This Video Explores Whether Photons Cast Shadows

Minutephysics explores this tricky question.
Loukia Papadopoulos

There are many objects on our planet that are good at blocking light. In fact, pretty much anything in the world blocks light and creates shadows.

But what about the smallest of particles such as photons. Do photons block light? That is the question that the good people at minutephysics decided to explore.

It may seem at first that they do not. This is because photons are electromagnetic waves and such waves can not interact with each other.

However, there are three indirect ways that photons can interact with each other. What are they? We won't tell you here. minutephysics does a much better job at explaining that then we ever could.