Thursday, September 6, 2018

Physics Q&A #6. What Is Mass?


I spend a lot of time on this blog explaining a physical spacetime model and the underlying metaphysics. In this series of posts, each entry poses a physics question for the spacetime model, along with the answer.

Physics Question #6. What is mass? For an elementary fermion (lepton or quark), mass is the inverse of the precision with which the location of a stationary particle can be known. This makes sense, because mass is defined as a measure of inertia or resistance to acceleration. Resistance to movement and having a known or fixed location are really the same thing. For a composite particle such as a baryon, mass is mostly binding energy (gluons), the masses of the elementary constituents (quarks) contributing very little to the baryon mass. For a massive gauge boson, mass is the inverse of the range of the force carried by the particle.

The masses of the elementary particles are said to be determined by the Higgs field. See this post to learn all about the Higgs and its relation to mass