Material particles that have mass and occupy physical space are commonly referred to as "matter particles" or "massive particles." These particles are distinct from massless particles, such as photons, which do not have rest mass and travel at the speed of light.
Matter particles include fundamental particles, such as electrons, quarks, and neutrinos, as well as composite particles made up of combinations of these fundamental particles, like protons and neutrons. These particles are characterized by their mass, charge, and other intrinsic properties, and they interact with other particles through various fundamental forces, such as electromagnetism, gravity, and the strong and weak nuclear forces.
The properties of matter particles, including their mass and spatial extent, are described by quantum mechanics. According to quantum mechanics, particles can exhibit both wave-like and particle-like behaviors. The spatial extent of matter particles is typically described by a probability distribution that represents the likelihood of finding the particle in a particular region of space.
It's important to note that the concept of "particle" in the context of quantum physics is different from our classical intuition of a solid, localized object. Rather, particles in quantum mechanics are understood as entities described by wavefunctions that represent the probabilities of their various properties. The specific behavior and properties of matter particles are a subject of ongoing research and study in the field of particle physics.