Atomic physics is a science that studies the structure and properties of atoms and the interaction between atoms and electromagnetic radiation and other atoms.
Particle physics is a branch of physics, which studies the basic particles that make up matter and rays and their interactions.
2. The antimatter that comes into contact with the most is positrons and antineutrinos (which will be mentioned by nuclear physics majors), but what you said is too general. Generally, universities don't set up special majors to study antimatter ... you will know that antimatter and antimatter are closely related. If you have to say, both particle physics and nuclear physics majors in theoretical physics will involve ... If you choose these directions for graduate study, you will be more inclined to these studies.
3. Actually, I can learn a little in high school, but only in the field of popular science (laughs). I really know something. I just have a foundation, at least the undergraduate level of this major.