Hi, I'm Christina Hartman for About.com and today we're profiling the Danish physicist Niels Bohr.Niels Bohr was born in October of 1885 in Copenhagen. Though he enrolled in the University of Copenhagen to study philosophy and mathematics in 1903, Bohr soon discovered an interest in physics and graduated with his doctorate in 1911. The next year, Bohr went to England and spent time studying and working at Manchester University with some of the foremost nuclear scientists of the day, including Ernest Rutherford.It was while in Manchester that Bohr formulated his theory on the structure of the atom. Bohr suggested that the atom was composed of a tightly packed, positively-charged nucleus surrounded by electrons that travelled in circular orbits. The model's success lay in that it helped explain the spectral emission lines of hydrogen. And through this theory, Bohr also founded the basis for quantum mechanics.In 1922, he was awarded the Nobel Prize in Physics for his theory. He also developed the concept of complementarity in quantum mechanics -- the idea that something can be separately analyzed as having contradictory properties, for example that light behaves as both a wave and a stream. Albert Einstein preferred the idea of classical physics in contrast to Bohr's new quantum mechanics and the two had numerous friendly debates over the topics which became known as the Bohr-Einstein debates.As World War II scaled up in Europe, Bohr fled Denmark to Sweden but also spent time in Britain where he was introduced to the Manhattan Project and was brought on board as a consultant by the Americans. Bohr and J. Robert Oppenheimer wanted to share the technology with the Soviets to more quickly bring about a result, but were unable to convince British Prime Minister Winston Churchill to agree.Bohr returned to Denmark after the war and advocated the peaceful use of nuclear energy. He died in November of 1962. While his model of the atom has since been shown to not be entirely accurate, it is still used as an introductory model to atomic physics.And that's a look at the Danish physicist Niels Bohr. For more information, be sure to check out About.com.