On the Optimality of the Golden Code

In this note, we prove the optimality of the Golden Code inside the class of cyclic algebras based codes. In doing so, we get better insight on these algebraic codes, not only in dimension 2, but more generally for higher dimension, and summarizing the different approaches tried so far to optimize them, we derive design strategies that we believe are the key to either show the optimality of existing codes or give a way to improve them

Information geometric complexity of a trivariate Gaussian statistical model

We evaluate the information geometric complexity of entropic motion on low-dimensional Gaussian statistical manifolds in order to quantify how difficult is making macroscopic predictions about a systems in the presence of limited information. Specifically, we observe that the complexity of such entropic inferences not only depends on the amount of available pieces of information but also on the manner in which such pieces are correlated. Finally, we uncover that for certain correlational structures, the impossibility of reaching the most favorable configuration from an entropic inference viewpoint, seems to lead to an information geometric analog of the well-known frustration effect that occurs in statistical physics.Comment: 16 pages, 1 figur

From the function-sheaf dictionary to quasicharacters of pp-adic tori

We consider the rigid monoidal category of character sheaves on a smooth commutative group scheme $G$ over a finite field $k$ and expand the scope of the function-sheaf dictionary from connected commutative algebraic groups to this setting. We find the group of isomorphism classes of character sheaves on $G$ and show that it is an extension of the group of characters of $G(k)$ by a cohomology group determined by the component group scheme of $G$. We also classify all morphisms in the category character sheaves on $G$. As an application, we study character sheaves on Greenberg transforms of locally finite type N\'eron models of algebraic tori over local fields. This provides a geometrization of quasicharacters of $p$-adic tori.Comment: Added examples and incorporated referee's suggestions. To be published in Journal of the Institute of Mathematics of Jussie