**GatheringKnowledge**

3. Let's consider a simple scenario: There are 3 objects - A (red sphere), B (blue sphere) and C (yellow sphere). A and B are moving towards eachother at 0,25c. At t=0 distance between A and B is equal to 2su (space units), while object C is located right in the middle of that distance and remains stationary - so, from the perspective of C, all 3 objects will cross the same point in 1D space at t=4. The point is to begin from the perspective of stationary C and use the rules of SRT, to change the perspective to A, only to use this result as a base, while switching the perspective once more to B...

3. Let's consider a simple scenario: There are 3 objects - A (red sphere), B (blue sphere) and C (yellow sphere). A and B are moving towards eachother at 0,25c. At t=0 distance between A and B is equal to 2su (space units), while object C is located right in the middle of that distance and remains stationary - so, from the perspective of C, all 3 objects will cross the same point in 1D space at t=4. The point is to begin from the perspective of stationary C and use the rules of SRT, to change the perspective to A, only to use this result as a base, while switching the perspective once more to B...

Here's a spacetime diagram for the inertial frame of object C (yellow sphere).

Here's an animation of the same scenario in 2D space and with time dimension expressed in frame numbers - 10 frames is here equal to 1tu (time unit)

(you can ignore for now everything except the spheres)

And here's the result, which we'll get by using the rules of classic Galilean relativity, to see this scenario from the perspective of red sphere A. Of course, since after the Galilean transformation of coordinates, symmetry of motion will be maintained in all frames, there's no sense to show you the diagram for blue sphere B, as it will be the same, as the results below - only in reverse...

There was already one person, who tried to deal with my challenge and gave me the results, which he got after using Lorentz transformation, to switch between the perspectives. Problem is, that he started from the result, which I've got after using the Galilean transformation to show the perspective of stationary A (the ones above) and used it as base, to show other 2 perspectives - and since he used as well the formula of Einstein's velocity addition, there was no symmetry of motion for the inertial frame of C (yellow sphere), on which I based this entire scenario... Here are the results with his commentary:

*"Blue (A), Green (B) moving 0.25c, and Red (C) moving at 0.5c"*

"It's probably not super apparent at these relative velocities, but I think you can see here that the slopes of the red and blue lines are not purely mirror images of each other. Red's slope (C) is just a little bit steeper than Blue's (A), representing its slightly greater speed in this frame (0.286c vs 0.25c)"

"I included a frame with C stationary just for completeness. This one makes it really clear how the starts and ends of the objects' paths are not simultaneous in every frame. It should also be clear that at any given moment in their paths, Blue (A) is not quite twice as far from Red (C) as Green (B) is, owing to the fact that the relative velocity of Green (0.286c) is more than half that of Blue (0.5c) here."

"It's probably not super apparent at these relative velocities, but I think you can see here that the slopes of the red and blue lines are not purely mirror images of each other. Red's slope (C) is just a little bit steeper than Blue's (A), representing its slightly greater speed in this frame (0.286c vs 0.25c)"

"I included a frame with C stationary just for completeness. This one makes it really clear how the starts and ends of the objects' paths are not simultaneous in every frame. It should also be clear that at any given moment in their paths, Blue (A) is not quite twice as far from Red (C) as Green (B) is, owing to the fact that the relative velocity of Green (0.286c) is more than half that of Blue (0.5c) here."

It's funny, how he considered those results as valid ones, while the entire scenario got completely broken. I won't discuss here, how wrong those diagrams are, as there's a limit of post lenght - but anyone, who knows, how to read those diagrams, should be able to make his own conclusions. Anyway, it might be possible, that if he would begin from the frame of stationary yellow sphere, the symmetry of motion would be maintained, while changing perspective between red and blue spheres - because now, this symmetry is completely gone. In relation to yellow sphere, objects A and B are moving at the same speed (0,25c), so for them velocities of moving objects have to be the same, just as the distances, which they pass in a given time...

If there's no way to get a valid result for such simple scenario, then Einstein obviously fooled everybody. But I want to give everyone a second chance in dealing with my scenario. If there's someone, who wants to defend the Special Relativity, all he needs to do, is to show me some spacetime diagrams, where after using the Lorentz transformation, we will get reversed results, while switching between the perspectives of red and blue spheres - so the symmetry of relative motion will be maintained in all frames. Using frame of stationary C as base for other 2 diagrams, will be considered, as cheating...