Many of the classic problems of particle physics appear in a very different light when viewed from the perspective of the multiverse. Most importantly the two great ``fine tuning'' problems that motivate the field are far less serious when one accounts for the required anthropic constraints which exist in a multiverse. However, the challenge then becomes to construct a realistic physical theory of the multiverse and test it. I describe some phenomenology of the quark and lepton masses that may provide a window to the theory that underlies the multiverse.
Book Series Title
Universe or Multiverse?
Donoghue, John, "The fine-tuning problems of particle physics and anthropic mechanisms" (2007). Physics Department Faculty Publication Series. 251.
Retrieved from https://scholarworks.umass.edu/physics_faculty_pubs/251