Department of Mathematics Cornell University Annual Report 1997Ð98 The image on the cover is taken from a catalogue of several hundred “symmetric tensegrities” developed by Professor Robert Connelly and Allen Back, director of our Instructional Computer Lab. (The whole catalogue can be viewed at http://mathlab.cit.cornell.edu/visualization/tenseg/tenseg.html.) The 24 balls represent points in space placed at the vertices of a truncated cube. The thin dark edges represent “cables,” each connecting a pair of vertices. If two vertices are connected by a cable, then they are not permitted to get further apart. The thick lighter shaded diagonals that lie in the faces of the truncated cube represent “struts.” If two vertices are connected by a strut, then they are not permitted to get closer together. In this example the struts happen to intersect, which is allowed for cables and struts. The examples in the catalogue — including the one represented on the cover — are constructed so that they are “super stable.” This implies that any pair of congurations of the vertices satisfying the cable and strut constraints are congruent. (It turns out that for this structure, each of the six octagonal faces is super stable also.) So if one builds this structure with sticks for the struts and string for the cables, then it will be rigid and hold its shape. The congurations in the catalogue are constructed so that they are “highly” symmetric. By this we mean that there is a congruence of space that permutes all the vertices, and any vertex can be superimposed onto any other by one of those congruences. In the case of the image at hand, all the congruences can be taken to be rotations. Department of Mathematics Annual Report 1997Ð98 Year in Review: Mathematics Instruction and Research Cornell University Þrst among private institutions in undergraduates who later earn Ph.D.s. Ithaca, New York, the home of Cornell University, is located in the heart of the Finger Lakes Region. It offers the cultural activities of a large university and the diversions of a rural environment. Mathematics study at Cornell is a unique experience. The University has managed to foster excellence in research without forsaking the ideals of a liberal education. In many ways, the cohesiveness and rigor of the Mathematics Department is a reßection of the Cornell Tradition. Robert Connelly, chair Department of Mathematics Cornell University Telephone: (607) 255-4013 124 White Hall Fax: (607) 255-7149 Ithaca, NY 14853-7901 e-mail: [email protected] Table of Contents The Year in Review 1997–98..........................................................................1 Support Sta ...........................................................................................2 Graduate Program .....................................................................................3 Undergraduate Program ..............................................................................4 Research and Professional Activities.................................................................4 Faculty Changes .......................................................................................5 New Faculty for 1998–99 ..............................................................................6 Gregery Buzzard; Adam Epstein; Vesselin Gasharov; Anthony Kable; Irena Peeva; Ravi Ramakrishna Gifts .....................................................................................................6 Awards and Honors ....................................................................................6 Bourbaki Lectures; Clark Distinguished Teaching Award; Eleanor Norton York Award; Hutchinson Fellowship; Ithaca High School Senior Prize; Kieval Prize; Sloan Doctoral Dissertation Fellowship Instructional Activities ................................................................................7 Summer Program ......................................................................................7 Curriculum Changes ...................................................................................8 Interdisciplinary Instructional Activity ..............................................................9 Mathematics/Engineering Liaison; Teaching Exchange Relocation Preparations...............................................................................9 Department Needs ....................................................................................10 Support Sta; Operating Budget; Equipment Mathematics Course Enrollment Statistics .......................................................12 Mathematics Department Directory ...............................................................14 Special Programs and Activities ....................................................................16 Spring Concert Series ................................................................................16 Topology Festival .....................................................................................16 Preparing Future Professors .........................................................................17 Mathematics Awareness Week ......................................................................17 Research Experiences for Undergraduates Program ..............................................18 Centers and Institutes................................................................................19 Center for Applied Mathematics; Center for the Foundations of Intelligent Systems; The Field of Statistics Mathematics Library .................................................................................19 Special Instructional Support .......................................................................20 Computer Lab; Mathematics Support Center; Learning Skills Center NSF Undergraduate Faculty Enhancement Workshop............................................21 Mathematics Education..............................................................................21 Cornell/Schools Mathematics Resource Program; Geometry Workshop for Mathematics Teachers; Teacher Education in Agriculture, Mathematics and Science Mathematics Department Endowments ............................................................22 The Colloquium Endowment Fund; The Eleanor Norton York Endowment; The Faculty Book Endowment; The Israel Berstein Memorial Fund; The Logic Endowment; The Robert John Battig Endowment Degrees Granted 1997–98 ...........................................................................24 Department Colloquia ................................................................................28 1997–98 Faculty Publications .......................................................................35 Research Grant Activity ..............................................................................37 The Faculty and their Research .....................................................................38 Faculty Proles.........................................................................................40 Visiting Faculty Program Participants .............................................................73 Sta Proles............................................................................................77 The Year in Review 1997–98 The 1997–98 academic year seemed to pass in the blink Meanwhile, Professor Cli Earle has decided on a pro- of an eye. Beginning as early as possible, we conducted gram of phased retirement at half-time starting July 1, searches for new tenure-track faculty, and we are very 1998. Cli will be teaching fewer courses each year but pleased with our success. Irena Peeva turned down three will continue full-time in his work in mathematics. competing oers to be one of our new assistant profes- sors. Ravi Ramakrishna, whom many will remember Two of our faculty, Professors John Guckenheimer and as an undergraduate here in Mathematics, will also be a Keith Dennis, are ending leaves of absence involving very new assistant professor. As an undergraduate Ravi com- distinguished service to mathematics. John is nishing peted in a Putnam Mathematics Competition as one of his term as president of the Society of Industrial and our team “stars.” Applied Mathematics (SIAM), and Keith is nishing his term as executive editor of Mathematical Reviews. Their We also welcome Vesselin Gasharov, Anthony Kable, excellent accomplishments will benet us all in Mathe- Adam Epstein, and Gregery Buzzard who will join the matics. department as H. C. Wang Assistant Professors in the coming year. In addition, Peter Topping and Vlada The rst year of our experiment with restructuring fresh- Limic have accepted H. C. Wang Assistant Professor- man engineering calculus has been completed. The pri- ships eective July 1999. We will all benet when these mary aim of the experiment is to oer Math 192 dur- bright and exciting colleagues join our faculty, and we ing the fall semesters in small classes of approximately consider ourselves fortunate that they have decided to 25 students. The additional teaching power needed to come to Cornell. We extend a special welcome to all the change this course from the large lecture system to the new members of our department. small class system was provided from a variety of sources. In particular, we received funding for another H. C. We will continue searching for a senior person in mathe- Wang position, four one-semester instructional teaching matical statistics. We may broaden the search to include assistants and additional Cornell faculty to be hired on other areas but plan to ll this