Simons-type inequalities for minimal surfaces with constant Kähler angle in a complex hyperquadric

In this paper, we establish Simons-type inequalities and obtain some pinching theorems for compact minimal surfaces with constant Kähler angle immersed into a complex hyperquadric, and we characterize all these minimal surfaces when equality holds in the pinching theorems.     

Minimal surfaces and Schwarz lemma

We prove a sharp Schwarz lemma type inequality for the Weierstrass–Enneper parameterization of minimal disks. It states the following. If $F:\mathbf{D}\to \Sigma$ is a conformal harmonic parameterization of a minimal disk $\Sigma \subset {\mathbf{R}}^3$, where $\mathbf{D}$ is the unit disk and $\left|\Sigma \right|=\pi R^2$, then $\left|F_x\left(z\right)\right|(1-{\left|z\right|}^2)\le R$. If for some $z$ the previous inequality is equality, then the surface is an affine image of a disk, and $F$ is linear up to a Möbius transformation of the unit disk.     

Minimal models for graph-related (hyper)operads

We construct explicit minimal models for the (hyper)operads governing modular, cyclic and ordinary operads, and wheeled properads, respectively. Algebras for these models are homotopy versions of the corresponding structures.