Double-slit interference.
This should be a widely known piece of physics knowledge.
A long time ago, the explanation of light's nature in the physics community was split into two camps:
One believed light was a particle, the other thought light was a wave.
As for the later emergence of the Ancient Wave School, that's not discussed here.
At that time, both camps had sufficient evidence, and neither could convince the other.
Later, physicists came up with a way:
To use the double-slit interference experiment to determine whether it's a particle or a wave.
The experiment is actually quite simple.
Double-slit, as the name implies.
It involves opening two slits in a barrier.
Then use a photon-emitting machine gun to fire at the double slits.
The photons that pass through the slits hit the screen behind, leaving a light spot.
Before the experiment, the experimenters had two hypotheses:
The first possibility.
If photons are pure particles, the screen must leave two bars.
