Introduction to Modern Physics

Introduction to Modern Physics

1. Concepts of Special Relativity and Lorentz Transformations

   • Special theory of relativity
     • relativity connects space and time, matter and energy, electricity and magnetism – links that are crucial to our understanding of the physical universe.
   • Lorentz transformation
     • how to relate space-time coordinates of an event with an inertial reference frame of that same event with the space-time coordinates on a second inertial frame.

2. Time Dilation and Length Contraction

   • At speed of light things change, unlike objects moving at relatively low speeds , the speed of light is the same for all observers in different frames of reference.
     • this won’t happen at the speed of light.
       • as you approach the speed of light time will go slower and you will shrink, making impossible to catch up.
   • Time dilation
     • Every time that time intervals between events are compared and measured by observers in different inertial reference frames
   • Length contraction
     • every time that you want to compare the length of an object measured by observers that are in different inertial reference frames.

3. Mass-energy Relation and Basic Principles of Quantum Physics

   • The mass-energy relation states that mass can be converted to energy and energy to mass.
   • Quantum theory, waves and particles
     • Electromagnetic radiation has a dual character in its interaction with mass, since there are cases in which it exhibits wave properties (as on diffraction) and in other cases as on the photoelectric effect, where it behaves as particles,
       • Black body radiation
         • if you keep heating a body the amount of energy it absorbs and emits can go to infinity and will make the body to radiate ultraviolet light.