistic affects.

Still, I like your creative thinking!

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Regarding electricity going through wires in this other experiment - You can change the value of 20X in moving train and 10X in non-moving train to 10X and 10X, or you can leave it the way it is (20X and 10X), either way you get different results: 10X/5=2, 10X/3=3.333, 20X/5=4 so in this experiment, you don't have to relate to affirming or negating time dilation of electricity in wires - You only have to relate to light going through vacuum.

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Doodle17 I just took another look at your question and realized that you added a second train later in your explanation. I don't have time right now to analyze this part of it, but I promise I'll get back to you (unless someone else comes along with an explanation).

Good luck!

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