Virginia Ragsdale

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Virginia Ragsdale (born December 13, 1870 in Jamestown , North Carolina , † June 4, 1945 ) was an American mathematician who made important contributions to solving Hilbert's 16th problem .

Ragsdale grew up on a farm and studied at Salem Academy and Guilford College in Greensboro . After completing her bachelor's degree in 1892, she went on a scholarship to Bryn Mawr College , which was followed by a year at the University of Göttingen with Felix Klein and David Hilbert thanks to a scholarship she won . She then taught at the Bryn Mawr School in Baltimore before returning to Bryn Mawr College, where she received her PhD in 1906. The dissertation (with Charlotte Angas Scott ) built on work in Göttingen with Hilbert and was her only publication. From 1911 to 1928 she was a professor at Woman's College of North Carolina in Greensboro (now the University of North Carolina at Greensboro ). From 1926 to 1928 she headed the faculty.

Ragsdale turned in her dissertation (like several others of Hilbert's students at the same time) to real algebraic geometry and especially Hilbert's 16th problem, which asks about the number and arrangement of ovals and branches of real algebraic curves of given degree. In particular, she investigated real curves with even degrees and discovered that the difference pn between the number of even and odd ovals (i.e. with an even or odd number of other ovals within the respective oval) is a topological invariant (the Euler characteristic of the Ovals of limited area). In her work, she formulated some assumptions about an upper limit (depending on the degree of the curve) for the number of even and odd ovals in a curve of degree 2k, but these were refuted by Oleg Wiro in 1979 and by Ilia Itenberg in 1994. The problem of what exact upper limits exist instead is open.

Web links

  • Virginia Ragsdale - Agnes Scott College biography by Lawrence H. Riddle, December 8, 2010

Individual evidence

  1. ↑ Life data according to Jeremy Gray: The Hilbert Challenge , Oxford University Press, 2000, p. 145
  2. ^ V. Ragsdale: On the arrangement of the real branches of plane algebraic curves , American Journal of Mathematics 28, October 1906, pp. 377-404 (English)
  3. ↑ Ilia Itenberg, Oleg Viro : Patchworking algebraic curves disproves the Ragsdale conjecture , The Mathematical Intelligencer 18 No. 4, December 1996, pp. 19–28 (English; at CiteSeerX )
personal data
SURNAME Ragsdale, Virginia
BRIEF DESCRIPTION American mathematician
DATE OF BIRTH December 13, 1870
PLACE OF BIRTH Jamestown , North Carolina
DATE OF DEATH June 4, 1945