HOROWITZ SEMINAR
PROBABILITY, ERGODIC THEORY and DYNAMICAL SYSTEMS
Monday, 28/10/2002, at 14:30 in: room 210, Schreiber Bldg.
Dan Romik (Weizmann I.)
will speak on
Limit shapes of random partitions.
Abstract:
A partition of n is a representation n = a_1 + a_2 + ... a_k of n as a sum
of integers arranged in decreasing order. A partition may be drawn in a
natural way as the graph of a decreasing function on [0,oo), the so-called
Young diagram. A theorem of A. Vershik says that for a "typical" partition
of a large integer n (that is, for a fraction of partitions of n that
tends to 1 as n-->oo), the Young diagram will resemble a scaling of the
function f(x) = -log(1-exp(-cx))/c, where c=pi/sqrt(6), in other words
random partitions have asymptotically a limit shape given by the function
f(x). I will show how this result is derived and how it can be extended to
treat various sub-classes of partitions defined by imposing restrictions,
such as: partitions without repeated numbers, partitions without two
consecutive numbers etc. so each such sub-class there is a formula for the
limit shape that describes the behavior of a "typical" element in the
sub-class.
To suggest a talk (yours, or someone elses), contact
Jon. Aaronson:

Last update on 20/10/02.