Alan Turing was a celebrated twentieth century British mathematician. Besides being a brilliant mathematician he was an equally gifted computer scientist, theoretical biologist and logician. He is credited for his noteworthy contribution to theoretical computer science, hence, considered the father of this field.
Born on 23 June, 1912, Alan Mathison Turing was raised in Maida Vale, London, England. His father Julius Turing worked for Indian Civil Service at Chhatrapur and due to his posting in India the couple moved back and forth from Hastings, England to India a lot. During that time Turing and his brother stayed with an old retired army couple at Hastings. At a very early age he exhibited signs of a genius which became prominent with the passage of time. He received his early education from St Michael’s and his mathematical inclination was recognized by many. Later on he was enrolled at Hazelhurst Preparatory School. Subsequently, he joined Sherborne School at the age of 13 and was quite keen to attend school.
Some of the academic staff at the school did not approve of Turing’s propensity for mathematics and science as they considered classical studies to be more valuable. They even tried to discourage him from pursuing science. In fact, the headmaster wrote a letter to his parents discussing his situation that he might be wasting his time at a public school if his only interest is scientific studies. However, it did not deter Turing from studying what attracted his interest. He solved complex problems without even studying elementary calculus and he also happen to note Einstein’s question of Newton’s Law of Motion by just studying Einstein’s work which was inconspicuous on the matter.
Turing remained a student of King’s College, Cambridge from 1931 to 1934. He received an honour’s degree in mathematics in first-class. Moreover, he garnered a fellowship at King’s on the grounds of his dissertation on the central limit theorem. “On Computable Numbers, with an Application to the Entscheidungsproblem” was the title of his work published in 1936. Kurt Gödel’s work was revised by replacing the formal language based on arithmetic with simple and hypothetical language. This resulted in the creation of Turing machine. A German mathematician was originally the one who posed Entscheidungsproblem. Turing proved that his ‘universal computing machine’ could handle any mathematical problem presented in the form of an algorithm. Moreover, he came up with the proof that there is no solution to decision problem and the halting problem with the Turing machine can’t be decided.
Another mathematician Alonzo Church, shortly before the publication of Turing’s proof, published his own proof. However, Turing’s proof was more accessible as it also touched upon the concept of ‘Universal Machine’. Even John von Neumann credits Alan Turing for his input in the development of modern machines. The study of theory of computation till today highly relies upon Turing machines. Furthermore, he studied cryptology as well at Princeton University. He built three of four stages of an electro-mechanical binary multiplier during his studies. He was awarded a doctoral degree by Princeton and his dissertation Systems of Logic Based on Ordinals played a significant role in introducing the ordinal logic.
Turing died on June 7, 1954 and his body was discovered the next day. The post mortem report showed the cause of death to be cyanide poisoning and his death was ruled a suicide. One of the bizarre explanation given by the biographers is that Alan Turing was re-enacting the scene from his favorite Walt Disney animated film Snow White and the Seven Dwarfs.