In memoriam: Peter Wittek

Peter Wittek disappeared in September 2019 when an avalanche hit their camp during an expedition on Mount Trishul. Peter was a researcher on quantum computing and quantum machine learning based in Toronto, and is dearly missed in the community.

Shortly before this tragic event, Peter and Vedran Dunjko submitted a perspective article to Quantum Views – a non-review of quantum machine learning. This article offers a last glimpse of his views on quantum machine learning and is a good starting point for those entering the field.

Today, the 17th of March, would be Peter’s birthday. To celebrate his life, we publish the non-review article and testimonials by friends and colleagues. If you knew Peter and would like to add a few words about him, your friendship or collaboration, or his work and legacy, email us and we will add it to this post.


It is difficult to assess how many lives Peter has positively impacted, especially those of colleagues and younger generations of scientists. Over all, I admired his ability to have a clear vision and his determination to make things happen. He was specially good at building bridges where other saw trenches. On a personal level, I will never forget the trust and support he gave me, in and beyond the work environment. I cannot remember a single interaction with him in which he did not transmit me a bit of his characteristic energy and optimism.


I will always have Peter as a role model, and as the scientist I want to become. We miss you, friend.

— Alex Pozas-Kerstjens


Peter was a post-doc in my group and we worked together on several papers. It was a fair deal: he learnt quantum physics from the group and the group learnt a lot of machine learning from him. During this time, I could of course appreciate all his scientific virtues and passion for research. With no doubts, he was a visionary who understood before many the relevance of establishing bridges between machine learning and quantum information. But beyond this, he was a very nice person, who went very well with all of us, and was always ready to share with everyone his views on science, politics, society and any topic of interest. He was sharp and funny. He left plenty of anecdotes that we will always remember with a smile.

— Antonio Acín


A field of science and technology, like every endeavor, is defined as much by its ideas as by its people. I’m proud that Peter is part of ours.


Peter and I met when he was putting together the first Creative Destruction Lab incubator. He had a clear openness and drive for quantum technology to become useful and accessible to more people. I felt that we were fellow travellers, discussing open source and community builting. This led to the first quantum open source workshop at FOSDEM as a collaboration between Unitary Fund and the Quantum Open Source Foundation that he co-founded.


We had so much more that we were planning to do together. His bright vision is missed but not lost. It lives in the many that he drew into the field through his work, support, and spirit.

— Will Zeng


Peter and I first met when I was a research scientist at D-Wave in 2016. I reconnected with Peter when I joined Vector Institute in Toronto and I was excited to hear he had recently joined University of Toronto as an Assistant Professor and as academic director of the quantum machine learning stream at the creative destruction lab. What always struck me most about Peter was his fearless enthusiasm for science, entrepreneurship, and technology. He was unstoppable and had a tremendously positive impact on so many of us. And he was only getting started. He was that unlikely mix of kindness, intelligence, humor, and boundless energy that I am sure we will all dearly miss.

— Juan Felipe Carrasquilla


Peter and I first connected in early 2014 via Martí Perarnau Llobet who was at ICFO and introduced Peter to me. Peter learned that Martí and I were using differential evolution for quantum metrology optimization and Peter became interested in whether artificial neural networks would outperform. From this introduction, Peter and I became collaborators, co-authors of joint papers and friends, bonding over both shared interests in quantum machine learning and a shared commitment to plant-based (vegan) diets.


Barry, Nana and Peter in ShangaiWhen Peter joined the University of Toronto’s Creative Destruction Lab as Founding Academic Director of the Quantum Stream, he encouraged me to join as a Chief Scientist, which I happily did, and I joined Peter as a co-organizer of a 2020 quantum machine learning conference in Banff, where we will share memories of Peter and celebrate his life. I miss Peter’s boundless enthusiasm and creative energy, and I share a photograph of him, me and Nana Liu enjoying dinner, laughter and joy on the Bund in Shanghai.

— Barry Sanders


Peter and I joined the University of Toronto as assistant professors at the same time. I was very happy to find out that there would another junior quantum computing faculty member here, and when I met him in person I was even happier that, not only was Peter working in quantum computing, but he was a wonderful person. He is one of the few people I know who have this rare blend of kindness, humility, humour, but also ambition, vision, intellect, and endless energy. In just the couple of years that Peter has been here at the University of Toronto, he was making many exciting things happening in the quantum computing space, not just in terms of his research but more importantly he was building a vibrant community that fed off of his enthusiasm and optimism. I, and everyone else, was deeply inspired by his example.


On a more personal note, I am deeply saddened by the fact that we were supposed to continue a quantum machine learning project together after he came back from his trip. Although he isn’t around today, my collaborators and I are pushing the project forward; I hope that Peter would be proud of it.

— Henry Yuen


As much as one may try, it is challenging to write even coldest factual sentences about Peter, without having the text sound like a cliche-filled laudation.


Peter Wittek was a pioneer and visionary in the field of Quantum Machine Learning. Certainly one of the first classical machine learning experts to recognize the potential of the synergy between quantum computing and machine learning, he had a vision of bringing classical ML and quantum computing communities to jointly explore this domain. His vision was also his calling, dedicated to ensuring quantum machine learning grows, consolidates and becomes *actually realized*. He has spearheaded virtually every aspect of the domain: scientifically, from developing new quantum-enhanced algorithms, initiating research lines in machine-assisted discovery for quantum systems, by initiating extensive outreach activities, and by co-initiating the largest spin-off incubator program connecting the academia with industry and real world impact. It is not an exaggeration to say that most individuals active in QML, in any function, have had a benefit in interaction with Peter.


On a personal note, I have known Peter since 2015; he was a friend, straight shooter and direct, driven and focused yet open to differing points of view, and above all willing to help. He left us pursuing his passion for mountaineering, where he knew the goal is not in reaching the heights themselves, but in the thrill of the climb, the associated struggle and teamwork. This spirit of wanting to strive is also what our community will continue to do, building on many of his pioneering ideas.

— Vedran Dunjko


Peter and I met more than two years ago in sunny Benasque in 2017 and we have since, until his passing, worked and played closely together in 7 cities over 3 continents across multiple time zones. He was not only a great colleague, but also a very supportive and generous friend. He would always remind me a bit of Peter Pan, having that vitality of life and thirst for adventure, whether it’s creative exploration in research or spontaneously diving into chilly Lake Ontario, despite my persistent protests, to fetch a colony of bryozoa I found. Finally, I can imagine Peter smiling, on top of Everest, declaring that death itself would be another awfully big adventure.


His enthusiasm, playfulness and our endless arguing and laughing over the whiteboard would be greatly missed. We still have so many ideas together that we have not brought fully to light, but I’m grateful that our work combining security and quantum machine learning was completed before he left. Peter also often plays with new ideas on how to bring the community closer together and how to encourage the efforts of younger people. During my last visit to him in Canada, he told me of a wish for a scholarship scheme for students to conduct research in quantum machine learning. As far as I know this was no more than a casual thought at the time. Perhaps this is something we as a community can one day help bring to fruition.

— Nana Liu


With his inquisitive mind Peter has helped shaped this field like few others. Of all people I know Peter deserves most to be called a true cosmopolitan. He saw opportunities to connect where others could only see the gaps – in science and private life. Through his kind character and energizing attitude he has positively influenced the trajectories of many, including mine. You will be dearly missed, as a visionary, as a colleague, as a friend.

— Christian Gogolin


Peter and I, along with his student, Aidan Kehoe and I (Aidan continues work with me), will remember Peter because he was always keen and at the ready to discuss how we might commercialize and build the next generation of machine learning and artificial intelligence on the basis of drawing from the principles in quantum computing to inform classical designs; and, reciprocally, how classical designs could inform the approaches in quantum systems thinking. I worked with Peter at University of Toronto, at the Creative Destruction Lab and I think about him all the time. Our private and group conversations were priceless. He is greatly missed. We will carry on work in his memory.

— Arun Majumdar, Creative Destruction Lab., Technical Advisor