Is matter made-up of particles or waves?
The best minds have been pondering this for 80+ years now and not making much progress. There may be no definitive answer. All we know is in some cases you can consider matter as made up of particles, and that works out fine for some calculations. In other cases matter has wave-like properties and your basic wave equations give better answers. It’s more a philosophical problem than a practical one. We’re used to things “being” one way or another and it bothers us when there’s a realm where things are not so clear-cut.
But that’s light, not matter. AS FAR AS WE KNOW, matter is a neutron/proton core surrounded by orbiting electrons. Group enough of them together in various ways and one has matter. The proton/electron combination are called “hadron” and that “Large Hadron Collider” is supposedly built exactly to find out what means that “neutron,” “proton,” “electron,” etc. Right now, slamming them together at near light speeds, those scientists are treating all of this matter as particles. So there’s your answer . . . for now.
