I am fairly new in Mathematica and I am trying to work with scalars and vectors. I decided to denote vectors using OverVector (as example, `OverVector[F]`stands for the force). Any scalar is denoted by a symbol. When an expression has a multiplication between scalar and vector, the expected outcome should be *nullVector*, but Mathematica evaluated this as zero. (I have been using Notation package and `Notation[OverVector[0]\[DoubleLongLeftRightArrow]nullVector]`, *nullVector* stands for the zero vector) How I can prevent Mathematica to evaluate `Times[OverVector[F],0]` as zero? In other words. I need Mathematica evaluates the multiplication between vector and zero as the zero vector (nullVector) not as zero. How I can get this? Thank you so much.