Massive particle
= Massive particle
A <particle> with strictly positive <rest mass>. Its relativistic <energy> obeys $E^2=p^2c^2+m^2c^4$, and its speed in an inertial frame is below the <speed of light>.
= Massive particle
A <particle> with strictly positive <rest mass>. Its relativistic <energy> obeys $E^2=p^2c^2+m^2c^4$, and its speed in an inertial frame is below the <speed of light>.