Scientists at the University of Toronto produce a wide variety of interesting research, a lot of which is generated from very specific, seldom-heard topics. Here are three researchers who’ve made their niche probing the underexplored.
Hummingbird metabolisms
Kenneth Welch Jr. is an associate professor in the Department of Biological Sciences at UTSC, and he has studied hummingbird metabolisms for over a decade.
Hummingbirds aren’t just pretty to look at — they’re also fascinating case studies of extreme metabolisms. They beat their wings at such a terrific speed that they need to eat every half an hour. According to Welch’s calculation, a flying hummingbird has no stores of energy to rely on; they hover almost exclusively on the nectar they have consumed within the past hour.
One way that Welch’s lab studies hummingbird metabolisms is to look at how much oxygen the birds consume, as they need oxygen to break down the sugars and release carbon dioxide. One way to track oxygen consumption is by measuring ‘VO2 max’ — the volume of oxygen per unit of body weight used in a certain amount of time.
In an interview with The New York Times, Welch said that a hummingbird’s VO2 max can go up to 60 millilitres per gram of body weight per hour — many times that of an average human.
In a more recent study, Welch’s lab looked at the impact of certain insecticides on hummingbirds. The lab found that neonicotinoid insecticides — some of the most common and toxic insecticides on the market — quickly reduce a hummingbird’s energy expenditure temporarily, which can be dangerous for animals that burn through their food so quickly.
The life and death of stars
Maria Drout studies the life of stars — how they are born, how they change over time, and ultimately how they die. She was an associate researcher at the Dunlap Institute for Astronomy and Astrophysics before becoming an assistant professor at the Department of Astronomy & Astrophysics. Drout achieved high-profile success in observing a highly-energetic stellar merger between two neutron stars, the superdense remnants of massive stars that have collapsed inward.
In 2015, researchers at the Laser Interferometer Gravitational-Wave Observatory began to detect gravitational waves — previously undetected ripples in the fabric of space time that Albert Einstein’s general theory of relativity predicted.
In 2017, Drout’s team was responsible for detecting visible light from one such gravitational wave event: a collision between two neutron stars so intense it produced a ‘kilonova’ explosion, one step up from a regular supernova.
In 2019, Drout was awarded the prestigious Polanyi Prize in Physics, a $20,000 prize that is named for University of Toronto Nobel Laureate John Charles Polanyi.
The kilonova event that Drout and her team observed was regarded as the start of ‘multi-messenger’ astronomy, by which astronomers can detect multiple types of signals coming from the same event to study it better. Their data also showed hints that massive neutron star mergers can produce heavier elements — a process which regularly occurs in the merger of non-neutron stars.
Since then, an American-European team confirmed in 2019 that the merger did create new elements after they reanalyzed the data and found the presence of the element strontium.
The rich field of number theory
Jacob Tsimerman is a U of T alum and associate professor in the Department of Mathematics. He is best known for his contributions to number theory, the study of the properties and relationships of whole numbers.
In 2015, Tsimerman was awarded the Shanmugha Arts, Science, Technology & Research Academy Ramanujan Award for his research. The prestigious $10,000 award is given to mathematicians working in fields related to the work of the genius mathematician Srinivasa Ramanujan. Award winners have to be below the age of 32 — the age Ramanujan died.
Number theory is a wide field of mathematics research that has rich applications to cryptography and computer science. Many results in the field are fiendishly complicated, but some of them are so straightforward that they were proved centuries ago.
A great example of this is ancient mathematician Euclid’s proof that there are an infinite number of prime numbers, which dates back to around 300 BCE. As prime numbers are only divisible by one and themselves, they are valuable for cryptographers looking to build secure encoding systems. The search for larger and larger primes for cryptography has spanned decades — the current record-holder has over 24 million digits.
Tsimerman’s prize was awarded for his partial solution to the Andre-Oort conjecture, an open-ended question about Shimura varieties — complex mathematical objects that can be described by points along a curve. His proof of the conjecture was only a partial success, however, as it is still being proved in other cases and with different assumptions. The oldest version of the conjecture was proposed in 1989, but the work is ongoing.
“Mathematicians are sometimes too quick to dismiss the possibility that we can solve something,” Tsimerman said to Quanta Magazine in 2020. “Math is really hard, and people sometimes overlook things.”
