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Themistoklis Sapsis

Themistoklis Sapsis finds himself among the young Greek scientists who have won the admiration of the world scientific community. Within ten years of graduating from the School of Naval Engineering, National Technical University of Athens in 2005, he succeeded in gaining his PhD in Mechanical Engineering at MIT, went on to do post graduate research and in 2016 became Associate Professor in the same department. Recently, his name has become known worldwide on account of his algorithm for predicting extreme events which has opened new doors for world science and given answers to previously difficult issues.  


Associate Professor in the Mechanical Engineering Department, MIT, Massachusetts

He developed an algorithm for predicting extreme events

Can you explain in simple words how the algorithm you developed works in predicting extreme natural events?

To begin with, when we say extreme events, we mean the behaviour of a system which is far from ordinary. The algorithm we have developed looks for situations which lead to extreme behaviour, and takes into account the possibilities that these situations occur in reality. This is done by combining equations with real data or data we receive from a few system tests. In this way, we exclude situations which could cause extreme events, but the probability of it occurring is practically zero.

 Could you give us an example of how the algorithm can be applied on a practical level?

We have already applied it to predicting extreme events in the wave systems of a marine environment. I’m referring to "rogue waves" which occur without warning and in the past have caused major damage to ships and sea platforms. With our partners, we recently completed an experimental study analysing the performance of this method in experimental data using waves created in a wave tank.

Why hasn’t science been able to predict extreme natural events and what are the key factors to remedy this?

The method which we have developed combines two different approaches, dynamics and statistical analysis. We are trying to find precursors which indicate the future occurrence of such extreme events. Depending on statistics alone is quite difficult, as we do not have enough data. On the other hand, depending only on equations can lead us to find "exotic" situations which, if they occur, will give extreme events, but such a probability is zero. What we do is limit this search to situations which could realistically occur, using a new approach to combining  equations simultaneously with the available data or measurements.


This is a historic scientific development hailed by the international community and is a valued addition to the scientific activity of previous years. How do you feel as a Greek abroad who has succeeded in representing the country globally in this way, and how far do you believe the awards you received back in Greece have helped you?

Thank you for your kind words. I think undergraduate studies are among the most critical stages of a person’s education and preparation for this sector. I feel particularly lucky as well as grateful for skills I gained at this stage. Perhaps some of the situations in the Greek Higher Education sector are not ideal, but the passion certain people have and the time they spend is what in the end determines results. After all, this success is one of the many which a graduate from our country can present. So, something does work well in the area of education and preparation and I believe that these are the elements that lead to some admittedly problematic situations being highlighted. This of course depends on each of us, the way it is handled, and whether the focus is on the substance or the detail.


So far, has there been any kind of interaction by Greek scientists? Would you like something like this to happen in the future and how do you think this could be achieved?

I systematically collaborate with a number of Greek scientists. I think travel grants for mutual personnel exchanges (students, researchers, professors) for short periods of time to specifically strengthen such collaborations would be an effective and realistic plan for the further development and cultivation of such efforts.


 What is your opinion of the national initiative ‘Knowledge and Partnership Bridges’? How do you think it will contribute to the networking of Greeks abroad and in Greece?

It is definitely a move in the right direction. This, like any other similar programme, enhances interaction between Greece and Greeks abroad, benefiting both sides and giving mutual insight into the science culture of each. They enrich mutual relationships which ultimately promote progress.


Which actions do you think should be taken to utilise the country’s research personnel, in order to halt the emigration of Greek scientific personnel?

I think that what is missing is a more organised and far-reaching plan. The workforce, the talent and certain infrastructure exist. What is missing is a more organised system to enable a more effective performance. Finding funding is a crucial factor and perhaps, the potential for academic interaction with business/technological efforts in Greece and Europe should be looked at more closely.


Would you like to tell us what your next major scientific target is?

So far, our efforts have centred on predicting extreme events. We want to extend these ideas to the development of algorithms for optimal response and control in engineering systems which exhibit extreme behaviour. The applications we are interested in involve fluid flow interaction with solids and nonlinear oscillation