This is a test for post cover image.
\[\dfrac{\partial\mathcal{L}}{\partial\varphi}-\partial_\mu\dfrac{\partial\mathcal{L}}{\partial(\partial_\mu\varphi)}=0\]This is a test for post cover image.
\[\dfrac{\partial\mathcal{L}}{\partial\varphi}-\partial_\mu\dfrac{\partial\mathcal{L}}{\partial(\partial_\mu\varphi)}=0\]