In CS131, we see the “Proof from the Book” due to Euclide that the number of prime numbers is infinite. Here is another favorite proof that is based on elementary facts. Suppose that is a list of all the primes. From what we have learnt about the  sum of geometric progressions we know that for […]

Few days ago I uploaded on Arxiv our preprint “Novel Dense Subgraph Discovery Primitives: Risk Aversion and Exclusion Queries”.  This is joint work with Tianyi, Nao, and Jakub. In this paper we study the following extension of the densest subgraph problem (DSP) that is known to be solvable exactly in polynomial time on graphs with […]

For those in Boston, visit the MIT Museum. Amazing machines at exhibition all created by Arthur Ganson, including this (funny) one: Here you can hear Arthur Ganson talking about his machines at a TED event.