Are you a regular reader of this blog? Are you really so brave and generous with your free time? If you are a regular reader, you’re likely scratching your head over a pretty significant question I’ve been ignoring.
I’ve told you that accelerators are big, that they’re hard to build, and that they can get very complex. Why go to all that trouble? What are these behemoths good for? Well, here’s a list. The internet likes lists, right?
- Fundamental particle physics. This is the one everybody thinks of first, especially since the term “atom smasher” is so popular. If you collide two highly energetic beams together (like at CERN, for example), the resulting Einsteinian cataclysm is interesting in all sorts of ways. You can search for new particles, test fundamental physical theories, and study exotic environments. You can ask questions like “why is there matter in the universe?” with a straight face and the expectation of some sort of answer. This all gets very awesome very quickly.
- Basic physics, materials science, biochemistry, etc. We can talk about this more later, but with an accelerator you can create ultra-bright, ultra-fast light pulses. And then you can use those light pulses to study very small, very fast processes. You can look at how proteins behave to study diseases and create new drugs. You can design catalytic processes to enable artificial photosynthesis, because if plants can make fuel from sunlight, why can’t we? There’s a long, long list of things you can do with these “light sources”. In fact, accelerator-based light sources are a HUGE field of research. More accelerators around the world do this kind of thing now than do the above-mentioned fundamental physics research.
- Medicine. I know people who have gotten radiation treatment for various forms of cancer. Typically, doctors will attack a tumor with x-rays. But the problem with x-rays is that they’ll also attack the healthy cells around a tumor. A fascinating alternative is hadron therapy. It turns out that you can “tune” a beam of protons (or neutrons, or both) so that they deliver energy to a very specific target volume. You can use beams of protons (or neutrons, or carbon atoms, or whatever) to attack tumors without so much damage to the surrounding, healthy tissue. And where do those hadron beams come from? Accelerators, of course! I assert that this is cool.
- Safer nuclear power. Nuclear power is generally pretty safe, but last year we all got an object lesson in its potential problems. I know people working on accelerator-driven nuclear reactors that overcome some of these problems. If you build a reactor right, you can control the fission process with an accelerator. No beam, no fission! This makes things much safer — you don’t have to worry anymore about meltdown. “Aha”, you’re saying, “but what about nuclear waste?” Well, it turns out that you can “burn” (really, transmute) nuclear waste with accelerators too. Really. I’m not kidding. Here’s a video, shot at Fermilab:
There’s another hugely important use for accelerators that’s harder to talk about in concrete terms. They’re hard to build, right? And they require cutting-edge technology? The technology that’s developed for accelerators often makes its way into the private sector, and from there into everyday life. Do you know anybody who has had an MRI scan? The magnet technology in MRI machines was first developed for bending particle beams in accelerators.
Not good enough? Maybe you’ve never had an MRI? Well, have you ever used this “world wide web” thing?
Seriously. The vast architecture of the internet was developed by many people over a long time. But the internet that you interact with daily is based on the work of a few people who worked at CERN. They tried to figure out a better way to share their data, and the result was the World Wide Web. You know how you type http://danielbowring.net into your browser in order to look at my site? That’s the result of some people at an accelerator laboratory, trying to solve an interesting problem.
A long post today, I know. I tried to pad it out with youtube videos, so it wouldn’t just be a vast ocean of text. But hopefully, at the end, you have more questions now than you did when you started. I encourage you to ask these questions in the comments section! At the very least, stay tuned. I plan to dig down deeper into these ideas (and talk about other uses for accelerators that I didn’t have room for here) in future posts.