$$ \Large e^{i\pi} + 1 = 0 \qquad i = \sqrt{ -1 } \qquad e = \sum \limits _{n=0}^{\infty}{\frac{1}{n!}} = \lim _{n\to \infty} \left( 1 + {\frac{1}{n}} \right)^{n} $$
$$ \Large \pi = 2 \int_{-1 }^{+1}(\sqrt{1 - x^2})dx \qquad \int_{ -\infty }^{ + \infty } e^{-x^2 }dx = \sqrt{\pi} \qquad n! = \Gamma \left( n + 1 \right) = \int_{ 0 }^{ + \infty } x^{n}e^{-x}dx $$
$$ \Large i \hbar \frac{\partial \psi}{\partial t} = {\hat{H}} \psi \qquad \nabla ^{2} \Phi -{\frac {1}{v^{2}}}{\frac {\partial ^{2} \Phi}{\partial t^{2}}} = 0 \qquad {\frac {\partial \Phi }{\partial t } } = k \nabla ^{2} \Phi $$
$$ \Large R_{\mu \nu} - {1 \over 2}R g_{\mu \nu} + \Lambda g_{\mu \nu}= {8 \pi G \over c^4} T_{\mu \nu} \qquad \left( i \gamma^{\mu}\partial_{\mu} - m \right)\psi = 0 $$