I have heard that humans have a wavelength. Is this true?

In 1932, a French scientist named Louis de Broglie suggested that the wave-particle duality applied to not only light, but also to matter. That is to say, he proposed that all matter possessed wave-like characteristics. To understand how he arrived to this conclusion, we must explain how light can possess both wave and particle properties.

Until the eighteenth century, light was thought of purely as a wave, like sound. There were several problems associated with this theory, however, one of the foremost being the lack of medium in space. Waves require a medium through which to travel, and without such substance, the wave cannot exist - - this is why sound cannot travel through a vacuum. In space, however, there did not appear to be any medium that would allow light to travel, yet light obviously traveled through space to reach the Earth. In order to explain this, scientists visualized a material that existed everywhere and through which light could propagate. This material came to be called the 'luminiferous ether'. The wave theory was further promoted when, in 1803, a scientist named Thomas Young demonstrated the interference of light in the famous 'double slit experiment'. This experiment could only be explained by the wave-nature of light.

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