[ { "id": "authors:gnrr3-rdt94", "collection": "authors", "collection_id": "gnrr3-rdt94", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220113-182244311", "type": "monograph", "title": "Spin chains, defects, and quantum wires for the quantum-double edge", "author": [ { "family_name": "Albert", "given_name": "Victor V.", "orcid": "0000-0002-0335-9508", "clpid": "Albert-Victor-V" }, { "family_name": "Aasen", "given_name": "David", "orcid": "0000-0002-6552-488X", "clpid": "Aasen-David" }, { "family_name": "Xu", "given_name": "Wenqing", "clpid": "Xu-Wenqing-William" }, { "family_name": "Ji", "given_name": "Wenjie", "clpid": "Ji-Wenjie" }, { "family_name": "Alicea", "given_name": "Jason", "orcid": "0000-0001-9979-3423", "clpid": "Alicea-J" }, { "family_name": "Preskill", "given_name": "John", "orcid": "0000-0002-2421-4762", "clpid": "Preskill-J" } ], "abstract": "Non-Abelian defects that bind Majorana or parafermion zero modes are prominent in several topological quantum computation schemes. Underpinning their established understanding is the quantum Ising spin chain, which can be recast as a fermionic model or viewed as a standalone effective theory for the surface-code edge -- both of which harbor non-Abelian defects. We generalize these notions by deriving an effective Ising-like spin chain describing the edge of quantum-double topological order. Relating Majorana and parafermion modes to anyonic strings, we introduce quantum-double generalizations of non-Abelian defects. We develop a way to embed finite-group valued qunits into those valued in continuous groups. Using this embedding, we provide a continuum description of the spin chain and recast its non-interacting part as a quantum wire via addition of a Wess-Zumino-Novikov-Witten term and non-Abelian bosonization.", "doi": "10.48550/arXiv.2111.12096", "publisher": "arXiv", "publication_date": "2021-11-23" }, { "id": "authors:z351a-qyb72", "collection": "authors", "collection_id": "z351a-qyb72", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220113-182219174", "type": "monograph", "title": "Provably accurate simulation of gauge theories and bosonic systems", "author": [ { "family_name": "Tong", "given_name": "Yu", "clpid": "Tong-Yu" }, { "family_name": "Albert", "given_name": "Victor V.", "orcid": "0000-0002-0335-9508", "clpid": "Albert-Victor-V" }, { "family_name": "McClean", "given_name": "Jarrod R.", "orcid": "0000-0002-2809-0509", "clpid": "McClean-Jarrod-R" }, { "family_name": "Preskill", "given_name": "John", "orcid": "0000-0002-2421-4762", "clpid": "Preskill-J" }, { "family_name": "Su", "given_name": "Yuan", "orcid": "0000-0003-1144-3563", "clpid": "Su-Yuan" } ], "abstract": "Quantum many-body systems involving bosonic modes or gauge fields have infinite-dimensional local Hilbert spaces which must be truncated to perform simulations of real-time dynamics on classical or quantum computers. To analyze the truncation error, we develop methods for bounding the rate of growth of local quantum numbers such as the occupation number of a mode at a lattice site, or the electric field at a lattice link. Our approach applies to various models of bosons interacting with spins or fermions, and also to both abelian and non-abelian gauge theories. We show that if states in these models are truncated by imposing an upper limit \u039b on each local quantum number, and if the initial state has low local quantum numbers, then an error at most \u03f5 can be achieved by choosing \u039b to scale polylogarithmically with \u03f5\u207b\u00b9, an exponential improvement over previous bounds based on energy conservation. For the Hubbard-Holstein model, we numerically compute a bound on \u039b that achieves accuracy \u03f5, obtaining significantly improved estimates in various parameter regimes. We also establish a criterion for truncating the Hamiltonian with a provable guarantee on the accuracy of time evolution. Building on that result, we formulate quantum algorithms for dynamical simulation of lattice gauge theories and of models with bosonic modes; the gate complexity depends almost linearly on spacetime volume in the former case, and almost quadratically on time in the latter case. We establish a lower bound showing that there are systems involving bosons for which this quadratic scaling with time cannot be improved. By applying our result on the truncation error in time evolution, we also prove that spectrally isolated energy eigenstates can be approximated with accuracy \u03f5 by truncating local quantum numbers at \u039b = polylog(\u03f5\u207b\u00b9).", "doi": "10.48550/arXiv.2110.06942", "publisher": "arXiv", "publication_date": "2021-10-13" }, { "id": "authors:2vwsn-wzz50", "collection": "authors", "collection_id": "2vwsn-wzz50", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220104-233146603", "type": "monograph", "title": "Provably efficient machine learning for quantum many-body problems", "author": [ { "family_name": "Huang", "given_name": "Hsin-Yuan", "orcid": "0000-0001-5317-2613", "clpid": "Huang-Hsin-Yuan-Robert" }, { "family_name": "Kueng", "given_name": "Richard", "orcid": "0000-0002-8291-648X", "clpid": "Kueng-Richard-J" }, { "family_name": "Torlai", "given_name": "Giacomo", "orcid": "0000-0001-8478-4436", "clpid": "Torlai-Giacomo" }, { "family_name": "Albert", "given_name": "Victor V.", "orcid": "0000-0002-0335-9508", "clpid": "Albert-Victor-V" }, { "family_name": "Preskill", "given_name": "John", "orcid": "0000-0002-2421-4762", "clpid": "Preskill-J" } ], "abstract": "Classical machine learning (ML) provides a potentially powerful approach to solving challenging quantum many-body problems in physics and chemistry. However, the advantages of ML over more traditional methods have not been firmly established. In this work, we prove that classical ML algorithms can efficiently predict ground state properties of gapped Hamiltonians in finite spatial dimensions, after learning from data obtained by measuring other Hamiltonians in the same quantum phase of matter. In contrast, under widely accepted complexity theory assumptions, classical algorithms that do not learn from data cannot achieve the same guarantee. We also prove that classical ML algorithms can efficiently classify a wide range of quantum phases of matter. Our arguments are based on the concept of a classical shadow, a succinct classical description of a many-body quantum state that can be constructed in feasible quantum experiments and be used to predict many properties of the state. Extensive numerical experiments corroborate our theoretical results in a variety of scenarios, including Rydberg atom systems, 2D random Heisenberg models, symmetry-protected topological phases, and topologically ordered phases.", "doi": "10.48550/arXiv.2106.12627", "publisher": "arXiv", "publication_date": "2021-06-23" }, { "id": "authors:d3hjb-yrc95", "collection": "authors", "collection_id": "d3hjb-yrc95", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220104-233143218", "type": "monograph", "title": "Quantum computing 40 years later", "author": [ { "family_name": "Preskill", "given_name": "John", "orcid": "0000-0002-2421-4762", "clpid": "Preskill-J" } ], "abstract": "Forty years ago, Richard Feynman proposed harnessing quantum physics to build a more powerful kind of computer. Realizing Feynman's vision is one of the grand challenges facing 21st century science and technology. In this article, we'll recall Feynman's contribution that launched the quest for a quantum computer, and assess where the field stands 40 years later.", "doi": "10.48550/arXiv.2106.10522", "publisher": "arXiv", "publication_date": "2021-06-19" }, { "id": "authors:439gs-vdh32", "collection": "authors", "collection_id": "439gs-vdh32", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210512-104044668", "type": "monograph", "title": "Opportunities for DOE National Laboratory-led QuantISED Experiments", "author": [ { "family_name": "Barry", "given_name": "Peter", "clpid": "Barry-Peter-S" }, { "family_name": "Berggren", "given_name": "Karl", "orcid": "0000-0001-7453-9031", "clpid": "Berggren-Karl-K" }, { "family_name": "Balantekin", "given_name": "A. Baha", "clpid": "Balantekin-A-Baha" }, { "family_name": "Bollinger", "given_name": "John", "orcid": "0000-0001-9117-7896", "clpid": "Bollinger-John-J" }, { "family_name": "Bunker", "given_name": "Ray", "orcid": "0000-0003-2174-7632", "clpid": "Bunker-Raymond" }, { "family_name": "Charaev", "given_name": "Ilya", "orcid": "0000-0002-4036-0778", "clpid": "Charaev-Ilya" }, { "family_name": "Chiles", "given_name": "Jeff", "orcid": "0000-0001-7508-3048", "clpid": "Chiles-Jeff" }, { "family_name": "Chou", "given_name": "Aaron", "clpid": "Chou-Aaron-S" }, { "family_name": "Demarteau", "given_name": "Marcel", "orcid": "0000-0001-9409-4308", "clpid": "Demarteau-Marcel" }, { "family_name": "Formaggio", "given_name": "Joe", "orcid": "0000-0002-3757-9883", "clpid": "Formaggio-J-A" }, { "family_name": "Graham", "given_name": "Peter", "orcid": "0000-0002-1600-1601", "clpid": "Graham-Peter" }, { "family_name": "Habib", "given_name": "Salman", "clpid": "Habib-Salman" }, { "family_name": "Hume", "given_name": "David", "clpid": "Hume-David" }, { "family_name": "Irwin", "given_name": "Kent", "orcid": "0000-0002-2998-9743", "clpid": "Irwin-Kent-D" }, { "family_name": "Lukin", "given_name": "Mikhail", "orcid": "0000-0002-8658-1007", "clpid": "Lukin-Mikhail-D" }, { "family_name": "Lykken", "given_name": "Joseph", "orcid": "0000-0002-0090-9439", "clpid": "Lykken-Joseph-D" }, { "family_name": "Maruyama", "given_name": "Reina", "orcid": "0000-0003-2794-512X", "clpid": "Maruyama-Reina" }, { "family_name": "Mueller", "given_name": "Holger", "orcid": "0000-0003-0636-5951", "clpid": "Mueller-Holger" }, { "family_name": "Nam", "given_name": "SaeWoo", "clpid": "Nam-SaeWoo" }, { "family_name": "Nomerotski", "given_name": "Andrei", "orcid": "0000-0001-5444-5345", "clpid": "Nomerotski-Andrei" }, { "family_name": "Orrell", "given_name": "John", "clpid": "Orell-John" }, { "family_name": "Plunkett", "given_name": "Robert", "orcid": "0000-0002-6770-1771", "clpid": "Plunkett-Robert" }, { "family_name": "Pooser", "given_name": "Raphael", "orcid": "0000-0002-2922-453X", "clpid": "Pooser-Raphael" }, { "family_name": "Preskill", "given_name": "John P.", "orcid": "0000-0002-2421-4762", "clpid": "Preskill-J" }, { "family_name": "Rajendran", "given_name": "Surjeet", "orcid": "0000-0001-9915-3573", "clpid": "Rajendran-Surjeet" }, { "family_name": "Sushkov", "given_name": "Alex", "orcid": "0000-0001-8895-6338", "clpid": "Sushkov-Alexander-O" }, { "family_name": "Walsworth", "given_name": "Ronald", "orcid": "0000-0003-0311-4751", "clpid": "Walsworth-Ronald-L" } ], "abstract": "A subset of QuantISED Sensor PIs met virtually on May 26, 2020 to discuss a response to a charge by the DOE Office of High Energy Physics. In this document, we summarize the QuantISED sensor community discussion, including a consideration of HEP science enabled by quantum sensors, describing the distinction between Quantum 1.0 and Quantum 2.0, and discussing synergies/complementarity with the new DOE NQI centers and with research supported by other SC offices. \n\nQuantum 2.0 advances in sensor technology offer many opportunities and new approaches for HEP experiments. The DOE HEP QuantISED program could support a portfolio of small experiments based on these advances. QuantISED experiments could use sensor technologies that exemplify Quantum 2.0 breakthroughs. They would strive to achieve new HEP science results, while possibly spinning off other domain science applications or serving as pathfinders for future HEP science targets. QuantISED experiments should be led by a DOE laboratory, to take advantage of laboratory technical resources, infrastructure, and expertise in the safe and efficient construction, operation, and review of experiments. \n\nThe QuantISED PIs emphasized that the quest for HEP science results under the QuantISED program is distinct from the ongoing DOE HEP programs on the energy, intensity, and cosmic frontiers. There is robust evidence for the existence of particles and phenomena beyond the Standard Model, including dark matter, dark energy, quantum gravity, and new physics responsible for neutrino masses, cosmic inflation, and the cosmic preference for matter over antimatter. Where is this physics and how do we find it? The QuantISED program can exploit new capabilities provided by quantum technology to probe these kinds of science questions in new ways and over a broader range of science parameters than can be achieved with conventional techniques.", "doi": "10.48550/arXiv.2102.10996", "publisher": "arXiv", "publication_date": "2021-02-05" }, { "id": "authors:gcbp1-s4w76", "collection": "authors", "collection_id": "gcbp1-s4w76", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210512-095238258", "type": "monograph", "title": "Models of quantum complexity growth", "author": [ { "family_name": "Brand\u00e3o", "given_name": "Fernando G. S. L.", "orcid": "0000-0003-3866-9378", "clpid": "Brand\u00e3o-F-G-S-L" }, { "family_name": "Chemissany", "given_name": "Wissam", "orcid": "0000-0002-9113-4463", "clpid": "Chemissany-Wissam" }, { "family_name": "Hunter-Jones", "given_name": "Nicholas", "orcid": "0000-0001-8578-1958", "clpid": "Hunter-Jones-Nicholas" }, { "family_name": "Kueng", "given_name": "Richard", "clpid": "Kueng-Richard-J" }, { "family_name": "Preskill", "given_name": "John", "orcid": "0000-0002-2421-4762", "clpid": "Preskill-J" } ], "abstract": "The concept of quantum complexity has far-reaching implications spanning theoretical computer science, quantum many-body physics, and high energy physics. The quantum complexity of a unitary transformation or quantum state is defined as the size of the shortest quantum computation that executes the unitary or prepares the state. It is reasonable to expect that the complexity of a quantum state governed by a chaotic many-body Hamiltonian grows linearly with time for a time that is exponential in the system size; however, because it is hard to rule out a short-cut that improves the efficiency of a computation, it is notoriously difficult to derive lower bounds on quantum complexity for particular unitaries or states without making additional assumptions. To go further, one may study more generic models of complexity growth. We provide a rigorous connection between complexity growth and unitary k-designs, ensembles which capture the randomness of the unitary group. This connection allows us to leverage existing results about design growth to draw conclusions about the growth of complexity. We prove that local random quantum circuits generate unitary transformations whose complexity grows linearly for a long time, mirroring the behavior one expects in chaotic quantum systems and verifying conjectures by Brown and Susskind. Moreover, our results apply under a strong definition of quantum complexity based on optimal distinguishing measurements.", "doi": "10.48550/arXiv.1912.04297", "publisher": "arXiv", "publication_date": "2019-12-09" }, { "id": "authors:386jx-np407", "collection": "authors", "collection_id": "386jx-np407", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160426-213243084", "type": "monograph", "title": "Quantum Shannon Theory", "author": [ { "family_name": "Preskill", "given_name": "John", "orcid": "0000-0002-2421-4762", "clpid": "Preskill-J" } ], "abstract": "This is the 10th and final chapter of my book on Quantum Information, based\non the course I have been teaching at Caltech since 1997. An early version of\nthis chapter (originally Chapter 5) has been available on the course website\nsince 1998, but this version is substantially revised and expanded. The level\nof detail is uneven, as I've aimed to provide a gentle introduction, but I've\nalso tried to avoid statements that are incorrect or obscure. Generally\nspeaking, I chose to include topics that are both useful to know and relatively\neasy to explain; I had to leave out a lot of good stuff, but on the other hand\nthe chapter is already quite long. This is a working draft of Chapter 10, which\nI will continue to update. See the URL on the title page for further updates\nand drafts of other chapters, and please send me an email if you notice errors.\nEventually, the complete book will be published by Cambridge University Press.", "doi": "10.48550/arXiv.1604.07450", "publisher": "arXiv", "publication_date": "2016-04-25" }, { "id": "authors:pt01q-wdy02", "collection": "authors", "collection_id": "pt01q-wdy02", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140529-115454760", "type": "monograph", "title": "Quantum Algorithms for Fermionic Quantum Field Theories", "author": [ { "family_name": "Jordan", "given_name": "Stephen P.", "clpid": "Jordan-S-P" }, { "family_name": "Lee", "given_name": "Keith S. M.", "clpid": "Lee-S-M" }, { "family_name": "Preskill", "given_name": "John", "orcid": "0000-0002-2421-4762", "clpid": "Preskill-J" } ], "abstract": "Extending previous work on scalar field theories, we develop a quantum\nalgorithm to compute relativistic scattering amplitudes in fermionic field\ntheories, exemplified by the massive Gross-Neveu model, a theory in two\nspacetime dimensions with quartic interactions. The algorithm introduces new\ntechniques to meet the additional challenges posed by the characteristics of\nfermionic fields, and its run time is polynomial in the desired precision and\nthe energy. Thus, it constitutes further progress towards an efficient quantum\nalgorithm for simulating the Standard Model of particle physics.", "doi": "10.48550/arXiv.1404.7115", "publisher": "arXiv", "publication_date": "2014-04-28" }, { "id": "authors:y45bm-sz592", "collection": "authors", "collection_id": "y45bm-sz592", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120925-151257143", "type": "monograph", "title": "Do Black Holes Destroy Information?", "author": [ { "family_name": "Preskill", "given_name": "John", "orcid": "0000-0002-2421-4762", "clpid": "Preskill-J" } ], "abstract": "I review the information loss paradox that was first formulated by Hawking, and discuss possible ways of resolving it. All proposed solutions have serious drawbacks. I conclude that the information loss paradox may well presage a\nrevolution in fundamental physics.", "doi": "10.48550/arXiv.9209058", "publication_date": "1992-09-16" } ]