Noun

(en noun)

Someone who constructs theories, especially in the arts or sciences.

*{{quote-magazine, date=2012-01

, author=Michael Riordan , title=Tackling Infinity , volume=100, issue=1, page=86 , magazine= citation , passage=Some of the most beautiful and thus appealing physical theories, including quantum electrodynamics and quantum gravity, have been dogged for decades by infinities that erupt when theorists try to prod their calculations into new domains.}}