Topological surgery in nature (Q1697081)

This paper reviews examples of topological surgery that arise in nature. Thus the breaking and recombination of DNA is an example of surgery on 1-manifolds if the DNA string is seen as 1-dimensional. A significant idea introduced by the authors is to view the process of surgery as continuous. Thus when a tornado cloud reaches down to the ground one can view this as a surgery on the cloud. The authors also introduce what they call a solid surgery. An example of this carried out on a solid 3-ball sees the ball as a 2-sphere crossed with an interval and one end identified to a point. The solid surgery performs a 0-surgery on each sphere in the product and explodes the central point of the disk to a circle. The authors use this to provide a model for the formation of black holes. Several other examples of natural surgeries are given, but this black hole example is the most developed. For the entire collection see [Zbl 1387.00028].