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  Aristotle was a Greek philosopher and did not believe in the atomic theory. He believed that humans contained fire, water, air, and earth.
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  Democritus was a philosopher. Democritus believed that everything in the world contains atoms.
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  John Dalton was a chemist, meteorologist and physicist. He is mainly known for his work towards the modern day atomic theory.
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  J.J. Thomson was a British physicist. J.J, won the Nobel Peacde Prize in 1906 in the Physics department. J.J. was well known for his discovery of the electron.
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  Nagaoka was a Japanese physicist. Nagaoka was known for his incorrect model of the atom.
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  Ernest Rutherford was a chemist and a physicist. He claimed that atoms have their positive charge concentrated in a very small nucleus.
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  Niels Bohr was a Danish physicist. He beleived that electrons traveled in circular waves around the atom.
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  Erwin Schrodinger was a physicist. Erwin was a father of quantum mechanics. Schrodinger suggested that electrons travel in a wave around the protons and neutrons.