Quantum electrodynamics, commonly referred to as QED, is a quantum field theory of the electromagnetic force. Taking the example of the force between two electrons, the classical theory of electromagnetism would describe it as arising from the electric field produced by each electron at the position of the other.
Season 2. Season 4. Season 3 of Vikings premiered on February 19, 2015 on History in Canada and in the United States and concluded on April 23, 2015, consisting of 10 episodes. The new 10-episode season begins with...
Season 5. Season 4 of Vikings premiered on February 18, 2016 on History in Canada and in the United States and concluded on February 1, 2017. It is the final season to feature Travis Fimmel as King Ragnar. This season, consisting of 20 episodes, was split into two ten-episode parts with the first part airing from February 18 to April 21, 2016 while the second part aired from November 30, 2016 to February 1, 2017.