Frontiers Science Hero: Alex Hansen from Frontiers on Vimeo.

Prof. Alex Hansen has always been fascinated with problems. “As you get older you begin to find out that problems are wonderful,” he said. “You do not have to look into the galaxy to look for problems; you can see them right in front of you. I feel, quite literally, down to earth with my field of research.”

Prof. Hansen earned his Ph.D. from Cornell University in 1986. He has been professor of physics at the Norwegian University of Science and Technology in Trondheim, Norway from 1994. Hansen is member of the Norwegian Academy of Science and Letters, the Royal Norwegian Society of Science and Letters and the Norwegian Academy of Technical Sciences. He was awarded an honorary doctorate (Dr. h. c.) by the University of Rennes in 2009. Hansen has chaired the Commission on Computational Physics (C20, of IUPAP) and acts as a vice president for the International Union of Pure and Applied Physics. He is also the Field Chief Editor for Frontiers in Physics.

Without his curiosity Hansen would not be where he is now. Without curiosity the world would be, in his words, “terrible”. His research and need to discover has been fueled by his admiration of science heroes. “You read about the science heroes who went out to discover, and suddenly had a moment where they understood something no one else did. Those are my kind of heroes,” Hansen admitted.

Surface, sound and liquid

For Hansen the problems lie right in front of every person’s eyes. His scientific discoveries and research focused on the most simple every day aspects we tend to oversee. Everyone has had a paper in their hands, tore it apart and threw it in the bin without having given it any second thoughts. The most meaningless actions for us are the most meaningful for Hansen’s research.

“The one research problem I worked most on is the roughness of fractured surfaces. You take a material, for example a piece of paper, you tear it and you look at the surface afterwards. Then you think about why it looks like this,” he explained. Hansen did not restrict himself to surfaces but also to sound waves. “If you crack something you hear the sounds *crack crack crack* to understand the statistics of these sounds. Avalanches were part of the research I conducted in relation to sound. We used fracture as a model system for that.”

Another area of research includes experiments with porous objects, such as a sponge. “If you fill with two liquids that do not mix, they will start to compete for the same space and push each other around. We tried to understand the dynamics of this process and how these liquids compete. These experiments are close to what we see every day,” he explained.

The importance of children in science

The ultimate motivation for Alex Hansen lies in his curiosity. He is particularly fascinated by the first outcome of an experiment The most important words in sciences are according to Hansen: “Hmmm, that is interesting” or “I did not expect that, why did that happen?”. He further added that the contribution of children in science is essential and of great importance when it comes to asking questions and the need for new knowledge.

“It is amazing how twelve years old kids come and ask questions, as many are actually very deep questions. They are questions I think about even hours after they have been asked. This is the amazing thing about science; people who are not in a scientific field think everything has been discovered. But there are so many small, nearly invisible problems right in front of us that need to be thought about,” he said.

We only know half of what we think we do

The field of Physics is big and full of undiscovered mysteries. Hansen say believes the main research focus is in industries related to physics is porous media. “In a lot of industries, all problems have to do with water transport and water to the world. This is an engineering field usually. We face the problem of developing a correct description of motions of liquid in porous media from the smallest scales up to large kilometer scales, which do not exist yet. Engineers think they have it, but they got it wrong,” he stated.

Another important aspect that Hansen pointed out is our bridges and streets which we cross daily on our way to work or school. “The connection with fractures is important,” he said. “We are trying to understand the deterioration of materials and of course what keeps buildings up. You can see the progress that has been made over the past one hundred years. Today bridges are elegant, stable and the straps are very thin, in old times they were thick. That is the progress we are seeing and it will become even better, especially material wise we are constantly improving,” Hansen elaborated.

Collaboration in science and Frontiers

The subject of publishing as well as collaborating in science as a whole requires disciplinary cross over in fields. Hansen believes that all the fields he has mentioned have a close cross disciplinary aspect including physics as well as other fields. There are thousands of engineers working on construction sites simply because humans have the need to build and construct the world. Without this collaboration and team work none of it would be possible.

With this rapid development of cross disciplinary researches technology had to catch up as the want for innovative constructions became more evident in society. “I see that computers are going to be more important,” Hansen identified. “In the past you did experiments where you would use a pen and paper to understand them, but now you can build your own world with a computer. You can test your ideas directly and that is a completely new way of doing science. It is moving enormously fast now and that is changing the field completely.”

You can follow the work of Alex Hansen on the Frontiers Research Network (Loop).

Recent published papers:

Discrete Element Modeling of Brittle Crack Roughness in Three Dimensions

Grand Challenges in Interdisciplinary Physics

Upcoming papers:

Dynamic wettability alteration in immiscible two-phase flow in porous media: Effect on transport properties and critical slowing down [In review]