Claudio Altafini
Professor
My research interests are broadly in the area of modeling and control of nonlinear dynamical systems.
Publication list
Recent preprints
Claudio Altafini, Multistability of Self-Attention Dynamics in Transformers (2025) 
https://arxiv.org/abs/2511.11553
Joel Wendin, Erik G. Larsson, Claudio Altafini, Computing frustration and near-monotonicity in deep neural networks (2025) https://arxiv.org/abs/2510.05286
Luca Claude Gino Lebon, Claudio Altafini, Geometric Control Theory Over Networks: Minimal Node Cardinality Disturbance Decoupling Problems (2025) https://arxiv.org/abs/2510.16689
Muhammad Ahsan Razaq, Claudio Altafini, Wisdom of Crowds Effects under Antagonistic Interactions and Correlated Opinions (2025) https://arxiv.org/abs/2510.19123
Journal papers
2025
Muhammad Ahsan Razaq, Claudio Altafini, 
Signed Friedkin-Johnsen Models: Opinion Dynamics With Stubbornness and Antagonism, IEEE Transactions on Automatic Control 70:5037-5051 (2025) 
https://doi.org/10.1109/TAC.2025.3532785
2024
Angela Fontan, Marco Ratta, Claudio Altafini, From populations to networks: Relating diversity indices and frustration in signed graphs, PNAS Nexus 3:pgae046 (2024) https://doi.org/10.1093/pnasnexus/pgae046
Carmela Bernardo, Claudio Altafini, Anton Proskurnikov, Francesco Vasca, Bounded confidence opinion dynamics: A survey, Automatica 159:111302 (2024) https://doi.org/10.1016/j.automatica.2023.111302
Lingfei Wang, Guanpu Chen, Carmela Bernardo, Yiguang Hong, Guodong Shi, Claudio Altafini, Social Power Games in Concatenated Opinion Dynamics, IEEE Transactions on Automatic Control 69:7614-7629 (2024) https://doi.org/10.1109/TAC.2024.3391870
Luca Claude Gino Lebon, Francesco Lo Iudice, Claudio Altafini, On controllability of temporal networks, European Journal of Control 80:101046 (2024) https://doi.org/10.1016/j.ejcon.2024.101046
Trisha Srivastava, Carmela Bernardo, Claudio Altafini, Francesco Vasca, Connectivity and Synchronization in Bounded Confidence Kuramoto Oscillators, IEEE Control Systems Letters 8:874-879 (2024) https://doi.org/10.1109/LCSYS.2024.3405379
2023
Alberto Zenere, Sandra Hellberg, Georgia Papapavlou Lingehed, Maria Svenvik, Johan Mellergård, Charlotte Dahle, Magnus Vrethem, Johanna Raffetseder, Mohsen Khademi, Tomas Olsson, Marie Blomberg, Maria Jenmalm, Claudio Altafini, Mika Gustafsson, Jan Ernerudh, Prominent epigenetic and transcriptomic changes in CD4(+) and CD8(+) T cells during and after pregnancy in women with multiple sclerosis and controls, Journal of Neuroinflammation 20:98 (2023) https://doi.org/10.1186/s12974-023-02781-2
Angela Fontan, Claudio Altafini, PSEUDOINVERSES OF SIGNED LAPLACIAN MATRICES, SIAM Journal on Matrix Analysis and Applications 44:622-647 (2023) https://doi.org/10.1137/22M1493392
Angela Fontan, Lingfei Wang, Yiguang Hong, Guodong Shi, Claudio Altafini, Multiagent Consensus Over Time-Invariant and Time-Varying Signed Digraphs via Eventual Positivity, IEEE Transactions on Automatic Control 68:5429-5444 (2023) https://doi.org/10.1109/tac.2022.3225472 https://arxiv.org/abs/2203.04215
Carmela Bernardo, Lingfei Wang, Mathias Fridahl, Claudio Altafini, Quantifying leadership in climate negotiations, PNAS Nexus 2:pgad365 (2023) https://doi.org/10.1093/pnasnexus/pgad365
Gustav Lindmark, Claudio Altafini, Investigating the effect of edge modifications on networked control systems: Stability analysis, Automatica 149:110801 (2023) https://doi.org/10.1016/j.automatica.2022.110801 https://arxiv.org/abs/2007.13713
Julia Åkesson, Sara Hojjati, Sandra Hellberg, Johanna Raffetseder, Mohsen Khademi, Robert Rynkowski, Ingrid Kockum, Claudio Altafini, Zelmina Lubovac-Pilav, Johan Mellergård, Maria Jenmalm, Fredrik Piehl, Tomas Olsson, Jan Ernerudh, Mika Gustafsson, Proteomics reveal biomarkers for diagnosis, disease activity and long-term disability outcomes in multiple sclerosis, Nature Communications 14:6903 (2023) https://doi.org/10.1038/s41467-023-42682-9
Lingfei Wang, Carmela Bernardo, Yiguang Hong, Francesco Vasca, Guodong Shi, Claudio Altafini, Consensus in Concatenated Opinion Dynamics With Stubborn Agents, IEEE Transactions on Automatic Control 68:4008-4023 (2023) https://doi.org/10.1109/TAC.2022.3200888
2022
Claudio Altafini, Giacomo Como, Julien M. Hendrickx, Alexander Olshevsky, Alireza Tahbaz-Salehi, Guest Editorial Special Issue on Dynamics and Behaviors in Social Networks, IEEE Transactions on Control of Network Systems 9:1053-1055 (2022) https://doi.org/10.1109/TCNS.2022.3198831
Alberto Zenere, Erik G Larsson, Claudio Altafini, Relating balance and conditional independence in graphical models, Physical review. E 106:044309 (2022) https://doi.org/10.1103/PhysRevE.106.044309
Alberto Zenere, Olof Rundquist, Mika Gustafsson, Claudio Altafini, Multi-omics protein-coding units as massively parallel Bayesian networks, iScience 25:104048 (2022) https://doi.org/10.1016/j.isci.2022.104048
Alberto Zenere, Olof Rundquist, Mika Gustafsson, Claudio Altafini, Using high-throughput multi-omics data to investigate structural balance in elementary gene regulatory network motifs, Bioinformatics 38:173-178 (2022) https://doi.org/10.1093/bioinformatics/btab577
Angela Fontan, Claudio Altafini, The role of frustration in collective decision-making dynamical processes on multiagent signed networks, IEEE Transactions on Automatic Control 67:5191-5206 (2022) https://doi.org/10.1109/TAC.2021.3123222
Carmela Bernardo, Claudio Altafini, Francesco Vasca, Finite-time convergence of opinion dynamics in homogeneous asymmetric bounded confidence models, European Journal of Control 68:100674 (2022) https://doi.org/10.1016/j.ejcon.2022.100674
Lingfei Wang, Yiguang Hong, Guodong Shi, Claudio Altafini, Signed Social Networks With Biased Assimilation, IEEE Transactions on Automatic Control 67:5134-5149 (2022) https://doi.org/10.1109/TAC.2021.3121221
Rasmus Magnusson, Olof Rundquist, Min Jung Kim, Sandra Hellberg, Chan Hyun Na, Mikael Benson, David Gomez-Cabrero, Ingrid Kockum, Jesper N. Tegner, Fredrik Piehl, Maja Jagodic, Johan Mellergård, Claudio Altafini, Jan Ernerudh, Maria Jenmalm, Colm Nestor, Min-Sik Kim, Mika Gustafsson, RNA-sequencing and mass-spectrometry proteomic time-series analysis of T-cell differentiation identified multiple splice variants models that predicted validated protein biomarkers in inflammatory diseases, Frontiers in Molecular Biosciences 9:916128 (2022) https://doi.org/10.3389/fmolb.2022.916128
2021
Angela Fontan, Claudio Altafini, A signed network perspective on the government formation process in parliamentary democracies, Scientific Reports 11:5134 (2021) https://doi.org/10.1038/s41598-021-84147-3
Carmela Bernardo, Lingfei Wang, Francesco Vasca, Yiguang Hong, Guodong Shi, Claudio Altafini, Achieving consensus in multilateral international negotiations, Science Advances 7:eabg8068 (2021) https://doi.org/10.1126/sciadv.abg8068
Gustav Lindmark, Claudio Altafini, Centrality Measures and the Role of Non-Normality for Network Control Energy Reduction, IEEE Control Systems Letters 5:1013-1018 (2021) https://doi.org/10.1109/LCSYS.2020.3008325 https://arxiv.org/abs/1806.05932
2020
Claudio Altafini, A system-theoretic framework for privacy preservation in continuous-time multiagent dynamics, Automatica 122:109253 (2020) https://doi.org/10.1016/j.automatica.2020.109253 https://arxiv.org/abs/1904.11246
Angela Fontan, Guodong Shi, Xiaoming Hu, Claudio Altafini, Interval Consensus for Multiagent Networks, IEEE Transactions on Automatic Control 65:1855-1869 (2020) https://doi.org/10.1109/TAC.2019.2924131
Gustav Lindmark, Claudio Altafini, On the impact of edge modifications for networked control systems, IFAC-PapersOnLine 53:10969-10974 (2020) https://doi.org/10.1016/j.ifacol.2020.12.2846
2019
Claudio Altafini, A dynamical approach to privacy preserving average consensus, Proc. of the 58th IEEE Conf. on Decision and Control, Nice, December (2019) https://arxiv.org/abs/1808.08085
Alejandra Gonzalez Bosca, Shadi Jafari, Alberto Zenere, Mattias Alenius, Claudio Altafini, Thermodynamic model of gene regulation for the Or59b olfactory receptor in Drosophila, PloS Computational Biology 15:e1006709 (2019) https://doi.org/10.1371/journal.pcbi.1006709
Guodong Shi, Claudio Altafini, John S. Baras, Dynamics over Signed Networks, SIAM Review 61:229-257 (2019) https://doi.org/10.1137/17M1134172
2018
Claudio Altafini, Francesca Ceragioli, Signed bounded confidence models for opinion dynamics, Automatica 93:114-125 (2018) https://doi.org/10.1016/j.automatica.2018.03.064
Angela Fontan, Claudio Altafini, Multiequilibria analysis for a class of collective decision-making networked systems, IEEE Transactions on Control of Network Systems:1931-1940 (2018) https://doi.org/10.1109/TCNS.2017.2774014
Gustav Lindmark, Claudio Altafini, Minimum energy control for complex networks, Scientific Reports 8:3188 (2018) https://doi.org/10.1038/s41598-018-21398-7 https://arxiv.org/abs/1612.03082
Precious Ugo Abara, Francesco Ticozzi, Claudio Altafini, Spectral Conditions for Stability and Stabilization of Positive Equilibria for a Class of Nonlinear Cooperative Systems, IEEE Transactions on Automatic Control 63:402-417 (2018) https://doi.org/10.1109/TAC.2017.2713241
2017
Claudio Altafini, Involutive flows and discretization errors for nonlinear driftless control systems, Systems & control letters (Print) 110:29-37 (2017) https://doi.org/10.1016/j.sysconle.2017.08.009
Giulia Giordano, Claudio Altafini, Qualitative and quantitative responses to press perturbations in ecological networks, Scientific Reports 7:11378 (2017) https://doi.org/10.1038/s41598-017-11221-0
Gustav Lindmark, Claudio Altafini, Controllability of complex networks with unilateral inputs, Scientific Reports 7:1824 (2017) https://doi.org/10.1038/s41598-017-01846-6
2016
Claudio Altafini, Minimal eventually positive realizations of externally positive systems, Automatica 68:140-147 (2016) https://doi.org/10.1016/j.automatica.2016.01.072
Claudio Altafini, The Geometric Phase of Stock Trading, PLOS ONE 11:e0161538 (2016) https://doi.org/10.1371/journal.pone.0161538 https://arxiv.org/abs/1603.05513
Nuria Ballber Torres, Claudio Altafini, Drug combinatorics and side effect estimation on the signed human drug-target network, BMC Systems Biology 10 (2016) https://doi.org/10.1186/s12918-016-0326-8
2015
Claudio Altafini, Gabriele Lini, Predictable Dynamics of Opinion Forming for Networks With Antagonistic Interactions, IEEE Transactions on Automatic Control 60:342-357 (2015) https://doi.org/10.1109/TAC.2014.2343371
Claudio Altafini, Giuseppe Facchetti, Metabolic Adaptation Processes That Converge to Optimal Biomass Flux Distributions, PloS Computational Biology 11:e1004434 (2015) https://doi.org/10.1371/journal.pcbi.1004434
Monica Mazzolini, Giuseppe Facchetti, Laura Andolfi, Remo Proietti Zaccaria, Salvatore Tuccio, Johannes Treu, Claudio Altafini, Enzo Di Fabrizio, Vincent Torre, The phototransduction machinery in the rod outer segment has a strong efficacy gradient, Proceedings of the National Academy of Sciences of the United States of America 112:E2715-E272 (2015) https://doi.org/10.1073/pnas.1423162112
2006
Claudio Altafini, Feedback control of spin systems, Quantum Inf Process (2007) 6: 9 (2006) https://doi.org/10.1007/s11128-006-0038-x https://arxiv.org/abs/quant-ph/0601016
Claudio Altafini, Timothy F. Havel, Reflection Symmetries for Multiqubit Density Operators, Journal of Mathematical Physics, 47, 032104 (2006) https://doi.org/10.1063/1.2181827 https://arxiv.org/abs/quant-ph/0405123
2005
Claudio Altafini, Commuting multiparty quantum observables and local compatibility, Physical Review A, 72:012112 (2005) https://doi.org/10.1103/PhysRevA.72.012112 https://arxiv.org/abs/quant-ph/0505223
2004
Claudio Altafini, Representing multiqubit unitary evolutions: spin coherences and infinitesimal coherences, Physical Review A, 70:032331 (2004) https://doi.org/10.1103/PhysRevA.70.032331 https://arxiv.org/abs/quant-ph/0404006
Claudio Altafini, Tensor of coherences parameterization of multiqubit density operators for entanglement characterization, Physical Review A, 69:012311 (2004) https://doi.org/10.1103/PhysRevA.69.012311 https://arxiv.org/abs/quant-ph/0308019
2003
C. Altafini, Controllability properties for finite dimensional quantum Markovian master equations, J. Math. Phys., 44(6):2357-2372 (2003) https://doi.org/10.1063/1.1571221 https://arxiv.org/abs/quant-ph/0211194
Claudio Altafini, Parameter differentiation and quantum state decomposition for time varying Schroedinger equations, Reports on Mathematical Physics, 52(3):381-400 (2003) https://doi.org/10.1016/S0034-4877(03)80037-X https://arxiv.org/abs/quant-ph/0201034
2002
C. Altafini, On the generation of sequential unitary gates from continuous time Schrodinger equations driven by external fields, Quantum Information Processing 1(3):207-224 (2002) https://arxiv.org/abs/quant-ph/0203005
Claudio Altafini, Controllability of quantum mechanical systems by root space decomposition of su(N), J. Math. Phys, 43(5):2051-2062 (2002) https://doi.org/10.1063/1.1467611 https://arxiv.org/abs/quant-ph/0110147
Conference papers
2024
Claudio Altafini, Razaq Muhammad Ahsan, Multidimensional signed Friedkin-Johnsen model, , IEEE, Milano (2024)
Lingfei Wang, Yu Xing, Claudio Altafini, Karl H. Johansson, Maximizing social power in multiple independent Friedkin-Johnsen models, 2024 EUROPEAN CONTROL CONFERENCE, ECC 2024, pp. 3422-3427, IEEE (2024) https://doi.org/10.23919/ECC64448.2024.10590759
Muhammad Ahsan Razaq, Claudio Altafini, Multidimensional signed Friedkin-Johnsen model, 2024 IEEE 63RD CONFERENCE ON DECISION AND CONTROL, CDC, IEEE Conference on Decision and Control, pp. 5304-5309, IEEE (2024) https://doi.org/10.1109/CDC56724.2024.10886756
2023
Muhammad Ahsan Razaq, Claudio Altafini, Propagation of Stubborn Opinions on Signed Graphs, 2023 62ND IEEE CONFERENCE ON DECISION AND CONTROL, CDC, IEEE Conference on Decision and Control, pp. 491-496, IEEE (2023) https://doi.org/10.1109/CDC49753.2023.10383479
Trisha Srivastava, Carmela Bernardo, Claudio Altafini, Francesco Vasca, Analyzing the effects of confidence thresholds on opinion clustering in homogeneous Hegselmann-Krause models, 2023 31ST MEDITERRANEAN CONFERENCE ON CONTROL AND AUTOMATION, MED, Mediterranean Conference on Control and Automation, pp. 587-592, IEEE (2023) https://doi.org/10.1109/MED59994.2023.10185838
2022
Lingfei Wang, Angela Fontan, Yiguang Hong, Guodong Shi, Claudio Altafini, Multi-agent consensus over signed graphs with switching topology, 2022 EUROPEAN CONTROL CONFERENCE (ECC), pp. 2216-2221, IEEE (2022) https://doi.org/10.23919/ECC55457.2022.9837983
Lingfei Wang, Guanpu Chen, Yiguang Hong, Guodong Shi, Claudio Altafini, A social power game for the concatenated Friedkin-Johnsen model, 2022 IEEE 61ST CONFERENCE ON DECISION AND CONTROL (CDC), IEEE Conference on Decision and Control, pp. 3513-3518, IEEE (2022) https://doi.org/10.1109/CDC51059.2022.9992374
2021
Angela Fontan, Claudio Altafini, On the properties of Laplacian pseudoinverses, 2021 IEEE 60th Conference on Decision and Control (CDC), IEEE Conference on Decision and Control (CDC), pp. 5538-5543, IEEE (2021) https://doi.org/10.1109/CDC45484.2021.9683525
L. Wang, C. Bernardo, Y. Hong, E. Vasca, G. Shi, Claudio Altafini, Achieving consensus in spite of stubbornness: time-varying concatenated Friedkin-Johnsen models, 2021 60TH IEEE CONFERENCE ON DECISION AND CONTROL (CDC), IEEE Conference on Decision and Control, pp. 4964-4969, IEEE (2021) https://doi.org/10.1109/CDC45484.2021.9683466
2020
Angela Fontan, Claudio Altafini, Describing government formation processes through collective multiagent dynamics on signed networks, , in (2020)
Lingfei Wang, Hong Yiguang, Shi Guodong, Claudio Altafini, A biased assimilation model on signed graphs, 2020 59th IEEE Conference on Decision and Control (CDC), IEEE Conference on Decision and Control (CDC), IEEE (2020) https://doi.org/10.1109/CDC42340.2020.9304000
2019
Claudio Altafini, A dynamical approach to privacy preserving average consensus, 2019 IEEE 58th Conference on Decision and Control (CDC), IEEE Conference on Decision and Control (CDC) (2019) https://doi.org/10.1109/CDC40024.2019.9029712
Claudio Altafini, Investigating stability of Laplacians on signed digraphs via eventual positivity, 2019 IEEE 58th Conference on Decision and Control (CDC), IEEE Conference on Decision and Control (CDC), IEEE (2019) https://doi.org/10.1109/CDC40024.2019.9030125
Gustav Lindmark, Claudio Altafini, Combining centrality measures for control energy reduction in network controllability problems, Proceedings of the 2019 European Control Conference (ECC), pp. 1518-1523, Institute of Electrical and Electronics Engineers (IEEE) (2019) https://doi.org/10.23919/ECC.2019.8795867
2018
Angela Fontan, Claudio Altafini, Achieving a decision in antagonistic multiagent networks: frustration determines commitment strength, 2018 IEEE CONFERENCE ON DECISION AND CONTROL (CDC), IEEE Conference on Decision and Control, pp. 109-114, IEEE (2018) https://doi.org/10.1109/CDC.2018.8619615
Angela Fontan, Claudio Altafini, Modeling wireless power transfer in a network of smart devices: a compartmental system approach, 2018 EUROPEAN CONTROL CONFERENCE (ECC), pp. 1468-1473, IEEE (2018) https://doi.org/10.23919/ECC.2018.8550547
2017
Angela Fontan, Claudio Altafini, Investigating mixed-sign equilibria for nonlinear collective decision-making systems, Proceedings from the 2017 IEEE 56th Annual Conference on Decision and Control (CDC), December 12-15, 2017, Melbourne, Australia, pp. 781-786 (2017) https://doi.org/10.1109/CDC.2017.8263755
Angela Fontan, Guodong Shi, Xiaoming Hu, Claudio Altafini, Interval Consensus: a novel class of constrained consensus problems for multiagent networks, 2017 IEEE 56TH ANNUAL CONFERENCE ON DECISION AND CONTROL (CDC), IEEE Conference on Decision and Control, IEEE (2017) https://doi.org/10.1109/CDC.2017.8264270
Giulia Giordano, Claudio Altafini, Interaction sign patterns in biological networks: from qualitative to quantitative criteria, 2017 IEEE 56TH ANNUAL CONFERENCE ON DECISION AND CONTROL (CDC), IEEE Conference on Decision and Control, IEEE (2017) https://doi.org/10.1109/CDC.2017.8264451
Guodong Shi, Claudio Altafini, John S. Baras, Algebraic-Graphical Approach for Signed Dynamical Networks, 2017 IEEE 56TH ANNUAL CONFERENCE ON DECISION AND CONTROL (CDC), IEEE Conference on Decision and Control, IEEE (2017) https://doi.org/10.1109/CDC.2017.8263943
Gustav Lindmark, Claudio Altafini, A driver node selection strategy for minimizing the control energy in complex networks, IFAC PAPERSONLINE, IFAC PAPERSONLINE, pp. 8309-8314, ELSEVIER SCIENCE BV (2017) https://doi.org/10.1016/j.ifacol.2017.08.1410
Gustav Lindmark, Claudio Altafini, Minimum energy control for networks of coupled harmonic oscillators, IFAC PAPERSONLINE, IFAC PAPERSONLINE, pp. 8321-8326, ELSEVIER SCIENCE BV (2017) https://doi.org/10.1016/j.ifacol.2017.08.1552
Gustav Lindmark, Claudio Altafini, Topological aspects of controlling large scale networks with unilateral inputs, IFAC PAPERSONLINE, IFAC PAPERSONLINE, pp. 8315-8320, ELSEVIER SCIENCE BV (2017) https://doi.org/10.1016/j.ifacol.2017.08.1549
2016
Claudio Altafini, Nonintegrable discrete-time driftless control systems: geometric phases beyond the area rule, 2016 IEEE 55th Conference on Decision and Control (CDC), IEEE Conference on Decision and Control, pp. 4692-4697, IEEE Press (2016) https://doi.org/10.1109/CDC.2016.7798984
Francesca Ceragioli, Gustav Lindmark, Clas Veibäck, Niklas Wahlström, Martin Lindfors, Claudio Altafini, A bounded confidence model that preserves the signs of the opinions, Proceedings of the 2016 European Control Conference, pp. 543-548, Institute of Electrical and Electronics Engineers (IEEE) (2016) https://doi.org/10.1109/ECC.2016.7810341
Gustav Lindmark, Claudio Altafini, Positive Controllability of Large-Scale Networks, Proceedings of the 2016 European Control Conference, pp. 819-824, Institute of Electrical and Electronics Engineers (IEEE) (2016) https://doi.org/10.1109/ECC.2016.7810390
Precious Ugo Abara, Francesco Ticozzi, Claudio Altafini, An infinitesimal characterization of nonlinear contracting interference functions, 2016 IEEE 55th Conference on Decision and Control (CDC), IEEE Conference on Decision and Control, pp. 5257-5262, IEEE Press (2016) https://doi.org/10.1109/CDC.2016.7799074
2015
Claudio Altafini, Representing externally positive systems through minimal eventually positive realizations, Proceedings of the IEEE 54th Annual Conference on Decision and Control (CDC),, IEEE Conference on Decision and Control. Proceedings, pp. 6385-6390, Institute of Electrical and Electronics Engineers (IEEE) (2015) https://doi.org/10.1109/CDC.2015.7403225
Ugo Abara Precious, Francesco Ticozzi, Claudio Altafini, Existence, uniqueness and stability properties of positive equilibria for a class of nonlinear cooperative systems, Proceedings of 54th IEEE Conference on Decision and Control (CDC), pp. 4406-4411, Institute of Electrical and Electronics Engineers (IEEE) (2015) https://doi.org/10.1109/CDC.2015.7402907
2014
Claudio Altafini, A continuous-time dynamical system that can sort agents through distributed protocols, 2014 IEEEMulti-conference on Systems and Control, pp. 2153-2158, Institute of Electrical and Electronics Engineers (IEEE), Antibes, France (2014) https://doi.org/10.1109/CCA.2014.6981621
Claudio Altafini, G. Lini, Achieving unanimous opinions in signed social networks, Control Conference (ECC), 2014 European, pp. 184-189, IEEE (2014) https://doi.org/10.1109/ECC.2014.6862161
Preprints
Claudio Altafini, Francesco Ticozzi, Almost Global Stochastic Feedback Stabilization of Conditional Quantum Dynamics (2005) https://arxiv.org/abs/quant-ph/0510222
Claudio Altafini, Characterizing 3-qubit UPB states: violations of LHV models, preparation via nonlocal unitaries and PPT entangled nonlocal orbits (2004) https://arxiv.org/abs/quant-ph/0405124