Purdue Quantum Theory Neighborhood Seminar

Logistics

Email list: We maintain an email list through Purdue's Listserv. To request to be added, please email quantum-theory-request at lists.purdue.edu.
Schedule: for the fall 2026 semester, the regular meeting time is Mondays, 1-2pm Eastern. For the 26-27 academic year, we aim to have external speakers approximately every two weeks, with internal speakers on the other weeks.
Location: Hall of Data Science and AI (DSAI) 1069 for Monday events. Most seminars will be in-person but some will be virtual. Please consult the calendar below. When we have virtual talks, we will arrange watch parties in this room (although you are of course welcome to watch over Zoom as well). Wednesday and Friday events will have variable location that will be communicated via the email list.
Zoom link: For security reasons, the Zoom link is only available to individuals who are on the email list.
Affiliated faculty: Saugata Basu, Claudio Chamon, Shawn Cui, Colleen Delaney, Tyler Ellison, Ananth Grama, Birgit Kaufmann, Ralph Kaufmann, Laimei Nie, Yuxiang Peng, Eric Samperton, Wojciech Szpankowski, Jukka Vayrynen, Wei Zhan, Ruizhe Zhang

Scope

More-or-less anything related to the theory of quantum mechanics is fair game, but we tend to be especially interested in mathematically rigorous research related to quantum computation, quantum information and quantum error correction, and adjacent matters in condensed matter theory. The current and past schedules should give the most direct sense of the topics of interest.

View past semester schedules

Fall 2026 Schedule

Date & Format	Speaker	Title
Monday 24 August 1-2pm IN-PERSON		Organizational meeting
Monday 31 August 1-2pm IN-PERSON	Ruizhe Zhang, Ralph Razzouk	Quantum Theory Neighborhood Meeting We will have two twenty minute talks from Purdue researchers, with time for lots of questions.
Labor Day is 9/7		NO TALK
Monday 14 September 1-2pm IN-PERSON	Yabo Li, Gert Vercleyen	Quantum Theory Neighborhood Meeting We will have two twenty minute talks from Purdue researchers, with time for lots of questions. Li: 1d Quantum State Preparation via Measurement and Feedback. Vercleyen: 989 Fusion Categories Walk Into a Search Bar.
Monday 21 September 1-2pm IN-PERSON	Muhammad Salah Shatla, Shashank Boopathi+Bhavya Lakhina+Esha Sury+Dhruv Upreti (team talk)	Quantum Theory Neighborhood Meeting We will have two twenty minute talks from Purdue researchers, with time for lots of questions. Boopathi et al: Financial Portfolio Optimization Using Quantum Annealing. Shatla: Score-based Generative Modeling on The Quantum State Space.
Monday 28 September 1-2pm IN-PERSON	Victor Gurarie (UC Boulder)	Path integrals and QFTs of monitored quantum systems Recent years have seen growing interest in quantum systems subject to measurements that actively influence their evolution. Beyond conventional unitary dynamics, such monitored quantum systems can be steered through measurement backaction, leading to novel dynamical phases of matter and measurement-induced phase transitions. In this talk, I will discuss how the inclusion of measurements modifies the path integral formulation of quantum mechanics, providing a unified and systematic framework to describe continuous observations. I will illustrate this approach in several contexts: from a single particle under continuous monitoring to interacting one-dimensional systems of bosons and fermions. These examples demonstrate how measurement enrich possible behavior of quantum systems.
Monday 5 October 1-2pm	Rescheduled	NO TALK OR MEETING
Fall Break is 10/12 and 10/13		NO TALK
Monday 19 October 1-2pm IN-PERSON	Charles Stahl (Stanford)	Many-body Brownian ratchets and active memories Systems driven out of equilibrium can realize phenomena forbidden in equilibrium, such as robust information storage. Yet it is often unclear how to realize a given set of abstract dynamics in a physically natural driven system. In this talk, I show how to simulate any local active dynamics with a many-body Brownian ratchet: a bilayer system whose two layers are coupled to baths at different temperatures. Applying this construction to Toom's rule, I construct a nearest-neighbor Ising model whose ferromagnetic phase is stable to symmetry-breaking perturbations. Finally, I show that a related construction, sliding two Ising models against each other, yields an ordered state with a very long lifetime in one dimension.
Monday 26 October 1-2pm IN-PERSON	Lin Lin (Caltech)	Bath-assisted cooling without resets Recent advances in quantum Gibbs sampling have made dissipative dynamics a competitive algorithmic tool for thermal and ground-state preparation. We introduce a new cooling mechanism, in which a single coherent bath contact transfers the initial-state information into bath modes that subsequently decouple. The system and the remaining bath then follow an interacting ground-state path, and the bath is discarded only at the end. For a class of weakly interacting, gapped fermionic systems, we prove preparation from arbitrary mixed states in total physical time polylogarithmic in the system size and inverse global trace-norm error. Joint work with Xie-Hang Yu and Zherui Chen. arXiv:2609.4032
Monday 2 November 1-2pm IN-PERSON	Shiyu Zhou (Perimeter)	TBA TBA
Monday 9 November 1-2pm IN-PERSON	Wilbur Shirley (UChicago)	TBA TBA
Monday 16 November 1-2pm IN-PERSON	Internal speakers TBD	Quantum Theory Neighborhood Meeting We will have two twenty minute talks from Purdue researchers, with time for lots of questions.
Monday 23 November 10-11am VIRTUAL	Zishuo Zhao (Tsinghua)	Axiomatization of Levin-Wen wave function Levin-Wen model describes topological orders for a given unitary fusion category. An intrinsic characterization of the Levin-Wen ground-state wave functions without prior categorical symmetry nor Hamiltonian is a major open question. We answer this question in terms of six axioms on a family of wave functions associated with lattices in different scales. These conditions allow us to reconstruct the underlying unitary fusion category, and prove that the wave functions are the corresponding Levin-Wen ground states. By weakening some of the conditions, our approach provides a framework for studying lattice models before RG fixed points.
Monday 30 November 1-2pm IN-PERSON	Internal speakers TBD	Quantum Theory Neighborhood Meeting We will have two twenty minute talks from Purdue researchers, with time for lots of questions.
Monday 7 December 1-2pm IN-PERSON	TBD	TBD