# Einstein, Hilbert, Newton and Lagrange

08 Dec 2021can you rewrite the Lagrange density of classical gravity, \(\mathcal{L} = \frac{(\nabla\Phi)^2}{2}-4\pi G\rho\Phi\) such that it contains a second derivative of \(\Phi\) instead of a square of first derivatives, making it more similar to the Einstein-Hilbert-density?