Thursday, December 11, 2014

Science and sensationalism: The allure of superlatives and bogus metrics

I helped out a colleague of mine today, who was fact-checking a couple of sentences in a story that's going to come out in a large circulation magazine (that shall remain nameless).  The article is about graphene, and in draft form included a sentence along the lines of "Graphene is 1000x better at conducting electricity than copper."  That sounds great and exciting.  It's short, simple, and easy to remember.  Unfortunately, it's just not true unless accompanied by a huge asterisk that links to a page full of qualifications and disclaimers. 

The challenge:  Come up with a replacement that gets the main point across (graphene is a remarkable material) without being a gross distortion or dissolving into scientific jargon. 

My response:  "Graphene is an electrical conductor that rivals copper and silver, and is much lighter and stronger."  At least this is true (or moreso, anyway), though it's longer and doesn't have an easy-to-remember number in it. 

The search for a simple, one-sentence, exclamatory pronouncement can lead science journalists (and university public relations people) down a dangerous path.  Often really great science is simply more complicated than a sound-bite.  Moreover, the complications can be fascinating and important.  It takes a special journalist to recognize this.


9 comments:

Anonymous said...

Yup, and my pet peeve is claims of everything that "may lead to 1000x more powerful processors"... - when the most meaningful word in the phrase is: "may". This happens mostly in engineering and applied science - and mostly the deed of university public relations folks probably eager to drive funding in favor of the university. Failing which, public opinion.

Anonymous said...

By comparing graphene to a bulk material (copper or silver) you immediately lose emphasis on the 2D quality of the material ("thin-filmness", perhaps). Somehow highlighting this in the comparison seems crucial here. KON

Douglas Natelson said...

KON, that's exactly the challenge. As a scientist and educator, I'd love to point out (1) graphene's 2d structure is truly special, leading to charge carriers being able to move impressively long distances before scattering; (2) however, there aren't that many free charge carriers (per volume) in graphene compared to copper, and the carriers in graphene are actually rather slow; (3) the high current density numbers for graphene are impressive but rather bogus, since really good heat-sinking can make lots of nanostructures able to support really large current densities; etc. Not exactly a pithy 1-sentence discussion.

Ted Sanders said...

Great post!

It's hard to get people to make true and careful statements when they have little incentive.

Anonymous said...

just came across this in today's new yorker

"Because of its unique structure, electrons could flow across the lattice unimpeded by other layers, moving with extraordinary speed and freedom. It can carry a thousand times more electricity than copper."

http://www.newyorker.com/magazine/2014/12/22/material-question

Douglas Natelson said...

Anonymous, that's exactly the quote I was talking about. Bleah. So much for my efforts.

Anonymous said...

Well there's something worse than superlatives in that article, something downright wrong
"Engineers have further speeded computers by “doping” silicon: introducing atoms from other elements to squeeze the lattice tighter."

Douglas Natelson said...

Anon@9:37, I think that's referring to working with Si(1-x)Ge(x), which actually does strain the lattice and increase mobility. The imprecision in the language makes the sentence ambiguous of course.

Anonymous said...

Well, putting Ge in Si does not constitute doping in the general parlance - because the carrier concentration does not change.

Though I just looked up Wikipedia(which I guess the author did too), and the definition their would apply to this case:
"for the purpose of modulating its electrical properties".
I disagree though...