Wednesday, July 06, 2011

An unfortunate name for a cool tool: The Radioactive Orchestra

It’s a musical “Quantum Mechanics for Dummies.” Only it’s not. It’s just musical. And what a pity.

[The Radioactive Orchestra web site.]

From the Kärnkraftsäkerhet och Utbildning (Nuclear Safety and Training Ltd.) in Sweden comes the Radioactive Orchestra Рan online music mixer that plays atomic nuclei instead of instruments. (Not only can you hear what a decaying nucleus might sound like, but you can create a sweet beat with it too!)

The only problem: It’s supposed to make radiation and atoms easily understandable and it doesn't. Anyone could play with it and say “Oh, that’s an artist’s interpretation of what carbon might sound like!” and he’d be right, but he still wouldn’t understand atoms any better.

There are two reasons for this, chief among them is the creators’ failure to explain well what the orchestra shows. It’s a nifty tool that - no thanks to the few thin lines in a pop-up “About” section - fails to live up to its own expectations. At our office, it took a retired physics professor, a former engineer and two science writers several days to figure out. What about the average person?

The orchestra’s goal, the creators say, is “to inspire everyone to learn natural science by making it playful and beautiful.” Playful and beautiful it may be, but unfortunately, it does nothing more than entertain. That’s a long way from inspiring.

A short explanation, though, would do the orchestra a lot of good. A refresher on the atomic nucleus – the hub at the center of an atom - is a good place to start:

Elements on the periodic table are defined by the number of protons in their atomic nucleus. (This number is called an element's atomic number.) Helium, for example has two protons in its nucleus, making it the second element on the periodic table (with an atomic number of two).

For a given element, the amount of protons in a nucleus never changes. If a nucleus has three protons, it’s lithium; one and it's hydrogen. Two protons in a nucleus always equals helium.

In addition to protons, an atom's nucleus can also contain neutrons. While protons define an element, neutrons define an isotope of an element. The combination of protons and neutrons in a nucleus is known as the atomic mass.

If helium has an atomic mass of three that means it has one neutron: Two protons plus one neutron equals an atomic mass of three. This would be written as "helium-3" and is known as an isotope. Helium-4 is another isotope of helium. It has two neutrons. (Two protons plus two neutrons equals an atomic mass of four.)

Don’t worry too much about isotopes though. All you really need to know is that they are variants of elements. Now, on to the Radioactive Orchestra.

Nuclei sometimes get excited. (This could be done by bombarding them with a muon beam in a laboratory, for example.) The protons and neutrons bounce around like a bag of marbles on a shaking table. Nuclei like to be calm, however. Excited nuclei want to get back to their unexcited – or ground – state. To do that, they shed energy in the form of photons – packets of light that behave both like waves and particles. This shedding is known as “decay.”

As the nucleus relaxes – let’s say – it sheds photons in a pre-arranged sequence, like notes being played in a chord. Once it sheds the first photon – or plays the first note– it has to keep shedding photons from that sequence. It has to keep playing notes from the same chord. For each element, there are several chords its atoms can choose to play as they decay. This is what is seen on the Radioactive Orchestra website.

Pick an element and play it. Look closely at the nucleus: The protons and neutrons (the red and blue spheres) are bouncing around. They’re excited. Suddenly, they release a little energy. We see this in the form of a squiggly colored line. The nucleus has ejected a photon – a little packet of light. We see on the right that the first note has been chosen, represented by a blue bar.

Now, the nucleus is going to continue emitting photons until it gets back to its ground state – its preferred energy level. It emits photons along a set decay sequence – playing specific notes in the chord dictated by the first note. We see this as the blue bars. The orchestra continues to play through every possible chord – every potential decay sequence– that a given nucleus can go through and then repeats itself. Enterprising DJs turn these pings into music.

[Extreme radioactive orchestration. By DJ Axel Boman.]

It’s a novel musical (and visual) representation of quantum mechanics, but it has two main flaws that prevent it from reaching its potential.

First is that lackluster explanation of what is going on. I’ll give the creators the benefit of the doubt, though, because translating a scientific explanation into English isn’t exactly easy. Even so, their orchestra targets the everyday man, and while John Smith may be able to appreciate a cool atomic beat, he won’t get anything out of the explanation. A semester of quantum mechanics would be needed to have even a basic grasp of what they’re saying.

The other big flaw is one of terminology. The title “Radioactive Orchestra” is misleading, chiefly the word “radioactive” which evokes thoughts of alpha and beta particles and the high-energy gamma rays that are emitted by radioactive elements trying to stabilize themselves. This emission is also known as “decay.”

There are two types of decay, then, when it comes to atoms. The one represented by the Radioactive Orchestra happens when an energized nucleus decays to a ground-state nucleus. The byproduct of this decay is low-energy photons (and an imaginary electronic ping).

Radioactive decay, on the other hand, happens when a radioactive element gains or loses a proton, and changes its personality, becoming a new element. This is the kind of decay that can harm humans and animals and not the decay depicted by the orchestra. Unfortunately, the authors’ explanation doesn’t make this clear.

Calling the web site the “Radioactive Orchestra” implies that all of the decay shown is this second type of decay – the one that changes what an element is. Since there’s no indication on the website of any of the musical performers changing their identities, we know this is not what they are depicting.

Additionally, while some of the isotopes on this chart are radioactive, not all are. The only possible explanation for calling the orchestra radioactive is that when a nucleus emits a photon, it is emitting radiation (albeit a small amount) because photons are light and light is radiation. But that isn’t enough. They would have done better to call it the “Elemental Orchestra” or the “Excited Isotope Music Box.”

1 comment:

  1. Hey, I was wondering if you could tell me something more about this site. At school, I've got to make a project about it, and you guys seem to know quite a lot about it. The project is to make a brochure about the site, but I didn't understand the site quite well... Could you help me?

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