SPECIAL THEORY

• Special Theory of Relativity


  • 1905
  • Deals with motion in the absence of gravity
  • Describes the relationship between space and time in inertial frames (constant velocity, no acceleration)
  • Observation of events from different viewpoints
• Reference point


  Fixed points or objects
• Frame of reference 


  The view point
• Consistent Law Principle

  • All motions are relative to the chosen reference frame
  • The laws of physics are the same in all frames of reference that are moving at a constant velocity with respect to one another
• Constancy of Speed


  • The speed of light in empty space has the same magnitude for all observers regardless of their velocity
• Consequences

  • An object's length shortens while moving
  • Clocks run slowly while moving and;
  • The mass of objects increases while moving
  • Time dilation - moving clocks run slower
  • Length contraction - moving objects appear shorter
  • Relativity of Simultaneity - events that are simultaneous in one frame may not be in another
  • Mass-Energy Equivalence - Energy and mass are interchangeable ( E = mc² )