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How Special Relativity Works


SR deals with contractions and dilations that are not in agreement with our commonsense views of the universe. In fact, they almost appear ludicrous. Yet, there have been several observations that agree with the predictions of SR. So, until the theory is proved wrong or a simpler theory produces the same results, SR will maintain its position as the best theory out there.

Here are five concepts you have discovered in this article:

  • There is no such thing as an absolute (completely stationary) frame of reference.
  • The laws of physics apply equally to all frames of reference.
  • The speed of light is constant in all frames of reference.
  • There is no simultaneity of events between separate frames of reference.
  • You are never too old to learn.

As you pursue a better understanding of SR, Do Not fall prey to these errant statements:

  • Time slows as speed increases. (Only when viewed by another frame of reference)
  • Objects shorten as speed increases. (Same as above)
  • SR can't handle acceleration. (Biggest misconception about SR)
  • Mass increases with speed. (Energy increases, not the rest mass)
  • Nothing can travel faster than the speed of light. Crossing the speed of light barrier from either a faster or a slower speed is disallowed.

The beauty in the theory of special relativity is that it gives us laws from which we can unite space and time and also energy and mass. Special relativity is definitely a thinking person's playground.

Special thanks to John M. Zavisa for contributing this article.

  • Relativity and FTL Travel
  • An excellent book that provides an in-depth non-mathematical discussion of special relativity, general relativity and particle physics is The Dancing Wu Li Masters: An Overview of the New Physics by Gary Zukav.
  • Another excellent book that provides a more detailed analysis is Spacetime Physics : Introduction to Special Relativity by Edwin F. Taylor, and John Archibald Wheeler.