The crossword solution for the term 'Relativity Artist' is 'Escher'. Maurits Cornelis Escher was a Dutch graphic artist who is known for his mathematically inspired woodcuts, lithographs, and mezzotints. He is particularly famous for his works that explore the concept of relativity, such as his iconic work 'Relativity'. Escher's works have been widely celebrated for their technical mastery and unique visual style.