For the John Templeton Foundation, I wrote about the intricate ways our universe appears finely calibrated for life.
Imagine standing before a firing squad, with 50 trained marksmen aiming rifles at your heart. You’re certain that this is your last moment, but somehow the bullets all miss and you survive. This could simply be a very lucky coincidence; rerun the event enough times and the squad would be statistically likely to miss a few times. But chances are you would feel perplexed about your survival and want to seek answers about how this happened. This metaphor was put forward by John Leslie to demonstrate Fine-Tuning, and how the existence of life in the universe similarly relies on improbable cosmic conditions, with physical variables seemingly aligning perfectly to enable the evolution of intelligent beings.
While our hospitable universe could just be a fluke, it is only natural for us to try to dig deeper. Over the last few decades, the subject of fine tuning has attracted some of the sharpest minds in physics. By probing the universe’s physical laws and precisely pinning down the values of physical constants, such as the masses of elementary particles, physicists have discovered that surprisingly small variations in these values could have prevented the formation of the components necessary for life in the cosmos — including planets, stars, and galaxies.