The first ever photograph of light as both a particle and wave

There’s so much I don’t know!

When teaching rhetoric, I often use “Is light a wave, or is it a particle?” as an example of a false dichotomy.

My high school physics teacher (Rear Admiral Edward Metcalfe Peebles) set up a lecture giving us the “pro-wave” evidence and the “pro-particle” evidence and inviting us to take sides, then sprung the “wavicle” at us (a thing that sometimes acts like a wave and sometimes acts like a particle) so we’d notice our faulty thinking.

A FB friend recently shared this 2015 item on the first image of light operating as both a wave and a particle.

I wanted to make sure I wasn’t sharing a pretty computer simulation, so I’ve tried to understand what the image shows.

As I understand it, this is a “standing wave” of laser light, interacting with a nearby stream of electrons in such a way that we would expect from photons (individual light particles).

Ecole Polytechnique Federale de Lausanne, via

Vibrations of particles reacting to repeated pulses passing each other in opposite directions interact in such a way to create what appears to be a stationary wave, which is the source of light for the experiment.

As a stream of electrons passes near the stationary wave, individual electrons periodically interact with photons (the light particles, or I guess what we think of as particles, somehow connected to the part of light that makes up the wave), and the properties of the individual photos can be determined by how they interact differently with the (presumably identical?) stream of electrons.

I presume we wouldn’t see these intermittent distinct interactions if light were just a wave, and we wouldn’t see the “standing wave” effect if light were just particles.

The news item on “” is not written for the average person, so I’m not sure if my understanding is correct. (There’s a video that may explain in more detail… I didn’t watch it yet.)