Twenty-first century science
One often hears biologists say that biology is the “physics of the 21st century.” When they say this, I think the main motive is to indicate that great scientific advances will be coming out of biology in the next century.
I’ve never actually heard a biologist say this, perhaps because I know relatively few biologists. I have heard several physicists say it, presumably that class of physicist who wishes they went into molecular biology, or perhaps made billions in the .com boom.
My own opinion is the physics is going to be the physics of the twenty-first century.
I have two broad sets of reasons. First, there are a bundle of really important fundamental questions that we don’t know the answer to:
- How can quantum mechanics and gravity be put into a single theory, preferably one integrating the usual standard model of particle physics?
- What’s up with quantum mechanics and measurement? The fact that we don’t properly understand our most successful scientific theory always seems to me like something of an embarrassment.
- How did our Universe start? How will it end? What is its structure?
- There are many other puzzles – dark matter, the cosmological constant, the Pioneer anomaly, and others – which we don’t understand. It’s possible and maybe even probable that some of these are unimportant. Still, it seems pretty likely that one or more of these is the tip of a really big iceberg.
Progress on any of these is likely to come from within physics; it will certainly affect physics, and if past history is any guide, it will probably profoundly affect the rest of science and technology as well. Of course, it may take decades to make real progress on these problems, and I suspect this is where some of the attitude Dave refers to comes from – a feeling that the grass is greener on the biological side.
My second set of reasons are more applied, although I suspect they will greatly impact the fundamental questions as well:
- Nanotech. Yes, there’s lots of hype. My guess is that in the short run, this will turn out to have been over-the-top, but in the long run, it’ll seem incredibly restrained. A self-replicating assembler, even one with extremely limited capabilities, is likely to have astonishing consequences.
- Complex quantum systems. I think we’ll see a revolution as people assimilate the idea that whole new types of complexity can arise in quantum systems, going entirely beyond what is possible in conventional classical systems. My guess is that phenomena like superconductivity and the fractional quantum Hall effect are the tip of the iceberg.
- Quantum nanoscience and quantum information. These are really two sides of the same coin: leveraging the power of complex quantum systems to accomplish tasks (either material tasks, or information processing) impossible or impractical in the classical world.
I could, of course, easily be wrong about any of these things, and there’s undoubtedly a lot that I’m missing. But these are all reasons why I’m very optimistic about the role physics will play in twenty-first century science.