string theory vs particle physics

string theory and particle physics both are nouns.

Word	Noun	Adjective	Verb	Adverb
string theory	Yes	No	No	No
particle physics	Yes	No	No	No

string theory (noun)	particle physics (noun)
(particle physics) a theory that postulates that subatomic particles are one-dimensional strings	the branch of physics that studies subatomic particles and their interactions