posted, 16 October 2015.
The following thought experiment has similar base with the "version 1".
Length contraction thought experiment, figures 30, 31, 32.
We have a double-track railway and we have put one wagon on each rail track(figure 30).
The two wagons are totally identical and are having the same length when they are not on the move relative to each other.
A few humans are inside on each wagon.
At the front and at the back end of each wagon we have put two sensors. Sensors A-B for the wagon A and sensors C-D for the
wagon B( figure 30).
The sensors are affixed on the sides of the wagons which they are between the two rail tracks.
Each sensor is a long cylindrical object with a diameter of 20 centimetres, and it almost reaches the other wagon.
The sensors will be positioned perpendicular to the side of the wagon in which they are affixed.
{ On the figure 30, i drew the sensors not perpendicular in order for the image to look like if the sensors collide with each other, because the one wagon is moving towards the other and the sensors will really collide, and also because i have put the one wagon exactly next to the other, and due to that i could not drew the sensors differently because the two wagons are having exactly the same length. On the figures 31 & 32 i drew the sensors perpendicularly.}
The wagon B is not going to move relative to the ground.
The wagon A will move at a speed close to the speed of light relative to the ground and it will pass next to the wagon B.
So, the relative speed between the two wagons will be close to the speed of light.
When the two wagons are in relative motion with each other and are passing the one next to the other, the sensors of the one wagon will collide with the sensors of the other wagon.
The four sensors collide as pairs.
The one pair is the sensors A & C, and the other pair is the sensors B & D.
We will put the sensors A & C at 150 centimetres from the ground, and the sensors B & D at 120 centimetres from the ground.
This means that the sensor A can collide only with the sensor C, and the sensor B can collide only with the sensor D.
Of course the sensors will be destroyed by the collision, but we don't care about that.
On each wagon we have put two caesium atomic clocks on the corners where the sensors are( figure 30).
Each sensor is connected with the atomic clock on its corner.
In other words we can say that, each sensor is a part of an atomic clock.
Each sensor will act as start button for each atomic clock, during the collision with the other sensor.
Each atomic clock displays the time in digital-style( figure 30).
Normally the clocks are not displaying time.
Each caesium atomic clock will start counting time( displaying time), when its sensor collide with the sensor of the other wagon.
Each sensor will activate its own atomic clock, at the time of the collision with the other sensor.
The atomic clocks will be activated by the movements and the vibrations on the base of the sensors, that are produced by the collision.
When the sensors of a pair collide with each other, the atomic clock on each sensor will be activated.
The one pair is the sensors A & C, and the other pair is the sensors B & D.
For example, when the sensors A & C collide with each other, the atomic clocks on the two sensors will be activated.
The same will happen when the sensors B & D collide.
{ We can use normal clocks, but it is better to use atomic clocks because they can measure much smaller fractions of a second. }
{ We can use normal clocks, but it is better to use atomic clocks because they can measure much smaller fractions of a second. }
We start the experiment.
The wagon A is moving at a speed close to the speed of light relative to the ground and approaches the wagon B, or in other words we can say that the two wagons approaching one another at a relative speed close to the speed of light.
On the figure 31 we see which is the reality on the frame of reference of the wagon B, according to the theory of relativity and the scientific community.
According to the theory of relativity, the reality for the wagon B is that the wagon A is really contracted.
On the left side of the figure 31 we see that the wagon A approaches the wagon B.
The sensor B passes below the sensor C and there is no collision.
On the right side of the figure 31 we see what happens while the wagon A continues to move.
We see that the sensors C & A collide before the sensors D & B.
If the wagon A is really contracted, the only possible order of collisions is: first the collision of the pair C & A, and second the collision of the pair D & B, and this has nothing to do with what someone sees, meaning that has nothing to do with the ''relativity of simultaneity'', but it has to do with the fact that the wagon A is really contracted!!!!!
The fact that the wagon A is actually contracted, determines which pair of sensors will collide first!!!!!!!!!!
The fact that we say that the wagon A is actually contracted, determines that the collision of the sensors C & A will occur first(figure 31)!!!!!
The fact that the wagon A is actually contracted, determines which pair of sensors will collide first!!!!!!!!!!
The fact that we say that the wagon A is actually contracted, determines that the collision of the sensors C & A will occur first(figure 31)!!!!!
Therefore, the sensors C & A will actually collide before the sensors D & B, and we know that this is the actual order of collisions, regardless if we are looking towards the collisions or not!!!!!!!!!
This means that the atomic clocks on the sensors C & A will be activated before the clocks on the sensors D & B.
This means that the atomic clocks on the sensors C & A will be activated before the clocks on the sensors D & B.
When the collision between the sensors C & A occur, each sensor will activate its own atomic clock.
The collision between two sensors is one thing, one event that happens simultaneously on the two sensors!!!!!!
Therefore, when two sensors collide, they will activate their clocks simultaneously.
It will be completely illogical if we say something different!!!!!!!!
The simultaneous activation of the clocks on the sensors C & A has nothing to do with the ''relativity of simultaneity''.
In order for the clock on the sensor C to be activated, its sensor must collide with the sensor A, and in order for the clock on the sensor A to be activated, its sensor must collide with the sensor C!!!!!!!!!!!!!!!!!!
Therefore, the collision of the two sensors, has the result of the simultaneous activation of the clocks on the two sensors, and this has nothing to do with what someone sees, meaning that has nothing to do with the ''relativity of simultaneity''!!!!!
The simultaneous activation of the clocks on the sensors C & A has nothing to do with the ''relativity of simultaneity''.
In order for the clock on the sensor C to be activated, its sensor must collide with the sensor A, and in order for the clock on the sensor A to be activated, its sensor must collide with the sensor C!!!!!!!!!!!!!!!!!!
Therefore, the collision of the two sensors, has the result of the simultaneous activation of the clocks on the two sensors, and this has nothing to do with what someone sees, meaning that has nothing to do with the ''relativity of simultaneity''!!!!!
Can we say that when the sensor C activate its clock, the sensor A does not simultaneously activate its own clock?????????
Of course we cannot say that!!!!!
When the sensor C activate its clock, the sensor A simultaneously activates its own clock.
When the sensor C activate its clock, the sensor A simultaneously activates its own clock.
So the atomic clock of the sensor C starts counting ''time'', and simultaneously the atomic clock on the sensor A starts also to counting ''time''.
The collision between the sensors D & B will occur after the collision between the sensors C & A.
When the collision between the sensors D & B occur, each sensor will activate its own atomic clock.
So the atomic clock of the sensor D starts counting ''time'', and simultaneously the atomic clock on the sensor B starts also to counting ''time''.
To summarise, what will happen is that the atomic clocks on the sensors A & C will be activated before the atomic clocks on the sensors B & D(figure 31)!!!!!!!!!!!
To summarise, what will happen is that the atomic clocks on the sensors A & C will be activated before the atomic clocks on the sensors B & D(figure 31)!!!!!!!!!!!
So, the sensors C & A collide and the atomic clocks on the sensors C & A are activated simultaneously, and when the clock on the sensor A is activated, the clock on the sensor B has not being activated yet(figure 31), because also the clock on the
sensor D has not being activated yet, which means that the clock on the sensor A will display more time than the clock on the
sensor B, because the clock on the sensor A will be activated before the clock on the sensor B!!!!!!!!
So, the atomic clock on the sensor C will always display more milliseconds or microseconds or nanoseconds than the atomic clock on the sensor D, because the clock on the sensor C has been activated first.
sensor D has not being activated yet, which means that the clock on the sensor A will display more time than the clock on the
sensor B, because the clock on the sensor A will be activated before the clock on the sensor B!!!!!!!!
So, the atomic clock on the sensor C will always display more milliseconds or microseconds or nanoseconds than the atomic clock on the sensor D, because the clock on the sensor C has been activated first.
And the reality on the wagon A must be, that the atomic clock of the sensor A will always display more milliseconds or microseconds or nanoseconds than the atomic clock on the sensor B, because the clock on the sensor A will be activated simultaneously with the clock on the sensor C, and the clock on the sensor B will be activated simultaneously with the clock on the sensor D, and that means that the clock on the sensor A will be activated before the clock on the sensor B( see figure 31).
Why we say all that???????
Because, when two sensors collide they will activate their clocks simultaneously, and the clocks on the sensors C & A will bee activated before the clocks on the sensors D & B.
Can we disagree with that??????????
Can we say that when the sensor C activates its clock, the sensor A does not simultaneously activate its own clock?????????
Can we say that the clock on the sensor B will not be activated simultaneously with the clock on the sensor D??????
Of course not!!!!!!
Therefore, the clock on the sensor A has been activated simultaneously with the clock on the sensor C, and both have been activated before the clocks on the sensors D & B.
There is the following fact with which no one can disagree:
The two atomic clocks that a wagon has, are always stationary relative to each other, therefore, if the one clock is activated first, it will always display more ''time'' than the other clock.
On the figure 32 we see which is the reality on the reference frame of the wagon A, according to the theory of relativity and the scientific community.
According to the scientific community, the reality for the wagon A is that the wagon B is really contracted.
On the left side of the figure 32 we see that the wagon A approaches the wagon B.
{ On the wagon A the reality is that the wagon B is moving, and so instead of saying that the wagon A approaches the wagon B, we can say that the wagon B approaches the wagon A, or we can say that the two wagons approaching one another. }
We see that the sensor B passes below the sensor C and there is no collision.
On the right side of the figure 32 we see what happens while the relative motion between the two wagons continues.
We see that the sensors B & D collide before the sensors A & C.
But of course this is the opposite order of collisions than the reality according to the wagon B!!!!!!!
The fact that the wagon B is actually contracted, determines which pair of sensors will collide first, and this has nothing to do with the ''relativity of simultaneity''!!!!!!!!!!
Therefore, according to the wagon A, the sensors B & D will actually collide before the sensors A & C, and this is the actual order of collisions, regardless of what someone sees, because the wagon B is actually contracted!!!!!!!!!
This means that the atomic clocks on the sensors B & D will be activated before the clocks on the sensors A & C.
This means that the atomic clocks on the sensors B & D will be activated before the clocks on the sensors A & C.
When the collision between the sensors B & D occur, each sensor will activate its own atomic clock.
The collision between the two sensors is one ''thing'', one event that happens simultaneously on the two sensors.
Therefore the sensors B & D will activate their clocks simultaneously.
The collision of the two sensors, has the result of the simultaneous activation of the clocks on the two sensors, and this is a fact regardless of what someone sees, meaning that has nothing to do with the ''relativity of simultaneity''!!!!!
The collision of the two sensors, has the result of the simultaneous activation of the clocks on the two sensors, and this is a fact regardless of what someone sees, meaning that has nothing to do with the ''relativity of simultaneity''!!!!!
Can we say that when the sensor B activate its clock, the sensor D does not simultaneously activate its own clock?????????
Of course we cannot say that!!!!!!!!!!
When the sensor B activate its clock, the sensor D simultaneously activates its own clock.
So the atomic clock of the sensor B starts counting ''time'', and simultaneously the atomic clock on the sensor D starts also to counting ''time''.
The collision between the sensors A & C will occur after the collision between the sensors B & D.
When the collision between the sensors A & C occur, each sensor will activate its own atomic clock.
So the atomic clock of the sensor A starts counting ''time'', and simultaneously the atomic clock on the sensor C starts also to counting ''time''.
To summarise, what will happen is that the atomic clocks on the sensors B & D will be activated before the atomic clocks on the sensors A & C(figure 32)!!!!!!!!!!!
To summarise, what will happen is that the atomic clocks on the sensors B & D will be activated before the atomic clocks on the sensors A & C(figure 32)!!!!!!!!!!!
So, according to the reality for the wagon A, the atomic clock on the sensor B will always display more milliseconds or microseconds or nanoseconds than the atomic clock on the sensor A, because the clock on the sensor B has been activated first.
And the reality on the wagon B must be, that the atomic clock of the sensor D will always display more milliseconds or microseconds or nanoseconds than the atomic clock on the sensor C, because the clock on the sensor D will be activated simultaneously with the clock on the sensor B, and the clock on the sensor C will be activated simultaneously with the clock on the sensor A, and that means that the clock on the sensor D will be activated before the clock on the sensor C( see figure 32).
But this is the opposite than the expected reality according to the wagon B!!!!!!!!
Which of the two is going to happen????????
If we accept that the length contraction is real and reciprocal, we have the following assumptions that are leading to a contradiction:
According to the reality on the wagon A, the sensors B & D will collide before the sensors A & C, but according to the reality on the wagon B, the sensors A & C will collide before the sensors B & D, meaning that according to the wagon B, the clocks on the sensors A & C will be activated before the clocks on the sensors B & D, but according to the wagon A, the clocks on the sensors B & D will be activated before the clocks on the sensors A & C!!!!!!
And the humans on the two wagons agree that the clocks on each pair of sensors( pair A-C , pair B-D ) will be activated simultaneously, because it will be completely illogical if we say something different!!!!!!!
The question that we have to answer is, which of the two atomic clocks that each wagon has, will display more time when the two wagons have moved away from each other??????
The answer to that question is ONE!!!!!!!!
If someone believes that the reality on the wagon A will be that the clock on the sensor B will be activated before the clock on the sensor A, and the reality on the wagon B will be that the clock on the sensor C will be activated before the clock on the sensor D, this means that we have to accept that when two sensors collide, the clocks on the two sensors will not be activated simultaneously, and of course we cannot accept that!!!!!
When two sensors collide, the clocks on the two sensors will be activated simultaneously, and that fact connects the realities of the two wagons!!!!!
Imagine that we are on the wagon B, and the clock on the sensor C is activated because the sensor C collides with the sensor A(figure 31).
When the clock on the sensor C is activated, simultaneously the clock on the sensor A is activated, and we cannot accept any different about that!!!!!!!!!
If we accept, according to the special relativity theory, that the reality on the wagon A is that the clock on the sensor B has already been activated before the clock on the sensor A, this means that we on the wagon B, must accept that the clock on the sensor B has been activated without the collision of the sensors B & D, and the clock on the sensor B will not be activated simultaneously with the clock on the sensor D!!!!!!!
And of course we cannot accept that!!!!!!!
If we are on the wagon B and something is happening to our wagon, something else is actually happening to the other wagon!!!!!!
At the moment that the activation of the clock on the sensor C is happening on the wagon B, something else is happening to the wagon A, and something else will happen after a while on the wagon A!!!!!!!
If we are on the wagon B, at the moment that the activation of the clock on the sensor C is actually happening on the wagon B, can we say that the activation of the clock on the sensor B has actually already happened on the wagon A???????
Of course we cannot accept that!!!!
Let's summarise in order to understand easier the problem:
The answer to that question is ONE!!!!!!!!
If someone believes that the reality on the wagon A will be that the clock on the sensor B will be activated before the clock on the sensor A, and the reality on the wagon B will be that the clock on the sensor C will be activated before the clock on the sensor D, this means that we have to accept that when two sensors collide, the clocks on the two sensors will not be activated simultaneously, and of course we cannot accept that!!!!!
When two sensors collide, the clocks on the two sensors will be activated simultaneously, and that fact connects the realities of the two wagons!!!!!
Imagine that we are on the wagon B, and the clock on the sensor C is activated because the sensor C collides with the sensor A(figure 31).
When the clock on the sensor C is activated, simultaneously the clock on the sensor A is activated, and we cannot accept any different about that!!!!!!!!!
If we accept, according to the special relativity theory, that the reality on the wagon A is that the clock on the sensor B has already been activated before the clock on the sensor A, this means that we on the wagon B, must accept that the clock on the sensor B has been activated without the collision of the sensors B & D, and the clock on the sensor B will not be activated simultaneously with the clock on the sensor D!!!!!!!
And of course we cannot accept that!!!!!!!
If we are on the wagon B and something is happening to our wagon, something else is actually happening to the other wagon!!!!!!
At the moment that the activation of the clock on the sensor C is happening on the wagon B, something else is happening to the wagon A, and something else will happen after a while on the wagon A!!!!!!!
If we are on the wagon B, at the moment that the activation of the clock on the sensor C is actually happening on the wagon B, can we say that the activation of the clock on the sensor B has actually already happened on the wagon A???????
Of course we cannot accept that!!!!
Let's summarise in order to understand easier the problem:
According to the reality on the wagon B(figure 31), the collision of the sensors A & C will occur before the collision of the sensors B & D.
When the sensors A & C collide, the clocks on the two sensors will be activated.
That means that the clock on the sensor A will be activated before the clock on the sensor B, meaning that the clock on the sensor A will display more time that the clock on the sensor B!!!!!!!!
But if we accept that the length contraction is real and reciprocal, then according to the reality on wagon A(figure 32), the sensors B & D will collide before the sensors A & C, which means that the clock on the sensor B will be activated before the clock on the sensor A, meaning that the clock on the sensor B will display more time than the clock on the sensor A!!!!!!!
So, which of the two will happen?????????
If the reality on the wagon B is that the clock on the sensor C displays more time than the clock on the sensor D, because the clock on the sensor C will be activated before the clock on the sensor D, then on the wagon A, the reality must be that the clock on the sensor A will display more time than the clock on the sensor B, because the clock on the sensor A will be activated simultaneously with the clock on the sensor C, and that means that the clock on the sensor A will be activated before the clock on the sensor B!!!!!!!!!!!
Let's for example say that we are on the wagon B, and the clock on the sensor C is activated because the sensor C collides with the sensor A ( figure 31).
At the moment of activation of the clock on the sensor C, the clock on the sensor A is also simultaneously activated, a simultaneous activation caused by the collision of the two sensors!!!!!
At the moment that the clocks on the sensors C & A are activated(figure 31), the clock on the sensor B has not been activated yet and also the clock on the sensor D has not been activated yet, because the clocks on the sensors D & B will be activated simultaneously by the collision of the sensors D & B, which will occur after the collision of the sensors C & A.
At the moment that the clocks on the sensors C & A are activated(figure 31), the clock on the sensor B has not been activated yet and also the clock on the sensor D has not been activated yet, because the clocks on the sensors D & B will be activated simultaneously by the collision of the sensors D & B, which will occur after the collision of the sensors C & A.
And this means that the clock on the sensor A will be activated before the clock on the sensor B,
which means that the clock on the sensor A will display more time than the clock on the sensor B.
which means that the clock on the sensor A will display more time than the clock on the sensor B.
But if we accept that the length contraction is real and reciprocal effect, this cannot be happening, because according to the wagon A(figure 32), the actual result is that the clock on the sensor B will be activated before the clock on the sensor A!!!!!!!
We have two different expected realities:
According to the reality on the wagon B, the clock on the sensor C will always display more ''time'' than the clock on the sensor D, because the clock on the sensor C will be activated first.
Also according to the reality on the wagon B(figure 31), the clock on the sensor A will always display more ''time'' than the clock on the
sensor B, because the clock on the sensor A will be activated simultaneously with the clock on the sensor C, and the clock on the sensor B will be activated simultaneously with the clock on the sensor D, meaning that the clock on the sensor A will be activated before the clock on the sensor B.
sensor B, because the clock on the sensor A will be activated simultaneously with the clock on the sensor C, and the clock on the sensor B will be activated simultaneously with the clock on the sensor D, meaning that the clock on the sensor A will be activated before the clock on the sensor B.
But the reality on the wagon A is the opposite!!!!!!!!!!
According to the reality on the wagon A, the clock on the sensor B will always display more ''time'' than the clock on the sensor A, because the clock on the sensor B will be activated first.
Also according to the reality on the wagon A(figure 32), the clock on the sensor D will always display more ''time'' than the clock on the
sensor C, because the clock on the sensor D will be activated simultaneously with the clock on the sensor B, and the clock on the sensor C will be activated simultaneously with the clock on the sensor A, meaning that the clock on the sensor D will be activated before the clock on the sensor C.
sensor C, because the clock on the sensor D will be activated simultaneously with the clock on the sensor B, and the clock on the sensor C will be activated simultaneously with the clock on the sensor A, meaning that the clock on the sensor D will be activated before the clock on the sensor C.
Which of the two will happen?????????
{ The two atomic clocks that a wagon has, are always on the same frame of reference, therefore, if the one clock is activated first, it will always display more ''time'' than the other clock }
The important that we must have in mind is that, in order for an atomic clock to be activated, its sensor must collide with the sensor of another atomic clock.
This means that when two sensors collide, the atomic clocks on the two sensors will be
activated simultaneously.
It cannot be otherwise.
The important that we must have in mind is that, in order for an atomic clock to be activated, its sensor must collide with the sensor of another atomic clock.
This means that when two sensors collide, the atomic clocks on the two sensors will be
activated simultaneously.
It cannot be otherwise.
When we say that two atomic clocks will be activated simultaneously, this is not a case where someone will just see a simultaneous activation of the clocks.
This is a case where we don't have any doubt about the fact that when two sensors collide, the clocks on the two sensors will be activated simultaneously.
It will be completely illogical if we say something different.
We know what is going to happen, and there is no need to look towards the clocks or the sensors.
Another important ''thing'' that we must have in mind is that, if we say that a wagon is actually contracted, that fact is the one that determines which pair of sensors will collide first, and this has nothing to do with what someone sees!!!!!!
This is a case where we don't have any doubt about the fact that when two sensors collide, the clocks on the two sensors will be activated simultaneously.
It will be completely illogical if we say something different.
We know what is going to happen, and there is no need to look towards the clocks or the sensors.
Another important ''thing'' that we must have in mind is that, if we say that a wagon is actually contracted, that fact is the one that determines which pair of sensors will collide first, and this has nothing to do with what someone sees!!!!!!
The only thing that we want to find is, which of the two atomic clocks that a wagon has, will be activated first????
When the two wagons have moved away from each other, someone can go and look at the clocks on each wagon and see what time they display.
If the length contraction is real, the two clocks that a wagon has will not display the same time, because the one clock will be activated first.
But as we can see on this thought experiment, if we accept the fact that the length contraction is real and reciprocal, we have two different expected realities!!!!!!!!!!!
The scientists which believe that the time dilation due to relative motion is real (i disagree with that), they will say that the atomic clocks of each pair of sensors( pair A-C &
pair B-D) will not display the same time, even though they will be activated simultaneously, because the ''time'' on the one wagon runs slower than the other wagon.
pair B-D) will not display the same time, even though they will be activated simultaneously, because the ''time'' on the one wagon runs slower than the other wagon.
For example, they will say that the clock on the sensor A will not display the same time with the clock on the sensor C, although they were activated simultaneously, because they are not on the same wagon and the ''time'' on the one wagon runs slower, meaning because of ''time dilation''(of course i say that the time dilation due to relative motion does not exist).
Do not focus on that!!!!!
On this thought experiment we don't want to find if the ''time'' on the two wagons is different!!!!!
On this thought experiment we compare the two clocks that a wagon has, meaning that we want to compare the clock on the sensor A with the clock on the sensor B, and the clock on the sensor C with the clock on the sensor D.
Even if the someone believes that the time on the one wagon runs slower, that does not change the fact that the two clocks which a wagon has, will not display the same time because they are not activated simultaneously, which will happen if we accept that the length contraction is real!!!!!!
The clocks on the sensors A & B are not going to be activated simultaneously and so they will not display the same time, and the same applies to the clocks on the sensors C & D.
On this thought experiment we are not trying to find if the ''time'' on the two wagons is different.
On this thought experiment, we only want to find which of the two atomic clocks that a wagon has, will be activated first, meaning which of the two atomic clocks that each wagon has, will always display more time???????
An important note.
Someone can make the following observation:
The observation is that, it will be almost impossible to construct two totally identical wagons, and it will be almost impossible to make the distance between the sensors A & B to be exactly the same with the distance between the sensors C & D.
And so that means, that we have to accept the fact that the distance between the sensors A & B will be slightly different than the distance between the
sensors C & D.
sensors C & D.
So, what happens then???????
Answer:
If we say that the length contraction is real, even if the length of the two wagons is not exactly the same when they are not in relative motion with each other, it doesn't make any difference and the assumptions of the thought experiment will still be contradicting.
For example, let's say that when the two wagons are not in relative motion with each other, intentionally we make the one wagon larger, and the distance between the sensors A & B is larger by 1 millimetre than the distance between the sensors C & D.
When the percentage of the length contraction of the wagons is 20-30-40-50 per cent, the 1 millimetre will not make any difference to the contradicting assumptions of the thought experiment!!!!!!!!!!!
For example, if the wagons are having 10 metres length and the contraction is 30 %, the 1 millimetre will not make a difference because the contraction of the wagons will be three metres.
If there is no length contraction, only then, the 1 millimetre will make a difference.
If there is no length contraction, the real order of the collisions between the sensors depends of the 1 millimetre difference in length.
And of course in that case, meaning if the length contraction is not happening, the humans on the two wagons will agree about the order of the collisions between the sensors, and they will also agree about what the atomic clocks on the two wagons display.
We can create a different version of this thought experiment.
Instead of two wagons in relative motion, we can have two spaceships in relative motion.