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arXiv · 2512.02284

Quantum-Classical Separation in Bounded-Resource Tasks Arising from Measurement Contextuality

Shashwat Kumar·Eliott Rosenberg·Alejandro Grajales Dau·Rodrigo Cortinas·Dmitri Maslov·Richard Oliver·Adam Zalcman·Matthew Neeley·Alice Pagano·Aaron Szasz·Ilya Drozdov·Zlatko Minev·Craig Gidney·Noureldin Yosri·Stijn J. de Graaf·Aniket Maiti·Dmitry Abanin·Rajeev Acharya·Laleh Aghababaie Beni·Georg Aigeldinger·Ross Alcaraz·Sayra Alcaraz·Trond I. Andersen·Markus Ansmann·Frank Arute·Kunal Arya·Walt Askew·Nikita Astrakhantsev·Juan Atalaya·Ryan Babbush·Brian Ballard·Joseph C. Bardin·Hector Bates·Andreas Bengtsson·Martin Bigdeli·Alexander Bilmes·Simon Bilodeau·Felix Borjans·Alexandre Bourassa·Jenna Bovaird·Dylan Bowers·Leon Brill·Peter Brooks·Michael Broughton·David A. Browne·Brett Buchea·Bob B. Buckley·Tim Burger·Brian Burkett·Nicholas Bushnell·Jamal Busnaina·Anthony Cabrera·Juan Campero·Hung-Shen Chang·Silas Chen·Zijun Chen·Ben Chiaro·Liang-Ying Chih·Jahan Claes·Agnetta Y. Cleland·Bryan Cochrane·Matt Cockrell·Josh Cogan·Roberto Collins·Paul Conner·Harold Cook·William Courtney·Alexander L. Crook·Ben Curtin·Sayan Das·Laura De Lorenzo·Sean Demura·Agustin Di Paolo·Paul Donohoe·Andrew Dunsworth·Valerie Ehimhen·Alec Eickbusch·Aviv Moshe Elbag·Lior Ella·Mahmoud Elzouka·David Enriquez·Catherine Erickson·Vinicius S. Ferreira·Marcos Flores·Leslie Flores Burgos·Ebrahim Forati·Jeremiah Ford·Austin G. Fowler·Brooks Foxen·Masaya Fukami·Alan Wing Lun Fung·Lenny Fuste·Suhas Ganjam·Gonzalo Garcia·Christopher Garrick·Robert Gasca·Helge Gehring·Élie Genois·William Giang·Dar Gilboa
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Abstract

The prevailing view is that quantum phenomena can be harnessed to tackle certain problems beyond the reach of classical approaches. Quantifying this capability as a quantum-classical separation and demonstrating it on current quantum processors has remained elusive. Using a superconducting qubit processor, we show that quantum contextuality enables certain tasks to be performed with success probabilities beyond classical limits. With a few qubits, we illustrate quantum contextuality with the magic square game, as well as quantify it through a Kochen--Specker--Bell inequality violation. To examine many-body contextuality, we implement the N-player GHZ game and separately solve a 2D hidden linear function problem, exceeding classical success rate in both. Our work proposes novel ways to benchmark quantum processors using contextuality-based algorithms.

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Shashwat Kumar, Eliott Rosenberg, Alejandro Grajales Dau, Rodrigo Cortinas, Dmitri Maslov, Richard Oliver, Adam Zalcman, Matthew Neeley, Alice Pagano, Aaron Szasz, Ilya Drozdov, Zlatko Minev, Craig Gidney, Noureldin Yosri, Stijn J. de Graaf, Aniket Maiti, Dmitry Abanin, Rajeev Acharya, Laleh Aghababaie Beni, Georg Aigeldinger, Ross Alcaraz, Sayra Alcaraz, Trond I. Andersen, Markus Ansmann, Frank Arute, Kunal Arya, Walt Askew, Nikita Astrakhantsev, Juan Atalaya, Ryan Babbush, Brian Ballard, Joseph C. Bardin, Hector Bates, Andreas Bengtsson, Martin Bigdeli, Alexander Bilmes, Simon Bilodeau, Felix Borjans, Alexandre Bourassa, Jenna Bovaird, Dylan Bowers, Leon Brill, Peter Brooks, Michael Broughton, David A. Browne, Brett Buchea, Bob B. Buckley, Tim Burger, Brian Burkett, Nicholas Bushnell, Jamal Busnaina, Anthony Cabrera, Juan Campero, Hung-Shen Chang, Silas Chen, Zijun Chen, Ben Chiaro, Liang-Ying Chih, Jahan Claes, Agnetta Y. Cleland, Bryan Cochrane, Matt Cockrell, Josh Cogan, Roberto Collins, Paul Conner, Harold Cook, William Courtney, Alexander L. Crook, Ben Curtin, Sayan Das, Laura De Lorenzo, Sean Demura, Agustin Di Paolo, Paul Donohoe, Andrew Dunsworth, Valerie Ehimhen, Alec Eickbusch, Aviv Moshe Elbag, Lior Ella, Mahmoud Elzouka, David Enriquez, Catherine Erickson, Vinicius S. Ferreira, Marcos Flores, Leslie Flores Burgos, Ebrahim Forati, Jeremiah Ford, Austin G. Fowler, Brooks Foxen, Masaya Fukami, Alan Wing Lun Fung, Lenny Fuste, Suhas Ganjam, Gonzalo Garcia, Christopher Garrick, Robert Gasca, Helge Gehring, Élie Genois, William Giang, Dar Gilboa. 2025-12-01. Quantum-Classical Separation in Bounded-Resource Tasks Arising from Measurement Contextuality. https://arxiv.org/abs/2512.02284

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