Science (vol. 306, No. 5700, November 2004)


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THIS WEEK IN edited by Stella Hurtley and Phil Szuromi CREDITS: (TOP TO BOTTOM) ZHANG ET AL.; FORGET Toward Optical Metamaterials suggest that meridional mixing occurs, which is contrary to Metamaterials that are engineered to exhibit negative indices of the idea that separate vortices of material, particularly at the refraction can provide a number of advantages in optics, such as poles, are driven by planetary rotation. the fabrication of a “perfect” lens, and much effort is being directed to push the Before the Divide with the Nanotube Yarns and Forests frequencies at which negative indices can Great Apes Spinning fibers to make stronger yarns be achieved into the optical regime. Using and ropes is an old technology. By lookThe group that includes humans and great nanofabrication techniques to shrink the ing at the fundamentals of this process apes is thought to have diverged from dimensions of gold nanostructures makand scaling them down to fibers other apes (such as gibbons) in the Middle ing up the metamaterial, Linden et al. with nanometer-sized diameters, Zhang Miocene, about 10 to 15 million years (p. 1351) show that the magnetic reet al. (p. 1358) have developed a ago. Few relatively complete fossils are sponse can be raised to 100 terahertz. On technique to spin available from this time; all the theoretical side, Pendry (p. 1353) incarbon nanotube are thought to be related to troduces an alternate route to the design yarns from mats of later great apes from Eurasia. of metamaterials exhibiting negative refibers. The twisted Moyà-Solà et al. (p. 1339; see fraction that may prove easier to prepare yarns can be infilthe news story by Culotta) than the present structures, which are trated with a polyhave recovered a remarkably based on tuning the electric and magnetic mer to improve preserved fossil of a new ape response. The proposed structure relies on their str