Prof. Laurie Rousseau-Nepton,
University of Toronto

Abstract

Stars continuously affect their surroundings through radiation, mechanical feedback, and by producing and returning new elements to the interstellar medium. These new elements can eventually be recycled to form new stars, affecting their characteristics and evolution. Also, stars form differently depending on environmental factors which can vary from galaxy to galaxy, location to location. As a result, each star forming region has its own story. During this presentation, I will introduce SIGNALS: the Star formation, Ionized Gas and Nebular Abundances Legacy Survey. By studying 50,000 regions where stars actively form, the SIGNALS' collaboration aim at understanding what triggers their formation, how efficiently stars form, what are their characteristics, and how each generations transform the surrounding gas and ultimately our Universe. The development of astronomical instruments, specifically spectro-imagers, is central to this work. I will also briefly present my plans to build a new prototype instrument to be developed and tested at UofT.

Timbits, coffee, tea will be served in STI A before the colloquium.

Louis Deslauriers,
Physics Department; Faculty of Arts and Sciences
Harvard University

Abstract

Despite overwhelming evidence that students learn more when actively engaged, traditional lecturing still dominates college STEM classrooms. Why do students and faculty continue to accept the traditional lecture as effective instruction? I’ll present findings suggesting that the ease of listening to a polished lecture can mislead both students and instructors into overestimating how much learning is happening. In contrast, the more demanding approach of deliberate practice—structured, effortful, and iterative—is often considered the gold standard of active learning, a kind of active learning on steroids. Rooted in expertise research, it has been shown to produce significantly greater learning gains.

I’ll discuss how cognitive psychology helps explain this disconnect, particularly through the concepts of perceived fluency, feeling of learning, and actual learning. These misperceptions carry real consequences for physics education—for example, student course evaluations often reward lectures that feel good over those that teach well.

I'll also share how we’re bringing AI into the classroom to enhance active learning. In one application, we use real-time AI to answer student questions during class, increasing engagement and interaction. In another, we’re developing a high-performance AI tutor that mimics expert human teachers, offering personalized support at scale. By combining research-based teaching with the latest AI tools, we aim to reshape how students learn physics in both large and small courses.

Timbits, coffee, tea will be served in STI A before the colloquium.

John Schreiner
Past President, Medical Physics for World Benefit
Former Chief Medical Physicist, CCSEO at KHSC
Emeritus Professor, Oncology and Physics, Engineering Physics & Astronomy,  Queen’s University

Abstract

Radiation Therapy is one of the four main options for cancer treatment with about 50% of cancer patients receiving radiotherapy at some point in their care. The ability to deliver highly targeted personalized treatment has advanced considerably in the past four decades because of improvements in the  imaging and dose calculation systems for treatment planning, in the control and sophistication of radiation delivery units, and in further improvements in treatment systems enabling dose delivery verification prior to patient irradiation. In this talk I will describe these advances through a personalized review of changes over a career. The talk will focus primarily on external beam photon treatment highlighting some of the physics that defines dose calculation and delivery. Some specific treatment techniques will be described to illustrate how the advances have impacted patient care.

Timbits, coffee, tea will be served in STI A before the colloquium.

Prof. Kai Wang
McGill University

Abstract

Photons, the particles of light, play a crucial role in nearly all quantum technology platforms, as they are ideal carriers of quantum information. However, the optical elements used in these quantum systems remain conventional, relying on bulky optics such as lenses, beam splitters, wave plates, and mirrors, which are either unsuitable or suffer from poor scalability. Recent advances in metamaterials, particularly metasurfaces, are driving a transformative shift in quantum photonics. Metasurfaces, composed of one or a few layers of tailored nano-resonators, offer unprecedented flexibility in controlling light across all degrees of freedom, combining miniaturization with scalability. This lecture will explore how these artificially engineered materials and nanostructures can be designed and manufactured to facilitate the generation, manipulation, and measurement of quantum states of light. Specifically, I will present examples from our research that demonstrate the use of nanostructured metasurfaces to perform quantum state tomography for photons, achieve nontrivial transformations of entangled photonic qubits, and conduct quantum state discrimination. These examples will highlight how the latest advances in nanotechnology are reshaping the fundamental building blocks of optical elements in quantum science and technology.

Timbits, coffee, tea will be served in STI B before the colloquium.