👉 In mathematical notation, "spiegels" is a term used to denote an algebraic object that can be expressed as a product of two or more variables. The term is often associated with the study of commutative algebra and its applications in number theory, but it has also been used in other areas such as physics. In particular, spiegels are important in studying the algebraic geometry of curves and surfaces, particularly in the context of the moduli space of curves. They can be