What is light?
Is it a wave?
Is it a particle?
Or is it both?
Regardless of the truth, the wave-particle duality of light had already been written into high school physics textbooks.
90% of students merely remember there is such a concept.
A small number delve deeper, roughly grasping the double-slit interference experiment.
After this brief span of studying, the concept of light returned to examination papers, becoming a diverted line in a question where striking a mirror would reflect a symmetrical line, and by calculating the angles between them, one could retrieve the deserved marks.
But Jie Qifen stopped there.
A wave is a wave, a particle is a particle.
Duality?
What kind of explanation is this? What kind of concept is this?
The young man struggled to imagine why such an absurd description rightfully made its way into textbooks.
It's as absurd as stating, "someone exhibits both male and female qualities: they are female when dressed, and male when undressed."