Length Contraction: Does Size Change Affect Density or Radiated Energy?

[jaketodd]

Length contraction is one of the main aspects of relativity. However, I have a question: When something undergoes length contraction, does it become more dense or, is the decrease in length radiated in some way?

Thank you,

Jake

 

[bcrowell]

Length contraction is one of the main aspects of relativity. However, I have a question: When something undergoes length contraction, does it become more dense or, is the decrease in length radiated in some way?

It sounds like you're imagining length contraction as a physical change in the object. Length contraction is just a difference between measurements of the same thing made by different observers. But yes, according to an observer who sees an object as length contracted, its density would be increased.