Von Neumann machine

In view of the success of von Neumann s machine-based hydrodynamics in 1944, and at about the time when the fission bomb was ready, some scientists at Los Alamos were already thinking hard about the possible design of a fusion bomb. Von Neumann invited two of them, Nicholas Metropolis and Stanley Frankel, to try to model the immensely complicated issue of how jets from a fission device might initiate thermonuclear reactions in an adjacent body of deuterium. Metropolis linked... 

Von Neumann was able to construct a self-reproducing UTM embedded within a 29-state/5-cell neighborhood two-dimensional cellular automaton, composed of several tens of thousands of cells. It was, to say the least, an enormously complex machine . Its set of 29 states consist largely of various logical building blocks (AND and OR gates, for example), several types of transmission lines, data encoders and recorders, clocks, etc. Von Neumann was unfortunately unable to finish the proof that his machine was a UTM before his death, but the proof was later completed and published by Arthur Burks [vonN66]. 

Von Neumann s machine is actually an example of a universal constructor. It must not only carry out logical operations (i.e. act as a universal computer), but must also be able to identify and manipulate various components. The universal constructor C must be able to both (1) construct the machine whose blueprint appears in symbolic form on its input tape and (2) attach a copy of that same blueprint to the machine once it is constructed. Self-reproduction is the special case where C s input tape actually contains the blueprint data for C itself. Alas, there are a few subtleties. 

Von Neumann recognized this problem, of course. His solution was to essentially use the cooperative action of several automata to effectively copy a machine s blueprint. He first introduced a copier automaton M that copies whatever blueprint B it is given. Next, he defined an automaton A" that inserts a copy of B into the... 

Recall our outline of the von Neumann construction, and the subtlety involved in eliminating what at first sight appears to be an inevitable infinite regress. The subtlety arises essentially because we are forced to think of our blueprint data as both (i) consisting of active instructions that must be executed and (ii) as an assemblage of passive information that is merely a part of the overall structure that must be copied and attached to the offspring machine. 

The mathematician John von Neumann was one of the pioneers in AL he developed an analogy between the functions of a living organism and those of a machine. The latter consisted of two important parts which, when the computer industry developed, were referred to as software and hardware. Hardware processes information, while software embodies information (Dyson, 1985). 

What matters is that the genotype - the biological software - is a deposit of instructions and therefore is potentially capable of carrying the project of embryonic development. This was the long-awaited answer to vitalism, and the computer became therefore the new model of mechanism. In reality, the new model of a living machine is not the computer that we encounter in our daily life, but an ideal machine known as von Neumann s self-replicating automaton. 

Neural nets are computing programs that behave externally as multi-input multi-output computing blocks. Although artificial neural networks were initially devised for parallel processing, they are being used on sequential machines (von Neumann) as well. 

The multicomputer model inherits the Eckert-von Neumann model for each node in the machine. This has the important practical consequence that standard languages like Fortran, C and can be used if there is also a software library available to help with communication issues. This combination of a standard language and communication library is called the message passing model. 

After the war the ENIAC group dispersed in November of 1945 von Neumann was named Director of an Electronic Computer Project at the Institute for Advanced Study, Princeton. The purpose of this project in the words of its Director was to develop and construct a fully automatic, digital, all-purpose electronic calculating machine... which if intelligently used, will completely revolutionize our computing techniques, or to formulate it more broadly, the field of approximation mathematics (/5). Following the ENIAC dedication the next February, Goldstine and Burks joined the IAS Project. Eckert and Mauchly subsequently left the Moore School to establish their own company, the Electronic Control Company, which later became the Eckert Mauchly Computer Corporation and, ultimately, the UNIVAC division of Sperry Rand. 

Burks, Goldstine, and von Neumann first identified the principal components of the general-purpose computer as the arithmetic, memory, control, and input-output organs, and then proceeded to formulate the structure and essential characteristics of each unit for the IAS machine. Alternatives were considered and the rationale behind the choice selected presented. Adoption of the binary, rather than decimal, number system was justified by its simplicity and speed in elementary arithmetic operations, its applicability to logical instructions, and the inherent binary nature of electronie components. Built-in floating-point hardware was ruled out, for the prototype at least, as a waste of the critical memory resource, and because of the increased complexity of the circuitry consideration was given to software implementation of such a facility. 

Grubmueller, H. (2004). Proteins as molecular machines Force probe simulations published in Computational soft matter From synthetic polymers to proteins, lecture notes. In N. Attig, K. Binder, H. Grubmueller 8c K. Kremer (Eds.), NIC series (Vol. 23, pp. 401-422). Julich John von Neumann Institute for Computing. ISBN 3-00-012641-4. 

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