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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 11 of 11 for “"Quantum complexity"”.
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A study on complexity
This thesis explores quantum complexity for various quantum systems. Quantum complexity is a well defined quantity in quantum information theory that measures the difficulty of constructing a quantum state from a given reference state and so far, various methods within high energy physics …
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Quantum query complexity revisited
… thesis, we look at the polynomial method for quantum query complexity and relate it to the BQPA = PA question for a random oracle A. We will also look at some open problems and improve some bounds relating classical and quantum complexity.
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Complexity of Basis-Restricted Local Hamiltonians
A major goal of quantum complexity theory is to understand which computational problems can be solved with access to certain quantum resources. The subfield of Hamiltonian complexity specifically considers computational problems that ask about properties of local Hamiltonians, which are of critical …
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Quantum proof systems and entanglement theory
Quantum complexity theory is important from the point of view of not only theory of computation but also quantum information theory. In particular, quantum multi-prover interactive proof systems are defined based on complexity theory notions, while their characterization can be formulated using …
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Combinatorial algorithms for perturbation theory and application on quantum computing
<p>Quantum computing is an emerging area between computer science and physics. Numerous problems in quantum computing involve quantum many-body interactions. This dissertation concerns the problem of simulating arbitrary quantum many-body interactions using realistic two-body interactions. To …
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Beyond qubits: Quantum optimization and lattice gauge theories in a qudit framework
Quantum computing holds the promise of tackling problems that are intractable for classical machines, yet the path from current noisy intermediate-scale quantum (NISQ) devices to fault-tolerant processors demands both better algorithms and a deeper understanding of how to exploit the full structure …
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Probing Local Many-Body Dynamics with Random Quantum Circuits
Random quantum circuits are an attractive model for the behavior of complex many-body physics, due to their analytic tractability as well as ability to reproduce the behavior of chaotic quantum systems. Recent progress in elucidating their structure has led to an improved understanding of quantum …
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Control, gates, and error suppression with Hamiltonians in quantum computation
… perform simulation, and implement logic gates in quantum computation within the context of using Hamiltonian controls. We also study the complexity class QMA-complete. We first investigate a method (introduced by Jordan, Farhi, and Shor) for suppressing environmentally induced errors in …
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Computational complexity of certain quantum theories in 1+1 dimensions
… observables like mass and temperature, and also complexity at the same time. For example, similar to saying that one object is heavier than the other, we can discuss which system is more complex. According to this point of view, a more complex system can be interpreted as the one which can be …
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Algorithmic Quantum-State Generation for Simulating Quantum Field Theories on a Quantum Computer
Simulating a quantum field theory (QFT) on a quantum computer comprises three steps: generating an initial state, simulating time evolution and measuring observables, with the initial-state generation being the most expensive step for the entire simulation. In this thesis, we introduce a general …
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The complexity of joint computation
… and begin an original line of inquiry into the complexity of joint computation. In more detail, we make contributions in the following areas: Improved direct product theorems for randomized query complexity: The "direct product problem" seeks to understand how the difficulty of computing a …