Philip W. Anderson, an American physicist whose explorations of electronic behavior in solid materials like glass, crystals and alloys led to a Nobel Prize and deepened science’s understanding of magnetism, superconductivity and the structure of matter, died on Sunday in Princeton, N.J. He was 96.

His daughter, Susan Anderson, confirmed the death.

“Anderson was the pre-eminent condensed-matter theorist of his day — a day that lasted for over 50 years — and his fingerprints are everywhere,” Nigel Goldenfeld, a physics professor at the University of Illinois at Urbana-Champaign, said by email.

Condensed-matter, or solid-state, physics focuses on the properties of solids and liquids with high densities of atoms that constantly interact with one another; by contrast, particle physics deals with subatomic particles. Much of Dr. Anderson’s most influential work concentrated on randomly structured, or “disordered,” materials that lack the regular crystalline composition of most matter.

He was particularly interested in the behavior of electrons within these disordered materials, which include certain kinds of semiconductors. In 1958, he published a paper in which he showed how electrons in disordered materials can either move freely or become fixed in a specific position, as if stuck in glue, depending on the degree of disorder. His finding of how electrons behave when trapped, or localized, became known as Anderson localization, and was subsequently extended to the properties of light and sound waves.