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Future of QI Future of QI The Benasque Quantum Information Workshops 2011 – 2019 compiled by Adán Cabello and Géza Giedke July 2019 The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 1 / 25 The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 2 / 25 2011 +5 more... 2013 2013: Achievements in the last few years Q Optics & Implementations Quantum Info ground state nanomech syst Universal qc w/ q walk detection-loophole-free Unifying q correlations photonic exp QC w/ little entanglement superconducting qubits security device-indep QKD q sim.: high-energy physics in opt lattices Foundations QP q sim.: beating class comp PBR Theorem Many-Body Physics activation of q nonlocality complexity of Hamiltonians Q thermo: Landauer’s criticality in open systems principle & 2nd Laws time-dependent variational principle The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 7 / 25 2013: Open Problems I Quantum Info Foundations QP NPT bound entanglement bound ent violate Bell Ineq? Q violation Ingleton ineq beyond Bell Ineq m-partite entanglement: principles for Q correlations characterization & applic relativity & QM in low-energy Q discord ?? physics LOCC: characterization QI + relativity rôle of entanglement in QC B.H. info paradox / firewall device-indep: general are Leggett-Garg Ineq useful? framework security; decidability in QIT certification of spacelike sep non-locality in many-body phys non-additivity of EOF/class capacity: examples life after loophole-free Bell Exp QC more powerful than CC? Tsirelson’s Problem PPT2 ) ent breaking Q chaos & entanglement The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 8 / 25 2013: Open Problems II Many-Body Physics Q Optics & Implementations efficient sim of Q Dynamics what is D-Wave doing? classific phases higher D implementations of QI stuff approx TN Q networks thermalization cheap QKD non-equilib inequalities satellite-based Q Comm (quantum) certification of Q Sim simulation TN HEP long-distance ent-based QC ? TN , AdS/CFT exp test of PBR-like theorems relation fluctuat $ entang. many-body state prep low-energy effective theories def ent of bosons/fermions self-protect. Q Mem. D < 4? limitations of Q simulations robustness topolog memories Boson Sampling (limitations) The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 9 / 25 2013 – Concluding Session The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 10 / 25 2013 – Concluding Session The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 10 / 25 The Top 10 of Open QIS Challenges 2013 1 Q computation more powerful than classical? (62) 2 New q algorithms (45) 3 Certification of q simulation (42) 4 Black Holes, general relativity & q information (black hole information paradox) (41) 6 Long-distance q communication (networks, satellites) (36) 6 Principles for q correlations (36) 7 Loophole-free Bell test (30) 8 better QECC (29) 9 robust topological QC & QMemory (26) 10 timescales for thermalization (25) 10 high-energy physics and QI (tensor networks) (25) The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 11 / 25 2015 2015 Open Problems The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 13 / 25 2015 Open Problems The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 13 / 25 2015 Open Problems The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 13 / 25 2017 2017 Open Problems I QI physical multipartite Foundations entanglement role of causality coherence theory and new reconstructions based on entanglement interpretations QI and gravity (ECC) q thermodynamics Black Holes / holography network vs Bell nonlocality (supreme) quantum machine certification of randomness learning and quantumness in temporal new killer applications for QC correlations resources for delegated QC QT–exotic space-times q approach to nonlinear connection channels falsifying sensitve collapse q speedup before QECC? models NPT bound entanglement? why probabilities? The Benasquenon-additivity Quantum Information issues Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 16 / 25 2017 Open Problems I Implementations useful q metrology Many-body understanding Fermi-Hubbard more applications tensor model networks q thermo machines to use many-body localization certifying q supremacy without applications of TN to: RNG, (or with) universality QFT, q learning, c learning q certification quantum PCP conjecture device-independent QKD efficient algorithms for gapless q nanophotonics for QIP systems is FTQC really possible? open q systems w non-Markovian effects is adiabatic QC really possible? make a surface code The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 17 / 25 Bets over the years NPT bound entanglement? 2011 Ruskai: No general composable security proof for DI-QKD 2011 Winter: yes; Acín: 2 yrs Peres’ Conjecture? 2011 Perez-García: False Vertesi and Brunner 2014 optimal states for 1-mode Gaussian channels? 2011 García-Patrón: vacuum( ) loophole-free Bell test 2011 Kleinmann: > 2y 2013 Cabello: 2y, Weinfurter( ) 2015: Hensen et al; Giustina et al; Shalm et al D-wave QC? 2011 Cirac: No (2y) q repeater better than direct transmission 2011 Brask Bohr: 3y q sim better than c sim Lewenstein: 2y; Cirac: > 1y the variational method? 2013 Cirac: PEPS (10y) business interest in QC will increase 2015 Latorre: yes (2y) The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 18 / 25 Voted predictions a universal quantum computer within our lifetimes? in 2013: YES: 50; NO: 16 in 2015: YES: 60; NO: 11; ABS: 5. predictions 2017 (for 2019): • quantum computers with X qubits and 103 gates: (A) > 100 qubits (3; 4%) (B) 50 − 100 (37; 58%) (C) < 50 (24; 46%) • device-independent QKD: (A) < 1km (3; 6%) (B) 1 − 10km (35; 71%) (C) > 10k (11, 23%) • reliable phase diagram Hubbard model: (A) Yes (9; 29%) (B) NO (22; 71%) • q metrology: commercial device using (A) only entanglement (24; 61%) (B) entanglement and (Q?)EC (2; 5%) (C) none (13, 33%) The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 19 / 25 The 2019 Quantum Information Workshop 2019 recent advances – major open problems – bets/predictions The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 20 / 25 The 2019 Quantum Information Workshop The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 21 / 25 The 2019 Quantum Information Workshop The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 21 / 25 The 2019 Quantum Information Workshop The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 21 / 25 2019: Recent Advances Quantum Information Many-body Proof of DI QKD Fermi Hubbard (Corboz et al.) (Arnon-Friedman et al., ’16) Constructions from free Q separation constant-depth fermions circuit (Bravyi, Gosset, Koenig ’18) Frustrated q spin models not Classical verification of QC tractable by Q Monte Carlo (Mahadev, 2018) Implementations Simulation of Boson sampling Many-body localization in 2d Quantum foundations (Bloch) Wigner’s friend (Frauchinger & Quasicrystals in optical lattices Renner) (Bloch?) Bell correlations (Slofstra 2017...) Tweezer technology (Lukin) Emergence object. reality (Müller) Scaling up to 50 qubits (ions, Redundancy in Q postulates atoms, and sc qubits) (Masanes, Galley, Müller 2018) Satellite (Micius) The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 22 / 25 2019: Open problems I Quantum information Many-body verification & benchmarks of TNs and QFT QC Proof of MBL phase quantum machine learning Out-of-equilibrium dynamics NPT bound entanglement? Foundations of QFT Can QC break post-q crypto? TN investigations of strong Resources to break correlations position-based crypto Experiment theory corrections Q supremacy proof Classification of topological Problems useful for QML phases in 3D Multipartite entanglement Applications of TNs outside QEC: Higher-threshold error QMB physics correcting codes with less Finite temperature results overhead The Benasque Quantum Information Workshops2011 – 2019compiledFuture of by QI Adán Cabello and Géza Giedke July 2019 23 / 25 2019: Open problems II Foundations Unified Framework for temporal and spatial Q correlations Implementations/Experiment Principles (and bounds) for Q correlations Room-temp SC Why are Q correlations for bell QSim of Q gravity scenarios not closed? detection of Q Gravity effects Indefinite causal order Proof of Q supremacy Business & Societal Commercial devices for large investments (financial, metrology and sensing chemical,...) DI QKD ethics? q bubble? and consequences? open access
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