And Martha all I had was you and all you had was me
Physicists and cosmologists have long noted that the laws of physics seem remarkably well tuned to allow the existence of life, an idea known as the anthropic principle.
It is sometimes used to explain why the laws of physics are the way they are. Answer: because if they were different, we wouldn’t be here to see them.
To many people, that looks like a cop out. One problem is that this way of thinking is clearly biased towards a certain kind of carbon-based life that has evolved on a pale blue dot in an unremarkable corner of the cosmos. Surely there is a more objective way to explain the laws of physics.
Enter Raphael Bousso and Roni Harnik at the University of California, Berkeley and Stanford University respectively. They point out that the increase in entropy in any part of the Universe is a decent measure of the complexity that exists there. Perhaps the anthropic principle can be replaced with an entropic one?
Today, they outline their idea and it makes a fascinating read. By thinking about the way entropy increases, Bousso and Harnik derive the properties of an average Universe in which the complexity has risen to a level where observers would have evolved to witness it.
photo { Jocelyn Lee }
