Collocations for theory - noun

complete | partial | general
Einstein''s general theory of relativity

coherent | unified
the existence of a grand unified theory that determines everything in the universe

current, new | classical
the classical theory of gravity

pet
One of her pet theories is that people who restrict their calorie intake live longer.

conflicting | critical | abstract
His comments are just abstract theory and show little understanding of the realities of the situation.

economic, legal, linguistic, literary, political, scientific, social, etc. | post-modernist, structuralist, etc.
Current feminist theory consists of several different trends.

conspiracy
a conspiracy theory about the princess''s death

chaos, game, quantum, number, particle, probability, relativity, etc.

set
Each school has its own set of theories.

have, hold | advance, develop, formulate, produce, propose | work on
Police are working on the theory that the murderer was known to the family.

refute | confirm, prove | disprove | challenge, test

evolve | hold sth, suggest sth

in ~
In theory, these machines should last for ten years.

~ about
He has a theory about why dogs walk round in circles before going to sleep.

theory and practice
the distinction/relationship between theory and practice