Optical illusions occur when what the eyes see conflicts with what the brain expects.
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In 1999, Harvard physicist Lene Hau was able to slow down light to 17 meters per second and in 2001, was able to stop light completely.
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Aluminum used to be more valuable than gold!
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Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
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The only letter not appearing on the Periodic Table is the letter "J".
180
A cesium atom in an atomic clock beats over nine billion times a second.
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