Built on Facts

I am sick. Sore throat, sinus congestion, muscle soreness, all the hallmarks of what I hope is just the common cold.

Barring more serious failures of the body itself, illness is usually caused by bacteria trying to eat you, or viruses trying to program you to stop all that pesky “life” business and get to the real work or producing more viruses.

If they haven’t developed antibiotic resistance, bacteria are usually more or less killable. They’re living things, so if you saturate them with enough chemicals which interfere with their metabolism you can kill them or at least stop them from reproducing. Viruses are trickier. They’re not alive, at least not in any usual sense of the word. They’re little DNA or RNA carrying packages which simply latch onto your cells and make them do the work of making new viruses. With no metabolism to disrupt, there’s not really any good way to kill them chemically. You can shred them to little bitty disassociated pieces with something like bleach, but this is not a viable treatment for viruses already in residence in your body. Interferon is better, but generally not even remotely approaching a cure.

Here, straight from the Wikipedia article, is a picture of an adenovirus.  Two, actually:

You might notice it’s a very regular geometric shape. This particular bundle of viral joy is an icosahedron, itself made up of roughly spherical globs of protein capsids which form the external structure. Hit it with a tiny tiny hammer and it will vibrate just like anything else, from bells to wine glasses to the Tacoma Narrows Bridge. What laymen usually call natural or resonant frequencies of an object are usually called normal modes, eigenmodes, or something similar by physicists.

Dump enough energy into an object vibrating at resonance and you may well be able to shake it apart. It happened to that bridge at Tacoma, and it happens to wine glasses in science demonstrations all the time. Here, for instance.

You can’t do this to a virus with sound. The resonant frequency of a virus is way, way too high to even think about trying to use sound. But how about light? Its frequency can be pretty much as high as we want. The trick would be to figure out just what the resonant frequencies of the virus particles were. You can’t literally hit one with a hammer to see how it vibrates and so the only remaining option is to do the hardcore computational physics to calculate the normal modes from scratch.  For a bumpy system where atomic-level resolution is important this is very, very difficult.

Eric Dykeman and Otto Sankey have developed a pretty good system for doing this, published in PRL 100, 028101 (2008).  They’ve successfully determined the normal modes for several viruses, and that’s the first step to selectively vibrating them to pieces with lasers.  There’s a lot of technical difficulties to be overcome, and it may never become a practical reality.

But as I sit here with a box of tissues and a bottle of Day-Quil, here’s hoping it does.