atomic physics vs atomic theory

atomic physics and atomic theory both are nouns.

Word	Noun	Adjective	Verb	Adverb
atomic physics	Yes	No	No	No
atomic theory	Yes	No	No	No

atomic physics (noun)	atomic theory (noun)
the branch of physics that studies the internal structure of atomic nuclei	(chemistry) any theory in which all matter is composed of tiny discrete finite indivisible indestructible particles
	a theory of the structure of the atom