You may be familiar with the “arrow of time,” but did you know there may be another?
Dr. Robert Hazen, an earth and planetary scientist at the Carnegie Science Laboratory in Washington, DC, thinks a single arrow of time may be too restrictive. The second arrow, which he calls “the law of increasing functional information,” takes evolution into account. Specifically, Hazen explains that evolution seems to involve not only time, but also function and purpose.
Consider a coffee cup: it works best for holding coffee, but it could also work as a paperweight and wouldn’t work well at all as a screwdriver. Hazen explains that the universe seems to be using a similar way of developing not just biology, but other complex systems throughout the universe.
This idea suggests that as the universe ages and expands, it becomes more organized and functional, almost contradicting theories surrounding growing cosmological perturbations. Hazen suggests that these two “arrows”—one entropy and the other organized information—could very well run side by side. If true, this theory could be groundbreaking in the way we perceive time, evolution, and the very fabric of reality.
Robert Hazen: I have a confession to make here. I have to be honest. We could be wrong. We could be spectacularly wrong. But it’s also possible that science is missing a deep truth about the universe. We have these 10 or so laws of nature, only one of which currently has an arrow of time. That’s the second law of thermodynamics, the increase in entropy—it’s disorder; it’s a decline.
We all age. We all die. But the second law does not explain why things evolve; why life emerges from non-life. You look around and see flowers blooming and trees blooming and birds singing. All of these things seem to contradict the idea of ​​clutter. In fact, it is a kind of arrangement of nature.
So let me tell you what we think: We think there is a missing law, a second arrow of time that describes this increase in order, and we think it has to do with the increase in information. So there are two options. We can only be wrong. We could be terribly, dramatically wrong. But I think if we’re wrong, we’re wrong in a very interesting way. And I think if we’re right, it’s extremely important.
I’m Bob Hazen. I am a scientist at Carnegie Science’s Earth and Planetary Laboratory in Washington, DC doing mineralogy and astrobiology. I love science. We think the second arrow of time is missing for some reason. And this arrow has to do with the increase of information, the increase of order, the increase of patterning, which goes side by side with the arrow of increasing disorder and increasing chaos, entropy.
At the heart of everything we’ve thought about in terms of the missing law is evolution. When I say the word “evolution” you immediately think of Darwin, but this idea of ​​selection goes much, much further than Darwin and life. This is true for the evolution of atoms. It applies to the evolution of minerals. It refers to the evolution of planets and atmospheres and oceans. Evolution we see as the increase in diversity, patterning, complexity of systems over time.
And so the question is, “Well, what is evolution?” Evolution is simply selection for function. And this applies to any kind of system. Now, in life, you select organisms that can survive long enough to reproduce and have offspring that pass on their traits. That’s what Darwin said, and that’s one very important example of functional selection. But in the mineral world, you choose organizations, assemblies, structures of atoms that persist, that can last for billions of years even in new environments.
They won’t fall apart. They don’t dissolve. They don’t weather. It is very similar to biological evolution, but differs in details. We think there is a law missing here – it is the law of evolution. And if there is a law, it must be quantitative. It must have a metric. You have to be able to measure something. And what we’ve focused on is a fascinating concept of information, but not just information in general, something called “functional information.”
I’ll see if I can explain it to you because it took me a while to figure it out myself. Imagine a system, an evolving system, that has the potential to form a vast number of different configurations. Let’s say it’s atoms to make minerals and you have dozens of different mineral-forming elements and they can arrange themselves in different ways. And 99.99999999 – I could go on – percent of these configurations will not work. They will fall apart. It will never be created. A small, tiny fraction makes up a stable mineral, and you end up with a few stable minerals and a lot of scum.
Now all you have to do is think about that fraction. If one of the hundred trillion, trillion, trillion, trillion possibilities is stable, then you can represent that fraction as information. And because it’s such a tiny, tiny fraction, you need a lot of information to do that – that’s functional information. Evolution is simply an increase in functional information, because as you select for better and better results, you select minerals that are more and more stable. You select for living things that can swim. They can fly. They can see.
You need more information, and each step of the evolutionary ladder leads you to increasing functional information. So our law, our missing law, the second arrow of time is called ‘The Law of Increasing Functional Information.’ And that’s the parallel arrow of time that we think is out there and we want to understand. The idea of ​​increasing functional information has a really deep meaning. Think about the functional information of a cup of coffee; maybe you’re holding one right now.
You have lots of atoms, and those atoms can be in trillions trillions trillions of different configurations, but only a tiny fraction of those configurations make up a cup of coffee. Now imagine a cup of coffee as a paperweight. I know you used a coffee mug as a paperweight. We all have and it’s pretty good, but you can make a better paperweight. And a cup of coffee makes a terrible screwdriver. Think about it: We say that a cup of coffee is worth a cup of coffee. It has some value as a paperweight, but no value as a screwdriver – that’s contextual.
So that’s why the second arrow of time is difficult for science because it says that there is something in the natural world that is not absolute. It’s contextual. It depends on what your purpose is. It depends on what function you have. If this is true, we are saying that there is something in the universe that increases order, it increases complexity, and it doesn’t do it in a random way. Selects for function. And if so, if you’re picking a feature, does it almost seem like there’s a — can I use the word “purpose?”
Do minerals have a purpose? Do atmospheres have a purpose? Does life have any meaning? To me, there is something real there and the old way of thinking about a single arrow of time doesn’t ring true to me anymore.