algebraic geometry - Why does it suffice to show that $x$ is closed in every affine open subset $V$ that contains it? - Mathematics Stack Exchange
INTRODUCTION TO ALGEBRAIC GEOMETRY, CLASS 8 Contents 1. Morphisms of prevarieties 1 2. Examples of morphisms 3 Correction. Brian
If an affine variety is isomorphic to a projective variety, then it consists of only one point. How is that (Hartshorne)? - Quora
algebraic geometry - Sheaf of ideals of composition of closed immersion with clopen immersion - Mathematics Stack Exchange
definition - What does Liu mean by "topological open/closed immersion" in his book "Algebraic Geometry and Arithmetic Curves"? - Mathematics Stack Exchange