Daniel Baron

What is life, and how do we know it when we see it? These arephilosophical questions and may not concern us overmuch in ourday-to-day lives, but they are of great practical import in the growing fieldof astrobiology: the search for life on planets beyond our own. ErwinSchr ̈odinger famously suggested that life’s central distinguishingcharacteristic is a state of very low “entropy” compared to its environment.Astrobiologists Azua-Bustos and Vega-Martinez, inspired by this idea,have developed a method for detecting the presence or absence of life byanalyzing the fractal entropy of image data. In this talk, I will explain thebasics of Shannon’s entropy (a way to quantify the amount of uncertaintyor “surprise” in an information source or unknown outcome, and acornerstone of communication theory) and of fractals (sets that seem to fillspace more completely than their topological dimension would suggest,and that continually reveal more detail as you “zoom in”). There is asurprising connection between the two! I will then discuss Azua-Bustos’and Vega-Martinez’ research in light of these mathematical theories.