Relativity of simultaneity objections

[Janus]

i think that what i fail to grasp is WHY ( that is, for what practical reasons ) the light beams will reach the MOVING box doors at the same time, like all of you said. The way i think of it, exactly due to the fact that c is constant and invariant, it will take it more time to reach the front clock than the rear one, because the front one is moving away from it and the back moving towards it. The observer inside the box doesn't know this, but he will notice it when he he sees the front clock stopped at 12:00:11 and the back clock stopped at 12:00:10.

Your not getting what invariant means.

Here's an example. You have two clocks, At first we look them from the perspective of someone at rest with respect to the clocks. A flash of light is emitted from a point halfway between them. It expands outward at c equally in all directions, strikes the clocks and starts them running. They remain in sync

Now we consider the same clocks and the same light flash from the perspective from someone to which the clocks are moving left to right. Again, the flash is emitted from midway between the two clocks and again expands outward at c equally in all directions. This is what 'invariant' means; All inertial frames measure light as moving at c with respect to themselves.

As a result, in this frame, the light hits the left clock before hitting the right clock.

The left clock starts first and then the right clock. The clocks are not in sync. Let me repeat these are the same clocks and the same light flash as in the first example, just considered from a different inertial frame.

As to why this is the case, it is because this is how time and space relate to each other.

I'll try to use an analogy. Absolute time and space, like you are proposing are like the directions North-South and East-West. If you ask someone how far North and far West Chicago is from Miami, everyone gives the same answer.

However, what we have found that time and space aren't like North-South and East-West. They are more like Left-right and forward-backward. If you ask two people how far to the left and how far forward Chicago is from Miami, they will give you different answers if they are facing in different directions relative to each other. And you can't say which one is "really" correct, because the whole concept of Left and Right are dependent of the person.

In the same way, time and space are frame dependent. One frame can say that two events are simultaneous and another will say that they are not in the same way that one person facing one direction will say that two objects are directly to the right and left of each other, while another person facing in a different direction will say that they are not, and that one object is forward of the other.

 

[Mentz114]

i think that what i fail to grasp is WHY ( that is, for what practical reasons ) the light beams will reach the MOVING box doors at the same time, like all of you said. The way i think of it, exactly due to the fact that c is constant and invariant, it will take it more time to reach the front clock than the rear one, because the front one is moving away from it and the back moving towards it. The observer inside the box doesn't know this, but he will notice it when he he sees the front clock stopped at 12:00:11 and the back clock stopped at 12:00:10.

This is absolutist troll rubbish. You've been told a dozen times that the clocks will show the same reading.

 

[Dale]

i think that what i fail to grasp is WHY ( that is, for what practical reasons ) the light beams will reach the MOVING box doors at the same time, like all of you said.

Special relativity is based on two postulates. The second is the invariance of c, but the first is the principle of relativity. The principle of relativity means that the laws of physics do not change depending on which inertial frame you are using. This means that the laws of physics inside a stationary box are exactly the same as the laws of physics inside a moving box.

So, use some procedure to synchronize the clocks and set up the light beams. Then, it doesn't matter if you did that procedure in a moving or stationary box, the result will be the same.

 

[ghwellsjr]

Imagine if we made a computer simulation of this: the simulation KNOWS that the box is moving (because it's a parameter you set, it's in the initial data), thus the light beam will reach it later ( in the front ) than in the back.

So for example if in the computer simulation light moves at an invariant speed of 300pixel / second and the box at 10 pixel / second, the light beam will reach the front door later than the back.

Good idea. I made a series of animations to illustrate how the early scientists explained the Michelson-Morley Experiment (or could have) and how Einstein came up with an alternate explanation.

Take a look, study it, and see if it helps you.

 

[Chestermiller]

sorry, but why will he notice that the clocks did not stop at the same time? The clocks are AT the doors. One clock in the back door one in the front. Once they get hit by the strikes they stop.

If I told you that this is what would be observed experimentally, what would you say? If this same experiment were repeated over and over again, the same result would be obtained. In the frame of reference of the guy on the train, the clock at the front of the train would be found to be hit first, and then the clock at the back of the train.

All the clocks on the ground are synchronized with one another, and all the clocks on the train are synchronized with one another. But, unfortunately, the people on the ground would observe that, according to their reckoning, the clocks on the train are out of sync, and the people on the train would observe that, according to their reckoning, the clocks on the ground are out of sync. This is why two strikes can occur at the same time as reckoned by the people on the ground, while, the people on the train would reckon that the two strikes did not occur at the same time. Who is correct? They both are, according to their respective sets of synchronized clocks.

Another way of look at this is that the people on the ground are able to see partially into the past and partially into the future of the guy at the center of the train.