The opposite of entropy is order – the maintaining an unlikely state like an unbroken egg. Indeed, the entire earth is a complex web of order that somehow maintains itself despite changes like weather and errant asteroids. At first, physics argued that the earth is as a local anomaly, a random accident that bucks the universal trend, because:
“… . eventually all these over densities will be ironed out and the Universe will be left featureless and lifeless forever, it seems” (Barrow, 2007)(p191).
Yet the cosmos is also ordered, as planets orbit stars that orbit galaxies that orbit super-clusters, where each order depends on the one above. Life on earth is only possible because the sun keeps its planets in order and the solar system is only possible because the galaxy keeps its stars in order. It isn’t just the earth that presents a “local anomaly” and thanks to this cosmic order, life evolved on earth.
A better answer was needed so some physicists now suggest that the big bang was very ordered:
“The ultimate source of order, of low entropy, must be the big bang itself. … The egg splatters rather than unsplatters because it is … the drive toward higher entropy … initiated by the extraordinarily low entropy state with which the universe began.” (Greene, 2004) p173-174
This is physics speak that the universe began very ordered and we are only half-way through its “grand devolution”, so life is still possible. In this reverse logic, the initial chaos had to be very ordered because the second law is true, but that the current cosmic order devolved from a very ordered initial chaos makes no sense at all.
And life isn’t just any old order but a self-replicating order, and the discovery that it might spread between planets radically changes the probabilities. Panspermia is the theory that bacteria can hitch a ride on an asteroid, meteoroid or comet to travel the space between planets, based on the discovery that bacteria can survive space, as bacteria in boxes outside the International Space Station were revived after over a year in space. Under harsh conditions, some bacteria form spores that are metabolically dead but can return to life under the right conditions, even after millions of years. That life can evolve on a planet that is temporarily suited then spread to another where it is permanently so significantly increases its probability, e.g. perhaps bacteria evolved on Mars then colonized Earth. The evidence is still open, but suggests that thanks to bacterial “colonists”, millions of planets in our galaxy may have some form of primitive life. Clearly a galaxy that might be teeming with life isn’t what the second law predicts after 14 billion years of constantly increasing disorder.
So the question remains, if the universe is constantly devolving, how did life evolve? We see order all around us, in our lives, in nature and in the cosmos, so we now consider the alternative that the second law isn’t the only universal principle at play.