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November 29, 2007
My kingdom for a Zener diode
I've written before about Asimov's blind spot about hardware versus software. A related issue in more recent science fiction is the treatment of various kinds of input overload. The two cases that come most naturally to mind are:- In Haldeman's The Forever
War Mandela gets badly burned when he looks at a laser with his
image intensifiers on and resulting in massive amplification:
When the laser hit my image converter there was a red glare so intense it seemed to go right through my eyes and bounce off the back of my skull. It must have been only a few milliseconds before the converter overloaded and went blind, but the bright green afterimage hurt my eyes for several minutes.
(This is actually from the original short story Hero because I can't find my copy of TFW, but the plot point is in TFW, as I recall)....
We knew enough not to groan or anything, but there were some pretty disgusted looks, epsecially on the faces that had singed eyebrows and a pink rectangle of sunburn framing their eyes.
- In Gibson's Neuromancer, if you run afoul of sufficiently bad ICE you can actually
get electrocuted:
Sure. I was crazy. Figured I'd try to cut it. Hit the first strata and that's all she wrote. My joeboy smelled the skin frying and pulled the trodes off me. Mean shit, that ice."
"And your EEG was flat."
"Well, that's the stuff of legend, ain't it?"(Transcription here).
Now, whole volumes could be written about Gibson's ignorance of how computers work, but Haldeman was scientifically trained so it's a little more surprising coming from him, but both of these examples are basically nuts. You'd have to be nuts to build a system that could potentially pump enough energy into the human body to actually burn your skin.
The Neuromancer case is particularly egregious because you've presumably got some digital system plugged into your brain-computer interface, so it's just a simple matter of never giving the BCI enough voltage that it could potentially damage you. Even if you can't do that for some reason, it's easy to add physical voltage (e.g., zeners) or current limiting devices (e.g., fuses) to the leads to make electrocute you. This is pretty basic electronics and not really subject to circumvention no matter how malware infested your computer gets.
The Forever War passage is more interesting because at least in the past image intensifiers were quasi-analog devices. However, it's pretty hard to believe that one would make an amplification stage that could actually emit enough power to burn your skin in milliseconds, especially since the amount of energy emitted by the displays in analog image intensifier systems is partially gated on the relaxation time of the phosphors— no matter how many electrons you pump into the phosphor, it only phosphoresces so fast, so once all the molecules are in the excited quantum state, the electrons simply aren't absorbed. As I understand it, when standard night vision systems are overloaded (e.g., someone shines a light on them) they just stop working, not burn your face off. And of course any system in which the amplifier stage is digitally read and then displayed on a screen can be easily set with a maximum emission power. So, ultimately, I don't think getting burned by your image intensifier is a plausible story either, but I guess in both cases having your face catch on fire is more exciting than saying "my computer crashed".
Posted by ekr at November 29, 2007 7:30 PM | Filed under: Misc
Comments
A more effective plot device that I've seen recently is when the protagonist has some sort of programmable nano in his body. Then if an attacker can exploit a flaw in the nano control program and zombie the nano, spectacular physical effects can result.
Another variation is a programmable dispenser of psychoactive chemicals embedded in the brain that, under normal conditions, enhances mental performance but an attacker subverts it to "fry" someone's brain.
You really don't want to outsource the development of these systems' firewalls to those cheap programmer farms on Titan ;-)
Posted by: Kevin Dick at November 29, 2007 8:15 PM
You can continue with this line of argument but the chances of Lisa allowing you to augment yourself with neural implants is still less than zero.
Posted by: PHB at November 30, 2007 3:02 PM