Arnold's seminar September 12th, 2000 V.I.Arnold Plans of the seminar for autumn semester, 2000 Among other things, we are planning to discuss the following works and topics. 1. Ya.Dymarski. Membranes, ellipsoids and symmetric operators with multiple eigenvalues. 2. P.Biran. Symplectic packing in dim 4. Geom. Funct. Anal. 1997:7, 420--437. Constructing new ample divisors out of flows. 1997 (?) 3. R.Low. Casuality in terms of linking in light ray space. E.g. in: Classic and Quantum Gravity 7 (1990), p.177, 11 (1994), p. 453. These papers and pther e-prints related to this topic are available from Robert Low's home-page: http://www.mis.coventry.ac.uk/~mtx014/. 4. M.Haiman. Papers where the number (n+1)^{n-1} appears in different siuations, E.g. J.Alg.Geom 3 (1994), 17--76, J.Comb.Th. 82 (1998), 74--111. These papers and other e-prints related to this topic are available from Mark Haiman's home-page: http://math.ucsd.edu/~mhaiman/. 5. Old works of Swedish mathematicians and astronomers on continued fractions. Do they contain a proof of Kuzmin's probability theorem, for example? A.Wiman. Ueber eine Wahrscheinliche Aufgabe bei Kettenbruchentwicklungen. Abh. Foehr (?) Stockholm 57 (1900), S. 589--846. H.Gylden. Fractions continues. CR Acad Sci Paris 197 (1888), 1584--1587. 6. S.Newcomb. Note on the frequency of digits. Amer Math. Monthly 4 (1881), 39--40. [Note. There's an error here, because AMM begins in 1894. Can anybody find the correct reference?] 7. Recent developments related to Lagrange's theorem about continued fractions. For example, Tsuchiashi--Korkina's theorem. 8. Statistics of numbers that appear in the expansions into continued fractions. For example, take a random number (p,q) \in Z^2 with p^2+q^2<=R^2, write p/q = a_1+1/(a_2+...), for a fixed n compute the probability of a_i=n as i -> \infty take the limit as R -> \infty Conjecture. The limit is the same Gaussian number p_n which gives the corresponding probability for almost all irrational numbers. 9. V.Chernov. New results on Vassiliev invariants. 10. Complexity according to J.Milnor (ask A.V.Chernavsky). 11. Theses of Napolitano, Ricardo Uribe, Mauricio Garay.