## Monday, January 23, 2017

### Cactus Spiral

In geometry, a golden spiral is a logarithmic spiral whose growth factor is φ, the golden ratio. That is, a golden spiral gets wider (or further from its origin) by a factor of φ for every quarter turn it makes. A golden spiral with initial radius 1 has the following polar equation:
See Wikipedia: Golden spiral

You can find many natural instances of the Golden Spiral if you look at plants. Cactus are particularly interesting examples. I am, as usual, facinated by the form of the natural world.