Why are we here?

Billy the dog when he was young.

Billy and I go for a long walk almost every day. He tries to be around me as much as he can. When I’m at the computer he lies on the floor right behind me. He’s been that way ever since his buddy Boris died suddenly (a stroke) two years ago. He appeared on our driveway in 2016, about a month before I had spinal surgery (August 7). Boris was a dog that was supposedly owned by a lady who lived across the street, but Billy lured him away when we went for walks past his house. We never trained either dog to do anything but sit, and they were never interested in playing fetch. Billy is a very intelligent dog just the same. Boris was very loyal to him (and us).

But that’s not what I want to talk about. No. I want to know, why do we exist? Well, if we didn’t exist, we wouldn’t be here to think about it.

On the other hand, Copernicus (a Polish astronomer from the 1500s) suggested that the Earth revolves around the Sun rather than the Sun revolving around the Earth. This thought started a landslide that has resulted in the opinions of astronomers and cosmologists in the 2020s being a little different. We now hold that not only are we not at the center of the galaxy, much less the Universe, but that in fact the Universe has no center.

Thoughts of this sort are addressed in an article by Tim Andersen published online in Popular Mechanics on May 10, 2024. His conclusions are a little surprising.

Tim Andersen first addresses the tension between the so-called anthropic principle and the Copernican principle. The anthropic principle holds that we are here, i.e. we exist, because the Universe is specially tuned for our existence. All of the basic physical laws and measurements, such as the weight of the neutron and the speed of light, are that way because they make it possible for us to exist.

The Copernican principle demotes us to a not-special place and its mechanism for producing us is natural selection or evolution– notoriously a blind, stochastic process. The principles of natural selection were formulated by Charles Darwin in the 1800s. The beauty of natural selection is that it inevitably produces more and more complex organisms over time, eventually leading to us (and possibly beyond in the future, if we don’t blow ourselves up).

Tim Andersen says this tension can be explained by using the concept of the multiverse. In multiverses, there are infinitely many possible “setups” for the cosmological constants, and we just happen to live in a multiverse that supports human life. There are many multiverse theories, but the one he wants to explore uses what is called the theory of cosmological natural selection. This was first proposed by physicist Lee Smolin in 1992.

In this theory, the appearance of a black hole actually enables the birth of a baby universe. In this new universe, time stands still and the density of matter is infinite at the central point (the only point that exists initially). The point immediately begins to expand, “creating new matter and energy.” (In fact, the infinitely dense matter degenerates to finite density and releases energy from the transition.)

Just as our universe started at a single point as the Big Bang, every black hole starts anew. In the baby universe, black holes appear which are yet new universes, and so on. This is a bit speculative.

Andersen goes off on another tangent: carbon. Carbon monoxide is the second most common molecule in the visible universe, after molecular hydrogen, even more common than water.

In collapsing proto-stellar clouds of space gas formed in supernovae (explosions of large stars), stars form from the hydrogen and the carbon monoxide acts as a coolant, keeping the star from igniting until it is large enough. (Graphite– pure carbon– is used in nuclear reactors to slow down energetic neutrons resulting from fission and thus keep the reactor cool.)

It happens that carbon is also essential for all known life. Our bodies are mostly made of long chains of carbon with hydrogen on the side. So Andersen says that life is a byproduct of the formation of stars, which is a consequence of the universe’s evolution to create more black holes.

This is all a little hard to understand. At the end, Andersen says that it is possible that the Universe itself is alive. It’s like artificial intelligence (AI) in a way, only in a universe, not in a computer. At least it sounds good, better than an old man with a long white beard called G-d.