In nineteen eighty-two, American researchers James Wilson and George Kelling wrote a report describing what they called the broken windows theory.

VOA: special.2009.03.03

His theory of Martian life became so complex that he made maps of cities and waterways on the planet.

VOA: special.2010.07.11

The theory explains that as the sea floor spreads, the tectonic plates are pushed and pulled in different directions.

VOA: special.2011.01.04

Another theory is that Kim Jong Un might try to build power by dismissing opponents and inciting South Korea.

VOA: special.2010.10.02

And at least in theory I can make those schools compete against each other for my services."

VOA: special.2010.07.26

In his early years, Mister Galbraith was greatly influenced by the economist Thorstein Veblen and his book, "The Theory of the Leisure Class."

VOA: special.2011.05.01

The Eubie Blake National Jazz Institute and Cultural Center offers classes in dance,music theory,theater and history.

VOA: special.2010.10.08

We tell about a new children's book on Charles Darwin and his famous theory .

VOA: special.2009.02.27

But Professor Gaechter says his team's theory was that punishment has only low costs because it needs to be used rarely and works as a threat.

VOA: special.2009.03.03

She developed the theory explaining how and why the ozone hole happens over Antarctica.

VOA: special.2009.03.13

He had published the "General Theory of Employment, Interest and Money" the year before.

VOA: special.2011.05.01

She said the discovery "supports the theory that some of life's ingredients formed in space and were delivered to Earth long ago by meteorite and comet impacts."

VOA: special.2009.09.30

But it is a scientific theory based on repeated observations, experiments,measurements and discoveries.

VOA: special.2009.12.01

And,the experiment proved the theory.

VOA: special.2009.03.03