The H-bomb and birth of the computer, part III: triumph of brains and slide-rules

The question that led to von Neumann’s involvement with Edvac in 1944-1945 was whether Teller’s design (the “Super”) for a hydrogen bomb was feasible. The question that von Neumann wanted to settle was whether in Teller’s design a fission explosion causes a self-sustained propagation of fusion in fusible material.

When Eniac was ready for the first trials in December 1945, von Neumann had convinced its owner, the Ballistics Research Laboratory, to give the ultra-secret computation from Los Alamos priority. Only the researchers from Los Alamos, Metropolis and Frankel, had the requisite security clearance to know the subject of the computation. The necessary personnel to help operating the Eniac did not. The problem was finessed by ruling that the equations and the data only were demoted from their lofty top-secret classification. Eniac performed splendidly, all 18,000 tubes working in unison for a sufficient proportion of time to get the computation completed in six weeks.

The H-bomb and the computer, part II: the revolution that almost didn’t happen

In spite of the tumultuous development of computers, the architecture in the form of the fetch-execute cycle has remained the same from EDVAC design of 1945 to the present day. And we are used to call this basic architecture “von Neumann machine”. This makes John von Neumann a sort of patron saint of our field.

Not everyone accords this status to the great mathematician who lived from 1903 to 1957. One of my favourite architecture books refuses [5, page 32] to use the term because of the supposedly equal contributions by J. Presper Eckert and John Mauchly. Many of those who do accord full credit to von Neumann for the architecture invoke the name in the pejorative sense of “von Neumann bottleneck” and suggest that the architecture has hindered rather than helped the development of computers.

In this essay I review publications that shed light on the origin of the computer and conclude that it was von Neumann who made the critical contributions in 1944 and 1945. In addition I will argue that von Neumann’s was the basic architecture that propelled the computer along its miraculous trajectory covering three orders of magnitude in size and five in cost and processor speed. Finally I will reflect on the fact that von Neumann was not only an extraordinary genius, but also that he combined in his background a most unusual combination of disciplines — a combination that was essential to the birth of the computer. Without this fortuitous confluence of circumstances the development of computers in the period 1950 – 2000 would not have had the explosive character that we actually experienced. Hence “The Revolution That Almost Didn’t Happen.”

The H-bomb and the birth of the computer, Part I: Edward Teller’s obsession

In 1945 the stored-program computer was invented; by 1950 every country wanted computers. None were for sale, so every country was trying to build them. Not just the big players, like the US and Britain; by 1955 computers had also been built in Switzerland, Russia, the Netherlands, Sweden, and Belgium. At the origin of this wave of enthousiasm was J. von Neumann’s prestige and advocacy. In 1945 he had not only been the first to describe how to build a computer in the modern sense, but he was also infused with the conviction that this was nothing less than a new, universal research instrument with the potential of revolutionizing science. As a result he wanted his design to become as widely known as possible, as soon as possible.

How von Neumann got involved in electronic computing will be the topic of the next instalment. Here I first want to recount why he got involved. It had to do with the unholy alliance of science and war.