1. INTRODUCTION. Among the theorems of plane geometry, a privileged position is held by those that are true in neutral geometry, that is, without either assuming or denying the parallel postulate. Such, for example, are the first twenty-eight propositions of Euclid's Elements, including the triangle congruences SAS (I.4), 1 SSS (I.8), ASA (I.26), and the base angles of an isosceles triangle are...

Dr. Adam B. Cohen (Neurology): A 59-year-old man was admitted to the neurology service of this hospital because of chronic daily headache, fever, and myalgia. Approximately 6 months earlier, the patient had begun having headache, accompanied by muscle spasms, generalized myalgia, weakness, fatigue, difficulty sleeping, and anxiety. The headache was constant, affected both temporal and frontal r...

The subject of Computational Convexity draws its methods from discrete mathematics and convex geometry, and many of its problems from operations research, computer science, data analysis, physics, material science, and other applied areas. In essence, it is the study of the computational and algorithmic aspects of high-dimensional convex sets (especially polytopes), with a view to applying the ...