1847.
Faraday proposed that light is a high-frequency electromagnetic vibration, which can propagate without a medium.
If you extend time from the perspective of later generations, you will also find.....
It was based on this theory that Wheat discovered the phenomenon that self-generated electromagnetic waves propagate at a constant speed.
And this speed happens to equal the speed of light, leading to the conclusion that light is an electromagnetic wave.
Now learning that Xu Yun actually could provide evidence to refute the wave theory, how could Faraday remain calm?
So after entering the shed, his first sentence was:
"Student Luo Feng, is what you said true? You can provide evidence to refute the wave theory?"
Looking at this handsome older gentleman with pronounced features, Xu Yun's eyes showed a hint of respect, and he affirmed:
"Yes, Mr. Lafayette, Fat Fish Ancestor discovered certain phenomena by accident during the study of electrolysis."
