"We shape the clay into a pot, but it is the emptiness inside that holds
whatever we want" Lao Tsu.
what is space?
the sun shines, nor moon nor star..." Kathopanishad
But what is light?
From ancient times these questions have come down to us. How many minds have wondered about the nature of space and
light? How many songs? How many hymns? In the 1700's Euler, the great mathematician, wrote to a German princess, "This
is, beyond question, one of the most important inquiries in physics."
In the 1600's, with the help of a prism, Newton had separated sunlight into its constituent
colors which he thought of as its "least parts". He thought of light as corpuscular. "Are not the rays of light
very small bodies emitted from shining substances?" He thought that the colors were made by corpuscles of different sizes.
The corpuscles were thought to travel as the planets travel, according to Newton's laws of motion. Left alone they traveled
in straight lines.
For many years
Newton's view swept the field. But why don't corpuscles collide?
Gradually at the hands of Huygens, Young, and Frensnel, Euler's notion that light might be a vibration
like sound began to gain ground. But if light, like sound, was a wave motion, it required a medium for its transmission. Space
could no longer be empty. Space must be filled with a material substance which came to be called the luminiferous ether.
But how could the ether be sufficiently rigid
to transmit the vibrations at the speed of light and yet let the planets pass through it?
Then came Faraday with the discovery of electromagnetic induction.
There were lines of force through space. There were electric and magnetic fields. Space was filled with fields, and the fields
were filled with energy. There were gravitational fields and electromagnetic fields. And Maxwell suggested that light was
an electromagnetic wave through space, through the luminiferous ether.
Then came Michelson and Morley. But no one could find the ether. Then came Planck
and Einstein. Light, whether a wave or a particle, was quantized. And the energy of the quanta was Planck's constant times
the frequency (E=hv). As Newton had suggested long ago, the color is related to the size (in this case energy) of the quanta.
G.N. Lewis, who used the term "jiffy" for the length of time it takes light to cross a centimeter, called the quanta
"photons". But the speed of the photons, with respect to the observer, is independent of the observer's motion through
space. So Einstein thought that we could keep the photons, but who needs the ether? The photons, like fish out of water, were
without the sea of the luminiferous ether in which to swim. But wait! Einstein put time into our geometry with space (where
it belongs) so what does that do to our space? What we say now is that, "Matter tells space-time how to bend and space-time
tells matter how to move" [Ref: Wheeler]. And, as Swami Vivekananda [a Vedantist monk and lecturer who visited the U.S.
twice around the turn of the century] suggested to Tesla in the winter of 1895-96, that what we see as matter is just potential
energy (E=m). Matter is wound up against space-time and space-time is wound up against [matter].
But what happens to our light?
In the four dimensional geometry of space-time we see things at
a distance by seeing them in the past. The separation between the emission events and the absorption events of the photons
goes to zero, and even the fish are gone. We are left with a universe which looks more like a dream. The separation between
the perceiver and the perceived goes to zero because space and time come into Einstein's equation as a pair of opposites.
( , where x and t are the space and time separations between the two events, and S is the total space-time separation between
those two events.) What we see as a light-year away, we see as a year ago, because the time comes in squared with a minus
But what are the fields and
what are the forces? What is the gravitational attraction, what is electricity, and what is inertia? And, what could exist
in the absence of space and time?
exists in the absence of time must be the changeless, since change takes place only in time. And whatever exists in the absence
of space must be infinite and undivided, since smallness and dividedness can only exist in space. But how does it show in
space and time? Is gravity the undivided? And is love? Is electricity the infinite? And is our yearning for freedom? And is
inertia the changeless, and is our yearning for peace? Are gravity, electricity, and inertia simply the underlying existence
as we see it in space and time? Light has been reduced to the emission and absorption events and the photons are gone. Space
and time have been reduced to a pair of opposites with zero separation between the perceiver and the perceived. So, the dream
is in the dreamer, but the dream is alive, because the underlying existence shows through us in what we see.