Footnotes for The Da Vinci Code
1. Albinism is a genetic condition characterized by a lack of pigmentation in the eyes, skin and hair. Contrary to the way they're depicted in movies, albinos would not make good assassins—for one thing they always have vision problems, for another, aside from their appearance and the taunting they often have to endure, albinos are normal people. Many are legally blind and cannot see well enough to drive cars let alone accurately shoot guns. The evil albino has become yet another mindless movie cliché used for attracting attention to fictional villains.
2. The Ultimate After Action Report! The Gun Zone, 5-31-06
3. Opus Dei members will likely get a good laugh out of many things in the movie including the portrayal of the cilice. It is not a torture device and does not break the skin. the cilice creates a minor leg irritation which is intended to be a reminder of Christ's suffering. Mother Theresa sometimes wore one.
4. To determine its position, a Global Positioning System (GPS) device has to detect signals from four different satellites. Any grounded conductive material between the satellites' transmitters and GPS receiver will attenuate the signal. The degree of attenuation depends on the thickness of the material and its conductivity. Even stone and concrete will usually have enough moisture in them to be at least slightly conductive and capable of attenuating signals. Signal strength will be reduced, at least some, in almost any building. With enough signal attenuation, a GPS unit will not work reliably.
The satellites all contain atomic clocks and simultaneously broadcast the time on a repeated basis along with information about their position. Using this information and assuming the satellite signals have traveled at the speed of light, the GPS unit can calculate its distance to each satellite and fix its own position by a form of triangulation. The speed of the signal, however, is reduced significantly by traveling through any dense material. This speed change causes an error in the position calculation. Due to the reduced speed, the signal will also be refracted or bent if it strikes the surface of a dense material at an angle. The effect can substantially change the path of the signal creating yet more timing errors. Furthermore, reflections off building surfaces combined with refraction can produce multiple signals from the same source arriving at the receiver—each signal with a different time of travel. GPS devices lose accuracy inside buildings, that is if they work at all.
5. A group at University of California at Berkley is working on tiny networkable devices referred to as smart dust. While far less sophisticated than a GPS tracking device, groups of these devices can form self configuring networks and transmit data from sensors measuring parameters like temperature, pressure, etc. Such devices can be accessed via an internet connection. Their broadcast range is very limited, however, and so at least one of the devices in their self configured network has to be near a wireless access point.
Berkeley hopes to eventually reduce the dimensions of a single device to the size a grain of rice with a mass-produced price of pennies, but are years if not decades away from doing so. A commercial form of smart dust called a mote is available from Crossbow Technology, Inc. (http://www.xbow) for around $100, but its footprint is about the size of the two AA batteries required to run it. Prototypes the size of buttons (including a hearing aid type battery for power) have already been built at Berkeley. Although smart dust itself is not designed for GPS tracking, such an application is conceivable in a small but more sophisticated unit. As mentioned before, however, such a device would have limited broadcasting range and need to make nearby wireless network connections to off-load data. Such a device would also be a good deal more expensive than a similar sized smart dust unit.
6. According to http://entertainment.howstuffworks.com/davinci-code.htm restrooms in the part of the Louvre depicted in the film have neither windows nor bars of soap. They have liquid soap dispensers.
7. The Priory was actually founded in 1956 by Pierre Athanase Marie Plantard, who had been convicted of fraud and embezzlement. Plantard concocted the myths concerning the Priory along with forged documents to support them. (see The "Priory of Sion" Hoax.)