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https://en.wikipedia.org/wiki/Universal_Turing_machine

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Every Turing machine computes a certain fixed partial computable function from the input strings over its alphabet. In that sense it behaves like a computer with a fixed program. However, we can encode the action table of any Turing machine in a string. Thus we can construct a Turing machine that expects on its tape a string describing an action table followed by a string describing the input tape, and computes the tape that the encoded Turing machine would have computed. Turing described such a construction in complete detail in his 1936 paper: “It is possible to invent a single machine which can be used to compute any computable sequence. If this machine U is supplied with a tape on the beginning of which is written the S.D [“standard description” of an action table] of some computing machine M, then U will compute the same sequence as M.”[3] Stored-program computer Davis makes a persuasive argument that Turing’s conception of what is now known as “the stored-program computer”, of placing the “action table”—the instructions for the machine—in the same “memory” as the input data, strongly influenced John von Neumann’s conception of the first American discrete-symbol (as opposed to analog) computer—the EDVAC. Davis quotes Time magazine to this effect, that “everyone who taps at a keyboard… is working on an incarnation of a Turing machine,” and that “John von Neumann [built] on the work of Alan Turing” (Davis 2000:193 quoting Time magazine of 29 March 1999). “}}

https://en.wikipedia.org/wiki/Kurt_G%C3%B6del

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Incompleteness theorem Kurt Gödel’s achievement in modern logic is singular and monumental—indeed it is more than a monument, it is a landmark which will remain visible far in space and time. … The subject of logic has certainly completely changed its nature and possibilities with Gödel’s achievement. — John von Neumann[17] … In hindsight, the basic idea at the heart of the incompleteness theorem is rather simple. Gödel essentially constructed a formula that claims that it is unprovable in a given formal system. If it were provable, it would be false. Thus there will always be at least one true but unprovable statement. That is, for any computably enumerable set of axioms for arithmetic (that is, a set that can in principle be printed out by an idealized computer with unlimited resources), there is a formula that is true of arithmetic, but which is not provable in that system. To make this precise, however, Gödel needed to produce a method to encode (as natural numbers) statements, proofs, and the concept of provability; he did this using a process known as Gödel numbering…..Gödel suffered periods of mental instability and illness. Following the assassination of his close friend Moritz Schlick,[35] Gödel developed an obsessive fear of being poisoned, and would eat only food prepared by his wife Adele. Adele was hospitalized beginning in late 1977, and in her absence Gödel refused to eat;[36] he weighed 29 kilograms (65 lb) when he died of “malnutrition and inanition caused by personality disturbance” in Princeton Hospital on January 14, 1978[37] He was buried in Princeton Cemetery. Adele died in 1981.[38]
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https://en.wikipedia.org/wiki/First_Draft_of_a_Report_on_the_EDVAC
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Von Neumann describes a detailed design of a “very high speed automatic digital computing system.” He divides it into six major subdivisions: a central arithmetic part, CA, a central control part, CC, memory, M, input, I, output, O, and (slow) external memory, R, such as punched cards, Teletype tape, or magnetic wire or steel tape. The CA will perform addition, subtraction, multiplication, division and square root. …Von Neumann’s design is built up using what he call “E elements,” which are based on the biological neuron as model,[1][2] but are digital devices which he says can be constructed using one or two vacuum tubes. In modern terms his simplest E element is a two-input AND gate with one input inverted (the inhibit input). …The treatment of the preliminary report as a publication (in the legal sense) was the source of bitter acrimony between factions of the EDVAC design team for two reasons.[3] First, publication amounted to a public disclosure that prevented the EDVAC from being patented; second, some on the EDVAC design team contended that the
stored-program concept had evolved out of meetings at the University of Pennsylvania’s Moore School of Electrical Engineering predating von Neumann’s activity as a consultant there, and that much of the work represented in the First Draft was no more than a translation of the discussed concepts into the language of formal logic in which von Neumann was fluent. Hence, failure of von Neumann and Goldstine to list others as authors on the First Draft led credit to be attributed to von Neumann alone. (See Matthew effect and Stigler’s law.) “}}

https://en.wikipedia.org/wiki/Harvard_Mark_III

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The Harvard Mark III, also known as ADEC (for Aiken Dahlgren Electronic Calculator) was an early computer that was partially electronic and partially electromechanical.
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