How can a particle of matter be massless if the definition of matter is Anything that has mass and takes up space?

Answer 1

By definition a massless particle has no rest mass therefore it can not take up any spacial volume. I think the confusion lies with calling something that is massless, a particle. This is because as soon as we hear particle we think "object" and objects have definite mass and volume. A photon is massless and sometimes people may refer to it as a particle of light. But in fact that is sort of a misnomer being that it really isn't a particle, though it has particle-like properties. If something is massless theorists have said that the object does not interact with the Higgs field, though gravitational effects are still felt by the photon, example: gravitational lensing.

Answer 2

Particles such as photons are considered massless because they do not have rest mass, even though they can carry energy and momentum. While they do not possess rest mass, they can still exhibit particle properties and interact with matter. Thus, massless particles can exist within the framework of particle physics even though they do not conform to the traditional definition of matter.