tags : Math

Products

Inner product and Outer product are terms from “Geometric Algebra”

Inner product

works on abstract vector spaces

Dot Product / Scalar product

  • Intuition
  • Use
    • Way of turning two vectors into a number in a way that respects how long each vector is and how much the vectors overlap.
    • Can serve as a measure of how similar two vectors are.
  • Eg.
    • work is the dot product of force and displacement.
    • power is the dot product of force and velocity.

Outer product

Cross product

Wedge product

  • In differential topology, it works on differential forms and antisymmetrizes them to make a higher degree differential form.

Things people say

No one, and let me repeat that, no one “gets” linear algebra, differential equations, or frequency domain on the first pass. It takes years to absorb and multiple passes.

See:

Bruner / Spiral Curriculum.

Ebbinghaus / Spacing effect

Hattie / Deep-surface-transfer learning

Chunking (“How People Learn” has a good copy on this)

Etc.

The way you do this is you take a course, and then you take more courses. After a few years, it all connects and makes sense. The first course, I find, is often best short, simplified, and applied. Once you get through that, you can go deeper.

Different angles are nice too. For linear algebra:

  • Quantum computing

  • Statistics and probability

  • Machine learning

  • Control theory

  • Image processing

  • Abstract algebra / groups / etc.

  • Computer graphics

All come to mind.

On a mile-high level, this course seems ideal for a first pass. On a detailed level, I’m confused by some licensing issues.