brian north he first fell in love with physics as a teenager growing up in Wisconsin. His high school physics program was not exceptional, and at times he struggled to keep up with class material, but those difficulties did nothing to dampen his interest in the subject. In addition to the core curriculum, students were encouraged to independently study topics they found interesting, and Nord quickly developed a fascination with the cosmos. “A touchstone that I return to often is space,” he says. “The mystery of traveling in it and seeing what is on the edge.”
Nord was an avid comic book reader, and the astrophysicist appealed to his desire to become part of something bigger. “There always seemed to be something special about having this kinship with the universe around you,” he recalls. “I always thought it would be great if he could have that deep connection to physics.”
Nord began cultivating that connection as a student at Johns Hopkins University. After graduating with a bachelor’s degree in physics, he went on to study at the University of Michigan, where he earned a master’s degree and a doctorate in the same field. At this point, he was already thinking big, but he wanted to think even bigger. This desire for a more complete understanding of the universe led him away from astrophysics and into the broader field of cosmology. “Cosmology deals with all the equipment and the caboodle, the whole setup,” he explains. “Our biggest questions are about the origin and fate of the universe.”
dark mysteries
Nord was particularly interested in parts of the universe that cannot be observed through traditional means. Evidence suggests that dark matter makes up most of the universe’s mass and provides most of its gravity, but its nature remains largely in the realm of hypothesis and speculation. It does not absorb, reflect, or emit any kind of electromagnetic radiation, making it nearly impossible for scientists to detect. But while dark matter provides gravity to pull the universe together, an equally mysterious force, dark energy, is pulling it apart. “We know even less about dark energy than we do about dark matter,” Nord explains.
For the last 15 years, Nord has been trying to close that gap in our knowledge. Some of his work focuses on the statistical modeling of galaxy clusters and their ability to distort and stretch light as it travels through the cosmos. This effect, known as strong gravitational lensing, is a useful tool for detecting the influence of dark matter on gravity and for measuring how dark energy affects the expansion rate of the universe.
After earning his Ph.D., Nord remained at the University of Michigan to continue his research as part of a postdoctoral fellowship. He currently holds a position at the Fermi National Accelerator Laboratory and is a senior member of the Kavli Institute for Cosmological Physics at the University of Chicago. He continues to investigate questions about the origin and fate of the universe, but his most recent work has also focused on improving the way we make scientific discoveries.
AI booster
When it comes to tackling big questions about the nature of the cosmos, Nord has always run into a big problem: while his mastery of physics can sometimes make him feel like a superhero, he’s only human, and humans aren’t perfect. They make mistakes, are slow to adapt to new information, and take a long time to get things done.
The solution, Nord argues, is to go beyond the human, into the realm of algorithms and models. As part of Fermilab Artificial Intelligence Project, spends his days teaching machines how to analyze cosmological data, a task for which they are better suited than most human scientists. “Artificial intelligence can give us models that are more flexible than what we can create ourselves with pencil and paper,” Nord explains. “In many cases, it does better than humans.”
Nord continues this research at MIT as part of the Martin Luther King Jr. (MLK) Visiting Professors and Scholars Program. Earlier this year, she joined the Nuclear Science Laboratory (LNS)with Jesse Thaler in it Physics department and the Center for Theoretical Physics (CTP) as host of its faculty. Thaler is the director of the Institute for Artificial Intelligence and Fundamental Interactions (IAIFI) at the National Science Foundation. Since he came to campus, Nord has focused his efforts on exploring the potential of AI to design new scientific experiments and instruments. These processes normally take an enormous amount of time, he explains, but AI could speed them up quickly. “Could we design the next particle collider or the next telescope in less than five years, instead of 30?” He asks.
But if Nord has learned anything from the comics of his youth, it’s that with great power comes great responsibility. AI is an incredible scientific asset, but it can also be used for more nefarious purposes. The same computer algorithms that could build the next particle collider are also the basis for things like facial recognition software and risk assessment tools that inform sentencing decisions in criminal courts. Many of these algorithms are deeply biased against people of color. “It’s a double-edged sword,” Nord explains. “Because if (AI) works better for science, it works better for facial recognition. So, I’m working against myself.”
Culture Change Superpowers
In recent years, Nord has sought to develop methods to make the application of AI more ethical, and his work has focused on the broad intersections between ethics, justice, and scientific discovery. His efforts to combat racism in STEM have established him as a leader in the movement to address inequalities and oppression in academic and research settings. In June 2020, he collaborated with members of Particles for Justice, a group that includes MIT professors. daniel harlow and Tracy Slatieras well as a former MLK Visiting Fellow and CTP Researcher Chanda Prescod-Weinstein — to create the Academic Strike for Black Lives. The strike, which arose in response to the police killings of George Floyd, Breonna Taylor and many others, called on the academic community to oppose anti-black racism.
Nord is also co-author of black lighta curriculum for learning about black experiences, and co-founder of change now, which put together a list of calls to action to create a fairer lab environment at Fermilab. As co-founder of deep skies, also strives to foster justice-oriented research communities free from traditional hierarchies and oppressive power structures. “The basic idea is just humanity over productivity,” he explains.
This work has led Nord to reconsider what motivated him to pursue a career in physics in the first place. When he first discovered his passion for the subject as a teenager, he knew he wanted to use physics to help people, but he wasn’t sure how. “I was thinking about creating some life-saving technology, and I’m still hoping to do it,” he says. “But I think maybe more of my direct impact, at least at this stage of my career, is trying to change the culture.”
Physics may not have guaranteed Nord’s flight or X-ray vision, at least not yet. But in the course of his long career, he has discovered a more substantial power. “If I can understand the universe,” he says, “maybe that will help me understand myself and my place in the world and our place as humanity.”
