Strategyproof-Exposing Mechanisms Descriptions

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

Colloquium Speaker: Yannai Gonczarowski (Harvard) Title: Strategyproof-Exposing Mechanisms Descriptions Abstract: One of the crowning achievements of the field of Mechanism Design has been the design and usage of the so-called "Deferred Acceptance" matching algorithm. Designed in 1962 and awarded the Nobel Prize in 2012, this algorithm has been used around the world in settings ranging […]

Moduli spaces of graphs

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

Colloquium Speaker: Melody Chan, Brown Title: Moduli spaces of graphs Abstract: A metric graph is a graph—a finite network of vertices and edges—together with a prescription of a positive real length on each edge. I'll use the term "moduli space of graphs" to refer to certain combinatorial spaces—think simplicial complexes—that furnish parameter spaces for metric […]

The Tree Property and uncountable cardinals

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

Colloquium Speaker: Dima Sinapova (Rutgers University) Title: The Tree Property and uncountable cardinals Abstract: In the late 19th century Cantor discovered that there are different levels of infinity. More precisely he showed that there is no bijection between the natural numbers and the real numbers, meaning that the reals are uncountable. He then went on […]

Quantum statistical mechanics of charged black holes and strange metals

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

https://youtu.be/-Kjl8WehIPw Colloquium Please note this colloquium will be held at a special time:  4:00-5:00 pm. Speaker: Subir Sachdev (Harvard) Title: Quantum statistical mechanics of charged black holes and strange metals Abstract: The Sachdev-Ye-Kitaev model was introduced as a toy model of interacting fermions without any particle-like excitations. I will describe how this toy model yields […]

Complete disorder is impossible: Some topics in Ramsey theory

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

Colloquium Speaker: James Cummings,Carnegie Mellon University Title: Complete disorder is impossible: Some topics in Ramsey theory Abstract: The classical infinite Ramsey theorem states that if we colour pairs of natural numbers using two colours, there is an infinite set all of whose pairs get the same colour. This is the beginning of a rich theory, […]

The Mobility Edge of Lévy Matrices

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

Colloquium Speaker: Patrick Lopatto (Brown) Title: The Mobility Edge of Lévy Matrices Abstract: Lévy matrices are symmetric random matrices whose entry distributions lie in the domain of attraction of an alpha-stable law; such distributions have infinite variance when alpha is less than 2. Due to the ubiquity of heavy-tailed randomness, these models have been broadly […]

Clique listing algorithms

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

Speaker: Virginia Vassilevska Williams (MIT) Title: Clique listing algorithms Abstract: A k-clique in a graph G is a subgraph of G on k vertices in which every pair of vertices is linked by an edge. Cliques are a natural notion of social network cohesiveness with a long history. A fundamental question, with many applications, is […]

Doping and inverting Mott insulators on semiconductor moire superlattices

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

https://youtu.be/-NisBM-2a2I Speaker: Liang Fu (MIT) Title: Doping and inverting Mott insulators on semiconductor moire superlattices Abstract: Semiconductor bilayer heterostructures provide a remarkable platform for simulating Hubbard models on an emergent lattice defined by moire potential minima. As a hallmark of Hubbard model physics, the Mott insulator state with local magnetic moments has been observed at […]