Sunok was a Vulcan scientist who, at some point, was responsible for the refinement of transporter technology that was being used by the United Federation of Planets. Prior to his contribution, transporters had only a 99.9992% accuracy in the transportation of living subjects. The introduction of Sunok of Vulcan's uncertainty physics reduced this to the point that it was virtually impossible for the equipment to malfunction except due to operator error.
In 2248 during a meeting between Starfleet Captain Christopher Pike and Spock, the latter of the two elaborated on Sunok's involvement in refining transporter technology. (TOS novel: Crisis on Vulcan)