Four quantum information pioneers speaking at QuSoft event at CWI

On 11 November, celebrated quantum information scientists Charlie Bennett and Gilles Brassard gave a lecture at QuSoft at CWI, being awarded the 2023 Breakthrough Prize in Fundamental Physics. As a surprise, other winners Peter Shor and David Deutsch joined online.

Publication date
18 Nov 2022

On Friday 11 November 2022, celebrated quantum information scientists and longtime collaborators Charlie Bennett and Gilles Brassard joined us at CWI for a special edition of the Qusoft seminar on the occasion of them being awarded the Breakthrough Prize in Fundamental Physics, together with Peter Shor and David Deutsch. Showing themselves as masters of their craft, both Gilles and Charlie gave thought-provoking (and often quite funny) talks. The video of this special QuSoft seminar is now online

Simulation problem

Gilles shared with us his thinking on the so-called “simulation problem”, a popular probabilistic argument that supposedly shows that the odds of us living in a simulation are much higher than you would think. He took us through a mathematically precise version of this argument and then added his own thought, showing that a careful analysis of the computational resources needed for the simulation deflates the original argument, and gives us a decent shot at existing in base reality.

Private classical information

Following this, Charlie took us on a riveting tour of the interplay between physics and cryptography. His goal was to “problematize” the existence of private classical information. This is a foundational concept in cryptography, which is often taken for granted but, as Charlie showed through a series of examples, exists only in an approximate sense, since the laws of physics make it incredibly hard to prevent the leaking of information (although this information leakage will typically be undetectable to all but the most dedicated eavesdropper). He ended with a call to action, arguing that Do-It-Yourself cryptography ought to be preferable to Device-Independent cryptography in a practical setting, precisely because in this DI setting it is very hard to prevent the leaking of classical information after the cessation of the (quantum) cryptographic protocol. 

Finally, co-winners Peter Shor and David Deutsch (digitally) joined the stage, where they explained how they came to work on quantum information theory before it was cool. It turns out Peter, David and Gilles were all originally inspired by Charlie, who was in turn drawn in by Stephen Wiesner, the inventor of quantum money, and also seemingly the progenitor of the entire field of quantum information.

About QuSoft

QuSoft is the Dutch research center for quantum software & technology. Launched by CWI and UvA in December 2015, QuSoft builds on the institutions’ excellent track record in quantum computing and quantum information.

If you are interested in joining QuSoft seminars in the future, you can send an e-mail to Susanne van Dam ( to add you to the QuSoft mailinglist. 

Text: QuSoft. Picture and video: CWI.