3 ms·

Hybrid VQE photonic qudits for accurate QC without error-correction techniques

3 points by westurner 2y ago

westurner 2y ago
From OT TA NewsArticle: "Photon qubits challenge AI, enabling more accurate quantum computing without error-correction techniques" https://phys.org/news/2024-11-photon-qubits-ai-enabling-accurate.html https://phys.org/news/2024-11-photon-qubits-ai-enabling-accu... : > VQE is a hybrid algorithm designed to use a Quantum Processing Unit (QPU) and a Classical Processing Unit (CPU) together to perform faster computations. > Global research teams, including IBM and Google, are investigating it in a variety of quantum systems, including superconducting and trapped-ion systems. However, qubit-based VQE is currently only implemented up to 2 qubits in photonic systems and 12 qubits in superconducting systems, and is challenged by error issues that make it difficult to scale when more qubits and complex computations are required. [...] > In this study, a qudit was implemented by the orbital angular momentum state of a single-photon, and dimensional expansion was possible by adjusting the phase of a photon through holographic images. This allowed for high-dimensional calculations without complex quantum gates, reducing errors. ScholarlyArticle: "Qudit-based variational quantum eigensolver using photonic orbital angular momentum states" (2024) https://www.science.org/doi/10.1126/sciadv.ado3472 https://www.science.org/doi/10.1126/sciadv.ado3472
- westurner 2y ago
  VQE: Variational Quantum Eigensolver: https://en.wikipedia.org/wiki/Variational_quantum_eigensolver https://en.wikipedia.org/wiki/Variational_quantum_eigensolve... : > Given a guess or ansatz, the quantum processor calculates the expectation value of the system with respect to an observable, often the Hamiltonian, and a classical optimizer is used to improve the guess. The algorithm is based on the variational method of quantum mechanics. [...] It is an example of a noisy intermediate-scale quantum (NISQ) algorithm
  - westurner 2y ago
    From https://news.ycombinator.com/item?id=42030319 https://news.ycombinator.com/item?id=42030319 : > "Learning quantum Hamiltonians at any temperature in polynomial time" (2024) https://arxiv.org/abs/2310.02243 https://arxiv.org/abs/2310.02243 re: the "relaxation technique" .. https://news.ycombinator.com/item?id=40396171 https://news.ycombinator.com/item?id=40396171 >> We fully resolve this problem, giving a polynomial time algorithm for learning H to precision ϵ from polynomially many copies of the Gibbs state at any constant β>0. >> Our main technical contribution is a new flat polynomial approximation to the exponential function, and a translation between multi-variate scalar polynomials and nested commutators. This enables us to formulate Hamiltonian learning as a polynomial system. We then show that solving a low-degree sum-of-squares relaxation of this polynomial system suffices to accurately learn the Hamiltonian. Relaxation (iterative method) https://en.wikipedia.org/wiki/Relaxation_(iterative_method) https://en.wikipedia.org/wiki/Relaxation_(iterative_method)
- westurner 2y ago
  > In this study, a qudit was implemented by the orbital angular momentum state of a single-photon, and dimensional expansion was possible by adjusting the phase of a photon through holographic images From https://news.ycombinator.com/item?id=40281756 https://news.ycombinator.com/item?id=40281756 .. from "Physicists use a 350-year-old theorem to reveal new properties of light waves" (2023) https://phys.org/news/2023-08-physicists-year-old-theorem-reveal-properties.amp https://phys.org/news/2023-08-physicists-year-old-theorem-re... : > This means that hard-to-measure optical properties such as amplitudes, phases and correlations—perhaps even these of quantum wave systems—can be deduced from something a lot easier to measure: light intensity. > [..] Qian's team interpreted the intensity of a light as the equivalent of a physical object's mass, then mapped those measurements onto a coordinate system that could be interpreted using Huygens' mechanical theorem. "Essentially, we found a way to translate an optical system so we could visualize it as a mechanical system, then describe it using well-established physical equations," explained Qian. > Once the team visualized a light wave as part of a mechanical system, new connections between the wave's properties immediately became apparent—including the fact that entanglement and polarization stood in a clear relationship with one another. Shouldn't that make holography and photonic phase sensors and light field cameras possible with existing photographic intensity sensors? "Bridging coherence optics and classical mechanics: A generic light polarization-entanglement complementary relation" (2023) https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.5.033110 https://journals.aps.org/prresearch/abstract/10.1103/PhysRev...
  - westurner 2y ago
    Huygens-Fresnel principle: https://en.wikipedia.org/wiki/Huygens%E2%80%93Fresnel_principle https://en.wikipedia.org/wiki/Huygens%E2%80%93Fresnel_princi... Parallel axis theorem: https://en.wikipedia.org/wiki/Parallel_axis_theorem https://en.wikipedia.org/wiki/Parallel_axis_theorem

3 points by westurner 2y ago

From OT TA NewsArticle: "Photon qubits challenge AI, enabling more accurate quantum computing without error-correction techniques" https://phys.org/news/2024-11-photon-qubits-ai-enabling-accurate.html https://phys.org/news/2024-11-photon-qubits-ai-enabling-accu... : > VQE is a hybrid algorithm designed to use a Quantum Processing Unit (QPU) and a Classical Processing Unit (CPU) together to perform faster computations. > Global research teams, including IBM and Google, are investigating it in a variety of quantum systems, including superconducting and trapped-ion systems. However, qubit-based VQE is currently only implemented up to 2 qubits in photonic systems and 12 qubits in superconducting systems, and is challenged by error issues that make it difficult to scale when more qubits and complex computations are required. [...] > In this study, a qudit was implemented by the orbital angular momentum state of a single-photon, and dimensional expansion was possible by adjusting the phase of a photon through holographic images. This allowed for high-dimensional calculations without complex quantum gates, reducing errors. ScholarlyArticle: "Qudit-based variational quantum eigensolver using photonic orbital angular momentum states" (2024) https://www.science.org/doi/10.1126/sciadv.ado3472 https://www.science.org/doi/10.1126/sciadv.ado3472

westurner 2y ago
VQE: Variational Quantum Eigensolver: https://en.wikipedia.org/wiki/Variational_quantum_eigensolver https://en.wikipedia.org/wiki/Variational_quantum_eigensolve... : > Given a guess or ansatz, the quantum processor calculates the expectation value of the system with respect to an observable, often the Hamiltonian, and a classical optimizer is used to improve the guess. The algorithm is based on the variational method of quantum mechanics. [...] It is an example of a noisy intermediate-scale quantum (NISQ) algorithm
- westurner 2y ago
  From https://news.ycombinator.com/item?id=42030319 https://news.ycombinator.com/item?id=42030319 : > "Learning quantum Hamiltonians at any temperature in polynomial time" (2024) https://arxiv.org/abs/2310.02243 https://arxiv.org/abs/2310.02243 re: the "relaxation technique" .. https://news.ycombinator.com/item?id=40396171 https://news.ycombinator.com/item?id=40396171 >> We fully resolve this problem, giving a polynomial time algorithm for learning H to precision ϵ from polynomially many copies of the Gibbs state at any constant β>0. >> Our main technical contribution is a new flat polynomial approximation to the exponential function, and a translation between multi-variate scalar polynomials and nested commutators. This enables us to formulate Hamiltonian learning as a polynomial system. We then show that solving a low-degree sum-of-squares relaxation of this polynomial system suffices to accurately learn the Hamiltonian. Relaxation (iterative method) https://en.wikipedia.org/wiki/Relaxation_(iterative_method) https://en.wikipedia.org/wiki/Relaxation_(iterative_method)
westurner 2y ago
> In this study, a qudit was implemented by the orbital angular momentum state of a single-photon, and dimensional expansion was possible by adjusting the phase of a photon through holographic images From https://news.ycombinator.com/item?id=40281756 https://news.ycombinator.com/item?id=40281756 .. from "Physicists use a 350-year-old theorem to reveal new properties of light waves" (2023) https://phys.org/news/2023-08-physicists-year-old-theorem-reveal-properties.amp https://phys.org/news/2023-08-physicists-year-old-theorem-re... : > This means that hard-to-measure optical properties such as amplitudes, phases and correlations—perhaps even these of quantum wave systems—can be deduced from something a lot easier to measure: light intensity. > [..] Qian's team interpreted the intensity of a light as the equivalent of a physical object's mass, then mapped those measurements onto a coordinate system that could be interpreted using Huygens' mechanical theorem. "Essentially, we found a way to translate an optical system so we could visualize it as a mechanical system, then describe it using well-established physical equations," explained Qian. > Once the team visualized a light wave as part of a mechanical system, new connections between the wave's properties immediately became apparent—including the fact that entanglement and polarization stood in a clear relationship with one another. Shouldn't that make holography and photonic phase sensors and light field cameras possible with existing photographic intensity sensors? "Bridging coherence optics and classical mechanics: A generic light polarization-entanglement complementary relation" (2023) https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.5.033110 https://journals.aps.org/prresearch/abstract/10.1103/PhysRev...
- westurner 2y ago
  Huygens-Fresnel principle: https://en.wikipedia.org/wiki/Huygens%E2%80%93Fresnel_principle https://en.wikipedia.org/wiki/Huygens%E2%80%93Fresnel_princi... Parallel axis theorem: https://en.wikipedia.org/wiki/Parallel_axis_theorem https://en.wikipedia.org/wiki/Parallel_axis_theorem