Ernest Walton is known for splitting the atom. During the early 1930s, Walton and John Cockcroft collaborated to build an apparatus that split the nuclei of atoms. This research at Cambridge in the early 1930s won Walton and Cockcroft the Nobel Prize in physics in 1951 for developing the first nuclear particle accelerator, known as the Cockcroft-Walton generator.

Ernest Walton attended Methodist College Belfast. He died in Belfast in 1995.