Then Wheat took a deep breath and focused all his thoughts on simplifying the formula.
In his previous life, when Xu Yun was writing novels, a reader once raised a rather high-quality question.
In 1746 the one-dimensional wave equation already appeared, so why do we need to re-derive the formula?
The answer is simple:
Although D'Alembert had researched the one-dimensional wave equation, what he came up with was the initial solution for a traveling wave.
This kind of solution is also called the general solution, and it's actually very, very different from the wave equations of later generations.
What Xu Yun listed this time is the general solution from 1865, so there is no such "bug" as "the wave equation hasn't been derived yet in this worldline."
Not to mention anything else.
Just the thinking process required for Fourier transformation in the classical wave equations wouldn't be published by Fourier in his "Analytical Theory of Heat" until 1822.
