Macquarie Colloquium Lecture (CANCELLED): Pomerance -- Sums and products

There is just a message from the organizer (earlier today, 
March 21) that this event has been cancelled. 

I am very sorry for any inconvenience this must have caused. 

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Macquarie University

Mathematics Department Colloquium Lecture

Room: W5C 232 

Date: Wednesday, 21/03/2012

Time: 1 pm

Speaker: Carl Pomerance, Dartmouth College

http://www.math.dartmouth.edu/~carlp/

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Title: Sums and products

Abstract: what could be simpler than to study sums and 
products of integers? Well maybe it is not so simple 
since there is a major unsolved problem: for arbitrarily 
large numbers $N$, can there be sets of $N$ positive 
integers where both the number of pairwise sums and 
pairwise products is less than $N^{2-\e[silon}$? Erdos 
and Szemeredi conjecture no. This talk is directed at 
another problem concerning sums and products, namely 
how dense can a set of positive integers be if it 
contains none of its pairwise sums and products? For 
example, take the numbers that are 2 or 3 mod 5, a set 
with density 2/5. Can you do better? This talk reports 
on joint work with P. Kurlberg and J. C. Lagarias.

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We will take the speaker out to lunch at the Staff Club. 
The lunch party departs from level 4 of E7A at 12 noon. 
Please join us.