It's a great pleasure and an honor to be here as a speaker in memorial for a scientist that I have respected and admired as much as Professor Nishina. To come to Japan and talk about computers is like giving a sermon to Buddha. But I have been thinking about computers and this is the only subject I could think of when invited to talk.
The first thing I would like to say is what I am not going to talk about. I want to talk about the future of computing machines. But the most important possible developments in the future are things that I will not speak about. For example, there is a great deal of work to try to develop smarter machines, machines which have a better relationship with humans so that input and output can be made with less effort than the complex programming that's necessary today [Remember, Feynman is talking in 1985!]. This often goes under the name of artificial intelligence, but I don't like that name. Perhaps the unintelligent machines can do even better than the intelligent ones.
Another problem is that standardization of programming languages. There are too many languages today, and it would be a good idea to choose just one [It's of interest that he mentions this particular problem in his speech during a time when the computer industry was still in its earliest commercial stages and consumer use wasn't quite yet widespread. Currently, there are literally thousands of languages, with an average of about two major developments a year that garner the support of fairly large communities. Most modern languages in use today were invented (or evolved from others) within the last two decades (Java, Python, and PHP are some examples).]. (I hesitate to mention that in Japan, for what will happen will be that there will simply be more standard languages--you already have four ways of writing now, and attempts to standardize anything here results apparently in more standards and not fewer!)
Another interesting future problem that is worth working on but I will not talk about is automatic debugging programs. Debugging means fixing errors in a program or in a machine, and it is surprisingly difficult to debug programs as they get more complicated.
Another direction of improvement is to make physical machines three dimensional instead of all on a surface of a chip. That can be done in stages instead of all at once--you can have several layers and then add many more layers as time goes on. Another important device would be one that could automatically detect defective elements on a chip; then the chip would automatically rewire itself so as to avoid the defective elements [Intel and probably AMD (maybe Transmeta, too?) each have patents on self-healing chips. Nothing has come of these even yet!]. At the present time, when we try to make big chips there are often flaws or bad spots on the chips, and we throw the whole chip away. If we could make it so that we could use the part of the chip that was effective, it would be much more efficient. [This statement is fascinating, because Feynman essentially predicted in 1985 one of the most profitable tricks used by both AMD and Intel in today's market. Currently, processors that fail specific tests either in L1/L2 cache or in one or more cores are sold as lesser chips. Current generation Celerons are Core 2 Duos that didn't make the grade. Likewise, AMD's Athlon II X3s (3 cores per die) are, I believe, Athlon II X4s with one core disabled. Some Phenom IIs are also dual or quad core chips with one or more cores disabled.] I mention these things to try to tell you that I am aware of what the real problems are for future machines. But what I want to talk about is simple, just some small technical, physically good things that can be done in principle according to the physical laws. In other words, I would like to discuss the machinery and not the way we use the machines.
I will talk about some technical possibilities for making machines. There will be three topics. One is parallel processing machines, which is something of the very near future, almost present, that is being developed now. Further in the future is the question of the energy consumption of the machines, which seems at the moment to be a limitation, but really isn't. Finally I will talk about the size. It is always better to make the machines smaller, and the question is, how much smaller is it still possible, in principle, to make machines according to the laws of Nature? I will not discuss which and what of these things will actually appear in the future. That depends on economic problems and social problems and I am not going to try to guess at those.
Other issues have since been sort of resolved or pushed back. Debugging is still an issue, but as IDEs have progressed, it's become a bit easier (especially with tracing issues). Likewise, Intel and AMD both have 45nm plants and are progressing down to ~32 nanometers!
I'll be posting a little bit more of Feynman's talks on this subject. They're very lengthy, but worthwhile--particularly the bit about parallelism. You might even recognize many of the problems as still pertinent today.
