Science Watch Highlights Article by AFOSR-Supported Physicist Published April 10, 2009 By Maria Callier Air Force Office of Scientific Research ARLINGTON, Va. -- The article, "Unified Theory of Coherence and Polarization of Random Electromagnetic Beams," by AFOSR- supported physicist, Dr. Emil Wolf is highlighted in the April 2009 issue of "Science Watch." Though written six years ago, Thomson Reuters' "Science Watch" website (http://sciencewatch.com) identified the article as an "Emerging Research Front" in 2009 in the field of physics."Science Watch" used data from Thomson's, "Essential Science Indicators," (compilation of scientific research statistics, trends, rankings and interviews) to analyze the highly cited paper. In the article, Wolf synthesizes two branches of optics, the "theory of coherence" and the "theory of polarization of light," which were treated as two subjects before the article was written. AFOSR recently had an opportunity to speak with Wolf about his theory and research. The exchange that follows is based on that interview and one conducted and written by Doug Benson in this month's issue of "Science Watch." A: Why has there been so much interest in this article from six years ago? W: It takes some time before scientists become aware of research carried out by others. Also, it is often only after some research applications are demonstrated that interest in it is generated. A: Did you cover any research in the original article that you have recently updated or plan to update in the future? W: Yes, the research reported in this article has been appreciably broadened and new applications have been found in the course of the six years since the article was published. I expect that many applications involving the propagation of light through optical fibers, which are also used for communication, are likely to be forthcoming. A: Describe the theory that is explained in your article. W: Prior to the invention of the laser nearly 50 years ago, light sources would fluctuate when viewed on a short timescale. These fluctuations made it impossible to use light sources, such as a bulb or the sun, for certain applications. Laser light, on the other hand, is coherent and very intense and has more predictable behavior. As a result, it can be used for many purposes, including, for example, operation of computers. A: Did you use any special tools or cutting-edge methods in the research? W: I had to develop some mathematical techniques to broaden the range of applications of the theory. A: How will the research benefit the Air Force? W: It may be too early to give an accurate answer to this question, but there is no doubt the theory can be used to improve precision in guiding as well as communications through the atmosphere, say between an airline pilot and a ground station. A: What were the challenges of your research and how did you meet them? W: It was necessary to find the underlying similarities between two branches of optics that have previously been considered -- incorrectly as it now turns out -- to be independent of each other. I discovered a relationship between them, which led to the formulaton of the new theory. This new theory has opened up many real and potential applications. A: Why is the research important for physicists and laymen? W: Physicists and engineers would profit by paying attention to these developments because they represent advancements and promise wide applications in the understanding of various phenomena involving light.