Colm Kelleher explains how scientists spent many years trying to understand how the source of light is reflected off of objects, and how our eyes observe two beams of light crossing each other independently.

Light makes interference patterns like waves, where particles collide into each other. However, new research shows some instances where light acts like a particle. For example, when a light is shown on metal, it’s particles are transferred into the object allowing it to heat up.

Nelson Diaz, the animator of the video, provides illustrations of examples that demonstrate when a light behaves like a particle, a wave, or neither.

Image provided by TED-Ed

Sourced: TEDEducation

Curated: @KatherineNader, an online editor at Arbitrage Magazine, and author of The Deadly Mark. She is a student of Biology, English, and Professional Writing at the University of Toronto.