A new book underscores the pioneering work being done at Western in the philosophy of astrophysics and in the training of experts shaping the emerging field.
The Philosophy of Astrophysics: Stars, Simulations, and the Struggle to Determine What is Out There is the first edited collection of its kind. Positioned as “the first standard resource on the philosophy of astrophysics,” the book features a paper by Western philosophy professor Chris Smeenk, associate director of the Rotman Institute of Philosophy, and physics and astronomy professor Sarah Gallagher, director of the Institute for Earth and Space Exploration (Western Space).
Graduates Melissa Jacquart, MA’12, PhD’17, Marie Gueguen, PhD’19, and Cameron Yetman, MA’21, also contributed to the volume, which was created for scholars in the field looking to deepen their knowledge, and for philosophers and scientists seeking a basic understanding of the main issues in the philosophy of astrophysics.
“The number of people connected to Western involved with this book is a testament to the real sense of community developing here between our astronomers and astrophysicists and to the work that’s possible through the Rotman Institute,” said Smeenk, who supervised both Jacquart and Gueguen’s doctoral research, and sat on the supervisory committee of Nora Mills Boyd, one of the editors of the book.
Smeenk points to Yetman’s contribution, a bibliography providing a complete overview of all papers and books (in English) on the philosophy of astrophysics, completed as a summer graduate research project under the supervision of Rotman Institute members and physics and astronomy professors Pauline Barmby and Francesca Vidotto.
“The idea of a philosophy student connecting with an astrophysicist as part of their master’s program could only happen because we have the community here where people know each other and see the value of this kind of work,” Smeenk said.
“I’ve been pushing for a while now that there’s really interesting philosophy to be done in astrophysics and cosmology, so it’s great to see a group of junior scholars taking this concept and running with it.”
Inspiring the next generation: Exploring the philosophy of astrophysics
Jacquart, now a philosophy professor and associate director of the Center for Public Engagement with Science at the University of Cincinnati, cites the unique environment offered by the Rotman Institute, and Smeenk’s research as the “two central reasons” drawing her to Western for her graduate studies.
“Chris is a central figure in the philosophy of astrophysics and his mentorship and scholarship are key factors that led me to develop into the academic I am today,” she said. “Not only is he a founding figure in the field, but his research also demonstrates excellence in interdisciplinary work, and what scientifically informed philosophy and philosophically informed science looks like.”
Gueguen, who was recently awarded a Marie Sklodowska-Curie Actions Individual Fellowship grant, credits Smeenk’s “contagious enthusiasm,” for leading her to specialize in the philosophy of cosmology and astrophysics. “He and the Rotman community of philosophers, astrophysicists and physicists have been instrumental in shaping my views about the kind of philosopher of science I want to be.”
Smeenk and Gallagher’s collaboration on their paper, What’s in a Survey? Simulation-Induced Selection Effects in Astronomy, arose from conversations shared over dinner. The married couple first met as undergraduates in a quantum mechanics class at Yale, with their long-term personal relationship key in fostering professional connections and growing Western’s community of astrophysicists and philosophers.
“I’ve always engaged with philosophers much more than a standard astronomer and it’s the same for Chris,” said Gallagher, who also served as a science advisor to the president of the Canadian Space Agency from 2018-2022. “We interact socially with our colleagues, and I think that deep familiarity – even in a non-scholarly way – helped me know what sort of topic to bring to Chris as something I thought philosophers might be interested in.”
In this particular case, how the simulations that are used by Gallagher and others in her field to understand the triggering of quasars – bright swirling masses of gas and dust, powered by growing supermassive black holes at the centres of distant galaxies, billions of light years away – have changed over the course of her career. In many ways they have become much more sophisticated, but are still limited by what is possible to simulate in a reasonable amount of time with today’s computing resources.
“It seemed like a very fertile opportunity to have this intellectual conversation, because it turns out that some of that shift in how simulations are used is really interesting to the philosophers who are asking, ‘What’s an experiment? What is data? What tools and information are we using to try to understand the world?’” Gallagher said.
“That’s how this collaboration came about. I don’t see how that would have happened without our close relationship and my repeated encounters with the field. It’s definitely made me much more thoughtful as a scientist, and more critical in terms of challenging my assumptions and thinking about what a philosophical choice is, as opposed to something that is maybe more obviously a scientific choice.”
Smeenk also sees – and experiences – the benefits.
“From the philosopher’s point of view, it’s incredibly valuable to have scientists recognize the value of what you do from the start,” he said. “Often when a philosopher approaches a group of scientists, they have to prove their worth first, and show they can keep up on the technical material and say, ‘Here’s what I add that’s valuable.’
“It’s refreshing we have a community here where you don’t always have to start off with that. You start with mutual respect and the recognition that there are interesting problems that have fallen between our fields that we have to work out together to make genuine progress.
“Overall, this is the kind of work the Rotman Institute really prioritizes, where philosophers get their hands dirty and learn a lot about the science,” Smeenk said. “It’s often collaborative and you have to have someone who has expertise in both areas and then find a way of working together on important questions neither of you can fully pursue on your own.”