A theorist is someone who comes up with ideas or theories to explain how something works or why something happens, usually based on observations or evidence. Full definition
The headline is misleading and throws fuel on the fire for conspiracy theorists who won't notice or understand that it's a metaphor. (religion.blogs.cnn.com)
That is the reverse of the conventional approach imagined by theorists of education and innovation. (dotearth.blogs.nytimes.com)
The only way out, theorists at the meeting decided, was to break another supposedly fundamental law of nature — the conservation of energy. (newscientist.com)