Lorentz invariance of wave eqn.

AI Thread Summary
The discussion centers on demonstrating the Lorentz invariance of the classical wave equation. The user attempts to apply the chain rule to transform derivatives but encounters difficulties in the process. They suggest substituting transformed coordinates back into the equation instead of using the chain rule explicitly. The conversation highlights the challenges in proving Lorentz invariance and the need for clarity in applying transformations. Ultimately, the goal is to show that the wave equation remains unchanged under Lorentz transformations.
Hymne
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Hello! Hopefully somebody could give me a push from behind on this one :)

Homework Statement



Show that the classical wave equation is lorentz invariant.

The Attempt at a Solution


I tried to exchange all derivatives by the chain rule:

(c^2 \frac{d^2 }{dt^2} + \frac{d^2 }{dx^2} + \frac{d^2 }{dy^2} + \frac{d^2 }{dz^2}) \phi = 0 ; \quad<br /> <br /> \frac{d}{dx} \rightarrow \frac{d}{dx}\frac{dx}{dx&#039;}
And the same for the time derivative and use lorentz transformation. But somewhere it goes wrong..
 
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I'd just substitute in the transformed coordinates and boil it all back down to what it started as. Not sure I'd use the chain rule explicitly.

Adrian.
 
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