22 questions · 15 almanac · 0 findings

Special Relativity

Einstein's theory of space and time at constant velocity.

Almanac Time and Space Stop Being Fixed
  • What two postulates did Einstein start from in deriving special relativity?
  • What happens to time, length, and simultaneity for an observer in motion under special relativity?
  • Why do GPS satellites need to correct for the effects Einstein predicted in this paper?
Almanac Three Pages Bind Mass to Energy
  • What relationship between mass and energy did Einstein establish in his September 1905 paper?
  • Why does even a small amount of mass correspond to such a large quantity of energy?
Almanac The Ether That Wasn't There
  • What was the luminiferous ether supposed to explain, and why did physicists believe light needed one?
  • How did Michelson and Morley's interferometer attempt to detect Earth's motion through the ether?
  • Why did a null result unsettle classical physics for nearly two decades before Einstein resolved it?
  • What instruments did Michelson refine to make his light-speed measurements so precise?
Almanac Two Small Clouds, One Wrong Forecast
  • What were the two 'clouds' Kelvin identified in his 1900 lecture as physics' remaining unsolved problems?
  • How did the two clouds Kelvin described end up resolving into quantum mechanics and relativity?
Almanac A Sky That Rains Invisibly
  • How do cosmic-ray-produced muons reaching sea level serve as experimental proof of time dilation?