Quantum Supermaps are Characterized by Locality

Summarize this article with:
AbstractWe provide a new characterisation of quantum supermaps in terms of an axiom that refers only to sequential and parallel composition. Consequently, we generalize quantum supermaps to arbitrary monoidal categories and operational probabilistic theories. We do so by providing a simple definition of $\textit{locally-applicable transformation}$ on a monoidal category. The definition can be rephrased in the language of category theory using the principle of naturality, and can be given an intuitive diagrammatic representation in terms of which all proofs are presented. In our main technical contribution, we use this diagrammatic representation to show that locally-applicable transformations on quantum channels are in one-to-one correspondence with deterministic quantum supermaps. This alternative characterization of quantum supermaps is proven to work for more general multiple-input supermaps such as the quantum switch and on arbitrary normal convex spaces of quantum channels such as those defined by satisfaction of signaling constraints.► BibTeX data@article{Wilson2026quantumsupermapsare, doi = {10.22331/q-2026-03-09-2013}, url = {https://doi.org/10.22331/q-2026-03-09-2013}, title = {Quantum {S}upermaps are {C}haracterized by {L}ocality}, author = {Wilson, Matt and Chiribella, Giulio and Kissinger, Aleks}, journal = {{Quantum}}, issn = {2521-327X}, publisher = {{Verein zur F{\"{o}}rderung des Open Access Publizierens in den Quantenwissenschaften}}, volume = {10}, pages = {2013}, month = mar, year = {2026} }► References [1] G. Chiribella, G. M. D'Ariano, and P. Perinotti, ``Transforming quantum operations: Quantum supermaps,'' EPL (Europhysics Letters) 83 no. 3, (7, 2008) 30004. https://doi.org/10.1209/0295-5075/83/30004 [2] G. Chiribella, G. M. D'Ariano, and P. Perinotti, ``Quantum circuit architecture,'' Physical Review Letters 101 no. 6, (8, 2008) 060401. https://doi.org/10.1103/PhysRevLett.101.060401 [3] G. Chiribella, G. M. D'Ariano, P. Perinotti, and B. Valiron, ``Quantum computations without definite causal structure,'' Physical Review A - Atomic, Molecular, and Optical Physics 88 no. 2, (8, 2013) 022318. https://doi.org/10.1103/PhysRevA.88.022318 [4] G. Chiribella, G. M. D'Ariano, and P. Perinotti, ``Theoretical framework for quantum networks,'' Physical Review A - Atomic, Molecular, and Optical Physics 80 no. 2, (4, 2009). https://doi.org/10.1103/PhysRevA.80.022339 [5] G. Chiribella, A. Toigo, and V. Umanità, ``Normal completely positive maps on the space of quantum operations,'' Open Systems and Information Dynamics 20 no. 1, (12, 2010). https://doi.org/10.1142/S1230161213500030 [6] A. Bisio and P. Perinotti, ``Theoretical framework for higher-order quantum theory,'' Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 475 no. 2225, (5, 2019) 20180706. https://doi.org/10.1098/rspa.2018.0706 [7] A. Kissinger and S. Uijlen, ``A categorical semantics for causal structure,'' Logical Methods in Computer Science 15 no. 3, (2019). https://doi.org/10.23638/LMCS-15(3:15)2019 [8] M. Wilson and G. Chiribella, ``A Mathematical Framework for Transformations of Physical Processes,'' arXiv:2204.04319 [quant-ph]. arXiv:2204.04319 [9] P. Perinotti, Causal Structures and the Classification of Higher Order Quantum Computations, pp. 103–127.
Springer International Publishing, Cham, 2017. https://doi.org/10.1007/978-3-319-68655-4_7 [10] H. Kristjánsson, G. Chiribella, S. Salek, D. Ebler, and M. Wilson, ``Resource theories of communication,'' New Journal of Physics 22 no. 7, (7, 2020) 073014. https://doi.org/10.1088/1367-2630/ab8ef7 [11] G. Gour and C. M. Scandolo, ``Dynamical Resources,'' arXiv:2101.01552v1 [quant-ph]. arXiv:2101.01552v1 [12] G. Gour and C. M. Scandolo, ``Entanglement of a bipartite channel,'' Physical Review A 103 (2021) 062422. https://doi.org/10.1103/PhysRevA.103.062422 [13] D. Ebler, S. Salek, and G. Chiribella, ``Enhanced Communication with the Assistance of Indefinite Causal Order,'' Physical Review Letters 120 no. 12, (3, 2018) 120502. https://doi.org/10.1103/PhysRevLett.120.120502 [14] L. M. Procopio, F. Delgado, M. Enríquez, N. Belabas, and J. A. Levenson, ``Communication Enhancement through Quantum Coherent Control of N Channels in an Indefinite Causal-Order Scenario,'' Entropy 21 no. 10, (10, 2019) 1012. https://doi.org/10.3390/e21101012 [15] L. M. Procopio, F. Delgado, M. Enríquez, N. Belabas, and J. A. Levenson, ``Sending classical information via three noisy channels in superposition of causal orders,'' Physical Review A 101 no. 1, (1, 2020) 012346. https://doi.org/10.1103/PhysRevA.101.012346 [16] G. Chiribella, M. Banik, S. S. Bhattacharya, T. Guha, M. Alimuddin, A. Roy, S. Saha, S. Agrawal, and G. Kar, ``Indefinite causal order enables perfect quantum communication with zero capacity channels,'' New Journal of Physics (2, 2021). https://doi.org/10.1088/1367-2630/abe7a0 [17] G. Chiribella, M. Wilson, and H. Chau, ``Quantum and Classical Data Transmission Through Completely Depolarising Channels in a Superposition of Cyclic Orders,'' Physical Review Letters 127 no. 19, (11, 2021) 190502. https://doi.org/10.1103/PhysRevLett.127.190502 [18] M. Wilson and G. Chiribella, ``A Diagrammatic Approach to Information Transmission in Generalised Switches,'' Electronic Proceedings in Theoretical Computer Science (EPTCS) 340 (2021) 333–348. https://doi.org/10.4204/EPTCS.340.17 [19] M. T. Quintino, Q. Dong, A. Shimbo, A. Soeda, and M. Murao, ``Probabilistic exact universal quantum circuits for transforming unitary operations,'' Phys. Rev. A 100 (Dec, 2019) 062339. https://doi.org/10.1103/PhysRevA.100.062339 [20] M. T. Quintino, Q. Dong, A. Shimbo, A. Soeda, and M. Murao, ``Reversing Unknown Quantum Transformations: Universal Quantum Circuit for Inverting General Unitary Operations,'' Physical Review Letters 123 no. 21, (11, 2019) 210502. https://doi.org/10.1103/PhysRevLett.123.210502 [21] Q. Dong, M. T. Quintino, A. Soeda, and M. Murao, ``Success-or-Draw: A Strategy Allowing Repeat-Until-Success in Quantum Computation,'' Physical Review Letters 126 no. 15, (4, 2021) 150504. https://doi.org/10.1103/PhysRevLett.126.150504 [22] P. A. Guérin, A. Feix, M. Araújo, and Ĉ. Brukner, ``Exponential Communication Complexity Advantage from Quantum Superposition of the Direction of Communication,'' Physical Review Letters 117 no. 10, (9, 2016) 100502. https://doi.org/10.1103/PhysRevLett.117.100502 [23] G. Chiribella, ``Perfect discrimination of no-signalling channels via quantum superposition of causal structures,'' Physical Review A - Atomic, Molecular, and Optical Physics 86 no. 4, (10, 2012) 040301. https://doi.org/10.1103/PhysRevA.86.040301 [24] M. Araújo, F. Costa, and Ĉ. Brukner, ``Computational advantage from quantum-controlled ordering of gates,'' Physical Review Letters 113 no. 25, (12, 2014) 250402. https://doi.org/10.1103/PhysRevLett.113.250402 [25] A. Feix, M. Araújo, and Č. Brukner, ``Quantum superposition of the order of parties as a communication resource,'' Physical Review A 92 no. 5, (11, 2015) 052326. https://doi.org/10.1103/PhysRevA.92.052326 [26] M. Román, ``Open Diagrams via Coend Calculus,'' Electronic Proceedings in Theoretical Computer Science 333 (2, 2021) 65–78. https://doi.org/10.4204/EPTCS.333.5 [27] M. Román, ``Comb Diagrams for Discrete-Time Feedback,'' tech. rep., 2020. arXiv:2003.06214v1 [quant-ph]. arXiv:2003.06214v1 [28] G. Boisseau, C. Nester, and M. Román, ``Cornering Optics,'' Electronic Proceedings in Theoretical Computer Science 380 (2023) 97–110. https://doi.org/10.4204/EPTCS.380.6 [29] J. Hedges, ``Coherence for lenses and open games,'' arXiv:1704.02230 [quant-ph]. arXiv:1704.02230 [30] M. Riley, ``Categories of Optics,'' arXiv:1809.00738 [math.CT]. arXiv:1809.00738 [31] N. Ghani, J. Hedges, V. Winschel, and P. Zahn, ``Compositional game theory,'' Proceedings of the 33rd Annual ACM/IEEE Symposium on Logic in Computer Science (LICS 2018) (2018) 472–481. https://doi.org/10.1145/3209108.3209165 [32] F. A. Pollock, C. Rodríguez-Rosario, T. Frauenheim, M. Paternostro, and K. Modi, ``Non-Markovian quantum processes: complete framework and efficient characterisation,'' Physical Review A 97 no. 1, (Jan, 2018) 012127. https://doi.org/10.1103/PhysRevA.97.012127 [33] J. Hefford and C. Comfort, ``Coend Optics for Quantum Combs,'' arXiv:2205.09027 [quant-ph]. arXiv:2205.09027 [34] G. Chiribella, G. M. D'Ariano, P. Perinotti, and B. Valiron, ``Quantum computations without definite causal structure,'' Physical Review A - Atomic, Molecular, and Optical Physics 88 no. 2, (12, 2009). https://doi.org/10.1103/PhysRevA.88.022318 [35] M. Araújo, P. A. Guérin, and Ä. Baumeler, ``Quantum computation with indefinite causal structures,'' Physical Review A 96 no. 5, (6, 2017). https://doi.org/10.1103/PhysRevA.96.052315 [36] M. J. Renner and Ĉ. Brukner, ``Reassessing the computational advantage of quantum-controlled ordering of gates,'' Physical Review Research 3 no. 4, (2, 2021). https://doi.org/10.1103/PhysRevResearch.3.043012 [37] D. Felce and V. Vedral, ``Quantum refrigeration with indefinite causal order,'' Phys. Rev. Lett. 125 (Aug, 2020) 070603. https://doi.org/10.1103/PhysRevLett.125.070603 [38] L. Hardy, ``Quantum mechanics, local realistic theories, and Lorentz-invariant realistic theories,'' Physical Review Letters 68 no. 20, (1992) 2981–2984. https://doi.org/10.1103/PhysRevLett.68.2981 [39] L. Hardy, ``Towards Quantum Gravity: A Framework for Probabilistic Theories with Non-Fixed Causal Structure,'' Journal of Physics A: Mathematical and Theoretical 40 no. 12, (8, 2006) 3081–3099. https://doi.org/10.1088/1751-8113/40/12/S12 [40] O. Oreshkov, F. Costa, and Ĉ. Brukner, ``Quantum correlations with no causal order,'' Nature Communications 3 (2012). https://doi.org/10.1038/ncomms2076 [41] Ä. Baumeler and S. Wolf, ``Perfect signaling among three parties violating predefined causal order,'' IEEE International Symposium on Information Theory - Proceedings (12, 2013) 526–530. https://doi.org/10.1109/ISIT.2014.6874888 [42] Ä. Baumeler and S. Wolf, ``The space of logically consistent classical processes without causal order,'' New Journal of Physics 18 no. 1, (7, 2015). https://doi.org/10.1088/1367-2630/18/1/013036 [43] E. Castro-Ruiz, F. Giacomini, and Ĉ. Brukner, ``Dynamics of Quantum Causal Structures,'' Physical Review X 8 no. 1, (3, 2018) 011047. https://doi.org/10.1103/PhysRevX.8.011047 [44] V. Baumann, M. Krumm, P. A. Guérin, and Ĉ. Brukner, ``Noncausal Page-Wootters circuits,'' Physical Review Research 4 no. 1, (5, 2021). https://doi.org/10.1103/PhysRevResearch.4.013180 [45] F. Costa, ``A no-go theorem for superpositions of causal orders,'' Quantum 6 (3, 2022) 663. https://doi.org/10.22331/q-2022-03-01-663 [46] R. Silva, Y. Guryanova, A. J. Short, P. Skrzypczyk, N. Brunner, and S. Popescu, ``Connecting processes with indefinite causal order and multi-time quantum states,'' New Journal of Physics 19 no. 10, (1, 2017). https://doi.org/10.1088/1367-2630/aa84fe [47] V. Vilasini and R. Renner, ``Embedding cyclic information-theoretic structures in acyclic space-times: No-go results for indefinite causality,'' Phys. Rev. A 110 (Aug, 2024) 022227. https://doi.org/10.1103/PhysRevA.110.022227 [48] N. Ormrod, A. Vanrietvelde, and J. Barrett, ``Causal structure in the presence of sectorial constraints, with application to the quantum switch,'' Quantum 7 (June, 2023) 1028. https://doi.org/10.22331/q-2023-06-01-1028 [49] D. Felce, N. T. Vidal, V. Vedral, and E. O. Dias, ``Indefinite causal orders from superpositions in time,'' Phys. Rev. A 105 (Jun, 2022) 062216. https://doi.org/10.1103/PhysRevA.105.062216 [50] O. Oreshkov and C. Giarmatzi, ``Causal and causally separable processes,'' New Journal of Physics 18 no. 9, (9, 2016) 093020. https://doi.org/10.1088/1367-2630/18/9/093020 [51] J. Wechs, H. Dourdent, A. A. Abbott, and C. Branciard, ``Quantum circuits with classical versus quantum control of causal order,'' PRX Quantum 2 no. 3, (1, 2021). https://doi.org/10.1103/PRXQuantum.2.030335 [52] T. Purves and A. J. Short, ``Quantum theory cannot violate a causal inequality,'' Phys. Rev. Lett. 127 (Sep, 2021) 110402. https://doi.org/10.1103/PhysRevLett.127.110402 [53] T. van der Lugt, J. Barrett, and G. Chiribella, ``Device-independent certification of indefinite causal order in the quantum switch,'' Nature Communications 14 no. 1, (2023) 5811. https://doi.org/10.1038/s41467-023-40162-8 [54] S. Gogioso and N. Pinzani, ``The topology and geometry of causality,'' 2022. https://arxiv.org/abs/2206.08911. arXiv:2206.08911 [55] M. D. Choi, ``Completely positive linear maps on complex matrices,'' Linear Algebra and Its Applications 10 no. 3, (1975) 285–290. https://doi.org/10.1016/0024-3795(75)90075-0 [56] B. Coecke and A. Kissinger, Picturing quantum processes: A first course in quantum theory and diagrammatic reasoning.
Cambridge University Press, 3, 2017. https://doi.org/10.1017/9781316219317 [57] C. Heunen and J. Vicary, ``Categories for Quantum Theory,'' Categories for Quantum Theory (11, 2019). https://doi.org/10.1093/OSO/9780198739623.001.0001 [58] S. Abramsky and B. Coecke, ``A categorical semantics of quantum protocols,'' Proceedings of the 19th Annual IEEE Symposium on Logic in Computer Science, 2004. (2004) 415–425. https://doi.org/10.1109/LICS.2004.1319636 [59] B. Coecke, ``Kindergarten quantum mechanics: Lecture notes,'' AIP Conference Proceedings 810 no. 1, (01, 2006) 81–98. https://doi.org/10.1063/1.2158713 [60] B. Coecke, ``Quantum picturalism,'' Contemporary Physics 51 no. 1, (1, 2010) 59–83. https://doi.org/10.1080/00107510903257624 [61] J. H. Selby, C. M. Scandolo, and B. Coecke, ``Reconstructing quantum theory from diagrammatic postulates,'' Quantum 5 (Apr., 2021) 445. https://doi.org/10.22331/q-2021-04-28-445 [62] S. M. Lane, Categories for the Working Mathematician, vol. 5 of Graduate Texts in Mathematics.
Springer New York, 1971. 10.1007/978-1-4612-9839-7. https://doi.org/10.1007/978-1-4757-4721-8 [63] A. Joyal and D. Verity, ``Traced monoidal categories,'' Math. Proc. Gamb. Phil. Soc 119 (2021) 447–451. https://doi.org/10.1017/S0305004100074338 [64] M. Hasegawa, ``Recursion from Cyclic Sharing: Traced Monoidal Categories and Models of Cyclic Lambda Calculi,'' Springer Verlag (1997) 196213. https://doi.org/10.1007/3-540-62688-3_37 [65] N. Pinzani, S. Gogioso, and B. Coecke, ``Categorical Semantics for Time Travel,'' Proceedings - Symposium on Logic in Computer Science 2019-June (1, 2019). https://doi.org/10.48550/arxiv.1902.00032 [66] S. Gogioso, ``A Process-Theoretic Church of the Larger Hilbert Space,'' arXiv:1905.13117 [quant-ph]. arXiv:1905.13117 [67] P. Arrighi, A. Durbec, and M. Wilson, ``Quantum networks theory,'' Quantum 8 (Oct., 2024) 1508. https://doi.org/10.22331/q-2024-10-23-1508 [68] R. Haag and D. Kastler, ``An Algebraic approach to quantum field theory,'' J.Math.Phys. 5 no. 7, (1964) 848–861. https://doi.org/10.1063/1.1704187 [69] J. E. Roberts, ``Localization in algebraic field theory,'' Communications in Mathematical Physics 85 no. 1, (Aug., 1982) 87–98. https://doi.org/10.1007/BF02029135 [70] S. Doplichera, ``The principle of locality: Effectiveness, fate, and challenges,'' Journal of Mathematical Physics 51 no. 1, (1, 2010) 015218. https://doi.org/10.1063/1.3276100 [71] R. Brunetti, K. Fredenhagen, and R. Verch, ``The generally covariant locality principle – A new paradigm for local quantum physics,'' Communications in Mathematical Physics 237 no. 1-2, (12, 2001) 31–68. https://doi.org/10.1007/s00220-003-0815-7 [72] F. Strocchi, ``Relativistic Quantum Mechanics and Field Theory,'' Foundations of Physics 34 no. 3, (1, 2004) 501–527. https://doi.org/10.1023/B:FOOP.0000019625.30165.35 [73] B. Coecke and R. Lal, ``Causal Categories: Relativistically Interacting Processes,'' Foundations of Physics 43 no. 4, (4, 2013) 458–501. https://doi.org/10.1007/s10701-012-9646-8 [74] T. Eggeling, D. Schlingemann, and R. F. Werner, ``Semicausal operations are semilocalizable,'' Europhysics Letters 57 no. 6, (2002) 782–788. https://doi.org/10.1209/epl/i2002-00579-4 [75] P. Perinotti, ``Causal influence in operational probabilistic theories,'' Quantum 5 (Aug, 2021) 515. https://doi.org/10.22331/q-2021-08-03-515 [76] R. Lorenz and J. Barrett, ``Causal and compositional structure of unitary transformations,'' Quantum 5 (July, 2021) 511. https://doi.org/10.22331/q-2021-07-28-511 [77] M. Wilson and A. Vanrietvelde, ``Composable constraints,'' arXiv:2112.06818 [quant-ph]. arXiv:2112.06818 [78] G. M. D’Ariano, G. Chiribella, and P. Perinotti, Quantum Theory from First Principles: An Informational Approach.
Cambridge University Press, 2017. https://doi.org/10.1017/9781107338340 [79] B. Coecke, T. Fritz, and R. W. Spekkens, ``A mathematical theory of resources,'' Inf. Comput. 250 (2016) 59–86. https://doi.org/10.1016/j.ic.2016.02.008 [80] S. Gogioso and F. Genovese, ``Infinite-dimensional categorical quantum mechanics,'' Electronic Proceedings in Theoretical Computer Science, EPTCS 236 (1, 2017) 51–69. https://doi.org/10.4204/EPTCS.236.4 [81] A. Vanrietvelde, H. Kristjánsson, and J. Barrett, ``Routed quantum circuits,'' Quantum 5 (7, 2021) 503. https://doi.org/10.22331/q-2021-07-13-503 [82] A. Vanrietvelde and G. Chiribella, ``Universal control of quantum processes using sector-preserving channels,'' Quantum Information and Computation 21 no. 15-16, (Dec, 2021) 1320–1352. https://doi.org/10.26421/QIC21.15-16-5 [83] J. Bavaresco, Ämin Baumeler, Y. Guryanova, and C. Budroni, ``Indefinite causal order in boxworld theories,'' arXiv:2411.00951 [quant-ph]. arXiv:2411.00951 [84] K. Sengupta, ``Achieving maximal causal indefiniteness in a maximally nonlocal theory,'' arXiv:2411.04201 [quant-ph]. arXiv:2411.04201 [85] P. E. Moliner, C. Heunen, and S. Tull, ``Space in Monoidal Categories,'' Electronic Proceedings in Theoretical Computer Science, EPTCS 266 (4, 2017) 399–410. https://doi.org/10.4204/EPTCS.266.25Cited byCould not fetch Crossref cited-by data during last attempt 2026-03-09 09:32:41: Could not fetch cited-by data for 10.22331/q-2026-03-09-2013 from Crossref. This is normal if the DOI was registered recently. Could not fetch ADS cited-by data during last attempt 2026-03-09 09:32:42: No response from ADS or unable to decode the received json data when getting the list of citing works.This Paper is published in Quantum under the Creative Commons Attribution 4.0 International (CC BY 4.0) license. Copyright remains with the original copyright holders such as the authors or their institutions. AbstractWe provide a new characterisation of quantum supermaps in terms of an axiom that refers only to sequential and parallel composition. Consequently, we generalize quantum supermaps to arbitrary monoidal categories and operational probabilistic theories. We do so by providing a simple definition of $\textit{locally-applicable transformation}$ on a monoidal category. The definition can be rephrased in the language of category theory using the principle of naturality, and can be given an intuitive diagrammatic representation in terms of which all proofs are presented. In our main technical contribution, we use this diagrammatic representation to show that locally-applicable transformations on quantum channels are in one-to-one correspondence with deterministic quantum supermaps. This alternative characterization of quantum supermaps is proven to work for more general multiple-input supermaps such as the quantum switch and on arbitrary normal convex spaces of quantum channels such as those defined by satisfaction of signaling constraints.► BibTeX data@article{Wilson2026quantumsupermapsare, doi = {10.22331/q-2026-03-09-2013}, url = {https://doi.org/10.22331/q-2026-03-09-2013}, title = {Quantum {S}upermaps are {C}haracterized by {L}ocality}, author = {Wilson, Matt and Chiribella, Giulio and Kissinger, Aleks}, journal = {{Quantum}}, issn = {2521-327X}, publisher = {{Verein zur F{\"{o}}rderung des Open Access Publizierens in den Quantenwissenschaften}}, volume = {10}, pages = {2013}, month = mar, year = {2026} }► References [1] G. Chiribella, G. M. D'Ariano, and P. Perinotti, ``Transforming quantum operations: Quantum supermaps,'' EPL (Europhysics Letters) 83 no. 3, (7, 2008) 30004. https://doi.org/10.1209/0295-5075/83/30004 [2] G. Chiribella, G. M. D'Ariano, and P. Perinotti, ``Quantum circuit architecture,'' Physical Review Letters 101 no. 6, (8, 2008) 060401. https://doi.org/10.1103/PhysRevLett.101.060401 [3] G. Chiribella, G. M. D'Ariano, P. Perinotti, and B. Valiron, ``Quantum computations without definite causal structure,'' Physical Review A - Atomic, Molecular, and Optical Physics 88 no. 2, (8, 2013) 022318. https://doi.org/10.1103/PhysRevA.88.022318 [4] G. Chiribella, G. M. D'Ariano, and P. Perinotti, ``Theoretical framework for quantum networks,'' Physical Review A - Atomic, Molecular, and Optical Physics 80 no. 2, (4, 2009). https://doi.org/10.1103/PhysRevA.80.022339 [5] G. Chiribella, A. Toigo, and V. Umanità, ``Normal completely positive maps on the space of quantum operations,'' Open Systems and Information Dynamics 20 no. 1, (12, 2010). https://doi.org/10.1142/S1230161213500030 [6] A. Bisio and P. Perinotti, ``Theoretical framework for higher-order quantum theory,'' Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 475 no. 2225, (5, 2019) 20180706. https://doi.org/10.1098/rspa.2018.0706 [7] A. Kissinger and S. Uijlen, ``A categorical semantics for causal structure,'' Logical Methods in Computer Science 15 no. 3, (2019). https://doi.org/10.23638/LMCS-15(3:15)2019 [8] M. Wilson and G. Chiribella, ``A Mathematical Framework for Transformations of Physical Processes,'' arXiv:2204.04319 [quant-ph]. arXiv:2204.04319 [9] P. Perinotti, Causal Structures and the Classification of Higher Order Quantum Computations, pp. 103–127.
Springer International Publishing, Cham, 2017. https://doi.org/10.1007/978-3-319-68655-4_7 [10] H. Kristjánsson, G. Chiribella, S. Salek, D. Ebler, and M. Wilson, ``Resource theories of communication,'' New Journal of Physics 22 no. 7, (7, 2020) 073014. https://doi.org/10.1088/1367-2630/ab8ef7 [11] G. Gour and C. M. Scandolo, ``Dynamical Resources,'' arXiv:2101.01552v1 [quant-ph]. arXiv:2101.01552v1 [12] G. Gour and C. M. Scandolo, ``Entanglement of a bipartite channel,'' Physical Review A 103 (2021) 062422. https://doi.org/10.1103/PhysRevA.103.062422 [13] D. Ebler, S. Salek, and G. Chiribella, ``Enhanced Communication with the Assistance of Indefinite Causal Order,'' Physical Review Letters 120 no. 12, (3, 2018) 120502. https://doi.org/10.1103/PhysRevLett.120.120502 [14] L. M. Procopio, F. Delgado, M. Enríquez, N. Belabas, and J. A. Levenson, ``Communication Enhancement through Quantum Coherent Control of N Channels in an Indefinite Causal-Order Scenario,'' Entropy 21 no. 10, (10, 2019) 1012. https://doi.org/10.3390/e21101012 [15] L. M. Procopio, F. Delgado, M. Enríquez, N. Belabas, and J. A. Levenson, ``Sending classical information via three noisy channels in superposition of causal orders,'' Physical Review A 101 no. 1, (1, 2020) 012346. https://doi.org/10.1103/PhysRevA.101.012346 [16] G. Chiribella, M. Banik, S. S. Bhattacharya, T. Guha, M. Alimuddin, A. Roy, S. Saha, S. Agrawal, and G. Kar, ``Indefinite causal order enables perfect quantum communication with zero capacity channels,'' New Journal of Physics (2, 2021). https://doi.org/10.1088/1367-2630/abe7a0 [17] G. Chiribella, M. Wilson, and H. Chau, ``Quantum and Classical Data Transmission Through Completely Depolarising Channels in a Superposition of Cyclic Orders,'' Physical Review Letters 127 no. 19, (11, 2021) 190502. https://doi.org/10.1103/PhysRevLett.127.190502 [18] M. Wilson and G. Chiribella, ``A Diagrammatic Approach to Information Transmission in Generalised Switches,'' Electronic Proceedings in Theoretical Computer Science (EPTCS) 340 (2021) 333–348. https://doi.org/10.4204/EPTCS.340.17 [19] M. T. Quintino, Q. Dong, A. Shimbo, A. Soeda, and M. Murao, ``Probabilistic exact universal quantum circuits for transforming unitary operations,'' Phys. Rev. A 100 (Dec, 2019) 062339. https://doi.org/10.1103/PhysRevA.100.062339 [20] M. T. Quintino, Q. Dong, A. Shimbo, A. Soeda, and M. Murao, ``Reversing Unknown Quantum Transformations: Universal Quantum Circuit for Inverting General Unitary Operations,'' Physical Review Letters 123 no. 21, (11, 2019) 210502. https://doi.org/10.1103/PhysRevLett.123.210502 [21] Q. Dong, M. T. Quintino, A. Soeda, and M. Murao, ``Success-or-Draw: A Strategy Allowing Repeat-Until-Success in Quantum Computation,'' Physical Review Letters 126 no. 15, (4, 2021) 150504. https://doi.org/10.1103/PhysRevLett.126.150504 [22] P. A. Guérin, A. Feix, M. Araújo, and Ĉ. Brukner, ``Exponential Communication Complexity Advantage from Quantum Superposition of the Direction of Communication,'' Physical Review Letters 117 no. 10, (9, 2016) 100502. https://doi.org/10.1103/PhysRevLett.117.100502 [23] G. Chiribella, ``Perfect discrimination of no-signalling channels via quantum superposition of causal structures,'' Physical Review A - Atomic, Molecular, and Optical Physics 86 no. 4, (10, 2012) 040301. https://doi.org/10.1103/PhysRevA.86.040301 [24] M. Araújo, F. Costa, and Ĉ. Brukner, ``Computational advantage from quantum-controlled ordering of gates,'' Physical Review Letters 113 no. 25, (12, 2014) 250402. https://doi.org/10.1103/PhysRevLett.113.250402 [25] A. Feix, M. Araújo, and Č. Brukner, ``Quantum superposition of the order of parties as a communication resource,'' Physical Review A 92 no. 5, (11, 2015) 052326. https://doi.org/10.1103/PhysRevA.92.052326 [26] M. Román, ``Open Diagrams via Coend Calculus,'' Electronic Proceedings in Theoretical Computer Science 333 (2, 2021) 65–78. https://doi.org/10.4204/EPTCS.333.5 [27] M. Román, ``Comb Diagrams for Discrete-Time Feedback,'' tech. rep., 2020. arXiv:2003.06214v1 [quant-ph]. arXiv:2003.06214v1 [28] G. Boisseau, C. Nester, and M. Román, ``Cornering Optics,'' Electronic Proceedings in Theoretical Computer Science 380 (2023) 97–110. https://doi.org/10.4204/EPTCS.380.6 [29] J. Hedges, ``Coherence for lenses and open games,'' arXiv:1704.02230 [quant-ph]. arXiv:1704.02230 [30] M. Riley, ``Categories of Optics,'' arXiv:1809.00738 [math.CT]. arXiv:1809.00738 [31] N. Ghani, J. Hedges, V. Winschel, and P. Zahn, ``Compositional game theory,'' Proceedings of the 33rd Annual ACM/IEEE Symposium on Logic in Computer Science (LICS 2018) (2018) 472–481. https://doi.org/10.1145/3209108.3209165 [32] F. A. Pollock, C. Rodríguez-Rosario, T. Frauenheim, M. Paternostro, and K. Modi, ``Non-Markovian quantum processes: complete framework and efficient characterisation,'' Physical Review A 97 no. 1, (Jan, 2018) 012127. https://doi.org/10.1103/PhysRevA.97.012127 [33] J. Hefford and C. Comfort, ``Coend Optics for Quantum Combs,'' arXiv:2205.09027 [quant-ph]. arXiv:2205.09027 [34] G. Chiribella, G. M. D'Ariano, P. Perinotti, and B. Valiron, ``Quantum computations without definite causal structure,'' Physical Review A - Atomic, Molecular, and Optical Physics 88 no. 2, (12, 2009). https://doi.org/10.1103/PhysRevA.88.022318 [35] M. Araújo, P. A. Guérin, and Ä. Baumeler, ``Quantum computation with indefinite causal structures,'' Physical Review A 96 no. 5, (6, 2017). https://doi.org/10.1103/PhysRevA.96.052315 [36] M. J. Renner and Ĉ. Brukner, ``Reassessing the computational advantage of quantum-controlled ordering of gates,'' Physical Review Research 3 no. 4, (2, 2021). https://doi.org/10.1103/PhysRevResearch.3.043012 [37] D. Felce and V. Vedral, ``Quantum refrigeration with indefinite causal order,'' Phys. Rev. Lett. 125 (Aug, 2020) 070603. https://doi.org/10.1103/PhysRevLett.125.070603 [38] L. Hardy, ``Quantum mechanics, local realistic theories, and Lorentz-invariant realistic theories,'' Physical Review Letters 68 no. 20, (1992) 2981–2984. https://doi.org/10.1103/PhysRevLett.68.2981 [39] L. Hardy, ``Towards Quantum Gravity: A Framework for Probabilistic Theories with Non-Fixed Causal Structure,'' Journal of Physics A: Mathematical and Theoretical 40 no. 12, (8, 2006) 3081–3099. https://doi.org/10.1088/1751-8113/40/12/S12 [40] O. Oreshkov, F. Costa, and Ĉ. Brukner, ``Quantum correlations with no causal order,'' Nature Communications 3 (2012). https://doi.org/10.1038/ncomms2076 [41] Ä. Baumeler and S. Wolf, ``Perfect signaling among three parties violating predefined causal order,'' IEEE International Symposium on Information Theory - Proceedings (12, 2013) 526–530. https://doi.org/10.1109/ISIT.2014.6874888 [42] Ä. Baumeler and S. Wolf, ``The space of logically consistent classical processes without causal order,'' New Journal of Physics 18 no. 1, (7, 2015). https://doi.org/10.1088/1367-2630/18/1/013036 [43] E. Castro-Ruiz, F. Giacomini, and Ĉ. Brukner, ``Dynamics of Quantum Causal Structures,'' Physical Review X 8 no. 1, (3, 2018) 011047. https://doi.org/10.1103/PhysRevX.8.011047 [44] V. Baumann, M. Krumm, P. A. Guérin, and Ĉ. Brukner, ``Noncausal Page-Wootters circuits,'' Physical Review Research 4 no. 1, (5, 2021). https://doi.org/10.1103/PhysRevResearch.4.013180 [45] F. Costa, ``A no-go theorem for superpositions of causal orders,'' Quantum 6 (3, 2022) 663. https://doi.org/10.22331/q-2022-03-01-663 [46] R. Silva, Y. Guryanova, A. J. Short, P. Skrzypczyk, N. Brunner, and S. Popescu, ``Connecting processes with indefinite causal order and multi-time quantum states,'' New Journal of Physics 19 no. 10, (1, 2017). https://doi.org/10.1088/1367-2630/aa84fe [47] V. Vilasini and R. Renner, ``Embedding cyclic information-theoretic structures in acyclic space-times: No-go results for indefinite causality,'' Phys. Rev. A 110 (Aug, 2024) 022227. https://doi.org/10.1103/PhysRevA.110.022227 [48] N. Ormrod, A. Vanrietvelde, and J. Barrett, ``Causal structure in the presence of sectorial constraints, with application to the quantum switch,'' Quantum 7 (June, 2023) 1028. https://doi.org/10.22331/q-2023-06-01-1028 [49] D. Felce, N. T. Vidal, V. Vedral, and E. O. Dias, ``Indefinite causal orders from superpositions in time,'' Phys. Rev. A 105 (Jun, 2022) 062216. https://doi.org/10.1103/PhysRevA.105.062216 [50] O. Oreshkov and C. Giarmatzi, ``Causal and causally separable processes,'' New Journal of Physics 18 no. 9, (9, 2016) 093020. https://doi.org/10.1088/1367-2630/18/9/093020 [51] J. Wechs, H. Dourdent, A. A. Abbott, and C. Branciard, ``Quantum circuits with classical versus quantum control of causal order,'' PRX Quantum 2 no. 3, (1, 2021). https://doi.org/10.1103/PRXQuantum.2.030335 [52] T. Purves and A. J. Short, ``Quantum theory cannot violate a causal inequality,'' Phys. Rev. Lett. 127 (Sep, 2021) 110402. https://doi.org/10.1103/PhysRevLett.127.110402 [53] T. van der Lugt, J. Barrett, and G. Chiribella, ``Device-independent certification of indefinite causal order in the quantum switch,'' Nature Communications 14 no. 1, (2023) 5811. https://doi.org/10.1038/s41467-023-40162-8 [54] S. Gogioso and N. Pinzani, ``The topology and geometry of causality,'' 2022. https://arxiv.org/abs/2206.08911. arXiv:2206.08911 [55] M. D. Choi, ``Completely positive linear maps on complex matrices,'' Linear Algebra and Its Applications 10 no. 3, (1975) 285–290. https://doi.org/10.1016/0024-3795(75)90075-0 [56] B. Coecke and A. Kissinger, Picturing quantum processes: A first course in quantum theory and diagrammatic reasoning.
Cambridge University Press, 3, 2017. https://doi.org/10.1017/9781316219317 [57] C. Heunen and J. Vicary, ``Categories for Quantum Theory,'' Categories for Quantum Theory (11, 2019). https://doi.org/10.1093/OSO/9780198739623.001.0001 [58] S. Abramsky and B. Coecke, ``A categorical semantics of quantum protocols,'' Proceedings of the 19th Annual IEEE Symposium on Logic in Computer Science, 2004. (2004) 415–425. https://doi.org/10.1109/LICS.2004.1319636 [59] B. Coecke, ``Kindergarten quantum mechanics: Lecture notes,'' AIP Conference Proceedings 810 no. 1, (01, 2006) 81–98. https://doi.org/10.1063/1.2158713 [60] B. Coecke, ``Quantum picturalism,'' Contemporary Physics 51 no. 1, (1, 2010) 59–83. https://doi.org/10.1080/00107510903257624 [61] J. H. Selby, C. M. Scandolo, and B. Coecke, ``Reconstructing quantum theory from diagrammatic postulates,'' Quantum 5 (Apr., 2021) 445. https://doi.org/10.22331/q-2021-04-28-445 [62] S. M. Lane, Categories for the Working Mathematician, vol. 5 of Graduate Texts in Mathematics.
Springer New York, 1971. 10.1007/978-1-4612-9839-7. https://doi.org/10.1007/978-1-4757-4721-8 [63] A. Joyal and D. Verity, ``Traced monoidal categories,'' Math. Proc. Gamb. Phil. Soc 119 (2021) 447–451. https://doi.org/10.1017/S0305004100074338 [64] M. Hasegawa, ``Recursion from Cyclic Sharing: Traced Monoidal Categories and Models of Cyclic Lambda Calculi,'' Springer Verlag (1997) 196213. https://doi.org/10.1007/3-540-62688-3_37 [65] N. Pinzani, S. Gogioso, and B. Coecke, ``Categorical Semantics for Time Travel,'' Proceedings - Symposium on Logic in Computer Science 2019-June (1, 2019). https://doi.org/10.48550/arxiv.1902.00032 [66] S. Gogioso, ``A Process-Theoretic Church of the Larger Hilbert Space,'' arXiv:1905.13117 [quant-ph]. arXiv:1905.13117 [67] P. Arrighi, A. Durbec, and M. Wilson, ``Quantum networks theory,'' Quantum 8 (Oct., 2024) 1508. https://doi.org/10.22331/q-2024-10-23-1508 [68] R. Haag and D. Kastler, ``An Algebraic approach to quantum field theory,'' J.Math.Phys. 5 no. 7, (1964) 848–861. https://doi.org/10.1063/1.1704187 [69] J. E. Roberts, ``Localization in algebraic field theory,'' Communications in Mathematical Physics 85 no. 1, (Aug., 1982) 87–98. https://doi.org/10.1007/BF02029135 [70] S. Doplichera, ``The principle of locality: Effectiveness, fate, and challenges,'' Journal of Mathematical Physics 51 no. 1, (1, 2010) 015218. https://doi.org/10.1063/1.3276100 [71] R. Brunetti, K. Fredenhagen, and R. Verch, ``The generally covariant locality principle – A new paradigm for local quantum physics,'' Communications in Mathematical Physics 237 no. 1-2, (12, 2001) 31–68. https://doi.org/10.1007/s00220-003-0815-7 [72] F. Strocchi, ``Relativistic Quantum Mechanics and Field Theory,'' Foundations of Physics 34 no. 3, (1, 2004) 501–527. https://doi.org/10.1023/B:FOOP.0000019625.30165.35 [73] B. Coecke and R. Lal, ``Causal Categories: Relativistically Interacting Processes,'' Foundations of Physics 43 no. 4, (4, 2013) 458–501. https://doi.org/10.1007/s10701-012-9646-8 [74] T. Eggeling, D. Schlingemann, and R. F. Werner, ``Semicausal operations are semilocalizable,'' Europhysics Letters 57 no. 6, (2002) 782–788. https://doi.org/10.1209/epl/i2002-00579-4 [75] P. Perinotti, ``Causal influence in operational probabilistic theories,'' Quantum 5 (Aug, 2021) 515. https://doi.org/10.22331/q-2021-08-03-515 [76] R. Lorenz and J. Barrett, ``Causal and compositional structure of unitary transformations,'' Quantum 5 (July, 2021) 511. https://doi.org/10.22331/q-2021-07-28-511 [77] M. Wilson and A. Vanrietvelde, ``Composable constraints,'' arXiv:2112.06818 [quant-ph]. arXiv:2112.06818 [78] G. M. D’Ariano, G. Chiribella, and P. Perinotti, Quantum Theory from First Principles: An Informational Approach.
Cambridge University Press, 2017. https://doi.org/10.1017/9781107338340 [79] B. Coecke, T. Fritz, and R. W. Spekkens, ``A mathematical theory of resources,'' Inf. Comput. 250 (2016) 59–86. https://doi.org/10.1016/j.ic.2016.02.008 [80] S. Gogioso and F. Genovese, ``Infinite-dimensional categorical quantum mechanics,'' Electronic Proceedings in Theoretical Computer Science, EPTCS 236 (1, 2017) 51–69. https://doi.org/10.4204/EPTCS.236.4 [81] A. Vanrietvelde, H. Kristjánsson, and J. Barrett, ``Routed quantum circuits,'' Quantum 5 (7, 2021) 503. https://doi.org/10.22331/q-2021-07-13-503 [82] A. Vanrietvelde and G. Chiribella, ``Universal control of quantum processes using sector-preserving channels,'' Quantum Information and Computation 21 no. 15-16, (Dec, 2021) 1320–1352. https://doi.org/10.26421/QIC21.15-16-5 [83] J. Bavaresco, Ämin Baumeler, Y. Guryanova, and C. Budroni, ``Indefinite causal order in boxworld theories,'' arXiv:2411.00951 [quant-ph]. arXiv:2411.00951 [84] K. Sengupta, ``Achieving maximal causal indefiniteness in a maximally nonlocal theory,'' arXiv:2411.04201 [quant-ph]. arXiv:2411.04201 [85] P. E. Moliner, C. Heunen, and S. Tull, ``Space in Monoidal Categories,'' Electronic Proceedings in Theoretical Computer Science, EPTCS 266 (4, 2017) 399–410. https://doi.org/10.4204/EPTCS.266.25Cited byCould not fetch Crossref cited-by data during last attempt 2026-03-09 09:32:41: Could not fetch cited-by data for 10.22331/q-2026-03-09-2013 from Crossref. This is normal if the DOI was registered recently. Could not fetch ADS cited-by data during last attempt 2026-03-09 09:32:42: No response from ADS or unable to decode the received json data when getting the list of citing works.This Paper is published in Quantum under the Creative Commons Attribution 4.0 International (CC BY 4.0) license. Copyright remains with the original copyright holders such as the authors or their institutions.
