Department of Physics, National University of Singapore
Condensed Matter Seminar Series
To receive email notifications of this seminar series, please send an email to zouliujun@gmail.com to request.
Condensed Matter Seminar Series
To receive email notifications of this seminar series, please send an email to zouliujun@gmail.com to request.
Upcoming Seminars
(Both online and in-person seminars will be broadcast via Zoom.)
(Click the upper right corner of this page to see the previous seminars and their recordings.)
Time: 9am, November 13 2026, GMT+8
Location: Online
Zoom: https://nus-sg.zoom.us/j/88911975409?pwd=ixb7zXPuROkgclFcXZ2Wzh5vx6fmz4.1
Password: 835700
Speaker: Linhao Li
Title: Noninvertible symmetry on the lattice and topological phases
Abstract: Recently, the notion of symmetry has been generalized in many directions. One particularly interesting example is noninvertible symmetry, which does not possess an inverse operation. These novel symmetries have significantly broadened our understanding of quantum phases and phase transitions. In this talk, I will present a general class of noninvertible symmetries on the lattice, known as the Bilinear Phase Map (BPM), which provides a generalization of the celebrated Kramers–Wannier duality. This framework allows us to conveniently capture essential properties of noninvertible symmetries, such as fusion rules and noninvertibility. Furthermore, I will discuss a approach to classifying symmetry-protected topological (SPT) phases enriched by noninvertible symmetries, along with explicit lattice constructions realizing these phases.
The seminar series in the fall semester of 2026 is over, and the next seminar will take place in the spring semester of 2027.
Time: 9am, January 14 2027, GMT+8
Location: Online
Zoom: https://nus-sg.zoom.us/j/88040524767?pwd=C3287B7IySGWk2mQjia8I4QR4KdkPu.1
Password: 818970
Speaker: Michael Scheer
Title:
Abstract:
Time: 9am, January 28 2027 (rescheduled from November 6 2026), GMT+8
Location: Online
Zoom: https://nus-sg.zoom.us/j/88040524767?pwd=C3287B7IySGWk2mQjia8I4QR4KdkPu.1
Password: 818970
Speaker: Gautam Greddy
Title: Emergence of cognitive circuits in artificial systems
Abstract: Artificial neural networks now display hallmarks of cognition, while allowing us to perfectly measure and manipulate their internal activity. This makes them a new kind of "experimental system" for studying how cognition emerges in a collection of interacting units. What internal representations do these networks form when reasoning about the world? What mechanisms enable a fixed circuit to infer and adapt its computations to the current context? What determines when a network will memorize or generalize? This talk will explore these questions using paradigms inspired by neuroscience, in large language models and minimal models trained on synthetic data. A major focus will be on how language models leverage symbolic representations to generalize, how networks construct and leverage task representations, and how depth in modern architectures approximates a recurrent control system that implements adaptive inference of latent context variables.
Time: 9am, February 11 2027, GMT+8
Location: Online
Zoom: https://nus-sg.zoom.us/j/88040524767?pwd=C3287B7IySGWk2mQjia8I4QR4KdkPu.1
Password: 818970
Speaker: Luisa Eck
Title:
Abstract: