Albert Einstein

Reading audio



2005-2-22

VOICE ONE:

This is Steve Ember.

VOICE TWO:

And this is Sarah Long with the VOA Special English program,
Explorations. Today we tell about a scientist who changed the way we
understand the universe, Albert Einstein.

VOICE ONE:

Albert Einstein
Albert Einstein changed science.
(All Pictures NASA)

In the year Nineteen-Oh-Five,
Albert Einstein published some important papers in a German
scientific magazine. They included one of the most important
scientific documents in history. It was filled with mathematics. It
explained what came to be called his "Special Theory of Relativity."
Ten years later he expanded it to a "General Theory of Relativity."

Albert Einstein's theories of relativity are about the basic
ideas we use to describe natural happenings. They are about time,
space, mass, movement, and gravity.

VOICE TWO:

Albert Einstein was born in Ulm, Germany, in
Eighteen-Seventy-Nine. His father owned a factory that made
electrical devices. His mother enjoyed music and books. His parents
were Jewish but they did not observe many of the religion's rules.

Albert was a quiet child who spent much of his time alone. He was
slow to talk and had difficulty learning to read.

When Albert was five years old, his father gave him a compass.
The child was filled with wonder when he discovered that the compass
needle always pointed in the same direction -- to the north. He
asked his father and his uncle what caused the needle to move.

Their answers about magnetism and gravity were difficult for the
boy to understand. Yet he spent a lot of time thinking about them.
He said later that he felt something hidden had to be behind things.

VOICE ONE:

Albert did not like school. The German schools of that time were
not pleasant. Students could not ask questions. Albert said he felt
as if he were in prison.

One story says Albert told his Uncle Jacob how much he hated
school, especially mathematics. His uncle told him to solve
mathematical problems by pretending to be a policeman. "You are
looking for someone," he said, "but you do not know who. Call him X.
Find him by using the mathematical tools of algebra and geometry."

VOICE TWO:

Albert learned to love mathematics. He was studying the complex
mathematics of calculus when all his friends were still studying
simple mathematics. Instead of playing with friends he thought about
things such as: "What would happen if people could travel at the
speed of light?"

Albert decided that he wanted to teach mathematics and physics.
He attended the Federal Polytechnic Institute in Zurich,
Switzerland. He graduated with honors, but could not get a teaching
job. So he began working for the Swiss government as an inspector of
patents for new inventions. The job was not demanding. He had a lot
of time to think about some of his scientific theories.

VOICE ONE:

From the time he was a boy, Albert Einstein had performed what he
called "thought experiments" to test his ideas. He used his mind as
a laboratory. By Nineteen-Oh-Five, he had formed his ideas into
theories that he published.

In one paper he said that light travels both in waves and in
particles, called photons. This idea is an important part of what is
called the quantum theory.

Another paper was about the motion of small particles suspended
in a liquid or gas. It confirmed the atomic theory of matter.

The most important of Albert Einstein's theories published that
year became known as his "Special Theory of Relativity." He said the
speed of light is always the same -- almost three-hundred-thousand
kilometers a second. Where the light is coming from or who is
measuring it does not change the speed. However, he said, time can
change. And mass can change. And length can change. They depend on
where a person is in relation to an object or an event.

VOICE TWO:

Imagine two space vehicles with a scientist travelling in each
one. One spaceship is red. One is blue. Except for color, both
spaceships are exactly alike. They pass one another far out in
space.

Neither scientist feels that his ship is moving. To each, it
seems that the other ship is moving, not his. As they pass at high
speed, the scientist in each ship measures how long it takes a beam
of light to travel from the floor to the top of his spaceship, hit a
mirror and return to the floor. Each spaceship has a window that
lets each scientist see the experiment of the other.

VOICE ONE:

They begin their experiments at exactly the same moment. The
scientist in the blue ship sees his beam of light go straight up and
come straight down. But he sees that the light beam in the red ship
does not do this. The red ship is moving so fast that the beam does
not appear to go straight up. It forms a path up and down that looks
like an upside down "V".

The scientist in the red ship would see exactly the same thing as
he watched the experiment by the other scientist. He could say that
time passed more slowly in the other ship. Each scientist would be
correct, because the passing of time is linked to the position of
the observer.

Each scientist also would see that the other spaceship was
shorter than his own. The higher the speeds the spaceships were
travelling, the shorter the other ship would appear. And although
the other ship would seem shorter, its mass would increase. It would
seem to get heavier.

The ideas were difficult to accept. Yet other scientists did
experiments to prove that Einstein's theory was correct.

VOICE TWO:

Ten years after his paper on the special theory of relativity,
Albert Einstein finished work on another theory. It described what
he called his "General Theory of Relativity." It expanded his
special theory to include the motion of objects that are gaining
speed. This theory offered new ideas about gravity and the close
relationship between matter and energy. It built on the ideas about
mass he had expressed in Nineteen-Oh-Five.

Einstein said that an object loses mass when it gives off light,
which is a kind of energy. He believed that matter and energy were
different forms of the same thing. That was the basis of his famous
mathematical statement E equals m-c squared (energy equals mass
times the speed of light squared). This statement or formula
explained that a great amount of energy could come from a small
piece of matter. It explained how the sun could give off heat and
light for millions of years. This formula also led to the discovery
of atomic energy.

VOICE ONE:

The galaxies are evidence of a gravity lens--light bent by the force of gravity.<br />
The galaxies are evidence of a gravity lens--light bent by the force of gravity.

In his general theory of
relativity, Einstein said that gravity, like time, is not always the
same. Gravity changes as observers speed up or slow down. He also
said that gravity from very large objects, such as stars, could turn
the path of light waves that passed nearby. This seemed
unbelievable. But in Nineteen-Nineteen, British scientists confirmed
his theory when the sun was completely blocked during a solar
eclipse. Albert Einstein immediately became famous around the world.

Albert Einstein won the Nobel Prize for Physics in 1921.<br />
Albert Einstein won the Nobel Prize for Physics in 1921.

In Nineteen-Twenty-One, he won the
Nobel Prize in Physics. It was given to him, not for his theories of
relativity, but for his discovery of the law of the photoelectric
effect. This scientific law explained how and why some metals give
off electrons after light falls on their surfaces. The discovery led
to the development of modern electronics, including radio and
television.

VOICE TWO:

Albert Einstein taught in Switzerland and Germany. He left
Germany when Adolph Hitler came to power in Nineteen-Thirty-Three.He
moved to the United States to continue his research. He worked at
the Institute for Advanced Study in Princeton, New Jersey. Einstein
became a citizen of the United States in Nineteen-Forty.

VOICE ONE:

Einstein was a famous man, but you would not have known that by
looking at him. His white hair was long and wild. He wore old
clothes. He showed an inner joy when he was playing his violin or
talking about his work. Students and friends said he had a way of
explaining difficult ideas using images that were easy to
understand.

Albert Einstein opposed wars. Yet he wrote to President Franklin
Roosevelt in Nineteen-Thirty-Nine to advise him that the United
States should develop an atomic bomb before Germany did.

Einstein spent the last twenty-five years of his life working on
what he called a "unified field theory." He hoped to find a common
mathematical statement that could tie together all the different
parts of physics. He did not succeed.

Albert Einstein died in Nineteen-Fifty-Five. He was seventy-six
years old.

VOICE TWO:

This Special English program was written by Marilyn Christiano
and produced by Paul Thompson. This is Sarah Long.

VOICE ONE:

And this is Steve Ember. Join us again next week for another
Explorations program on the Voice of America.


Category