High Quality Content by WIKIPEDIA articles!In mathematics, Pappus's centroid theorem (also known as the Guldinus theorem, Pappus Guldinus theorem or Pappus's theorem) is either of two related theorems dealing with the surface areas and volumes of surfaces and solids of revolution. The theorem is attributed to Pappus of Alexandria and Paul Guldin.Pappus of Alexandria (Greek ) (c. 290 c. 350) was one of the last great Greek mathematicians of antiquity, known for his Synagoge or Collection (c. 340), and for Pappus's Theorem in projective geometry. Nothing is known of his life, except (from his own writings) that he had a son named Hermodorus, and was a teacher in Alexandria.