Exploring the Universe with Curiosity and Light

Intro

I'm Jennifer Chan, a postdoctoral fellow at the Canadian Institute of Theoretical Astrophysics (CITA) and the Dunlap Institute of Astronomy & Astrophysics at the University of Toronto, supported by the joint CITA and University of Toronto Faculty of Arts & Science Fellowships. I received my Ph.D. and MS.c. in Astrophysics at the University College London, and Bachelor in Physics at the University of Oxford. I investigate cosmic magnetism — examining how magnetic fields arise, span galaxies, and influence the Universe — and delve into the "teenage years" of the cosmos. During this critical era, the first stars, first galaxies, and first quasars (bright objects powered by black holes) transformed the early, simple, neutral Universe (captured by the Cosmic Microwave Background (CMB) radiation) into the intricate, structured cosmos we see today, brimming with magnetized plasma. Yet, much remains unknwon about how these dramatic changes unfolded. I use the journey of light as our guide to uncover these cosmic mysteries, along with modern radio telescope datasets!

Beyond my research work, I take delight in forming and cultivating meaningful connections, painting space-inspired art, savoring delicious food, and exploring the beauty of nature.

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Teaching & Mentoring

Teaching, for me, is a two-way journey. I believe that education is not just about imparting knowledge but about learning and growing alongside my students. Every interaction — whether in a classroom, during office hours, or through mentorship — broadens my perspective and deepens my understanding of both the subject matter and the diverse ways students engage with it.

I have taught physics and mathematics at the GCE A-Level and IBDP levels, guest lectured at undergraduate and graduate levels, graded Master’s courses, and supervised and co-supervised undergraduate research projects. Along the way, I have mentored students with aspirations spanning academia, research, and industry. Watching them grow and carve their own paths has been one of the most rewarding aspects of my career.

I am passionate about making physics and astronomy accessible and relatable. Through STEM outreach, I aim to spark curiosity and equip learners with multiple perspectives through the lens and tools of science. I am also deeply committed to engaging undergraduates with research and hands-on, real-time problem-solving, fostering their curiosity and critical thinking through experiential learning.

In my teaching, I emphasize timely feedback to foster reflective thinking and adaptability. I prioritize aligning goals and actions while maintaining transparency about expectations to create a supportive and engaging learning environment. I also adopt an inquiry-based approach, encouraging students to ask questions, refine their questions, explore ideas, and engage actively in the learning process.

I see teaching and mentoring as opportunities for mutual growth. My goal is to empower students to think critically, adapt to challenges, and follow their passions with confidence. In turn, their questions, ideas, and perspectives continuously inspire me to evolve as an educator.

If you are passionate about STEM and education, please feel free to reach out. Together, we can build an engaging, supportive network that nurtures insightful discussions, sparks fresh ideas, and cherishes our shared curiosity.

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Research

From Light to Insight: Uncovering How the Universe Evolved to the Current State

How Do We Uncover the Universe Evolution Story Using Cosmic Signals?

Magnetic Fields in the Changing Universe: Imagine putting on a pair of special sunglasses that reveal hidden patterns in everyday scenes. I use a type of light called polarized continuum radiation to do something similar with galaxies, clusters of galaxies, and the vast cosmic web. This light exposes the invisible magnetic fields — like hidden “threads” — that help regulate where stars are born, influence how galaxies grow and change, and guide high-energy particles, among many other important roles.

Hydrogen Gas in the Changing Universe: I also study the 21-cm line radiation, a distinctive signal produced by neutral hydrogen — the most abundant element in the Universe. As the Universe expands, this light is stretched out (or “redshifted”), letting us look back in time. It tells the story of the Epoch of Reionization — a critical period when the Universe transformed from being filled with neutral gas to becoming ionized. Think of the Universe’s evolution as a journey from infancy to maturity — from its embryonic phase captured in Cosmic Microwave Background (CMB) , to a mature cosmos filled with stars, galaxies, and black holes.

Bridging Theory and Observation

To turn our ideas of how the Universe evolved into real, testable predictions, I use cosmological radiative transfer that I derived from conservations laws of physics. This framework accounts for how light interacts with matter as the Universe expands. In simple terms, it allows us to take our models of the evolving universe to precise observables and see if they match what we observe through telescopes.

Innovative Analysis Tools for 360° Datasets

I’ve also developed a tool called curvelets on a sphere. Think of it as a smart analysis tool that scans a full 360° view, efficiently identifying and characterizing curved or elongated features. Originally designed to study all-sky astronomical images, it can also work with any spherical dataset — from 360° panoramic photos to medical imaging data like brain scans, as well as examples from the Science On a Sphere Dataset Catalog. It helps reveal hidden patterns and allows us to perform detailed, quantitative studies of curvilinear structures across different scales and directions. Check out this blog post and our open-source code.

Why Does This Matter?

By combining these techniques, my research builds tools that bridge theory and observation, paving a concrete pathway to unravel the story of our evolving Universe. We study how gas and magnetic fields work together to shape galaxies and the grand structure of the cosmos — and how they, in turn, are shaped by the processes of structure formation and evolution, which lie at the very heart of modern astrophysics and cosmology.

In addition, we examine how the journey of different types of light, traveling vast distances to reach us, offers new insights into these cosmic phenomena!

Whether you're a curious learner, a physics/astronomy/astrophysics student, or an educator looking for inspiring examples of how science unlocks the secrets of our Universe, if you’d like to hear more or get an engaging glimpse into the dynamic processes that have sculpted the cosmos over billions of years, please feel free to check out the UofT Universe Speaker Bureau, and other educational resources and outreach initiatives.

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Resources

Canadian-based Events and Opportunities

Explore a range of astronomy research opportunities, educational programs, and events available at the Canadian Institue for Theoretical Astrophysics, the University of Toronto, in Toronto, or across Canada:

• Undergraduate Astronomy Research Opportunities at the University of Toronto (UofT) and the Canadian Institute for Theoretical Astrophysics (CITA):
  • SURP: Summer Undergraduate Research Program
  • SURF: Summer Undergraduate Research Fellowships
• Summer School:
  • Dunlap Summer School: A hands-on program in instrumentation and observational techniques for upper-year undergraduates and early graduate students in astronomy, physics, or engineering.
• Other Summer Educational Programs:
  • Perimeter Scholars International (PSI) Start Program: An introductory program in theoretical physics for upper-year undergraduates, preparing them for advanced studies through intensive coursework and research exposure.
• AstroTours at the University of Toronto (UofT):
  • Webpage
  • Instagram
  • Free public events organized by students in the Department of Astronomy & Astrophysics at UofT. Enjoy feature talks, planetarium sessions, interactive demos (including meteorites!), and telescope observing opportunities.
• Astro on Tap T.O. (The Great Hall, Toronto):
  • Webpage
  • Facebook Event
  • Free public events at the Great Hall in Toronto featuring fun games, astronomy news, TED-style talks, and prizes! Roaming astronomers from the Dunlap Institute, UofT, and CITA engage with participants and answer questions.
Annual Events (at UofT, across the city of Toronto, or at other universities) :
• Science Rendezvous UofT: An annual public science festival at the University of Toronto featuring hands-on activities, demonstrations, and talks to inspire curiosity and engagement in science.
• Doors Open Toronto: An annual event offering public access to architecturally, historically, and culturally significant buildings across Toronto, including science and educational facilities.
• Science Rendezvous: Canada’s largest science festival, featuring interactive exhibits, demonstrations, and talks to inspire public engagement with science, technology, engineering, and mathematics.
• NSERC Student Resources: Funding opportunities, scholarships, and research programs for undergraduate and graduate students in natural sciences and engineering in Canada.
• Mitacs: Offers research internships, fellowships, and funding opportunities for undergraduate and graduate students in Canada, focusing on industry-academic collaboration.

This resource list was compiled with the assistance of ChatGPT by OpenAI.

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Contact

• Twitter
• Facebook
• Instagram
• GitHub

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