Who is Alan Turing?

Alan Mathison Turing (born 23 June 1912 – died 7 June 1954) was an English mathematician, computer scientist and cryptologist. He is considered the founder of computer science. With the Turing test he developed, he put forward a criterion for whether machines and computers can have the ability to think.

II. He was considered a war hero because he played a crucial role in cracking German codes during World War II. In addition, during his years at Manchester University, he laid the conceptual basis of modern computers with the definition of an algorithm called the Turing machine.

His name also went down in the history of mathematics with the Church-Turing Hypothesis he developed with his thesis teacher Alonzo Church, whom he worked with at Princeton. This thesis states that all calculations that can be described by an algorithm consist of calculations that can be described by four operations, projection, articulation and scanning operations. It is an undisproved hypothesis about the philosophy of mathematics rather than a mathematical theorem.

In 1952, Turing, who applied to the police with the complaint that he was blackmailed and declared that he was gay, was tried on the charge of homosexuality and sentenced to be shot with estrogen injection, which was used as a chemical castration method for 1 year. He died in 1954 from potassium cyanide poisoning. The police investigation determined that Turing died as a result of suicide by taking cyanide poison with the apple he ate. However, it has been argued that Turing's poisoning was not due to suicide by himself and that others had a hand in this suspicious death.

He became a part of the academic informatics world with the Turing Award, which is named after him and is considered the Nobel of computer science.

The reaction-diffusion model, one of the most important mathematical models in developmental biology, was also formulated by Turing.

Childhood and youth

His mother, Sara, became pregnant in the town of Chatrapur, Orissa, India. His father, Julius Mathison Turing, was an Indian civil servant in the British Indian colonial administration. Julius and his mother Sara wanted to be born in England, so they came to London and settled in a house in Maide Vale (now the Colonnade Hotel) where Alan Turing was born on June 23, 1912. He had an older brother named John. His father was in the Indian Civil Service business, and during Turing's childhood the family traveled between Guildford, England and India, leaving their two sons to stay with friends in Hastings, England. Turing showed signs of genius early in life and displayed them consistently.

His parents enrolled him at St Michaels, a day school, when he was 6 years old. His other instructors, and then the headmaster of the school, quickly recognized his intelligence. In 1926, at the age of 14, he entered the Sherborne School, a famous very expensive private school in Dorset. The first day of the school term coincided with the General Strike in England; however, Turing was so enthusiastic about his school that he cycled alone, more than 60 miles from Southhampton, to school that day when trains didn't run in the country, and spent the night in a hotel halfway through.

Turing's natural disposition towards mathematics and science did not earn him the respect of his teachers, whose definition of education at Sherborne focused more on classical Ancient Greek and Latin. The Principal of the School wrote to his family: “I hope he does not remain ignorant between the two schools. If he is going to stay in a private school, he must accept the special education of the private school; If he's just going to be a devoted scientist, he's wasting his time in this private school.”

Despite this, Turing continued to demonstrate his outstanding talent in the studies he loved, solving problems in advanced higher mathematics even before he learned the derivative and integration topics in his classes. At the age of 1928 in 16, he encountered the work of Albert Einstein; not only grasped it; he uncovered this by studying Einstein's critiques of Newton's claims of motion (without using textbook texts that did not explain them).

Turing formed a close friendship and romance with Christopher Morcom, a slightly older academic student at school. Morcom died just weeks after the end of his last semester at Sherborne, of tuberculosis, which he contracted as a child from drinking tuberculent cow's milk. Turing's religious faith was destroyed and he became an atheist. He embraced the belief that all world phenomena, including the working of the human brain, are materialistic.

University and his work on computability

Turing's unwillingness to study classical Greek and Latin, and his always preferred mathematics and science, prevented him from winning a scholarship to Trinity College, Cambridge. He went to Cambridge Kings College, his second choice. He was a student there from 1931 to 1934, earned a diploma with a distinguished honor, and was elected an academic member of Kings College in 1935 for a dissertation on the central limit theorem.

In a very important article, Computable Numbers: An Application to the Problem of Decision Making, presented on May 28, 1936, Kurt Gödel reformulated the results of proofs of limits of computation and proof prepared in 1931 with the universal arithmetic-based formal language, replacing it now as Turing machines He put forward the proof that we have mentioned, based on simpler and more formal methods. He proved that any mathematical problem imaginable can be solved using such a machine, if it can be represented by an algorithm.

Turing machines are the main research element of today's theories of computation. He went on to prove that the Termination Problem for Turing machines is undecidable, and that it is not a consequence of the Decision-Making Problem: in general, it is not possible to decide, even if an algorithmically presented Turing machine always terminates. Although his proof was published later than Alonzo Church's equivalent proof of the Turing result based on lambda computation theory, Turing's work was much more acceptable and intuitive. A new side to his theory was the concept of the "Universal (Turing) Machine", the idea of ​​a machine that would do the tasks of any other machine. The article also introduced the concept of identifiable numbers.

From September 1936 to July 1938 he spent almost continuously working alongside Alonzo Church at the Institute for Advanced Studies at Princeton University. Besides abstract mathematics, he also worked on cryptology, and also completed three stages of a four-stage electro-mechanical binary multiplication machine. He submitted his thesis in June 1938 and earned the title of Doctor of Philosophy from Princeton. In his scientific thesis, he examined the concept of computation with Turing machines associated with divination machines, enabling him to investigate problems that a Turing machine cannot solve.

Returning to Cambridge, England, he attended Ludwig Wittgenstein's lectures on the foundations of mathematics. The two of them had arguments among themselves and could not get along. Turing advocated formalism, and Wittgenstein claimed that mathematics invented new facts rather than rediscovered them. He also worked part-time at the Government Code and Cipher School (GCCS).

Turing-Welchman "bombe" machine

A few weeks after joining Bletchley Park, Turing designed an electromechanical machine that would help break Enigma fast; The name Bombe was given to this machine, in reference to the Bombe name given to the device that was previously developed from Polish designed machines in 1932. With additions by the mathematician Gordon Welchman's suggestions, Bombe Enigma was used as the most important and only fully automated code cracking machine in attacking protected message traffic.

Professor Jack Good, who was working on cryptanalysis at Bletchley Park at the same time as Turing, later honored Turing with these words: “Turing's most important contribution, in my opinion, is the design of the cryptanalytic machine Bombe. It was based on a logical theorem that seemed absurd to the untrained ear, or even the contradictory idea that we could possibly understand everything.”

Bombe explored possible correct settings to use in an Enigma machine message (eg cog commands, cog settings, etc.) and used it for testing that found a suitable and reasonable piece of plaintext. For the wheels, there were 1019 possible states for general three-wheel Enigma machines and 4 possible states for 1022-wheel submarine Enigma machines. Bombe exhibited a series of logical conclusions based on the crib, which were completed electrically. Bombe detected when a conflict appeared and eliminated edits by moving it to the next. Many of the possible arrangements were inconsistent and the rest were discarded, leaving a few for details to be explored. Turing's Bombe was first installed on March 18, 1940. By the end of the war, there were over two hundred Bombes in operation.

The first computers and the Turing test

He was at the National Physics Laboratory where he worked on the ACE (Automatic Computer Engine) design from 1945 to 1947. On February 19, 1946, he presented the article on the detailed design of the first program-memory computer. Although the ACE was a viable design, the secrecy surrounding the wartime work at Bletchley Park led to delays in project start-up and made it unimaginable. In late 1947, after six years of continuous study, he returned to Cambridge to work as he pleased in a field of his choice. While he was at Cambridge, during his absence Pilot ACE was done. Its first program was held on May 10, 1950.

In 1948 he was appointed Lecturer to the Mathematics Department in Manchester. In 1949 he became deputy director of the computer lab at the University of Manchester and worked on the Manchester Mark 1 software for one of the first real computers. During this time he continued to do more abstract work, and in 'Computer Mechanism and Intelligence' (Mind, October 1950) Turing pointed to artificial intelligence and advanced an experiment now known as the Turing test, an attempt to set the standard for a machine to be called 'intelligent'. it took. His claim was that thinking for a computer was possible if it could deceive the questioner that he or she is a human being in dialogue.

In 1948, Turing began writing a chess program for a computer that didn't exist yet while working with fellow graduate student DG Champernowne. In 1952, powering up a computer enough to execute the program, he played a game in which he emulated the Turing computer, each move taking about half an hour. The game was recorded, even though Champernowne is said to have won the game against his wife, the program lost to Turing's colleague Alick Glennie.

Sample formatting and mathematical biology

Turing studied mathematical biology, particularly morphogenesis, from 1952 until his death in 1954. In 1952 he wrote a paper called 'The Chemical Basis of Morphogenesis', postulating the Turing sample shaping hypothesis. The focus of interest in this area is to understand the existence of Fibonacci numbers in the structure of living things, and the Fibonacci phyllotaxis. The example used the reaction-diffusion equation, which is now central to the shaping field. His last articles were not published until the publication of AM Turing's Compilation Studies in 1992.

Conviction of obscene indecency

Homosexuality was illegal in the UK and was considered a mental illness, but was classified as a criminal offense. In January 1952, Turing met a 19-year-old, Alan Murray, at a movie theater, and Alan Murray went to Turing's house several times to stay with him. A few weeks later, Alan Murray went with an acquaintance to rob Turing's house. Turing reported this theft to the police. The police caught the thieves and during the investigation the fact that Alan Murray had a homosexual relationship with Turing came to light. Turing admitted that it was true, too. Turing and Murray were charged with obscene impropriety and taken to court under Section 1885 of the 11 Penal Code Supplement. Turing was unrepentant and was convicted of the same crime as Oscar Wilde 50 years earlier.

Turing was presented with a choice between conviction and, depending on his condition, probation on his ongoing hormonal treatment to reduce his libido. To escape prison, he accepted injections of the hormone estrogen, which would castrate him within a year. As he was found guilty, his credibility clearance for government secret affairs was revoked, and his ongoing consultation on cryptographic issues at the then top secret GCHQ was also terminated. At that time, the British government was dealing with the problem of the Cambridge Five, a group of agents (Guy Burgesss and Donald Maclean), most of whom had agreed to spy for the Soviet Union during their academic studies at Oxford-Cambridge and had subsequently held the highest ranks in the British intelligentsia. There was concern that spies and Soviet agents might entrap homosexuals in high positions. Turing had held top positions at Bletchley Park, which was top secret even after all these years, and was convicted of being homosexual.

On June 8, 1954, his housekeeper found him dead in his Manchester home. It was announced that he had died of cyanide poisoning the day before, after eating the half-eaten cyanide-poisoned apple he had left by his bed. For some reason, the apple itself was never tested for cyanide poison. Despite the claim that the cause of death was cyanide poisoning, no post-mortem was made for his body.

In these circumstances, the death of Turing, a person who served in very important positions for the top secret affairs of the state and died in a suspicious manner, led to the belief that the death of Turing was deliberate, even an assassination by the British MI5 (secret intelligence) service and was given the appearance of suicide. His mother, on the other hand, has repeatedly claimed that the poison was accidentally transmitted to the apple she was eating, due to her son's careless storage and use of laboratory pharmaceuticals. Some people believe that Turing committed suicide by pretending to be Snow White. Others point out that although Turing lost his official credibility, his passport was not taken and after this provision (although not accepted by the USA) he was allowed to go to Europe several times for academic reasons. It is known that the probability of an assassination on Turing during these visits is very high. Despite this, the British authorities find it deliberate that they turn a blind eye to these visits and the high probability of assassination. Turing's biographer, Andrew Hodges, argues that Turing's suicide in this way was to give his mother some reasonable denial.

Commemoration after death

Since 1966, the Turing Prize has been awarded annually by the Computer Mechanisms Association to a person who has written technical articles for the computer community. This award is today accepted as the Nobel Prize of the computer world.

A blue plaque has been placed on each of the buildings in front of Turing's birthplace in London (now the Colonnade Hotel) and in front of his house in Manchester, where he lived and died, to indicate that important historical figures in England lived there.

On June 23, 2001, the inauguration ceremony for a bronze statue of Turing was held at Sackville Park, located between the university buildings on Whitworth Street in Manchester. On 28 October 2004, a bronze sculpture by the sculptor “John W. Mills” was inaugurated at the “University of Surrey” campus in Guildford, Southern England. In Beltchley Park, where Turing worked, another 1,5-ton statue of Turing, made by sculptor Stephen Kettle from thin slate stones from Wales, was unveiled on 19 June 2007 with a ceremony.

Various events are held in England and in various parts of the world, especially in universities, with the aim of perpetuating the memory of Turing, and special halls, buildings and squares in faculties and campuses are called Turing. For example, a scientific symposium with international participation called 'Turing Days' is organized every year at Istanbul Bilgi University. The aim of the meeting is to create a platform where new trends and developments in 'Computation Theory and Computer Science' are discussed and introduced in international circles.

On September 10, 2009, 50 years after Alan Turing's death, British prime minister Gordon Brown admitted that what was done to the famous mathematician was appalling. And in 2013, Queen Elizabeth II granted Turing a royal pardon following his death, honoring his unique achievements.