CIS 6930.3753X Spr.'02
Readings for Part II: 
Fundamental Physical Constraints on Computation

Continue following the general advice on reading assignments from the previous readings page.

Index to the below:

The following is my own review article which I just published in this area:

Lecture 7: Physical locality, the Speed-of-light limit, and its implications:

If you want to learn some of the basic physics underlying the lightspeed limit: Some references for the point that quantum mechanics is local, and does not violate relativity! In this next paper, Hillis mentions the impact of locality on computation. Hillis is one of the inventors of the Connection Machine, one of the top lines of parallel supercomputers in the 80's and early 90's. We're getting a bit ahead of ourselves here (anticipating part VI of the course, on Physics-Based Models of Computation), but that's OK. This next paper analyzes some implications of the speed-of-light constraint on computing. This next one takes it even farther. This is a great paper. Believe it or not, there are competent physicists who are seriously investigating whether some form of faster-than-light travel might still be consistent with known physics. (This wouldn't necessarily mean it's really possible, just that we can't conclusively rule it out yet.) Most results are pessimistic, but it is interesting to see the approaches being investigated. The following article and its references are a reasonable entry point into this literature.

Lecture 8: Quantum limits on information density:

Bounds from quantum field theory: Here are Bekenstein's papers on his general bounds, which are independent of, for example, the number of particle species.  Bekenstein's bounds originally arose out of work on black-hole thermodynamics by himself and the famous Stephen Hawking. Papers on the controversy about whether black holes destroy infropy:

Lecture 9: Limits on communication bandwidth, and bandwidth density

Lecture 10: Nature of energy, limit on rate of state-change, and wrap-up.

The below readings address the limit on transition rates, but not the different types of energy, which is a new topic for this course that really needs to be moved to an earlier lecture on key thermodynamics concepts, and that I haven't collected many readings on yet.