Abel’s theorem in the noncommutative case

We define noncommutative binary forms. Using the typical representation of Hermite we prove the fundamental theorem of algebra and we derive a noncommutative Cardano formula for cubic forms. We define quantized elliptic and hyperelliptic differentials of the first kind. Following Abel we prove Abel’s theorem.     

Travelling Randomly on the Poincaré Half-Plane with a Pythagorean Compass

A random motion on the Poincaré half-plane is studied. A particle runs on the geodesic lines changing direction at Poisson-paced times. The hyperbolic distance is analyzed, also in the case where returns to the starting point are admitted. The main results concern the mean hyperbolic distance (and also the conditional mean distance) in all versions of the motion envisaged. Also an analogous motion on orthogonal circles of the sphere is examined and the evolution of the mean distance from the starting point is investigated.     

卡尔达诺几何证明的构造性

为分析与探索《大术》中几何证明的特点,对《大术》第13章中三次幂加上常数等于一次项方程解法法则的证明原文运用简单易懂的数学表达式作以说明;基于对此法则的证明,分析了卡尔达诺几何证明构造性特点,总结了卡尔达诺的构造思路.