Something just crossed my mind and it confuses the hell out of me. :)

Let's assume that length contraction and time dilation are real. If that was the case, wouldn't time dilation be an unmeasurable property??

Let me explain:

Let's say you have a clock that is at rest. The clock tells the time by measuring the chemical and/or physical interactions of the materials that make up the the clock. This measured time is, in effect, directly proportional to the speed of the fundamental interactions (electromagnetic and gravitational) that occur inside the clock.

Now, for the sake of argument, let's say that you increase the speed of the clock to .90c. Relativity dictates that reactions in a moving frame of reference are indistingushable from reactions in a stationairy frame of reference. As a result, the reactions in the moving clock should occur at the same speed as the reactions in a stationairy clock. This, in turn, would mean that a clock moving at .90c should, according to relativity, tick at the same speed as a clock that is at rest since a clock does not measure time, it measures the speed of interactions.

Let me explain it in a simpler way. Let's say you have a light clock as shown on this link:

http://www.physics.wustl.edu/~visser/physics-216/notes-light-clock.html

If time dilation and length contraction DID NOT exist, the light clock would tick slower as it's speed increased because the light would have to travel a longer distance through the aether to reach the intended mirror.

According to relativity, length contraction and time dilation would compensate for the increased distance to the mirrors. This would result in the light clock ticking at the same speed, to a stationairy observer, whether the clock is at rest or moving at .90c.

Now let's look at an atomic clock. An atomic clock is like multiple light clocks. All the reactions in an atomic clock are the result of two forces: gravitational and electromagnetic. According to relativity, both of these forces would act at the same speed (invariance in the speed of light) in an atomic clock moving at .90c as they would in an atomic clock at rest due to the effects of time dilation and length contraction. This would mean that a moving atomic clock should tick at the same speed, to a stationairy observer, as the same clock at rest.

As a result, if time dilation and length contraction really did exist, then an moving atomic clock would tick at the same speed as a stationairy clock, to a stationairy observer, since length contraction and time dilation would force the reactions in a moving clock to occur at the same speed as they would in a stationairy clock.

It's kind of ironic. If a moving clock ticks slower than a stationairy clock, then time dilation doesn't exist. However, if a moving clock ticks at the same rate as a stationairy clock, then time dilation does exist. :)

Unfortunately, for relativity, it was proven that a moving clock DOES tick slower than a stationairy clock. This is proof that time dilation DOES NOT exist and that relativity is flawed. :)

Any comments are welcome. :)

Tom

Hi Tom,

This is about frames of reference again. An atomic clock will tick the same rate for EVERYONE observing it next to the clock (i.e. moving along with it). It is only when you throw the atomic clock away at 0.9c, that you see it ticking slower because of two effects:

The finite speed of light issue you mentioned.
Time dilatation (which is an additional effect).


Length contraction also occurs, but it is not relevant to the ticking of the clock (assuming that you purely look at the number of radioactive decays or whatever the precise mechanism is).

What you have to realize is that the moving atomic clock does not notice anything wierd at all; it does not see a time dilatation of itself, it does not see itself get length-contracted. Hence the claim that "time dilatation and length-contraction would force the reactions in a moving clock to occur at the same speed as they would in a stationairy clock" is incorrect.

Bye!

Crisp

Tom,

If you took only a fraction of the effort you spend in your futile and rather pathetic attempts to "debunk" relativity and spent it actually learning the subject, you'd be able to answer all of your own little silly problems. You'd actually understand the subject. Why are you so against the concept of spending a few hours actually learning it?

- Warren

Crisp,

This is about frames of reference again. An atomic clock will tick the same rate for EVERYONE observing it next to the clock (i.e. moving along with it). It is only when you throw the atomic clock away at 0.9c, that you see it ticking slower because of two effects:

You are making a big mistake. Clocks DO NOT measure time, they measure the speed of a reaction. Length contraction and time dilation effect a moving atomic clock in such a way so that the reactions occuring in the moving clock occur at the same speed as if the clock was at rest. Since the speed of the reactions are the same, the moving clock should tick at the exact same rate as a stationairy clock.

Let me give you some examples of different types of clocks and what they use for measurement:

1) Electric clock: electromagnetic interactions (timer and circuits).

2) Analog clock: gravity (swinging or moving weight) and maybe electromagnetic interactions.

3) Atomic clock: gravity (inertia of caesium atoms) and electromagnetic interactions (radiation used to seperate and excite the caesium atoms)

As you can see, almost all clocks use electromagnetic interactions and/or gravity to measure time. They can't measure time directly. Now let's see how electromagnetic interactions and gravity are affected by high speeds:

1) Electromagnetic interaction slows down, but length contraction and time dilation compensate so that the speed of the electromagnetic interaction remains c . Result: No change.

2) Gravity does not increase (as Thed pointed out in another thread, the gravitational mass of an object does not increase as its relative mass increases). Result: No change.

As I indicated before, clocks use the speed of certain reactions to measure time. Most of these reactions are caused by only two forces: electromagnetic force and gravity. As stated above, the electromagnetic force and gravity DOES NOT change as the clock's speed increases. Therefore, the reactions that are caused by the electromagnetic force and gravity DO NOT slow down as the clock travels faster. Since the clock measures the speed of these reactions, and not time, a moving clock, according to relativity, should tick at the same rate as a stationairy clock.

The only thing that I'm not sure of is how a clock using a decay mechanism is influenced by high speeds. If the decay is the result of the electromagnetic interaction, then the decay would occur at the same speed in a moving clock as in a stationairy one. However, I'm not sure how the strong and weak interactions are influenced by high speeds. If relativity is truly relative, then these reactions shouldn't be influenced by speed either. In that were the case, particles would decay at the same rate regardless of their speed.

What do you think about the light clock I referred to in my previous post?? Would it tick slower at high speeds, relative to a stationairy observer, or not?? If it would tick slower, wouldn't that mean that the principle of invariance of light is wrong since the light clock is using the speed of the light to measure time???

Tom

chroot,

If you took only a fraction of the effort you spend in your futile and rather pathetic attempts to "debunk" relativity and spent it actually learning the subject, you'd be able to answer all of your own little silly problems. You'd actually understand the subject. Why are you so against the concept of spending a few hours actually learning it?

I've been at sciforums for almost a year now, and most of the discussions I had here were pertaining to relativity. So I think that, over the last year, I spent more than a few hours learning relativity. Instead of learning it from books, I learned it from some very educated individuals on these forums.

Now back to the subject of this thread, I am stating that this is a catch 22 for relativity: Relativity says that time dilation occurs at high speeds, but this same time dilation would influence a clock in such a way that the clock moving at high speeds wouldn't tick any slower.

As an example of this, I provided the link to the light clock in one of my previous posts.

What do you think about the light clock?? Do you think it would tick slower, relative to a stationairy observer, or not?? If it would run slower, why???

Tom

Hi Tom,

"Electromagnetic interaction slows down, but length contraction and time dilation compensate so that the speed of the electromagnetic interaction remains c . Result: No change."

This is not correct. Length contraction and time dilatation do not compensate for the speed of the electromagnetic interaction to remain c. The speed of the electromagnetic interaction is c and from this you get time dilatation and length contraction (in the proper frames of reference)...

And also Tom, when you use the words "length contraction" and "time dilatation", you are using special relativity. Then you also must use/accept that c is constant.

And once again, purely logically speaking, you cannot debunk a theory from within its own framework, your attempts to prove that relativity is inconsistent through relativistic thought experiments are doomed to fail by logical arguments (and I mean logical in the mathematical sense). The only way to prove relativity wrong is to come up with an alternative, or with an experiment that shows relativity is incorrect (we have those by the way ;)).

Bye!

Crisp

Crisp,

This is not correct. Length contraction and time dilatation do not compensate for the speed of the electromagnetic interaction to remain c. The speed of the electromagnetic interaction is c and from this you get time dilatation and length contraction (in the proper frames of reference)...

Let's, for the sake of argument, assume that the omnidirectional speed of light is c in all frames of reference. Wouldn't this mean that the light clock ticks at the same rate if it's moving at .90c as it would tick if it is at rest?? After all, the light clock measures time using the speed of light, and as you indicated, the speed of light does not change. Since the speed of light doesn't change as the light clock increases its speed, why would its measurements of time change??

If you assume that time dilation and length contraction don't exist, then the light clock would tick slower as it's speed increases because the speed of the light in the clock, relative to the clock, would change.

However, if the speed of light is constant at all speeds, wouldn't the light clocks measurement of time (using light speed) be constant at all speeds as well??

If the answer to the above question is yes, why wouldn't the same apply to all clocks, including atomic clocks??

You still didn't answer my question. :) To a relative abserver, would a moving light clock tick slower than one that is at rest?? And if the answer is yes, then how would the light clock tick slower when it uses the speed of light as a measurement of time, and as you clearly stated, the speed of light is constant at all speeds?? :)

The only way to prove relativity wrong is to come up with an alternative, or with an experiment that shows relativity is incorrect (we have those by the way ).

Now that sounds interesting. :). Do you have any links where I might find these experiments??

Tom

Tom:

You're getting muddled.

<i>Let's, for the sake of argument, assume that the omnidirectional speed of light is c in all frames of reference. Wouldn't this mean that the light clock ticks at the same rate if it's moving at .90c as it would tick if it is at rest?? After all, the light clock measures time using the speed of light, and as you indicated, the speed of light does not change.</i>

You're right that the speed of light doesn't change. You'll know from the derivation of the time dilation equation from the light clock that the light has further to travel when the clock is moving compared to when it is stationary. Therefore, the clock ticks slower when it is moving.

You really need to read up on basic relativity.

Hi Tom,

Sorry, I don't have a lot of time to go into detail on your question now, I will get back to you this weekend (be sure to remind me through private messaging or something if I forget about it)...

An article on the experiment I was referring to is <A HREF="http://xxx.lanl.gov/abs/quant-ph/9811019">here</A> (Tunneling Times and Superluminality: a Tutorial). However, I just reread the abstract and realize that I should think once more if it really is inconsistent with relativity (perhaps its also mentioned in the article, I don't have time to reread it here). At first sight it seems to be, since the group velocity of the photon package travels through the tunnel faster than light (which is something else than the phase velocity FTL which is consistent with relativity).

Anyway, I will get back to you on this.

Bye!

Crisp

James,

You're right that the speed of light doesn't change. You'll know from the derivation of the time dilation equation from the light clock that the light has further to travel when the clock is moving compared to when it is stationary. Therefore, the clock ticks slower when it is moving.

Your mixing the absolute (aether) model with relativity.

In the absolute model, where length contraction and time dilation doesn't exist, the light clock would tick slower because, as you pointed out, the light has further to travel when the clock is moving.

However, according to relativity, time dilation and length contraction compensate for the increased distance that the light must travel as the light clock moves. (remember the principle of invariance of light). This would make the speed of the light between the mirrors remain unchanged regardless of the speed of the light clock. And since the light clock is not directly measuring time, but measuring the speed of light between the mirrors, the light clock should, according to relativity, tick at the same rate regardless of the speed it is travelling. This effect should apply to all atomic clocks, as well. (if relativity is correct)

Tom

James and Crisp,

Nevermind. I found out that I was wrong. I forgot that time dilation and length contraction are only local phenomena. I mistakenly applied them to a stationairy observer.

Relativity is really a pain in the ass. :)

Tom

Now, for the sake of argument, let's say that you increase the speed of the clock to .90c. Relativity dictates that reactions in a moving frame of reference are indistingushable from reactions in a stationairy frame of reference. As a result, the reactions in the moving clock should occur at the same speed as the reactions in a stationairy clock. This, in turn, would mean that a clock moving at .90c should, according to relativity, tick at the same speed as a clock that is at rest since a clock does not measure time, it measures the speed of interactions.
consider this:

I'm on a train in uniform motion. You are standing on the platform. Just as I draw level with you I drop a stone (we'll ignore wind resistance). From your perspective you will see fall downwards and sideways with the same velocity as the train. However, from my perspective the stone will fall in a straight line because I am moving sideways with the stone.

Relativity does say that reactions (ie. the laws of physics) are the same in every reference frame, but the sacrifice of this is that observers in different reference frames will see different things, which is precisely what we see in the real world.

Your mistake is in this line:Relativity dictates that reactions in a moving frame of reference are indistingushable from reactions in a stationairy frame of referenceRelativity dictates that people will see different things if they are in different reference frames because the laws of physics must remain the same for every reference frame.

You're mixing reference frames (I just did this myself in another thread so don't feel aggrieved).

Consider this:
I am standing on the ground with my watch on. I look at my watch. It's working fine. I accelerate up to .9c. I look at my watch. It is ticking fine. The laws of physics are the same regardless of my velocity. My watch and myself are in the same reference frame. Therefore my watch "sees" what I see.

Now consider this:
I am standing on the ground with my watch on. I look at my watch. It's working fine. I take my watch off and put it in the spaceship with a camera pointing at it to send me a picture of my watch every 1/25th of a second, and accelerate it up to .9c. I look at the picture on my screen to see what my watch is doing. It's running very slow (ignoring the time delay that would occur for the signal from the camera to reach you, for each hour on my clock, the watch will advance only 11.4 minutes). My watch and myself are not in the same reference frame. I am at rest and the watch is moving at .9c. Therefore my watch "sees" something different to what I see.

I hope that helps.

kind regards
Paul