One of the big news stories last week was the publication in Science on the genomic sequence of a hundred year old Aboriginal Australian. The analysis finds that the Aboriginal Australians are descendants of an early migration to Asia between 62,000 and 75,000 years ago and this migration is different from the one that gave rise to modern Asians 25,000 to 38,000 years ago. I have often been amazed that humans were able to traverse over harsh terrain and open water into the complete unknown. However, I briefly watched a documentary on CNBC last night about Apocalypse 2012 that made me understand this much better. Evidently, there is a fairly large group of people who believe the world will end in 2012. (This is independent of the group that thought the world would end earlier this year.) The prediction is based on the fact that a large cycle in the Mayan calendar will supposedly end in 2012. According to some of the believers, the earth’s rotation will reverse and that will cause massive earthquakes and tsunamis. These believers have thus managed to recruit followers and start building colonies in the mountains to try to survive. People are taking this extremely seriously. I think this ability to change the course of one’s entire life on the flimsiest of evidence is what led our ancestors to leave Africa and head into the unknown. People will get ideas in their head and nothing will stop them from pursuing them. It’s what led us to populate every corner of the world and reshape much of the surface of the earth. It also suggests that the best optimization algorithms that seek a global maximum may be ones that have some ‘momentum’ so that they can leave local maxima and head downhill to find higher peaks elsewhere.
2 thoughts on “Action on a whim”
“It also suggests that the best optimization algorithms that seek a global maximum …”
When the fitness landscape is rough with many local minima the best method is simulated annealing. It doesn’t work by momentum but by somewhat “random jerks” of diminishing amplitude.
I should not have used the word “best” because, as you probably know better, optimization is as much art as science.