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At BEIT, our mission is to push the boundaries of quantum computing for drug discovery - and part of that involves making sure the quantum technologies we rely on are both powerful and trustworthy. We’re delighted to highlight our team member Grzegorz Rajchel-Mieldzioć, who recently traveled to ICFO (The Institute of Photonic Sciences) in Barcelona to present his latest work on quantum channel certification. The research, titled “Spoofing of Quantum Channels Enables Low-Rank Projective Simulation,” was carried out in collaboration with Timothy Heightman and is supported by the European Innovation Council (EIC).

Quantum channels are essential processes that carry or transform quantum information. As these technologies advance and move into noisy, real-world settings, verifying that a quantum channel does what it claims - especially when measurements are limited - becomes a major challenge. Grzegorz’s talk centered on a striking phenomenon: under typical, restricted measurement protocols, a provider could “spoof” or imitate a high-performance channel using a simpler one. In other words, if users only test limited outcomes, they might never realize they are paying for a resource-intensive channel but receiving something less expensive to produce.

Such impersonation hinges on different channels producing identical measurement statistics for the same restricted set of tests. Grzegorz’s study meticulously pinpoints how and when one channel can masquerade as another, unveiling equivalence classes of channels that share the same observable outcomes under standard projective (von Neumann) measurements. Crucially, the research demonstrates how low-rank representations of quantum channels - those requiring fewer internal parameters - can still match the key signals that these limited tests look for. This creates an obvious vulnerability in any setting where users cannot afford to implement a fully exhaustive certification procedure.

Rather than sounding only an alarm bell, Grzegorz also presented possible ways to counter this. By expanding the range of measurements or scrutinizing different statistical properties (even a handful of carefully chosen averages and variances), one can create a certification scheme that forces the quantum channel to reveal its complexity. In the near future, we will explore how using low moments across multiple measurement bases can make it harder for a low-rank impostor to pass as a genuine high-rank channel. This approach offers an efficient path forward - rather than testing every possible scenario, a user can strategically look at just enough data to unmask the simpler channel trying to hide among more complex ones.

These findings come at a critical time as quantum computing services increasingly move to the cloud. In a future where organizations access quantum hardware remotely, it becomes vital to have robust verification mechanisms for the integrity of those devices. No one wants to invest in cutting-edge quantum capabilities only to discover they were provided with a cheaper substitute. The methods Grzegorz discussed - including a Sinkhorn-like algorithm to find the minimal, “spoofing” Kraus rank - provide both a blueprint for understanding how these scams can be orchestrated and a roadmap to prevent them. This work represents an important step in building confidence as we scale to fault-tolerant quantum computers.

For BEIT, this research aligns perfectly with our broader goal: harnessing quantum computing to revolutionize drug discovery while ensuring that the underpinning quantum infrastructure is worthy of trust. Every step of a quantum calculation - from data preparation to final readout - must be reliable if we are to turn groundbreaking simulations into effective therapeutic discoveries. Thanks to support from the European Innovation Council, Grzegorz and our team can continue exploring how to reinforce these verification protocols, ensuring that we remain at the forefront of reliable quantum technologies for the pharmaceutical industry and beyond.

Grzegorz’s presentation at ICFO made a strong impression among attendees and underscored the importance of diligent quantum certification work. We look forward to sharing further updates on this project as it continues to evolve, and we invite everyone - scientists, investors, and potential collaborators alike - to stay engaged with BEIT’s ongoing mission. Our team remains dedicated to solving the toughest challenges in quantum computing, pushing the frontier for more confident, transparent, and ultimately transformative applications in medicine.