This thread is intended for James, Billy T, Tom2, Janus58 and everyone else who still support Relativity. After all this time on sciforums, MacM has definitely proven that relativity is invalid using only a simple thought experiment. In his thread, MacM explains what I call the triplet paradox: http://www.sciforums.com/showthread.php?t=47015 In MacM's thought experiment, there are three observers (triplets) on Earth. Let's call them observer A, B, and C, and each observer has an atomic clock that is in sync with the other observer's clocks. The three observers then start their clocks. Observer A stays on Earth, while observer B and C travel at relativistic speeds away from each other (and observer A). After observer B and C both travel one light year from observer A, they stop their clocks and send a light signal to observer A. When observer A gets the signals, he stops his clock and subtracts one year from his clock. Finally, observers B and C head back to Earth, and they compare their times on their clocks with the time on observer A's clock. Question: If ta, tb, and tc are the times on observer A's, B's, and C's clocks, which of the values (ta, tb, or tc) will be the largest, and which will be the smallest? James has stated, in another thread, that tb and tc would be equal, while ta would be larger. This would imply that time dilated for observer B and C relative to observer A, which is exactly what relativity dictates. However relative to observer B, time should have dilated for observer A and C, and for observer C, time should have dilated for observer A and B. In other words, relativity dictates that: In A's frame of reference ta>tb=tc In B's frame of reference tb>ta>tc in C's frame of reference tc>ta>tb The problem is that each of the clocks can only display ONE TIME. They CANNOT display multiple times. At most, only one of the three results listed above can be true, and therefore, at least two of the results have to be false. Because of this, Special Relativity cannot be valid, and there must therefore be one or more preferred reference frames. If someone has a answer to the triplet paradox that is consistent with SR, please share.