Wednesday, December 14, 2011

Harmful errors in science journalism

Popular science reporting is incredibly important for making current research known to the lay public in a concise and simplified manner. It often acts as the go-between for channeling information from scientists and engineers to the people who could benefit from the research. Unfortunately, translating new concepts from the jargon of specialists to untrained individuals poses challenges, and often the science in these articles is erroneous. This is a rather well-known problem and the reason why I read such articles with skepticism.

Two different friends sent me this article recently from MIT News reporting on the development of a camera for generating "Trillion-frame-per-second video." Armed with my usual dose of skepticism, I glanced quickly through it and the accompanying YouTube video. I think the significance of the work is a bit overstated [1], but the article sufficiently addresses its limitations and applications. Unfortunately, in describing the operation of a streak camera, the author Larry Hardesty notes that
"The aperture of the streak camera is a narrow slit. Particles of light — photons — enter the camera through the slit and pass through an electric field that deflects them in a direction perpendicular to the slit. Because the electric field is changing very rapidly, it deflects late-arriving photons more than it does early-arriving ones."
Electric fields do not deflect photons. Electric fields deflect moving electrons. What is likely happening inside the camera is that photons scattered from the bottle impinge upon a phosphor screen, which in turn ejects electrons. The electrons in turn are deflected by the time-varying field within the camera to different points on the detector. Electric fields can be modulated with RF equipment up to a few hundred GHz, which roughly corresponds to a few tenths of a trillion oscillations of the field per-second. I believe that this is how the noted number was obtained.

So what's the big deal? The point of the article, after all, is to inform a general audience about a newly developed camera—the details of its operation should not matter. Here are a few reasons why errors such as these are harmful:
  1. Many people who read these types of articles are students or young people who aspire to be scientists. To provide incorrect information hurts their education by establishing false ideas within their minds.
  2. It's dishonest. Whether the author knew he had made a mistake or not, the article should have been reviewed by one of the scientists before its publication [2]. Eventually, people could learn to associate dishonesty with science and this is clearly undesirable.
  3. It's distracting and draws attention away from the article's main message. I'll admit that I had made up my mind that the research was flawed after I saw the error. Only a second, careful reading revealed that nothing about the research was in error.
This article is just a minor example of an all-too-common problem with science journalism. Unfortunately, I've seen much worse mistakes. I wonder how many times I've been fooled by a false proposition in a piece of reporting.

[1] It images processes that are stationary over at least one hour in time. For example, it can not image a turtle that walks through its field of view. Dr. Velten's quote in the beginning of the article might be placed in better context by noting that while few things are too fast for the camera, many things are too slow for it.

[2] I was once quoted several times in an article about my research that I had not realized had been published until I chanced upon it while Googling my name. I didn't find it until nine months after it appeared in print. I received no word from the author what-so-ever that it had appeared in the Orlando Sentinel, and was misinterpreted as having stated that our work existed only in theory. If the author had asked me to review the article prior to its publication, this error would not have been made.