# Professor David Aldous

University of California, Berkely

## Probability Models for Splitting and Coalescing.

``Branching processes" are one of the most classical topics in applied
probability. We commonly picture a process of discrete individuals,
but we could also interpret classical branching processes as
``combinatorial splitting processes" in which unit mass is split into
smaller andsmaller pieces. Here we say ``combinatorial" to contrast with
more realistic ``geometric" models which explicitly refer to d-dimensional
space. The talk will briefly describe some such processes,
as a warm-up to our topic of ``coalescing processes", in which
in which initially-small elements merge together. In the applied
probability literature, the only well-studied example is Kingman's
coalescent, a centerpiece of modern mathematical population genetics.
But combinatorial and geometric coalescent processes have been studied in
several other areas of science (statistical physics, polymers, astronomy). The purpose of our talkis to bring this topic to the attention of the mathematical probability community.

Refreshments will be served in Skiles 236 prior to the lecture.

## Brownsian Excursians, Critical Random Graphs and the Multiplicative Coalescent

### Academic Vita

**Born:** 13 July 1952
**Education: **

B.A. (Mathematics) 1973, Cambridge University

Ph. D. (Mathematics) 1977, Cambridge University.

**Employment: **

St. John's College, Cambridge. Research Fellow 1977-1979.

Department of Statistics, University of California, Berkeley.

Assistant Professor 1979-1982

Associate Professor 1982-1986

Professor 1986 - present.

**Awards, etc: **

Rollo Davidson Prize 1980

I.M.S. (= Institute of Mathematical Statistics) Fellow 1985

Loeve Prize in Probability 1993

Fellow of the Royal Society 1994

Research supported by N.S.F., 1979 - present.

**Invited talks: **

Invited Speaker, Ecole d'Ete St Flour 1983

Special Invited Speaker, Conference on Stochastic Processes, 1979, 1988.

I.M.S. Special Invited Lecturer 1982, 1988

I.M.S. Wald Lecturer 1993.

**Professional service: **

I.M.S. Council 1987-1989

Associate Editor, Annals of Probability 1982-1987, 1994 - present

Associate Editor, Annals of Applied Probability 1989-present

Associate Editor, J. Math. Analysis 1986-1991

Associate Editor, J. Theoretical Probability 1988 - 1995.