# Rulers and Protractors Become General Relativity

Eric believes General Relativity can be explained in a way most people can understand, and this explanation he wishes to have animated

## Eric's Explanation from Discord[edit]

Rulers and Protractors --> Derivative

Derivative --> Rise over run where run is measured above an implied horizontal

Horizontals form "Penrose Steps" --> Degree of Penroseness is measured by the Riemmann Curvature Tensor.

Curvature Tensor breaks into 6 Pieces, 3 of which are zero. --> Throw away non-zero Weyl Component and rebalance the other two non-zero components.

Set rebalanced remaining two components equal to the matter and energy in the system.

## Breakdown of the description for discussion purposes[edit]

0.5 ...when I have to describe what General Relativity is, and I don't wish to lie the way everyone else lies (if I'm going lie I'm going to do it differently) I say that:

1. You have to begin with 4 degrees of freedom

2. And then you have to put rulers and protractors into that system so that you can measure length and angle.

3. That gives rise miraculously to a derivative operator that measures rise over run

4. That rise is measured from a reference level

5. Those reference levels don't knit together

6. And they form Penrose stairs

7. And the degree of Escherness, or Penroseness, is what is measured by the curvature tensor

8. which breaks into three pieces

9. you throw one of them away, called the Weyl curvature

10. you readjust the proportions of the other two

11. and you set that equal to the amount of stuff.

12. It is linguistically an accurate description of what General Relativity actually is.

13. It also illustrates cohomology

## Links[edit]

- Eric explaining this on Episode 20