Library.

“Modern physics does not treat matter as a fundamental material substance in the traditional philosophical sense.”

Contemporary quantum field theory largely replaces the classical picture of matter as self-subsisting material substance with fields, quantum states, and derivative particle excitations. However, physics does not prescribe a single settled ontology, and particle-based or other interpretations remain active. The conclusion is therefore well supported as a broad characterization, not as an exceptionless position across all modern physics.

“Antimatter is mathematically equivalent to matter with reversed time dynamics.”

The claim captures a real feature of quantum field theory but significantly oversimplifies it. The Feynman-Stueckelberg interpretation does treat antiparticles as mathematically equivalent to particles propagating backward in time, but the rigorous symmetry — the CPT theorem — requires simultaneous reversal of charge, parity, and time, not time alone. Reducing this three-part transformation to "reversed time dynamics" omits essential components and gives a materially incomplete picture of the underlying physics.