|Steve Huth <HUTH@***.EDU>
|Particle physics and Invisibility
|Mon, 10 May 1993 12:01:54 -0700
warping the light that would normally bounce off a person around them
instead, thereby preventing an image from being formed by the reflected
photons. This view certainly explains why thermographic vision still
works, as many people have pointed out, the body is an active emitter of
thermal energy, which can be detected. This is indeed probably FASA's view,
considering how explicit they are that visible light and Ultrasound (which
are both incoming particles) are affected by the invisibility spell, but
thermographic (outgoing particles) is not. While this is certainly valid,
there is a misconception at its heart that leads me to think of invisibility
in a different way. Heat and light are really just streams of photons with
particular wavelengths in the electromagnetic spectrum. It is a common
misperception that light hits a person, bounces off, and is reflected into
our sight apparatus. Actually it is quite a bit more complicated than that.
Light in the form of photons hits a body and is ALWAYS absorbed. The atom
that absorbed the photon is thereby placed in an excited state and, seeking
to return to normal, emits a photon. It is this emitted photon that our
eyes perceive (ERROR alert--when I said "atom," I meant "electron"--I
hear my physics prof groaning from here--the rest is still accurate).
What does this mean? Well, actually very little. The view of invisibility
that says the incoming light is warped around a person is still accurate
(no incoming light means no excited electrons means no emissions in the
visible light portion of the EM spectrum). BUT, if you think of the
invisibility spell as absorbing the body's electromagnetic emissions,
then the invisibility spell not only stops visible light, but also the
photon emissions in the heat spectrum (thereby being effective against
thermographic vision). This leaves Ultrasound as a viable way of spotting
invisibility (sound waves are not photons which means they are not part of
the EM spectrum) while allowing invisibility to work against thermographic.
Personally, I happen to prefer this alternative, simply because the
physical process of warping the paths of photons strikes me as
nightmarishly difficult, whereas the absorption of emitted radiation is
fairly easy to understand. To which the proper reply, of course, is that
it's magic, who cares how difficult it is.
Just thought I'd spout for a while.
P.S. On a different topic, isn't it fun to watch Carter dig himself into a
hole on the issue of cybereyes and mages? Gotta agree with Crossfire, you
can't argue that a processed image prevents magic use, because all cybereyes
give the brain processed images. BTW, to those who argued that low-light
is ok because it just adds rods, I think that must be wrong. Adding rods
would be a bioware modification, not a cyber mod. Cyber low-light should
either work differently or be shifted into the category of bioware (no,
I don't know how cyber low-light should work). Come to think of it, didn't
Crossfire post bioware eye mods a couple months back that did exactly that
(adding rods, that is)? Fun debate to watch--personally I don't know
why FASA says e-mag can't work because it processes the image, but cybereyes
in general are ok. I suspect its another one of those issues where they
were looking for game balance and ignored strict logic.
P.S.S Just out of curiousity, who's going to be around this summer. I will
be, and I know Carter will as well. I hope a bunch of others will be,
because myself, Carter, Matuskey and a few of our friends are planning on
play-testing a pretty complete revamping of the decking system, making some
controversial changes to the magic system, and probably polishing our
combat mods (some of which were posted earlier and greeted with deafening
silence). I hope people are around to critique for us. For those who
won't be, have a nice summer--hope to see ya next year.