Physics is the field of science that explores the axioms of reality. It is the search for truths that apply universally to everything that we encounter, regardless of size or intelligence.
By implication, every event that we experience must be consistent with the laws of physics. An important supposition is implied here: if the laws we know today are to hold tomorrow, the basic laws of reality must be stable over time. At some level, life itself is proof of that: it's evolution over billions of years would have been disrupted if the basic laws changed significantly.
The underpinnings of our understanding of the universe are relativity and quantum mechanics, and their amalgamation: quantum field theory. Their mathematical formulations are organized around a small set of fundamental principles. In the case of quantum field theory and general relativity, the mathematical implications of those principles are enormously complex. The power and beauty of these theories is precisely in the consequence that simple principles can be used to explain phenomena of wonderful diversity.