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Once a physicist: Jaan Tallinn

Jaan Tallinn is one of the founding engineers of Skype and a co-founder of the Centre for the Study of Existential Risk and the Future of Life Institute.

Jaan Tallinn

Why did you decide to study physics? I'm actually a computer programmer first and physicist second. I started programming in my early teens, but I had a really great physics teacher in high school, so I and my good friend and classmate Ahti Heinla, who ended up being the chief technical architect of Skype, decided that okay, we already know everything about computers, so let's broaden our horizons a little. I really liked the first year of university, when the courses I took basically demolished high school physics and rebuilt it properly using calculus. Starting from the second year or so, though, I came to realize that there was a pattern in solving physics problems: you build this wonderful differential equation, and then you say "Oh, you can't solve it, so let's put it in a Taylor sequence and look at the first one or two terms." My taste in mathematics was a little bit hurt by that I really appreciate preciseness and elegance.

How did programming become your passion? It's a bit hard to say, actually, because I don't fully remember I started very young! But one nice thing about programming computers in the 1980s was that computers then were really slow, so they didn't do much, but at the same time, you could see they had enormous potential. That meant you could write some very simple programs and still get the computer to do interesting things. Today, when computers are a million times faster than they were in the 1980s and YouTube is just one click away, I have a very hard time convincing my kids to take up programming because it's so demoralizing.

What did you do after your physics degree? Ahti and I had started a computer games company before we went to study physics, so basically, I started programming games before I went to university, I programmed games during university and then I continued programming games until the end of the 1990s. Then our US games publisher, Interactive Magic, went bankrupt, and we took a step back and thought, okay, let's see what other programming tasks are out there. We ended up programming an Internet portal where Niklas Zennström, who later became the CEO and the main founder of Skype and Kazaa, was the CEO, so that's how we met Niklas and his co-founder Janus [Friis] and started working with them.

How has your physics background helped? For me it is hard to untangle the influences of physics and programming. They are somewhat correlated. But sometimes I say that the most valuable thing about programming is that it gives you an intuitive sense of what it means to have your thoughts fully specified, and I think physics gives you a similar sense. Also, a big thing that I am working on now relates to the so-called "existential risks" that pose a threat to the survival of the human species. The institutes I co-founded are trying to figure out what humanity should do about technological existential risks, and in these institutes there is a massive over-representation of physicists.

What are the biggest existential risks? The two big categories are natural existential risks (such as asteroids, comets, supervolcanoes and eventually the Sun's expansion) and technological existential risks. The second category includes things like biological risks, especially from synthetic biology; my speciality, artificial intelligence; and geoengineering. The nice thing about natural existential risks is that we have lived with them for a long time and they are not necessarily increasing or decreasing, in terms of magnitude. But we are sailing into uncharted territory with technological progress this century, and there might be really devastating side effects from that.

What else are you working on now? I have a portfolio of more than 30 companies that I have invested in, and a couple of them I follow very closely. The one on the top of my list right now is a company named Fleep. It is developing a new kind of online messaging product that can inter-operate with e-mail, so if you want to communicate with someone, instead of having to convince them to join your messaging platform of choice, you can use Fleep and communicate with them over e-mail. This actually dates back to my Skype days, when I was a big proponent of Skype's instant messenger service (IM), but the company was always focused on voice and video (and rightly so), and that meant the IM portion didn't get a lot of attention. So when a bunch of really good Skype engineers decided to leave and start building an IM product, I was very interested.

Any advice for current physics students? I think that physics is a great choice of subject to study, because with the increased automation that we are going to see, there will be significant pressure on jobs that are more specialized. So if your education supports a diverse set of potential careers, you are in a much stronger position in that changing landscape of professions.