1) The document discusses the origins of Einstein's theory of relativity and how it stemmed from the ancient Greek concept of aether, which was thought to be the invisible medium permeating the universe through which light and other waves could propagate. 2) In the 19th century, James Clerk Maxwell's discovery that light is an electromagnetic wave led scientists like Maxwell to believe that aether must be the medium through which light waves travel, similar to how sound waves require air to travel. 3) Maxwell suggested an experiment to detect the motion of the Earth through the hypothetical aether medium by measuring the difference in the speed of light beams traveling perpendicular and parallel to the Earth's orbital motion around the Sun.

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WHERE DID ALL THESE EQUATIONS
COME FROM?
Cosmic Adventure Episode 2.05

2. © ABCC Australia 2015 new-physics.com
The Origin of
Relativity
It goes without saying that
Einstein’s theory of relativity
is one of the most
revolutionary ideas ever
produced by a human mind.
But it is quite marvellous to
think that this latest idea
had its origin in the oldest
fairy tale in ancient Greek
mythology. It all started with
the god aether.
Aether?

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Aether
The term ‘aether’
stemmed from a
Greek root
meaning ‘pure,
fresh air’, ‘upper
air’ or ‘clear sky’.
Somehow in
modern time, it
had become the
mysterious
substance that
pervaded the
entire universe.
Aether the first-born of the elemental gods. Painting By
Evelyn Pickering De Morgan, Night and Sleep, 1878.

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Light –
An Electromagnetic Wave
In the nineteenth century, aether exploded
into prominence when James Clerk
Maxwell discovered that light is an
electromagnetic wave.
As a wave, light needs a medium for its
propagation - just like sound waves which
need air as their transmission medium.
Maxwell thought that aether was the
medium for light.

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Light Speed Constancy
Secondly, the existence ofa
stationary aether medium
would provide a natural
explanation to the constancy
of light velocity without
further assumptions.
Electromagnetic waves

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The Absolute Frame in
Classical Mechanics
Thirdly, before Maxwell, the
renowned physicist Isaac Newton
also had aether to be the seat of
his absolute reference system in
space.

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Medium for Gravitation
Fourthly, aether might also
be the medium through
which the force of
gravitation was transmitted.
Gravitation

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Foundation of
classical Science
In short, aether is the very
foundation of classical
science. Without the
existence of the aether, all
the development of physics
up to the nineteenth century
would have been non-solid.

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The Detection of the
Aether
In the mid nineteenth century,
physicists were working hard to
find evidences to establish the
existence of the aether.
In the late nineteenth century,
many ingenious experiments had
been carried out in an attempt to
detect the existence of the
mysterious medium.
However, the aether had been so
elusive that all the experimental
results had turned out to be
negative.

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Light through Aether
Maxwell had a bright idea.
By using common sense,
Maxwell thought that aether
to light is just like air to
sound. Just as the speed of
sound is relative to the air, so
the speed of light must be
relative to the aether.
It is hard to measure aether,
but it should be possible and
much easier to measure the
motion of light through the
aether.
Hard to detect aether
Easier to detect wave

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In his article on the aether in
the ninth edition of the
Encyclopaedia Britannica,
Maxwell put forth his idea:
“If it were possible to
determine the velocity of light
by observing the time it takes
to travel between one station
and another on the earth’s
surface, we might, by
comparing the observed
velocities in opposite
directions, determine the
velocity of the aether with
respect to these terrestrial
stations.”

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Speed of Earth
However, in ordinary life, the ratio of 𝑣 to 𝑐 is so small that it is close to
zero. What about the earth? The earth is moving at a mean velocity of
29.78 or about 30 kilometres per second in its orbital motion around the
sun. This figure is a good percentage of that of light.
𝑐 + 𝑣
𝑐 − 𝑣
𝑣 = 30 kilometrse per
second

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Addition of Velocity
The idea was simple:
When a man speeds towards
a light source, light will
come to him faster;
When he receded, it would
took light a bit longer to
reach him.*
𝐴𝑝𝑝𝑟𝑜𝑎𝑐ℎ𝑖𝑛𝑔 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦
= 𝑐 + 𝑣
𝑅𝑒𝑐𝑒𝑑𝑖𝑛𝑔 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦
= 𝑐 − 𝑣
*
(Today, we know that this way of
adding light velocities classically is
wrong. But the practice was
prevalent at those times.)
This is the first fault in the theory.

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Relative Aether Wind
This means that the
undetectable aether wind
would be whistling through
the earth at a velocity of 30
kilometres per second just
like still air whistling pass a
speeding car.
The air is not actually
moving. It is the feeling of
moving wind that is created
by the movement of the car.
Wind created by speed of car
Relative wind speed created

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Adding Speeds of Light
In real numerical values:
The speed of light (c) is 300,000 km/s and the speed of the Earth (v)
orbiting the Sun is 30km/s.
When light rays head upstream against the Earth movement the speed is:
𝑐 𝑎𝑝𝑝𝑟𝑜𝑎𝑐ℎ𝑖𝑛𝑔 = 𝑐 + 𝑣 = 300,000 𝑘𝑚/𝑠 30 𝑘𝑚/𝑠
When the light rays head down stream in the same direction is:
𝑐 𝑟𝑒𝑐𝑒𝑑𝑖𝑛𝑔 = 𝑐 − 𝑣 = 300,000 𝑘𝑚/𝑠 − 30 𝑘𝑚/𝑠

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1878 Publication
In his 1878 Encyclopaedia Britannica
article Maxwell further suggested an
experiment to determine the velocity
of the earth through the aether
using light in the following way:
“Split a ray of light, and send the two
resulting rays at right angles to each
other. Let one travel at right angles
to the motion of the earth through
the aether while the other travels in
the direction of the motion of the
earth through the aether. . . .
Incominglight
Horizontal light
Verticallight
Splitting
Earth’s motion
Aether wind created

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Reflecting & Rejoining
Maxwell Continued:
. . . Reflect the two rays back after
each has travelled exactly the same
distance to join up again and let
them interfere.”
This must mean, if you could
measure the speed of light
accurately enough, you could also
measure the speed of light
travelling upwind. When compared
the sum of the two measurements
it should be twice the wind speed.”
Horizontal light
Verticallight
Rejoining
&
Interfering

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MICHELSON’ RIVER ANALOGY
To be continued on: Episode 2.06