Life in the Sun

April 8th, 2000

The title of this essay may seem familiar, but in fact I discuss not what it is like to live in the open sunlight, but the likelihood that there are living systems inside our sun.

This hypothesis surely startles; as much as we may pride ourselves in our broad-mindedness about the possibilities of extraterrestrial life, the concept of living systems inside a star seems wildly outlandish (out-terra-ish?)

But before you dismiss this essay as complete rubbish, I ask you to consider one fundamental truth: life is, in essence, a manifestation of negentropy. For those of you who don’t keep your thermodynamics textbook on your bedstand, entropy is a thermodynamic thingamabob. It’s like "energy" or "matter" or "force": a basic physical property. What makes it difficult for most people to understand is that it has no tangible expression. You can feel mass in your hand, sunlight energy on your face, or force against your fingertip. But entropy is intangible: it’s disorderliness. Its opposite, negentropy, is orderliness. While you can’t directly sense these physical quantities, you can certainly conceive of them. Strong, bright sunlight is high in negentropy; a grey, featureless shadow is low in negentropy. Marbles stacked in neat rows have high negentropy; marbles lying around in a messy way have low negentropy. 135 pounds of carbon, hydrogen, oxygen, and nitrogen arranged just right make up a high-negentropy Chris Crawford; put him through an osterizer and you’ve got 135 pounds of low-negentropy bloody mess. That’s the key: the only difference between 135 pounds of hydrocarbons and Chris Crawford is the extremely high negentropy of the latter. And that’s the whole point about life: it’s not energy, it’s not matter, it’s a highly organized arrangement of matter -- matter graced with lots of negentropy.

Where does all this negentropy come from? The sun. All that sunlight shining on all those photosynthetic cells allows them to convert the negentropy into a chemical form: specially organized molecules. A lot of people get confused because sunlight is, after all, just energy, and so they think that it’s the energy that’s so important. Not! If you think that the energy of sunlight is what’s important, then just put that plant leaf on the surface of the sun, where it’ll get oodles and oodles (well, at least 4.3 x 10**18) photons of sunlight. That won’t make it grow better. What makes it all work is the fact that there’s night, or rather then difference between day and night. That difference is the orderliness that makes life work. If there were no night, the earth’s surface would heat up, there’d be photons all over the place, and plants wouldn’t be able to take advantage of it. The big trick is that 4,000-degree photons hit a leaf at 300-degrees (Kelvin). It’s that temperature difference that makes life possible. Everything else -- cell membranes, amino acids, DNA, all that stuff -- is just engineering details.

Indeed, when you start thinking about it this way, your perspective changes. Basically, we’ve got the earth’s surface here with the sun pouring scads of negentropy (orderliness) all over it -- and you think that it’ll just sit there and bounce all that negentropy off? Wouldn’t you think that just a tiny fraction of that orderliness might actually rub off on the planet itself?

In this way of thinking, we start our search for extraterrestrial life by asking, "where in the universe are there strong flows of negentropy?" Once we’ve identified likely candidates, we then start to inquire into petty details like availability of liquid phase solvents, appropriate chemicals and temperatures, etc.

The first place to start is inside a star. If we get all our negentropy from the sun, then obviously, the sun has lots and lots of the stuff to start with. Of course, there are some problems. The surface of the sun is obviously the worst place in the universe to look for life: its entropy flow is exactly the reverse of what we get on the surface of the earth. Instead of high-temperature photons hitting a low-temperature surface, we’ve got low-temperature photons departing from a high-temperature surface. This is obviously not the place to look for life.

But, deep inside the sun, there’s another place that might just support life. It’s the transition zone between the radiative layer and the convective layer. You’ve got lots of negentropy pouring out of the core and piling up in this transition zone, in much the same way that those photons hit the earth’s surface. The biggest difference is the intensity of the phenomenon: the negentropy flux is at least 10,000 times higher than on earth! Now THERE’S a source of negentropy to work with!

All we need now are some of those engineering details to make it all work. Briefly put, we need a sufficiently complicated set of physical interactions that might permit the negentropy to be channeled. Obviously, those will not be chemical reactions. But there’s another possibility: magnetohydrodynamic behavior. At this point, I run the risk of Frankensteinean mysticism: stitch the right parts together and then zap them with that mysterious stuff, electricity (or in this case, MHD), and they’ll come alive. And in fact, I must confess that I cannot demonstrate that magnetohydrodynamic interactions are sufficient to the task. All I can say here is that, first, magnetohydrodynamics is really complicated stuff, capable of doing all sorts of squirrelly things. (This is one reason why we still don’t have fusion power working after all these years -- the damn plasma starts interacting with the enclosing magnetic field and things go absolutely crazy.) Is MHD as complicated as organic chemistry? I doubt it -- but perhaps we don’t need the combinatorial richness that organic chemistry gives us. Perhaps we’ve got so much negentropy flux that we can still get living systems based on simpler interactions.

Second, the sun is a big place, much bigger than the earth, so the laboratory of random combinations that is needed to stumble upon the correct pattern of magnetic fields is much, much bigger than the laboratory on this planet that eventually produced life. Furthermore, that boundary between the radiative zone and the convective zone has been in roughly its present configuration for longer than the earth has been around. So there’s been plenty of time for that lab to come up with something interesting.

Third, we know that the sun has lots of magnetic fields in it, and they behave in really perplexing ways. The stuff is there, and it’s certainly behaving in lots of weird ways. I wonder if the magnetic fields we’re seeing on the sun aren’t in some way related to life forms deep inside? Perhaps we shouldn’t think in terms of life forms in the plural -- after all, there are no good sources of well-defined membranes in an MHD environment. Perhaps we should think in terms of one gigantic life form encompassing the entire spherical shell of the transition zone. If so, the magnetic fields that we see on the surface might be indirect manifestations of its metabolism. Which of course means that sunspots are --you guessed it -- pimples.