Hearkening back to chapter 20, discussion of Google’s action of finding the shortest route to a relevant response, I want to tie in the action of lightning strikes to the discussion. Google uses exceptional speed and accuracy to transverse the billions of visible internet sites to locate the most relevant response to a given query. Similarly, as is colloquially known, lightning finds the shortest path to the ground. Although both tasks seems impossible given the multitude of possible routes that a query or a lightning charge might take, both rely on prior mapping in order to find the fastest route.
Just as Google “crawls” the internet to gain knowledge of the architecture of the internet’s sites before queries are made, lightning tests out routes in the air before releasing its current. The cloud sends out negatively charged “leaders” that branch in may different directions on on the way down from the cloud at 60 miles/second. These leaders are not the actual lightning strike, but rather a means of charting out the possible pathways that lightning might follow. When the leaders connect with a positive leader from a high ground object, the pathway is then open for the cloud to discharge in the form of a lightning strike. Thus, the speed of the observable event relies on the effectiveness of a broad planning/mapping procedure.
In terms of the theory of networks, we have used the idea of a person finding their way quickly across the city in the shortest time. There are many possible routes and they vary in distance. An individual can only see the turns that are directly in from of them and therefore are subject to the chance of finding a fast route. We use maps to avoid this problem by taking a prior survey of all routes and then selecting the faster one.