sentence2_structure: objects<>are<>atomic/subatomic$$$The specialized study of the motion of objects<>is called<>quantum mechanics
sentence1: Finally we will consider various topics in modern physics including special relativity, quantum mechanics, radioactivity and subatomic physics.
sentence2: The specialized study of the motion of objects that are atomic/subatomic in size is called quantum mechanics.
question: The specialized study of the motion of objects that are atomic/subatomic in size is called what?