Considering that they've been around for more than a century, the Nobel science categories of "physics," "chemistry," and "physiology or medicine" have held up pretty well. But in truth, much of their durability reflects the fact that the committee hasn't worried much about their precise definitions. Nor have they paid much attention to Alfred Nobel's requirement that the prizes go to "those who, during the preceding year, shall have conferred the greatest benefit on mankind." (Care to make a case for the cosmic microwave background, anyone, other than that understanding the universe is inherently "beneficial" to mankind?)
Still, as noted by Doug Natelson, some people will regard this year's physics prize as an injustice, because both the fiber and CCD achievements are primarily engineering, not physics. In fact, both Kao (with processing experts from Corning and Bell Labs) and Boyle and Smith had previously gotten the Draper Prize, which is often described as the "Nobel Prize of Engineering," as had 2000 Physics Nobel Laureate Jack Kilby, one of the inventors of the integrated circuit (William Noyce had died by the time of the Nobel).
The conflation of physics and engineering raises two issues. On the one hand, some physicists will justifiably ask what right the Nobel Committee has to give their prize to people who aren't even doing real physics. I partially agree with Doug that this is an elitist attitude that devalues the real intellectual contributions of engineers. But what Kao did was engineering and materials science, and what Boyle and Smith did was electrical engineering. That doesn't mean it's inferior. It just doesn't happen to be physics.
On the other hand, some engineers will justifiably ask what right the Nobel Committee has to give credit to physics for accomplishments that were made by engineers. This sort of award reinforces the conceit that any transformative technologies must derive from basic science. The reality is that many of the technologies that are changing our world, like google or Wikipedia or eBay or iPhones or even cell-phone cameras, have little need for fundamentally new science--they rest on clever, imaginative, solid engineering.
The other science prizes have an even bigger mismatch, but for them it reflects the excitement and importance of biology, which has no prize of its own. "Physiology or Medicine," for example, has long been dominated by fundamental biology, which more and more relies on molecular biology. This trend leads to a collision with the "Chemistry" prize, which has also been increasingly dominated by molecular biology (not even biochemistry, really). Many prizes might fit equally well in either category, while other exciting fields are left out entirely.
The growing number of category-defying prizes reflects the reality that many exciting discoveries today lie between disciplines or in collaborations between disciplines, as the chemists, physicists, electrical engineers, materials scientists, biologists, and others who contribute to "nanotechnology" can attest. At the same time, some mature areas of physics and chemistry have really solved most of their interesting problems. Their practitioners have valuable skills and insights, but their traditional topics may not be offering the interesting challenges they did in the past. The Nobel categories are only a symptom of a larger issue in academic research that rewards research that fits with centuries-old disciplines.
The Last Ten Physics Nobels (Bold indicates those that are arguably engineering)
- 2009 - Charles K. Kao, Willard S. Boyle, George E. Smith -- "for groundbreaking achievements concerning the transmission of light in fibers for optical communication" and "for the invention of an imaging semiconductor circuit – the CCD sensor"
- 2008 - Yoichiro Nambu, Makoto Kobayashi, Toshihide Maskawa -- "for the discovery of the mechanism of spontaneous broken symmetry in subatomic physics" and "for the discovery of the origin of the broken symmetry which predicts the existence of at least three families of quarks in nature"
- 2007 - Albert Fert, Peter Grünberg -- "for the discovery of Giant Magnetoresistance" [To my mind, this doesn't count as engineering, especially since it omitted Stuart Parkin of IBM, who was critical in making GMR read heads a reality. In fact, as I described in my story on that prize for Physical Review Focus, Fert and Grünberg really were going after fundamental physics.]
- 2006 - John C. Mather, George F. Smoot -- "for their discovery of the blackbody form and anisotropy of the cosmic microwave background radiation"
- 2005 - Roy J. Glauber, John L. Hall, Theodor W. Hänsch -- "for his contribution to the quantum theory of optical coherence" and "for their contributions to the development of laser-based precision spectroscopy, including the optical frequency comb technique" [Again, I count this work as fundamental.]
- 2004 - David J. Gross, H. David Politzer, Frank Wilczek -- "for the discovery of asymptotic freedom in the theory of the strong interaction"
- 2003 - Alexei A. Abrikosov, Vitaly L. Ginzburg, Anthony J. Leggett -- "for pioneering contributions to the theory of superconductors and superfluids"
- 2002 - Raymond Davis Jr., Masatoshi Koshiba, Riccardo Giacconi -- "for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos" and "for pioneering contributions to astrophysics, which have led to the discovery of cosmic X-ray sources"
- 2001 - Eric A. Cornell, Wolfgang Ketterle, Carl E. Wieman -- "for the achievement of Bose-Einstein condensation in dilute gases of alkali atoms, and for early fundamental studies of the properties of the condensates"
- 2000 - Zhores I. Alferov, Herbert Kroemer, Jack S. Kilby -- "for basic work on information and communication technology"
The Last Ten Chemistry Nobels (Bold indicates those that are arguably biology)
- 2009 - Venkatraman Ramakrishnan, Thomas A. Steitz, Ada E. Yonath -- "for studies of the structure and function of the ribosome"
- 2008 - Osamu Shimomura, Martin Chalfie, Roger Y. Tsien -- "for the discovery and development of the green fluorescent protein, GFP"
- 2007 - Gerhard Ertl -- "for his studies of chemical processes on solid surfaces"
- 2006 - Roger D. Kornberg -- "for his studies of the molecular basis of eukaryotic transcription"
- 2005 - Yves Chauvin, Robert H. Grubbs, Richard R. Schrock -- "for the development of the metathesis method in organic synthesis"
- 2004 - Aaron Ciechanover, Avram Hershko, Irwin Rose -- "for the discovery of ubiquitin-mediated protein degradation"
- 2003 - Peter Agre, Roderick MacKinnon -- "for discoveries concerning channels in cell membranes"
- 2002 - John B. Fenn, Koichi Tanaka, Kurt Wüthrich -- "for the development of methods for identification and structure analyses of biological molecules"
- 2001 - William S. Knowles, Ryoji Noyori, K. Barry Sharpless -- "for work on chirally catalysed hydrogenation and oxygenation reactions"
- 2000 - Alan Heeger, Alan G. MacDiarmid, Hideki Shirakawa -- "for the discovery and development of conductive polymers"