## The Math Genealogy tree

Since the genealogy database is not available in raw form, I spidered it in April 12 2008 and scraped the link data from the 1.5 gig large HTML directory, to get the topology of the tree. I got 104185 entries with mathematicians numbered from 1 to 120915. Entered into Mathematica, I have a list of pairs (n,m), which reads that m is a "advisor" of n. Now, I assign a label "generation" g to each mathematician, which means that the mathematician has a Grand^{g-1}dad, but not a Grand

^{g}dad. I also assign a label "weight" w, to each mathematician X, which is the number of mathematicians which have X as an ancestor.

Visualizing the graph is difficult. Putting the mathematicians on a square and connecting (advisor,student) links produces a mess but illustrates how the database was built. You can see it if you load the PS file. There is a correlation between generation and number, but it is not uniform. We next want to render a tree where mathematicians with larger weight are enlarged and the generation sorts the tree better.

## My Genealogy

Back to "random and silly" pages Euler is my Grand^{11}Dad (if the PhD Adviser is defined as "Dad"). Leibniz is my Grand

^{14}Dad. This is not very special. 50'000 mathematicians (almost half of the genealogy tree) share the same property. [W] are links to Wikipedia entries. [G] links to genealogy entries.

Erhard Weigel 1625-1699 [W] [G], Popularizer of science |
Gottfried Leibniz 1646-1716 [W] [G], Invention of Calculus |
Jacob Bernoulli 1654-1705 [W] [G], Seperable differential equations |
Johann Bernoulli 1667-1748 [W] [G], L'Hopital rule | ||||

Leonhard Euler 1707-1783 [W] [G], Euler formula |
Joseph Lagrange 1736-1813 [W] [G], Lagrange multipliers |
Jean-Baptiste Fourier1768-1830 [W] [G], Fourier series |
Johann Dirichlet 1805-1859 [W] [G], Dirichlet principle | ||||

Rudolf Lipschitz 1832-1903 [W] [G], Lipshitz condition |
Felix Klein 1849-1925 [W] [G], Erlanger program |
Ferdinand Lindemann 1852-1939 [W] [G], Pi Transcendence |
Arnold Sommerfeld 1868-1951 [W] [G], Fine-structure constant | ||||

Karl Herzfeld 1892-1978 [W] [G], Physical chemistry |
John Wheeler 1911-2008 [W] [G], Black hole |
Arthur Wightman 1922- [W] [G], Quantum field theory |
Oscar Lanford 1940- [W] [G], Feigenbaum fixed point | ||||