Context: After the success of quantum electrodynamics, Feynman turned to quantum gravity. By analogy with the photon, which has spin 1, he investigated the consequences of a free massless spin 2 field, and derived the Einstein field equation of general relativity, but little more. The computational device that Feynman discovered then for gravity, "ghosts", which are "particles" in the interior of his diagrams that have the "wrong" connection between spin and statistics, have proved invaluable in explaining the quantum particle behavior of the Yang–Mills theories, for example, QCD and the electro-weak theory.

Question: Where did  Feynman find success before moving to quantum gravity
Answer: quantum electrodynamics

Question: What did Feynman investigate while working on quantum gravity?
Answer: consequences of a free massless spin 2 field

Question: What equation did Feyman derive?
Answer: Einstein field equation of general relativity

Question: What did Feynman's discoveries help explain?
Answer: Yang–Mills theories

Question: Which parts of the Yang-Mills theories did Feynman help explain?
Answer: QCD and the electro-weak theory

Question: Where did Feynman find failure before moving to quantum gravity?
Answer: Unanswerable

Question: What did Feynman ignore while working on quantum gravity?
Answer: Unanswerable

Question: What equation did Feynman steal?
Answer: Unanswerable

Question: What did Feynman's discoveries hurt the explanation of?
Answer: Unanswerable

Question: Which parts of the Yang-Mills theories did Feynman dispel?
Answer: Unanswerable