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Pure light was born long ago in the Big Bang
and it still travels throughout the Universe. The
color variations we see, from the green grass to
the blue-tinted sky, are a result of light
interacting with the molecules in the three types
of matter: solid, liquid, and gas. How each
variation selectively reflects and absorbs, or
refracts and scatters determines what color we
see.

The first thing the might baffle one about
light is the so called wave-particle duality. This
is, light behaves as if it were a wave like sound
waves, but it also behaves as a particle, called
photons. To better understand this, lets look at
an experiment conducted by John Wheeler in 1980.
Wheeler proposed an especially incisive "delayed
choice" single photon experiment. The test is to
turn on the source and allow the photon to
encounter two holes in a screen, and then wait
before installing either one detector behind each
hole (single photon test), or a strip of
photographic film (the wave interference test).
What is the status of the light after passing
through the openings, but before selecting a test
for particle or wave? Several experiments of this
nature show that light maintains its duality after
encountering the holes and then is still seen as
either particle or wave by the appropriate
detectors, chosen in mid flight. That is, if we
select the particle type of detection, the photon
acts as if it had passed through only one hole,
but if we chose to detect for interference, the
photon acts as if it had passed through both
holes! Can our decision to install one detection
system or another really change the history of the
photon? I think the more likely explanation is
that the ambiguity of light is so profound that we
hardly know how to consider it.

Another cool way to think of photons is for
them, moving at the speed of light all lengths
contract to 0, a photon would see infinitely thin
cosmos. Also, time is dilated to the point where
it stops, that is, the photon would experience no
time at all. Photons are timeless, existing
forever in the present moment of now; as if speed
were the preservative that keeps it immortal.

As a photon loses energy, it does not slow
down. Its wavelength and frequency are stretched,
making it shift towards the red end of the
spectrum, hence the name: red shift. Consider that
red light's frequency is 400 nanometers
(billionths of a meter), or 400 trillion hertz.
Violet is 740 nanometers, or 740 trillion hertz.
In the alternate language of photons, who's energy
is proportional to frequency, violet photons carry
nearly double the energy of those in red.

The Future of Light

Fiber optics is one of man's most successful
uses of light. A fiber represents a highly refined
art of glass making. The glass is drawn into a
strand, typically 100 micrometers across, by
extruding the molten tip of a glass rod. In
service, light races down the fiber without
shining through the sides because the fiber is
made with a central core nested in a sheath of
glass with a slightly higher refracting index. The
glass is made of silicon dioxide and sand, the
same ingredients as in ancient glass, but greatly
purified. With only a few foreign atoms for every
billion molecules of wanted material, it is the
most transparent substance ever made. It is most
transparent to light with wavelengths between 1.3
and 1.6 micrometers, so systems use infrared
light. In theory, light can be transmitted through
optical fiber with a bandwidth of thousands of
gigahertz. It is capable of telephone information
transfer at nearly 2 billion bps (bits per
second). That translates to real time video
transfer, and almost instantaneous data
exchange.

In 1993, a prototype general purpose computer
the employed light exclusively was demonstrated
at the University of Colorado. Instead of data
being represented by electrons stored in silicon
chips, its bits are pulses of light that
continually circulate through three miles of
optical fiber. By accurately timing the pulses
over carefully measured distances, the system
tracks each binary one and zero: a twelve foot
shaft of light and dark patch, respectively.

The ghostly switchyard for bits, operating at
light speeds and high frequencies, is bewildering
enough, but work is being done on a more complex
system. The directed beams of light would not use
optical fibers, they would simply transmit data in
open space. Using light speed, I believe, is next
step in constructing Artificial Intelligence.
Refer to Commander Data's neural net. It pulses
with light signals. I believe that speed of light
data transmission is essential to AI computers
with the abilities of the human brain.