My brilliant idea

April 16, 2005

Albert Einstein, that most iconic of scientists, died 50 years ago on 
Monday. Deborah Smith reports on his influence in the 21st century.

When it comes to gravity, astronomers at the Parkes radio telescope 
have found that Einstein's predictions were astonishingly accurate. 
But as to the speed of light never changing, the great man got it 
wrong, other Australian physicists claim. And just north of Perth, 
researchers are searching for the gravity waves that he declared 
pervade the universe but which no one has yet been able to detect.

The scientist with the iconic shock of white hair transformed our 
understanding of the cosmos. And 100 years later his theories are 
still being explored, confirmed and challenged.

This year is the centenary of Einstein's "miracle year" of 1905 when, 
as a 26-year-old, he published four revolutionary ideas in a burst of 
creativity. Monday is the 50th anniversary of his death.

"Einstein was fantastic the way he came up with all these things that 
have stood the test of time. He's certainly worth celebrating," says 
Dr Dick Manchester, of CSIRO's Australia Telescope National Facility.

Events to mark 2005 as the Einstein International Year of Physics 
have been held around the globe. Here the anniversary has helped draw 
attention to an exceptional Australian physicist who came up with one 
of Einstein's most practical equations - but not the most famous one -
 a year before he did.

William Sutherland may not be well-known now, but in 1905 the young 
scientist was much more eminent than Einstein in the physics world. 
He lived with his sister, an artist, in Melbourne, devoting his life 
to research, according to Professor David Jamieson, president of the 
Australian Institute of Physics.

In 1904, most scientists didn't believe atoms were real. Sutherland 
assumed they existed, which could explain the strange jiggling of 
particles suspended in water, known as Brownian motion.

The Australian came up with an equation to explain how complex fluids 
diffuse in water, and published it. Then Einstein separately hit upon 
the same equation a few months later, in April 1905, by analysing 
sugar solutions. It was one of Einstein's most frequently cited 
findings because of its practical applications, but it should have 
been called the Sutherland-Einstein equation, one of Einstein's 
biographers, Abraham Pais, has argued.

Einstein's "annus mirabilis" began a month earlier, when, as an 
obscure patent clerk with a mediocre academic record, he published a 
paper on light that later won him a Nobel Prize. In June his third 
big idea, the special theory of relativity, was published. And in 
September he capped the year off with his famous equation, E=mc2, 
which some have likened to the mathematical equivalent of a perfect 

It took him until 1915 to complete his general theory of relativity. 
One of his students in philosophy and physics in Berlin at the time 
was a young woman, Ilse Rosenthal-Schneider, who retained a lifelong 
friendship with the famous scientist, even after she had fled to 
Sydney in the 1930s.

They often took the same tram to university. "I had ample time to 
pester him with my questions," she told this reporter in 1983, at the 
age of 91.

Einstein used to tease her, saying philosophical debates were like 
writing in honey. "It looks wonderful at first sight. But when you 
look again it is gone. Only the smear is left." One of Rosenthal-
Schneider's fondest memories was Einstein handing her a cable during 
a discussion. It was news that Sir Arthur Eddington's observations of 
a solar eclipse had confirmed Einstein's general theory of relativity.

She asked the scientist what he would have done if the results had 
not matched his ideas. "Then I would have to be sorry for dear God. 
The theory is correct," he told her.

Eddington's team made their observations from Brazil and the island 
of Principe in 1919. While the results turned Einstein into a 
household name, not all scientists were convinced by their 
accuracy. "The data analysis was very dodgy," says Jamieson.

A total solar eclipse in Australia in 1922 gave researchers a second 
opportunity to test whether reality matched theory and whether light 
that passed near a massive body such as the sun would be bent by the 
gravitational force, as Einstein had predicted.

American astronomers from the Lick Observatory in California were 
reportedly treated like celebrities on their mission near Broome, 
which confirmed Einstein was right.

The force of gravity is much stronger around pulsars - spinning, city-
sized neutron stars weighing more than the sun - than around normal 
stars. "So they provide a much more stringent test of Einstein's 
theory," says Manchester.

He is part of a team that last year identified a unique pair of 
pulsars which are orbiting each other. It has proved to be "a 
magnificent laboratory" to test the theory, and his team also found 
Einstein got it right. "General relativity is really very accurate."

This means ripples in space-time are being sent out by pulsars and 
collisions between black holes. Scientists who have built 
observatories in the US and Germany to try to find these 
gravitational waves have enlisted the help of more than 50,000 people 
with home computers to provide the power to crunch their data. This 
Einstein@home program runs while the computer is idle.

An Australian physicist, Professor David Blair, of the University of 
Western Australia, pioneered research into gravity waves, and was 
appropriately awarded the ANZAAS medal in this Einstein year for his 
more than 25 years of work that has led to the building of a detector 
at Gingin, 85 kilometres north of Perth. It is one of six 
observatories in the world using highly sensitive lasers directed 
down two long vacuum tunnels.

At Parkes Manchester is also developing a system he hopes will detect 
gravity waves "on the cheap" within five years by closely observing 
more than 20 pulsars. "Gravity waves would open up a new way of 
looking at the universe. Detecting them would be exciting, to say the 
least," he says.

If other Australian physicists can prove that the speed of light is 
not constant but has been slowing down, and Einstein's special 
relativity theory is wrong, it would mean there is a completely new 
set of laws that govern the universe waiting to be discovered.

Dr Michael Murphy this week caused a stir by presenting results of a 
study of 143 incredibly bright, distant celestial objects known as 
quasars using the Keck Telescope in Hawaii. They reveal that the fine 
structure constant - a measure of how light and matter interact, on 
which the speed of light depends - has changed by a tiny amount since 
the Big Bang. Other researchers who have carried out a similar study 
using the Very Large Telescope in Chile dispute this finding. But 
Murphy, now at the University of Cambridge, and his colleagues are 
analysing their own larger set of observations from Chile.

The jury is still out, he says. "We are claiming something 
extraordinary here, and the evidence, though strong, is not yet 
extraordinary enough."

Einstein's annus mirabilis

In 1905 Einstein wrote a series of scientific papers for the leading 
physics journal Annalen der Physik. These papers changed the 
understanding of the universe.

March 1905 Quantum theory of light: Einstein argued that light 
behaved as if it was composed of tiny particles, which he called 
photons. The view that the universe was built out of small, discrete 
chunks of energy and matter was the basis of quantum mechanics. It 
helped explain why electrons are emitted by some substances when 
light or other radiation is shone on them (the photoelectric effect). 
He won the 1921 Nobel Prize for this work.

April and May 1905 Existence of atoms: Einstein showed the existence 
of atoms, a hotly debated topic at the time, could be verified by 
measuring the strange jiggling of particles suspended in water, known 
as Brownian motion. He invented a new way to determine the size of 
atoms or molecules.

June 1905 Special relativity: Einstein developed the concept of 
relativity, a new theory based on the assumption that nothing can 
travel faster than the speed of light. He showed that distance and 
time vary with the motion of the person observing them, although this 
effect is only noticeable at incredibly high speeds.

September 1905 E=mc2: Einstein showed energy and matter are different 
forms of the same thing and linked by the most famous equation in 
physics: E=mc2, where E is energy, m is the mass of an object and c 
is the speed of light. The development of the atomic bomb 
demonstrated he was right.