 In Europe, while Siddique was working on his post-doctoral research at the Paris University, he had the opportunity to meet with the members of ""The Paris Group"" where he had led the discussions on unsolved problems in physics and in mathematics.During his stay in Great Britain, he studied Quantum mechanics and published scientific papers at the Cavendish Laboratory.In 1931, Siddiqui then returned to Hyderabad, British Indian Empire, and joined Osmania University there as an Associate Professor of Mathematics.