[the capital of Denmark]. My parents both worked in Copenhagen, and most of my immediate family lived there. In my view, Life in Roskilde was like in any suburb in the U.S.
What did your parents do in Copenhagen?
My mom had her own company; it was a book-binding company. They made ads and graphical materials, like calendars. I remember they made ice cream signs. I liked studying these, so I would know all the new ice cream flavors before the season started. My mom was the boss of her company — which was unusual, because there weren’t a lot of women in her profession. We talk today about there being few women in math… but during my mom’s time there were no other women involved in the leadership at her company. Her customers would come up to her and ask for the boss and she’d say, “I’m all you get.” My dad was a civil engineer. He worked for a national lab.
[My mom] was the boss of that company — which was unusual, because there weren’t a lot of women in her profession.
Who were you closer to? Your mom or your dad?
I think I was closer to my mom. But since both my parents worked I became pretty independent. All I was interested in was horses and gymnastics. I didn’t own a horse, but I was riding on a farm three days a week. For gymnastics I did trampoline and tumbling, but not competitively. When I was a little older, I was coaching recreational gymnastics, which in retrospect opened my eyes for teaching
Did you know any other mathematicians?
I didn’t know anybody who worked as a mathematician. I knew about engineering, but I didn’t want to be an engineer because my dad was an engineer [laughs]. At that time there wasn’t a real focus in middle school or on what you’re going to do later. Most of the focus was on learning basic material… this was in the 1970’s and people were more concerned that kids should have time to play. During high school I wanted to study exercise physiology, which is related to what I work on today.
The main reason I wanted to study physiology was that one of the girls I was coaching with was studying exercise physiology, and I thought that was cool. The only problem was that I went to a college that didn’t offer that program. It only offered environmental biology. I focused on mathematics because the math professors seemed nice and offered lots of support. I went to a very small college that had maybe 500 to 1000 students called Roskilde University. It was a new university and was based on project-based learning. You had to write a report every semester. I think because of the project-based approach at least half of the people I studied with went on to do PhDs. A lot of us are sitting in faculty positions today..
I don’t remember a lot from elementary school, I remember my classmates and the teachers. But I don’t remember how we were being taught.. I don’t think there was nearly as much focus on academics. Math was the only subject that was taught at more than one level.… A big difference from here was that we had a significant focus on languages. We first had English, then German, and then in high school you could choose between French, Spanish or Russian. Languages were important. If you travel more than 100 miles, you’re no longer in Denmark and the people speak a different language. Not all shows on TV were in Danish, most science college books were in English, so you got used to it. Today, all Danish kids learn English as a foreign language from first grade.
Most of the focus was on basic material learning, what you need to do… this was in the 1970’s and people were more concerned that kids should have time to play and do fun things.
Do you think that learning the different languages set you apart when you came here?
Mathematics has always attracted people from a wide range of Nationalities. So while nobody else spoke Danish, I didn’t feel different coming from another country. When in Europe or Denmark, it is “normal” to speak more than one language, so I didn’t feel different; It was just part of what you were doing. My dad’s parents spoke German at home so I had heard it a lot. I had family in the U.S. and Germany, so I grew up hearing foreign languages and traveled every summer.
What language did you learn math in?
That was in Danish. But I didn’t take what would now be considered AP math in high school; I just took the standard level math because I wanted to study biology. I think my philosophy was to take opportunities when they appeared, not seeking them out. When I was in college, a group of professors used modeling to develop an anesthesia simulator. I was asked if I wanted to do a PhD working on this project. It was an industrial PhD, so you were in a company half of the time and at the university half of the time. That was fun, as the work was very application-driven and associated with biology. Moreover, it adhered to what I liked to do. I was always better at science and math than I was at the language arts and social studies. It was definitely easier for me.
I was always better at science and math than I was at the language arts and social studies.
What is a mathematician?
That’s a good question and I’m probably not the right person to ask. There are many kinds of mathematicians. Mathematics is as big as biology. I’m an applied biomathematician, so I use math to study biological problems. We are trying to understand what happens when you get up from your chair and you feel lightheaded… What is the control system in your body that breaks down? For example, if you’ve had knee surgery and you get an inflammation, your surgeon will tell you to get up and walk the day after the surgery because it promotes healing. However, they also warn you because you could faint. There are several hypotheses explaining why this happens, and it is not known which one is correct. I build mathematical models that can test one hypothesis versus the other. We do a lot of computation, a lot of simulations and modeling with equations. I don’t do a lot of what you would call “pure math,” proving theorems — our focus is to use math to solve problems.
Another example involves the heart; in the old days they didn’t know that arteries and veins are connected in a closed system. The theory was that the body created and disposed all the blood pumped out from the heart. In the early 1600s William Harvey discovered that blood was circulating. At that time, they knew how much blood was in the body because the gladiators would fall in the arena or people would die on the battlefield (The ancient physiologists were studying the gladiators.). They also knew how much you drink every day and how much blood was pumped out with each heartbeat. William Harvey made a very simple equation, any middle school student could do this: he took the amount of blood coming out per heartbeat, the number of heartbeats in a day and from that he deducted that “the body has to produce about 7,500 liters of blood in a day.”
William Harvey used his model, which was just a multiplication, to hypothesize that we must have a circulatory system and that tiny pores (capillaries) must like arteries and veins.. But his hypothesis was hard to prove because physiologists of those times didn’t have a microscope powerful enough look at the capillaries linking the arteries and veins.. Harvey’s theory wasn’t proven until 50 years later when two simultaneous discoveries used new light microscopes to study capillaries.
I like to use this example when I’m teaching because it’s a simple and you can make it more complex by using more advanced math, but you’re starting with the multiplication to learn how physiological quantities are related and can help in understanding and explaining how the system may work. I think the examples you see in middle school often aren’t that exciting and most of them are associated with physics, which may not be as fun for everybody. I still remember the first time one of my colleagues started his talk with the Harvey example… I’ve been working on how the blood flows through the body and what different questions you can answer by studying the cardiovascular system. It does not all have to be complicated just because it’s math.
It does not all have to be complicated just because it’s math.
Does the heart still have mysteries that are worth solving?
I don’t know if the heart does, but I’m really interested is the whole control system and that has a lot of mysteries. There are a lot of things we don’t know.
I was talking to a physiologist in Denmark and he asked: “Humans often faint when they get up suddenly, but what about giraffes?” When a giraffe lifts its head up after drinking, it’s about six meters up in the air. If a giraffe fainted every time it lifts its head after drinking, then the lion would get it. It doesn’t faint, why? What is different between the giraffe’s and the human’s control system? All mammals have the same sized heart relative to their body size, same blood pressure; a mouse, a rabbit, a giraffe and an elephant. All mammals, except for humans, have the approximately the same number of heartbeats in their lifetime. That’s not different for a giraffe. But something must be different, and maybe we can learn something from studying the giraffe control system to help us treat and diagnose diseases. In my work we use mathematical models to study these questions. It is sometimes easier, since you can manipulate models in a way you cannot do in the clinic to a human, or in the laboratory to animals
Engineers have used math for ages to design devices, but biologists traditionally don’t use math to study behavior or function. Typically, mathematicians find biology classes difficult because you have to memorize lots of material, and biologists find math hard because of the complex analysis of equations. In the last 25 years mathematical biology has become very popular because there are so many unanswered questions. And every time you answer one question you open ten new questions.
It sounds like you come from two fields that don’t necessarily talk to each other; what got you into biomath?
I think I always liked biology when I was young, but I was good at math. In high school I realized I wasn’t really that good at memorizing, making biology more difficult, but I liked the logic behind how systems work. I did a lot of coaching in gymnastics, and I was always interested in how the body works. These interests combined with going to a small college were the professors were good at showing us that math could be fun and used to solve real problems made me pursue a career in math biology.
Very few students think of math as a career in middle school. I think it’s because you don’t really see how it can be used. And all you know about is being an engineer… and I was the same way. Today there is much more of a focus on career options.
Very few students think of math as a career in middle school. I think it’s because you don’t really see how it can be used.
Is it the science that you started working on that took you out of Denmark? Did you ever imagine that you would be working in Raleigh, North Carolina?
I don’t think I knew where Raleigh was located, but because Denmark is such a small country and PhD programs are so small, most people do their PhD at the same university as their Bachelor’s and Master’s degrees. There are only five universities in Denmark, and they specialize in five different areas so you rarely move between universities. For part of your PhD program, however, you are expected to study abroad for six months. I went to NYU to study with professor Charles Peskin, who is famous for modeling blood flow in the heart. I also won a travel award to study a year abroad. I used this to go back to New York and then to Australia. These trips made me excited continuing my work outside Denmark. After completing my PhD I got offered a postdoc in Boston spending.
Later, when I applied for faculty positions I looked for positions both in engineering and in Math both in the US and in Denmark, but given that I was trained in math it felt more natural to work there. I decided to come to Raleigh, since the math department at NCSU has a long tradition for supporting faculty working in the interface between mathematics and biology.
Can we talk about the notion that in Denmark it’s not acceptable to say you’re good at something? What does that mean?
Denmark is a country where they like to pride themselves that everybody has equal opportunities and everyone is equal. It’s as good to be a plumber as it is to be a doctor. The doctors don’t make as much money and the plumbers make more than they would here. The cashier in the supermarket makes more than here; there are high minimum wages and high social standards. I think that really permeates through the society; it doesn’t mean that there aren’t kids that are better in school than others, but you didn’t really emphasize that when I went to school, though I think they do more now than when I grew up in the 1970s.
[Denmark is] a country where they like to pride themselves that everybody has equal opportunities and everyone is equal.
Were there grades?
You had grades starting in seventh grade.
So if you got a grade you wouldn’t show anyone?
Kids knew who was strong and who was less so, but you didn’t talk about it. After ninth grade Danish kids have different kinds of schools you can choose between. You can go to high school, which is the academic-type, like International Baccalaureate. Then there is a business-type high school, and then for the kids who wanted to be administrators or teachers, there is a teacher’s college. They also have vocational schools for professional trades such as plumbing or electrical work, which consists of a year of school and then an apprenticeship. To get into university, it’s like here — if they have 100 spots they take the 100 applicants with the highest grades… but math never filled up, so if you passed high school, you could get into math.
Do you have a discovery that you are particularly proud of or perhaps your middle school self would find really interesting?
I think the work I did for my PhD is what I’m most proud of — I developed a new way to predict blood flow and pressure in arterial networks using two coupled models. One for the large arteries, predicting blood flow and pressure in a network accounting for the explicit branching structure and size of the individual blood vessels including their radius, their length, etc… This model was coupled to one for the small arteries. I developed a way to predict blood flow and pressure in the small arteries using a fractal network, and a method to couple the fractal-type network with the network of large arteries.
What about a discovery that is on the horizon?
Right now I’m really excited about developing models for studying different hypotheses explaining the interaction between inflammation and the cardiovascular control system. I think that could give rise to some interesting insights because you are coupling several types of models together. This project is a team project involving a physiologist working with clinical studies, a cell biologist who’s interested in the inflammatory system, and several other math colleagues interested in modeling the control system.
Does your work change how you think about yourself? Do you ever find yourself being conscious of the physics or thinking about your own heart?
Yeah — I do! My physiological colleague became interested in studying cardiovascular control because he fainted when he was young… I have never experienced that but I think it’s interesting to know how the body works. For example, when I go to get my physical check-up and they tell you that your blood pressure is 120/80 I think about the models predicting what is good and what’s bad.
What surprised you the most about being a mathematician?
I don’t know. What I really like about working in academia is that you meet a lot of interesting people who are excited about what they do. I am involved in a project, the Virtual Physiological Rat project, with team-members all over the world including Europe, the US, and New Zealand. Everybody works together to use modeling and simulation to explain physiology. If I was to advise middle school kids, I would tell them to pursue what they think is fun — then they’ll end up doing something that is interesting. And when you dedicate time to a job or a project it often becomes more fun.
If I was to advise middle school kids, I would tell them to pursue what they think is fun — then they’ll end up doing something that is interesting. And when you dedicate time to a job or a project it often becomes more fun.
Did your parents have any annoying rules when you were younger?
There weren’t that many annoying rules. I think I grew up in a time when it really wasn’t very cool to enforce a lot of rules, at least in Denmark.
Did you have any siblings?
And your daughter is also an only child?
Yes. [laughs] My mom was also an only child, so I guess I’m continuing the tradition…
What are some things that you think would encourage middle school students, like your daughter, to think about science or math as a career?
I think it’s important to find good examples that bring the different sciences together. I think one of the reasons why middle school students don’t think math is very fun is because they don’t see enough simple problems that could relate to what they are doing in science. It would be great if you could find more examples where you can link up the science and math — like when they are learning about the heart in biology, or studying genetics. But sadly students don’t have time for extra activities of this kind, since they have to learn what they are going to be tested on.
If you want middle school students to get more excited about what you can do, you can develop computer games… they have good feelings on how to use a computer, but I don’t know how much it is incorporated into the math or science classes. The students who are good at science would probably say that they want to be engineers — they probably don’t really know that they could be math majors. I think the majority of students who become math majors want to go into education and teach. Yet, in applied math, there are so many other jobs you can do.
There are some people who just know from when they are very young what they want to do, and then there are those (like me) who need time to find out what is the right thing to do. Obviously you make choices along your path, but if you’d asked me in seventh grade if I was going to be a professor, I don’t think I would have said yes. I don’t know what I would have said, I really don’t know.
Dr. Mette Olufsen is a professor in the department of Mathematics at North Carolina State University. When she’s not working on applied math problems, she can be found on the sidelines of her daughter’s gymnastics events.