= Square-lattice Weierstrass function has a zero branch value
{title2=$\wp_{\mathbb Z+i\mathbb Z}((1+i)/2)=0$}
For the square <period lattice>, multiplying the defining series by the lattice symmetry $z\mapsto iz$ gives $\wp(iz)=-\wp(z)$. At $h=(1+i)/2$, one has $ih=h-1$, so periodicity gives $\wp(h)=-\wp(h)$ and hence the displayed zero. This is one of the three finite branch values of the degree-two <Weierstrass elliptic function> on its <torus>. The three values are always distinct but need not all be nonzero. Distinctness is enough for the nonsingularity of the associated <elliptic curve> $Y^2Z=4\prod_i(X-e_iZ)$.
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