Infinite Worlds

Giordano Bruno would have been proud. In 1600, the Italian monk was burned at the stake at Piazza dei Fiori in central Rome for, among some very serious theological offenses (e.g. Mary wasn't a virgin, the Holy Trinity was a scam, etc.), stating that every star in the sky was a sun and that each one of them had its own court of planets. Bruno even put forward the notion that, just like our own planet, these worlds would have living beings and plants. Well, a couple of weeks ago a team at the Southern European Observatory announced the discovery of another 32 extrasolar planets, putting the present count at over 400!

This is exciting science, changing our collective worldview. Yes, many have suspected that there were planets surrounding stars, even in ancient Greece. Why should our solar system be so special? The existence of planets is actually a natural consequence of how we understand stars are born, from the collapse of huge clouds of hydrogen, sprinkled with some (or many, it depends) of the elements of the periodic table. But one thing is to think planets are out here; another is to actually detect them. In science, seeing is believing.

If the Milky Way alone has about 300 billion stars and most of these stars have planets (and some will also have moons), we are talking over a trillion worlds in our own galaxy. A mind boggling number of worlds, each of them different: different chemical composition, may or not have magnetic fields, may or not have an atmosphere, moons, liquid water, frozen water, axial tilt... There is an emerging field of astronomy called "comparative planetology". To learn about many worlds we need to compare them, how they were formed, what's their chemical composition, their distance from their parent star, mass, radius, etc.

Of course, the question in everyone's mind is how common "other earths" are. Are there other worlds with similar characteristics to our own? If so, would life have developed there as it did here? What kind of life would that be? Simple? Complex? We don't know. And, in fact, opinions vary wildly, although we can group them roughly in two camps: the astronomers and the biologists. (Of course, as with any generalization, this one fails. But it's practical.) The astronomers look at the big numbers, the trillions of worlds and claim that, yes, life is out there, and we are just one of an enormous crowd of "typical observers". So, they believe that not just life but intelligent life is all over the place. The biologists are more skeptical. Look at the story of life on Earth, they claim, and you will see that things are more complicated than that. First, for about 2 billions years, life here was pretty simple, unicellular blobs called prokaryotic cells. Only in the last 500 million years or so things got more interesting, and life became multicellular. How can we be sure that complex life will evolve elsewhere? Does evolution necessarily lead to complexity? (And here is a tease for my fellow bloggers in the bio field...) I'd say not. Natural selection has no grand plan toward complex life forms. Whoever fits well into the current environmental conditions will do better. If we are here, it's because of a series of fluke accidents. In this case, we are pretty rare. And precious. Not sure Bruno would have liked this too much.

Why Kepler?

This blog is a new group effort, a collaboration by a team of scientists and science journalists who want think out loud about a new vision of Science and its role in human culture. Each of us has our own take on what that means and I will let my colleagues explain their own perspective for themselves but today I just wanted to riff on the importance of Johannes Kepler for me in thinking about this project.

We live in an era that is saturated by the fruits and poisons of Science. There can be no doubt have the boons that the scientific world-view has brought to our now global culture (it is what allowed that global culture to form in the first place).

Science has allowed more people to live longer more healthy lives and has increased the material well-being of many. It has been an integral part of ever widening program of freedom of inquiry and intellectual discourse that has helped shaped the modern world as one with a promise (at least) of progressive and egalitarian standards. At the same time, and you don’t need me to tell you this, it has played an integral role in the creation of the very real and very dangerous challenges we face heading deeper into the 21^st century. Every generation tends to think it is on the cutting edge of history but its hard to not believe that those human beings alive today really will be present for a cusp - a change - in the trajectory of the species for better or worse.

So what does this have to do with Kepler? To answer that question, it's best to turn to another eminent scientist a little closer to our era. Wolfgang Pauli was a Noble prize winning scientist who was a key player in the foundations of modern quantum theory. He was a hard-nosed theoretical physicist who was known as the conscience of his field (he is also the originator of the worst insult in science – “not even wrong”). In the 1950s Pauli wrote an essay on Kepler in which he recognized the renaissance science as one who stood between two worlds – worlds which Pauli thought might need to be bridged again.

Throughout his intense mathematical work on the shape of planetary orbits, Keller never stopped thinking in terms of the symbolic. He valued the Copernican Model because the Sun was the rightful “ruler” of the heavens. Platonic forms embodied mathematical harmonies and so the world must be constructed in the likeness. He was a scientist who respected data as the final word in scientific inquiry but was convinced that the world spoke to us in both number and meaning. For Wolfgang Pauli whose vivid dreams often spoke in the language of mathematical physics, Kepler’s instance on the importance of symbolic meanings that rose above specific scientific investigations held a kind promise of recovery. Pauli knew Kepler’s 17^th century worldview could not and should not be recovered (the platonic solids don’t have anything to do with planetary orbits after all). But what mattered for Pauli was the recognition that science - its metaphors, symbols and narratives - carry meaning beyond mere results. They can speak beyond just science practice because the have a broader human context

And that is where we begin.

There are those who say science shows us a Universe without meaning. I say that is a tragically narrow perspective. Science shows us a universe full of meaning because we create it, we imagine it, we respond to the world as it reveals itself to us. In that way we create meanings for the Universe and we do so in the ways that are innate to our species – through metaphor, symbol and narrative.

It is true that science as a discipline needed to mature past the symbolic. The problem came science is only way to express our humanity. The entirety of human culture could not fully leave the realm of meaning behind. It always reappears in our art, our music, our politics and our longing for a sense of what is sacred in our lived experience. The trick now will be to understand how a human culture saturated with Science can find the proper context for the symbolic, for the deeply felt, character of life that also expresses through Science and the cultures broad contact with Science.

Somehow we must integrate our manifold ways of known without losing our way. The trick now is to set science into its proper context.

Adam Frank