**Atlanta, GA**

**What is your research about?**

I work in the field of arithmetic geometry. One type of fundamental problem is finding whole-number solutions to equations such as x⁵ + y⁵ = z⁵, or showing that no such solutions exist. This kind of problem goes back almost 2,000 years to the Greek mathematician Diophantus; hence they are called Diophantine equations.

The idea behind arithmetic geometry is to first consider the space of solutions to the equation in *complex* numbers x,y,z. This space is geometric in nature; for instance, if you squint hard enough, the space of solutions to x⁵ + y⁵ = z⁵ starts to look like a donut with six holes.

One then makes geometric arguments about this space and uses some very deep theorems to derive the properties of the set of whole-number solutions.

Math is worth doing for its own intrinsic beauty and for the subtle understanding about the world that it gives us. Although pure math is not concerned with practical applications, historically it has proved over and over again to be useful in the most surprising and important ways. A recent example is the use of elliptic curves defined over finite fields (an important player in arithmetic geometry) in some of the most advanced encryption algorithms in use today.

**What has been the most exciting time so far in your research life?**

I spend about 95% of my research time writing and revising papers, doing straightforward verifications, or just plain being stuck. The other 5% is where the "aha!" moments happen that make it all worth it.

So far the most memorable time was when I solved my Ph.D. thesis problem. For weeks, I had been thinking hard about the same thing. Then one day, just as I was spreading mayonnaise on my sandwich for lunch, I realized what to do to make the final step work. From there, the solution was like a cascade of dominoes, with everything falling exactly into place. That was not only extremely satisfying. It also launched my career: I was one of the first people to use so-called tropical geometry to solve a problem in arithmetic geometry, which strategy has become something of a cottage industry now.

**How did you find your way to mathematics research?**

My father has a Ph.D. in physics, so I grew up assuming I'd get a Ph.D. as well. I was always interested in thinking about math. For instance, in high school, when I realized I didn't know why the Pythagorean theorem was true, I spent one evening working out a nice geometric proof. Of course this proof had been known since Greek times, but it was satisfying to work something out on my own.

I didn’t get serious about studying math until freshman year of college, when I discovered that I enjoyed my math course more than my physics course.

**What advice would you give to a college freshman who wants to be a mathematician?**

Being a mathematician is both an extremely solitary and a very social activity. Learning, understanding, or communicating mathematics takes a large amount of care and rigor. It is best done alone, with no distractions and with long periods of concentration. But you should also interact with a community of peers, to chat about the most compelling things you’ve learned or thought about recently and to work together when you get stuck, which happens daily.

Take intellectual risks. Sign up for a graduate course even if you’re not sure you'll get an A in it. Go to seminars and expose yourself to concepts you might not understand. Try undergraduate research programs. Never be afraid to tell someone that you’re confused, and ask them to explain something more slowly.

**If you could not be a mathematician, in what line of work would you be now?**

I'd probably be a computer programmer. I've always been good with computers. I learned Basic programming when I was around 12.

**What is the most exciting thing about being a part of Georgia Tech?**

The students. I really enjoy teaching upper-level undergraduate math classes. Some students are extremely hard-working and talented. I derive a lot of pleasure from interactions in class and office hours.

**What are you most surprised about in your encounters with Georgia Tech students?**

Individual students often surprise me greatly. I've had very good students who participate in activities such as professional cage fighting, EMT work in ambulances, cheerleading for a major professional sports team, and serious bodybuilding. I never know what to expect when a new student walks into my office.

**What is an unusual skill, talent, or quality you have now that is not obvious to your colleagues?**

I used to be a very good lindy hop dancer. You can find videos on YouTube. Start by searching for the *Rock Step Lobstahs*.

**What is your ideal way of relaxation?**

The real answer is a movie and a beer, but I’m going to go with jogging. I run about 4.5 miles almost every day, a great way to clear my head. My wife and I just had a baby, though, so all of my routines are up in the air at the moment.

**What three destinations are still in your travel to-do list?**

I have to do a lot of traveling for work, 5-10 conferences all over the world each year. But I would always prefer it if the conference were at Georgia Tech and I could stay at home. So instead of listing places I wish I could visit, I'll mention the three most interesting places where I've attended a conference since I came to Georgia Tech: Fukuoka, Japan; Papeete, French Polynesia; Rio de Janeiro, Brazil.

**If you won $10 million in a lottery, what would you with it?**

I'd put it in low-risk investments and live off the interest. I never particularly wanted to be rich. I'd much rather have stability than wealth, thus my choice to become a tenured professor. That said, with $10 million, I’d have enough income to build an obscenely powerful personal computer, just for kicks.

**Atlanta, GA**

**What is your research about?**

I work on theory and algorithms of graphs. A graph consists of nodes and links joining nodes. Many real-world situations, including social networks and communication networks, can be modeled by graphs.

My current research has two components: basic mathematics research in graph theory and application of graph theory to other areas of mathematics and engineering.

Examples of basic research in graph theory are problems related to the Four Color Theorem, which states: Given a map of countries, one can always color the countries with at most four colors such that countries sharing borders always have different colors. Techniques we developed may be used to solve other problems in graph theory, as well as related problems in theoretical computer science and engineering.

An example of applications of graph theory is a project I'm working on with engineering colleagues about radio-frequency, or spectrum, allocations for wireless communications. We use graph theory techniques to find good solutions to resource allocation problems formulated by engineering colleagues to address the technological challenges in spectrum trading.

Basic math research often leads to results and tools that can be used to solve practical problems or improve the known solutions to practical problems, which could benefit society. For example, our work on spectrum trading took advantage of underutilized communication spectra to make wireless networks more agile and efficient.

**What has been the most exciting time so far in your research life?**

In the past several years, I and several graduate students have been working on an old conjecture in graph theory, called the Kelmans-Seymour conjecture. We recently solved it. The work required some new techniques that will likely be useful for other problems. It will lead to PhD theses for the graduate students involved.

**How did you find your way to mathematics research?**

When I was in high school, I started participating in mathematics competitions and did well in them. So I gradually developed an interest in mathematics.

**What advice would you give to a college freshman who wants to be a mathematician?**

Build a good foundation of mathematics. Try to understand every bit of the details of what you see. Be patient; you may spend several hours (or even days) on a homework problem and not solve it. However, the thinking process itself is a very good mathematical training.

**If you could not be a mathematician, in what line of work would you be now?**

I honestly do not know. Maybe a musician, but I am not sure if I have the talent.

**What is the most exciting thing about being a part of Georgia Tech?**

I am surrounded by outstanding colleagues in mathematics. I can collaborate with engineering colleagues so that what I do in my basic research could be applied to more practical problems.

**What are you most surprised about in your encounters with Georgia Tech students?**

Most Tech students are good at math, want to learn math, and study very hard. I have taught at different places, where most students were not like this.

**What is an unusual skill, talent, or quality you have that is not obvious to your colleagues?**

I play table tennis reasonably well. Some of my colleagues know, some do not.

**What is your ideal way of relaxing?**

Listening to music, reading, and hiking, but I am unable to do so very often.

**What three destinations are still in your travel to-do list?**

Tibet is definitely one of them, but I have not seriously thought about this. Perhaps, I will wait until I retire.

**If you won $10 Million in a lottery, what would you do with it?**

I do not know. I've never thought about it.

**Atlanta, GA**

Thomas is now the recipient of Georgia Tech's highest award given to a faculty member: the Class of 1934 Distinguished Professor Award.

"This award is special because it's from Georgia Tech," Thomas said. "I've been at Georgia Tech for over 25 years, so receiving this award means a lot to me."

The Class of 1934 Distinguished Professor Award recognizes outstanding achievement in teaching, research, and service. Instituted in 1984 by the Class of 1934 in observance of its 50th reunion, the award is presented to an active professor who has made significant, long-term contributions - contributions that would have brought widespread recognition to the professor, to his or her school, and to the Institute. The award includes a stipend of $20,000.

Letters of support for Thomas' nomination came from world-renowned senior researchers familiar with the significance of his work, former Ph.D. students who wrote of his record as a teacher and mentor, and former postdoctoral fellows who praised his ability to develop young talent.

Dean of Tech's College of Sciences Paul Goldbart said, "Robin is a shining star in the international firmament of modern mathematics - a brilliant researcher, inspiring mentor, superb instructor, and treasured colleague. Just today, I had the pleasure of hearing from one of our mathematics graduate students about a glorious contribution of Robin's to the famous four-color problem of map and graph theory."

### Research in Discrete Mathematics

Before coming to Tech in 1989, Thomas worked at Bellcore, a telecommunication research and development company.

"The reason I came here is because Georgia Tech made me an offer I could not refuse," he said. "I was technically working in industry, but, in reality, I was also doing my own research. So, in that sense, the research part was not that different."

Thomas' research in discrete mathematics is concentrated in the fields of graph theory and combinatorics, areas with applications across a wide span, from engineering and computer science to economics, biology, and social science. The issues being researched are often motivated by real-world problems in telephone network design, airline scheduling, online auctions, and Internet design and searching. Many of the problems solved by Thomas and his collaborators were open for several decades and had successfully resisted the best efforts of the world's leading researchers.

Thomas also is director of Tech's Algorithms, Combinatorics, and Optimization (ACO) program, an interdisciplinary Ph.D. program linking the College of Computing, the School of Mathematics, and the H. Milton Stewart School of Industrial and Systems Engineering. About half of ACO's Ph.D. students go into academia and the others go into industry.

Thomas has graduated 16 Ph.D. students at Tech, and he has been an informal advisor to many others.

In receiving the Class of 1934 Distinguished Faculty Award, he joins ACO colleagues Dick Lipton (Computer Science) and George Nemhauser (Industrial and Systems Engineering), who were honored with the award in 2012 and 2015, respectively.

### Persevering with ALS

In 2008, Thomas was diagnosed with amyotrophic lateral sclerosis, also known as ALS or Lou Gehrig's disease. The disease is characterized by stiff muscles, twitching, and a gradual decrease in muscle strength, resulting in difficulty speaking, swallowing, and eventually breathing.

"It's a progressive disease, where I'm gradually losing the use of my legs and other functions," said Thomas, who uses a motorized wheelchair to get around.

"I had to completely change the way I deliver lectures," said Thomas, who is on faculty development leave this semester, but usually teaches Applied Combinatorics (Math 3012) and Graph Theory (Math 6014). "I can no longer stand in front of a whiteboard. At first, I was writing my lectures on paper and using a document camera to project it onto a screen. But that's no longer possible."

Now, Thomas prepares his lectures in advance, which he says is both good and bad.

"It's good because students get to see the material ahead of time. They can print it and bring it to class. The bad thing is that I have to anticipate the students' questions. So I design my lectures where I ask the questions for them and then reveal the answers."

Of course, Thomas cannot anticipate every question. When a student asks a question that he did not expect, he answers it and asks for a student volunteer to write the answer on the white board. He also has a teaching assistant to help him prepare for class.

Although Thomas' body is failing him, his mind remains sharp and focused.

"There are lots of ongoing research projects that I would like to finish," he said. "In terms of career moves, I don't have any aspirations to be a department chair or anything similar. I'm quite happy with running the ACO Program."

Thomas, center, is pictured with his advisor and some of his former students at a conference held in his honor in 2012. The Conference on Graph Theory took place at Georgia Tech to ce

**Atlanta, GA**

### What is your research about?

My research involves using mathematics to understand human behavior and has largely focused on criminal behavior. I try to use math to help predict, solve, and defend against crimes. This research has led to tangible societal benefits, including a software program now in use by several police departments, including Atlanta's, that helps police better predict where crimes may occur today

### What has been the most exciting time so far in your research life?

The most exciting time was probably when I was still a young graduate student and everything was so new. I still remember when my first paper was accepted for publication: It gave me a huge sense of validation and served as a tangible symbol of my entrance into academia as a researcher.

### How did you find your way to mathematics research?

My path to mathematics research was not direct, as my degrees are all in physics. But the division between physics and applied math is a bit blurry, and given my own research interests, math made a bit more sense. So after obtaining my PhD, I went to the UCLA math department for my postdoc, and have been in math since then.

One early influence that led me on this winding path was watching Carl Sagan's Cosmos when I was a child. I still remember being in awe of the idea that you could explain the universe through equations. I knew at that time that I had to be a part of that.

### What advice would you give to a college freshman who wants to be a mathematician?

I would advise them that mathematics is a huge field and that they should explore all the possibilities that being a mathematician can bring. They might end up really liking very pure, abstract math, or more applied topics. And they should explore all the future careers that can be had with a mathematics degree, outside of the obvious track into academia.

### If you could not be a mathematician, in what line of work would you be now?

The answer depends on whether we are constrained to reality, or I'm allowed to give a more fanciful answer. I could simply say that I'd be a physicist, and my job would not be much different. If I'm allowed to dream, I would probably choose to be an author, as I've always loved reading and writing creatively. Or maybe a chef, because I love food and cooking.

### What is the most exciting thing about being a part of Georgia Tech?

Just the atmosphere at Tech is so exciting. The students are all so great and motivated, and the research here is really cutting edge. Georgia Tech is a really positive place.

### What are you most surprised about in your encounters with Georgia Tech students?

The students here have really great attitudes toward learning and take that with them to the classroom. This always surprises me, pleasantly, as it is not generally true across all campuses.

### What is an unusual skill, talent, or quality you have that is not obvious to your colleagues?

I enjoy working with my hands, and I am a competent handy man around the house. I've done various things around our home, from re-plumbing our swimming pool, to installing a top-mounted chimney damper, to building raised garden beds.

### What is your ideal way of relaxing?

I enjoy just lying on a raft in my aforementioned pool on a warm summer day, listening to the breeze whistling through the trees and the chirping of birds. Throw in a nice cold beverage and I'm all set. For me, relaxing often means turning off my brain for a while so that it can recharge. I think I have been able to strike a healthy balance between work and leisure, so that I don't feel starved for relaxation.

### What three destinations are still in your travel to-do list?

One nice perk of being an academic is that you get to travel a lot, so that many places that were on my list have been crossed off by now. I would like to visit a South Pacific island, like Tahiti, for obvious reasons. I love trying new foods that are unconventional, at least to a Western palate, so enjoying some food tourism in a country like Thailand or Vietnam would be great. Finally, I'd really like to visit Ireland, for the beautiful green countryside and the pubs.

### If you won $10 Million in a lottery, what would you do with it?

I'm not really into possessions as much as experiences, so I don't think I would go nuts buying huge homes or elaborate automobiles. After setting aside money for my daughter's future and for retirement purposes, I'd use the rest to fund travel and dinners at amazing restaurants, things of that nature. I'm somewhat miserly, so I doubt I would run through all of that money in my lifetime.

**Atlanta, GA**

### What is your research about?

I am fascinated by analogies. Much of my work involves so-called "p-adic" numbers, which are analogous to real numbers like 2 or π, but with important differences. For example, in p-adic geometry, every triangle is isosceles! This world might sound exotic and useless, but p-adic numbers play an important role in modern life, including cryptography, which is the making and breaking of secret codes.

A lot of things in mathematics appear to have no applications, but in fact, down the road, they turn out to be incredibly useful.

### What has been the most exciting time so far in your research life?

In 2006, Georgia Tech postdoc Sergey Norin found a clever solution to a problem one of my undergraduate research students had been working on. Building on Norin's solution, he and I soon proved a Riemann-Roch theorem for graphs. This theorem is another mathematical analogy, between graphs, which you can imagine as being like websites and the hyperlinks between them, and "Riemann surfaces," which are classic geometric objects from the 19th century.

The Riemann-Roch theorem is used widely, from error-correcting codes to string theory. Norin and I were the first mathematicians to realize that it has an avatar in the world of graphs. The resulting paper is now my most cited work.

### How did you find your way to mathematics research?

In middle and high school, I loved reading recreational math books by Martin Gardner. Many mathematicians of my generation got interested in the subject from his writings. A conference called Gathering for Gardner takes place every two years in Atlanta.

During my senior year in high school, my first-ever mathematics research project placed third place in the 1990 International Science and Engineering Fair. The project helped get me a full scholarship to the University of Maryland, College Park, where my professors encouraged me to pursue mathematics as a career.

Although I wanted to be a math major, for a while I considered double majoring in physics, history of science, or poetry. I decided to focus on math. It was actually difficult for me to make the transition from being a "polymath" to a "mathematician."

### What advice would you give to a college freshman who wants to be a mathematician?

Master the fundamentals. You have to be able to understand and write rigorous proofs to be a mathematician, and it takes a lot of discipline to do this. Expose yourself to different kinds of mathematics, and try to get some research experience as an undergraduate.

### If you could not be a mathematician, in what line of work would you be now?

I'd be a professional magician. I've been interested in magic my whole life, but I never seriously considered doing it as a full-time job. I doubt I'd be good at the business end of it.

### What is the most exciting thing about being at Georgia Tech?

I love the fact that the overwhelming majority of students are not only really good at math, but they appreciate its value for whatever they're studying. Students want to be in my class to learn, rather than attending only because it's a requirement. That's a great position to be in as a professor. When students want to learn from me, I'm much more motivated to give them something really valuable.

### What are you most surprised about in your encounters with Georgia Tech students?

I'm surprised that those who are so good at mathematics resist the temptation to major in it. Seriously, math just literally sucked me in -- I was so fascinated by its elegance and mystery.

### What unusual skill, talent, or quality do you have that may not be obvious to your colleagues?

My colleagues know about the magic. They may not know that I sang in a highly regarded a cappella group in the University of Maryland, College Park; or that in 1990 I won a national poetry contest sponsored by the National Holocaust Foundation; or that in 1995 I was a contestant on Jeopardy! I came in second, but the guy who beat me went on to win the Tournament of Champions that year.

### How do you like to relax?

Hmm, I'm not sure what you're talking about.

Seriously, most of my downtime now I spend with our 6-week-old baby. That's not always relaxing, but it's what I want to do when I'm not working. It's great for taking my mind off work.

### What three destinations are still in your travel to-do list?

I'd like to visit southeast Asia (Vietnam, Cambodia, Thailand). I love the food, and I admire the politeness and respect for tradition in their culture. I'd also like to see Iguazu Falls, on the border between Brazil and Argentina, and Victoria Falls, on the border between Zambia and Zimbabwe. I'd explore the Amazon as well, but I hate mosquitoes. And I'm afraid of crocodiles.

### If you won $10 Million in a lottery, what would you do with it?

Put it toward my kids' college education. I'd also buy my wife some really nice jewelry, as a gesture of thanks for reviewing my responses to these questions.

Note: the image above was taken in June 2015, when Matt Baker brought his "Mathemagical Mystery Tour" to more than 100 members of the Atlanta Science Tavern in Manuel's Tavern.

**Atlanta, GA**

### What is your research about?

The world intrinsically contains multiple scales, and one theme of my research is to develop theories and algorithms that help us understand how different scales interact.

One classic example is the following astronomical problem. It is well known that planets rotate around their host star due to mutual gravitational attraction. For instance, Earth finishes one period of rotation around the Sun in exactly one year. Pairs of planets also experience mutual gravitational attractions, but such interactions are much weaker and the immediate effects are not obvious, especially if one considers only hundreds of years in the stellar system.

Nevertheless, the sun burns for billions of years, and over this much larger timescale, microscopic planet-planet interactions do accumulate. The question is, Will this accumulation lead to large changes of the planet orbits? Or more generally: How do small-scale details cascade to large scales?

Quantifying such cascades across scales is critical for many important questions, such as, Will Earth keep its current distance from the Sun and maintain its nearly circular orbit, both which are essential for sustaining the climate that fosters current life forms? Where was Earth when it formed billions of years ago? Can we predict the existences of planets outside the solar system, given that we can only see stars but not planets, due to planets' small sizes and faint luminosities? Will these so-called exoplanets be habitable?

Applications are not limited to the sciences. For instance, we have been using fast oscillations (e.g., laser) to control slower engineering systems. In this sense, my group addresses both scientific curiosity and engineering practicality, and that is one thing I enjoy about developing general methodologies.

### What has been the most exciting time so far in your research life?

When scientists, engineers, and I collaborate, we always iterate many times to carefully formulate the problems, solve the core difficulties, and interpret the results. It is also the case when I work on mathematical proofs. Serendipity seldom happens to me; what happens more often is many solid little steps. All I do is prepare myself by thinking constantly, so that whenever good things happen they will not be missed.

### How did you find your way to mathematics research?

Like many kids, I participated in informatics and mathematics Olympiads, which I found enjoyable. Such enjoyment may not be practical, as the competitions are serious and require significant training. I never qualified for the national teams to compete internationally, but my life has been positively changed.

In addition, my father, even though he was working in a non-STEM discipline, had an amazing curiosity about physics, and he motivated me by asking questions – such as, What are quarks made of? – when I had just learned to spell my name. Those questions sparked my life-long interest in how things work at microscopic and macroscopic levels. Therefore, it is a great pleasure to work in applied and computational math, as it provides a good blend of mathematics, informatics, and physics.

### What advice would you give a college freshman who wants to be a mathematician?

Behind abstractness, there is almost always intuition.

### If you could not be a mathematician, in what line of work would you be now?

In the financial industry, because of my interests in probability and differential equations; a programmer because of my experiences with algorithms; a professional gamer because of my playful nature; or house husband because of my ever-expanding to-do list of house work.

### What is the most exciting thing about being a part of Georgia Tech?

Everyday Im discovering new exciting things, but so far what I have enjoyed the most is that Georgia Tech is one of the best technology schools, where stellar scientists, engineers, and mathematicians are just doors away, open to engaging discussions. I have equally enjoyed working with the wonderful students, who are positive, modest, eager to learn, and contributing to a lively campus life.

### What are you most surprised about in your encounters with Georgia Tech students?

Given how good a university Georgia Tech is, the students are really modest and objective. Teachers should of course always try to teach as well as they can. But sometimes students do not try hard enough to learn, and whatever they cannot learn is the teacher's fault. This blaming of the teacher seldom happens here; instead, the relationship between students and teachers is generally healthy, with objective mutual feedbacks promoting quality education.

### Tell me about an unusual skill, talent, or quality you have now or in the past that is not obvious to your colleagues.

I normally don't sing out of tune.

### What is your ideal way of relaxing?

I enjoy many common ways of relaxing, except for drinking alcoholic beverages. Because I cannot work more than 10 hours per day in a sustainable way, I do relax quite often.

### If you won $10 Million in a lottery, what would you do it?

One part of my research is on rare events modeling and simulation. I, like many others, claim that small- or zero-probability events will never happen. Consequently, to characterize these nevertheless important events, it is necessary to conduct extra analysis and design biased algorithms. Winning the lottery would shatter my research premise, and therefore I would mourn for a while. Then I will secretly invest the money.

**Atlanta, GA**

### What is your **research** about?

I've been all over the place in terms of research. In fact, majority of my publications have been outside of mathematics proper - in electrical engineering (network theory), physics (quantum mechanics and fractals), operations research (optimization, games), education (cross-disciplinary learning, MOOCS), etc. My latest paper was with a student on nuclear engineering. What ties these research activities all together is that the problems involve a combination of discrete mathematics, matrices, and computers. I find much of mathematics all by itself to be sterile and too inward-looking.

### What has been the most exciting time so far in your academic life?

Working with really good students even before they get to Georgia Tech. Through the Distance Calculus Program I started teaching in 2005, high school students in the Georgia Public School System have been able to take college credits for courses in calculus. Using audio or video links, they take the courses at the time I teach them in Tech, and they take the same quizzes and tests that I give to on-campus students.

The program now serves close to 500 high school students per year. It enables public high schools to teach college-level courses at low cost. Almost all of the students in the program apply and are admitted to Georgia Tech, making up 6-7% of the freshman class when they get here. I'm very proud of that. (More information about the Distance Calculus Program is on pages 14-15 in Volume 8 of *Proof Reader*.)

### How did you find your way to mathematics research?

It was either mathematics or music. I had a really great seventh-grade math teacher. Also the wonderful math faculty at University of Maryland were incredibly helpful and supportive.

### What advice would you give to a college freshman who wants to be a mathematician?

Do the mathematics that you enjoy and have fun with it.

### If you could not be a mathematician, in what line of work would you be now?

A musician.

### What is the most exciting thing about being a part of Georgia Tech?

The students are really great. They are not just good at science and technology. They do wonderful things that are not graded or even required in class. Riding bicycles, making music, building things.

### What unusual skill, talent, or quality do you have that is not obvious to your colleagues?

I play (in public) at least a dozen instruments. In college I was a piano player in a blues band; these days I play jazz standards on piano (from an ipad!). I play lots of "stringy things" - double bass, electric bass, guitar, mandolin, octave mandolin, mandocello, ukulele, etc. I play baroque and modern flute, and a whole bunch of renaissance woodwinds you've never heard of. Sometimes you can catch me on campus at the Wesley Foundation on Tuesday evenings. (For more of Tom Morley's musical interests, visit Tom Morley's facebook page.)

And I once taught an entire semester course on the Rubik's Cube.

### What is your ideal way to relax?

Riding a bicycle with friends, and sprinting up some of the steep hills in the Atlanta area.

### What three destinations are still in your travel to-do list?

County Kerry Ireland, where I have some second cousins; Nepal, just for fun; and Spain for the architecture and food.

### If you won $10 Million in a lottery, what would you do with it?

Commission a builder I really like to build a five-string double bass in the style of Abraham Prescott's 19th-century basses, build and equip a personal recording studio, and then give lots of it away.

**Atlanta, GA**

### What is your research about?

I am a probabilist, a mathematician studying probability theory - a specialist of the study of chance and randomness. Because we do not really have a definition of randomness, it might appear, at first, contradictory to try to have a mathematical theory dealing with something that is undefined. But everyone has some intuition about randomness.

When flipping a fair coin, the outcome cannot be predicted with certainty, but a couple of assumptions are reasonable. First, one expects to get on each flip either a head or a tail with equal probability. Second, one expects that when flipping this same coin a very large number of times (say 10,000 times) one would approximately get 5,000 heads and 5,000 tails.

Both assumptions are reasonable. The first is a case of the use of postulates. The second is based on a theorem now called The Law of Large Numbers. This general theorem was proved only in the 20th century, some 250 years after the proof of its first particular case. Nowadays in popular culture, aspects of something called the "wisdom of crowds" is nothing but a manifestation or application of The Law of Large Numbers.

There is a general level of misconception about probabilists. First and foremost, they are mathematicians whose goal is to prove theorems - and not to compute the odds of winning the lottery. These theorems might not be at all motivated by real-life problems. Probabilists are in that sense closer to "pure" mathematicians than to "applied" ones.

However, because randomness is part of life, some theorems are motivated by real-life applications or by physics, statistics, other sciences, or engineering. Moreover, probability theory is widely applicable: Former students of mine who are not university professors are designing mathematical models for finance in Wall Street, computing the odds and designing casino games, or trading energy options.

I have, myself, some interest in such applications. I have done research in mathematical finance and also proved theorems having potential consequences in bioinformatics. In each case, what was crucial was the unity, the power, and the reach of the mathematics of probability theory.

### What advice would you give to a college freshman who wants to be a mathematician?

This is a unique time and opportunity for you, a time of freedom. Explore, learn as much as possible, take risks, follow your intuition, your passion, and do not worry about where it is going to lead you.

### If you could not be a mathematician, in what line of work would you be now?

Maybe an oenologist, since I have throughout the years developed a knowledge of various aspects of viniculture.

### What unusual skill, talent, or quality do you have that is not obvious to your colleagues?

I have judged high-level coffee/barista national championships.

### What is your ideal way of relaxing?

Drinking some good wine with some good friends.

### What three destinations are still in your travel to-do list?

I do not have such a list.

### If you won $10 Million in a lottery, what would you do with it?

I have never played the lottery.

**Atlanta, GA**

### What is your research about?

I work closely with biologists to combine mathematical modeling with experiments. We study how populations of bacteria grow and evolve, as well as the dynamics of bacterial killing by antibiotics and viruses, especially in physically structured environments such as biofilms.

Physically structured habitats are particularly critical for treatment of surface-associated infections, such as endocarditis, osteomyelitis, and infections of prosthetic heart valves and joints. Our goal is to improve the efficacy of antimicrobial therapy.

I am also the principal investigator of the Boeing-sponsored FlyHealthy™ research study, whose goal is to understand the rates and routes of transmission of infectious diseases in an airplane cabin during flight and to find strategies to mitigate transmission.

### What advice would you give to a college freshman who wants to be a mathematician?

Do a minor in an exciting area of science, engineering, or finance. A minor will help you develop a foundation of knowledge in another field, to see how mathematics is used in applications and to learn new mathematical methods. Almost everything I know about numerical approximations and special functions I learned in physics classes.

The minor would also provide a basis for future multidisciplinary collaborations, which I enjoy immensely. Also learn to program well in at least one computer language, and take at least one intensive writing class.

### What is the most exciting thing about being a part of Georgia Tech?

A huge amount of exciting research goes on at Tech, and almost everybody uses, or at least appreciates, mathematics. This environment leads to many exciting collaboration opportunities across campus.

### What are you most surprised about in your encounters with Georgia Tech students?

I am continually surprised by their cleverness and excellent work ethic.

Just yesterday I met with an undergraduate who started a research project with me on animal movement. Two weeks ago I sent him a video of the movement of a deer that a wildlife biologist colleague created from GPS tracking. On his own initiative, the student extracted the essential data from the video, taught himself the basics of Markov chains, and constructed a Markov chain model. Wow!

### If you could not be a mathematician, in what line of work would you be now?

I hated biology in high school and college, because it was taught to me as completely descriptive, with no quantitative element. Biology has since become much more quantitative, and mathematical models have provided many important insights to biological phenomena. If I could not be a mathematician, I would probably enjoy being a microbiologist, a geneticist, or a virologist.

Shown on the right is a competition robot built by robotics team that Howie Weiss mentors.

### What unique skill, talent, or quality do you have that your colleagues may not know about?

I have a robot shop in my basement.

Members of my entire family are big supporters of FIRST Robotics Competition (FRC) in Dekalb County schools. When my older daughter, Kristin, was in high school, she competed in FRC, which involves building and programming robots up to 120 pounds. Now a Georgia Tech sophomore, she mentors Dekalb County's only FRC team.

My younger daughter, Zoe, has competed on Dekalb County's only FTC (FIRST Tech Challenge) team these past three years. We have been hosting her team in our basement, complete with a 12 ft x 12 ft playing field. Previously, she participated in FIRST LEGO League (FLL) robotics. In FLL, children in grades 4-8 build and program autonomous robots using LEGO Mindstorms components and compete in a yearly themed playing field.

Most Dekalb County elementary schools have an FLL team, but very few teacher-coaches have any technical background. My wife, Lora; Zoe; and I spend Friday evenings in the fall traveling around to Dekalb County schools to help run hands-on FLL workshops. We also judge at the local and state tournaments.

### What is your ideal way to relax?

I enjoy outdoor activities: paddling along local rivers, hiking, and biking with my family. I also ran for much of my life, and after a (too) long hiatus, I have resumed running.

### What three places would you like to visit?

Certainly the Galapagos Islands.

Several years ago I wrote a paper on inverted biomass pyramids at some pristine coral reefs in the middle of the Pacific, and in principle, I would love to explore one or two of these reefs. In practice, this would likely require weeks on a boat in the open ocean - I get queasy just thinking about this - and then diving with aggressive sharks.

Finally, I would like visit Tromsø, located above the Arctic circle, to observe the Northern Lights and give a talk in the world's northernmost university. I know a few excellent scientists who work there.

**Atlanta, GA**

Georgia Tech's BS DMTH alumna (2011) Michelle Delcourt is now a graduate student at the University of Illinois at Urbana-Champaign. She recently received the Graduate Student Leadership Award from the university's Graduate College. This award is sponsored by The Graduate College and its student advisory group, SAGE (Students Advising on Graduate Education). It was created to recognize graduate students who have exhibited outstanding service that has positively impacted the campus or wider Urbana-Champaign community.

Through her work with two math department organizations – Illinois Geometry Lab and Association for Women in Mathematics, Michelle has demonstrated exceptional leadership skills. She single-handedly pioneered and raised over $25,000 for the Sonia Math Days for Girls and Girls Engaged in Mathematics and Science (GEMS), wherein she created extremely successful workshops that have affected the lives of many young girls by introducing them to beauty within deep mathematics. Her work has led to ongoing partnership with Chicago Preparatory Science and Engineering Program that provides non-traditional learning opportunities in math and science to some of Chicago’s most underserved populations.

Now, a 5th year PhD candidate, she uses her love of math and art to engage young girls and underrepresented minority students in math through community outreach programs. She hopes that her approach could help attract students who might not otherwise choose mathematics. The Graduate Life blog has a nice article about Michelle.