May 6, 2012

Reading the book Turing's Cathedral

I'm currently reading the book Turing's Cathedral by George Dyson.  Review here  It's a very heavy in detail book.  Extremely heavy and much of it goes over my head. But very interesting at the same time.  It details the development of the worlds most constructive devices: the first modern digital computer, and the world's most destructive forces:  the hydrogen bomb.  Both were fueled at the same time.

John von Neumann was the brilliant mathematician that was behind both projects. I've cut and pasted in the rest of the piece from the Google+ post on the subject.

The output of this machine was about equivalent to the modern day desk calculator. With much power to fuel the vacuum tubes and to run the refrigeration units to cool the unit so that it would run stably.
At the same time as this project was going at the Institute for Advanced Studies in Princeton New Jersey, there was another project ongoing in England with Alan Turning. Turning got ideas from von Neumann's implementation while von Neumann got ideas from Turing's design. A third project was also ongoing at MIT in the same time frame (mid to late 1940's) Project Whirlwind for air defense. This project is one that I find personally quite interesting as my dad was attending MIT in 1953/54 for a mechanical engineering master's degree. He didn't have any need (nor permission) to use this computer but the fellow he shared a house with did use it. This man was studying for his PhD in aeronautical engineering. So, he'd write out equations on a strip of brown paper and then have to translate that into machine code so that the computer could compute it. I just find it hard to believe how complicated this must have been for them!

The computer that von Neumann was building was comprised of four "organs": input/output, arithmetic, memory and control. The choice of memory drove the design yet was the last element to be resolved.

"Once the form of the high speed memory has been decided most of the other components of an electronic computer become semi-invariant" This was written by Booth and Britten, two early mathematicians that then broke away from von Neumann's team.

Von Neumann and his team of mathematicians were faced with the patent question. It is to his very very high credit that he forsaw the immense impact that this machine would have. All technical details of the the MANIAC and its programming were placed in the public domain, and freely replicated around the world. A series of progress reports were issued that were models of clear thinking and technical detail. But von Neumann started consulting for IBM and his subsequent designs were subject to their patents.

The engineers that were at the heart of the actual building of the machine were seen as lower class by the mathematicians. And yet they played a very vital role. Von Neumann was widely applauded for his willingness to embrace all of the team as being vital components. He'd ask for once per week meetings with each member and really listen and ask very pertinent questions.

Quite fascinating book all in all. Worth the read if you value some very heavy reading.

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