Hard to drive to, but if you are in Puerto Rico, this is a must. It's even bigger than that. You can pretend you are James Bond running around.

This is the latest in a very very long series of failures of optical interconnect in multiprocessors, in the computer room, and at the desktop. Since the '80s people have told us that wires will never keep working, and optics is the only solution. They have been wrong, and continue to be wrong. I was even blasted by a respected physicist that told me that there was an inherent power advantage for optics. That was wrong also. Optics is great if you need to go across the ocean, but don't tell me you want to go across the cabinet with it.

A Course in Mathematics for Students of Physics (Vols. 1&2), Paul Bamberg and Shlomo Sternberg; This is the book you will wish was used for your intro calculus text. It covers linear algebra and vector calculus done "right." Specifically, it makes the crucial distinction between vectors and one-forms, and you will be annoyed to realize you have been fooled all these years by poor instruction.

The Geometry of Physics, Theodore Frankel; An excellent introduction to differential geometry and its application not just to GR but to other areas of physics as well. Highly recommended.

A First Course in General Relativity, Bernard Schutz; I found this book helpful in some specific areas -- notably understanding the notions of the stress-energy tensor.

Gravitation, Charles Misner, Kip Thorne, & John Wheeler; This is the classic text, and is comprehensive and comprehensible. I like Wheeler's way of thinking about physics, and it shows through here. There is the standard joke, that this is a text which not only discusses gravitation, but also attempts to demonstrate it by its high mass.

You can't make vacuum devices with holes, so there are not the complementary devices needed for CMOS like operation. We would be working with a technology similar to N-channel FETs, with all the problems of low-output state power dissipation. It won't scale to high integration levels. That said, the technology probably has niche applications in high temperature and rad-hard environments.

Wire wrapped construction was a great step forward in reliability from the solder of the PDP-1 and PDP-6 computers.