Investigating Relativistic Lifetimes: A Cosmic Ray Experience

       
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So, you'd like to do an experiment . . .
We cannot always get use of an accelerator to look at high-energy, relativistic particles. Nor can we find a train, airplane, automobile, or spacehip that would move close to the speed of light. Not even a Yugo GT goes that fast. However, nature provides us--literally bombards us--with relativistic particles everyday: cosmic ray muons.

It is possible to at least plan how you can investigate relativistic lifetimes by measuring cosmic ray counts at different altitudes. To do this, it helps to answer some key questions:
  1. Do you want to show the time dilation effect on muon lifetimes quantitatively or qualitatively?

  2. What materials will you need? What materials do you have?

  3. How will you get to different altitudes? Consider your current location. Can you get somewhere high enough to make a difference?

  4. Using the equipment you have--or can make--how will you obtain a fairly accurate muon count?

  5. How will you display your data? How will you analyze it?

  6. What will you do to minimize and deal with error?

  7. How will you communicate your results?

And now for a few caveats . . . .

 The method of muon counting available to us right here may not be precise enough for our purposes; what's more, if you are in northern Illinois you will see a paucity of high mountains. Even the Sears Tower is not high enough without very precise instruments. So, do we:
  1. Give up?

  2. Find a way to overcome these problems?

  3. Plan for a longer-term experiment in a more conducive environment?