[Seminar] An Invitation to Topological String Theory (Dr. Kento Osuga, University of Sheffield, UK)

Title: An Invitation to Topological String Theory

Abstract: I will introduce the beauty of interplay among quantum field theory in various dimensions. More concretely, I will give an elementary review of fascinating relations among topological A-models and B-models, Chern-Simons theory, Seiberg-Witten theory, and matrix models. This talk will be designed for nonexperts so everyone in theoretical physics is welcome to join, including students. Research talks with more technical details may follow next week (and onwards) if there are interests. 

Visit: Dr. Kento Osuga (Postdoctoral Research Associate, University of Sheffield)

Visit: Dr. Kento Osuga (Postdoctoral Research Associate, University of Sheffield)

[Zoom Seminar] Tensor Field Theories: Renormalization and Random Geometry (Dr. Nicolas Delporte, Toriumi Unit)

Title: Tensor Field Theories: Renormalization and Random Geometry

Abstract: In the talk, I will share an overview of my research during my PhD thesis. After a practically-minded introduction to renormalization and conformal field theories (CFT), we will see the essential tools developed for tensor models and their large-$N$ expansion. In the second part, I will focus on results of $d>1$ tensor field theories: melonic CFTs, breaking of symmetries. In the last part, we will revive an old approach to study and renormalize an interacting scalar quantum field theory on Galton-Watson random trees, through random walks, which may prove useful for tensor models to escape the melonic large-$N$ limit.

Zoom:

https://oist.zoom.us/j/94081328725?pwd=aFBTdkUvZTdXVU1BYTd6bTUvZHJKdz09

Meeting ID: 940 8132 8725
Passcode: 609087

Colored Tensor Models Review by Yi-Shan

Presentation

Faculty Lunchtime Seminar: Quantum Gravity, Quantum Observables, Wilson Loops, and Geometric Flux (Prof. Reiko Toriumi, OIST)

Title: Quantum Gravity, Quantum Observables, Wilson Loops, and Geometric Flux

Abstract: I will brainstorm and introduce you to the type of problems that I tend to think about in quantum gravity. The title suggests some of the key concepts that I will visit in this talk in order to arrive at the recent interesting result that my collaborators and I discovered, namely, the notion of geometric flux in gravity.

Colored Tensor Models Review by Yi-Shan

Weekly presentaion

Journal club (Riccardo Martini): Boundary graphs in tensor models

We will introduce boundary graphs in tensor models and describe their meaning and construction.

Presidential Lecture - "The Square Peg Problem" by Dr. Andrew Lobb

The phrase "A square peg in a round hole" means something or someone conforming to unsuitable surroundings.  It's an unsolved conjecture over a century old that given any shape of hole - in other words any closed curve in the plane - you can always find four points on the curve that form the vertices of a square.  This says that square pegs can be made to fit into any shape hole, not just into square ones! I'll talk about this conjecture, its history, recent progress, and surprising and beautiful connections with famously one-sided surfaces such as the Moebius strip and the Klein bottle.

Andrew Lobb was an undergraduate at Oxford University and then took up a Kennedy Scholarship at Harvard University for his PhD studies.  During these studies, he became interested in low-dimensional topology and wrote his thesis on applications of quantum knot invariants to 4-dimensional problems. Dr. Lobb moved back to the UK for a postdoctoral position at Imperial College London, then returned to the USA for second postdoc at Stony Brook which included six months leave to take part in a program at MSRI.  He has been at Durham University in the UK since 2011.

Colloquium: "Simplicial homology, part IV" by Dr. Guilherme Sadovski

Speaker: Dr. Sadovski is a member of this unit (visit his page)

Minicurse: Morse Theory

This session will represent an introduction to several more advanced topological topics that are important in different branches of mathematics and physics.