Quantum Chromodynamics (QCD) is one of the most successful theories in modern physics to explain the binding of nucleons inside a nucleus . But why is it so hard? In this video, I explain the difficulty of QCD by building intuition step by step—starting from the familiar idea of the strong nuclear force at the high school level, moving through Yukawa theory, and finally reaching the deeper structure of QCD. You will understand: • Why the nuclear force was first modeled using Yukawa theory • How

Gluons are the sticky particles that carry the Strong Nuclear Force. They are the "glue" of the universe. But here is a strange prediction from Quantum Chromodynamics (QCD): Since gluons interact with themselves, it should be possible for them to stick together without any quarks involved at all. These hypothetical particles are called Glueballs. A glueball is a ghost particle made entirely of force. It has no matter (quarks) inside it. It is literally a ball of pure binding energy holding itsel