pith. sign in

arxiv: 2605.17542 · v1 · pith:F6KZY3BXnew · submitted 2026-05-17 · 🧮 math.NA · cs.NA· physics.comp-ph

Quantum circuits for the advection-diffusion equation with boundary conditions based on LCHS

Pith reviewed 2026-05-19 22:39 UTC · model grok-4.3

classification 🧮 math.NA cs.NAphysics.comp-ph
keywords quantum algorithmsadvection-diffusion equationboundary conditionsHamiltonian simulationfinite volume methoderror analysisgate complexityPDE solving
0
0 comments X

The pith

A quantum circuit framework using LCHS solves advection-diffusion equations with boundary conditions and provides error bounds.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

This paper develops an explicit way to build quantum circuits that simulate the advection-diffusion equation, handling different boundary conditions through finite volume discretization and the linear combination of Hamiltonian simulations. It includes careful analysis of the approximation errors when combining unitaries and shows that the number of gates needed grows in a way that could be better than classical methods for problems in many dimensions. A reader might care because many real-world processes like fluid flow or heat transfer with boundaries are modeled by this equation, and quantum computers might eventually handle larger versions of them efficiently.

Core claim

The paper claims that the LCHS-based approach, after applying finite volume methods with appropriate flux schemes, yields quantum circuits for the advection-diffusion equation under Robin boundary conditions (which include Dirichlet and Neumann) and periodic boundaries. Detailed error bounds are derived for the linear combination of unitaries, and gate complexity is analyzed to demonstrate potential quantum advantages in high-dimensional cases. Numerical tests on a fault-tolerant emulator confirm the approach works for various problem types.

What carries the argument

The Linear Combination of Hamiltonian Simulations (LCHS), which expresses the time evolution operator as a weighted sum of unitary operators that can be implemented on quantum hardware.

Load-bearing premise

The finite-volume discretization combined with LCHS produces a linear combination of unitaries whose error bounds hold independently of the boundary condition details and translate to accurate solutions on quantum devices.

What would settle it

Implementing the circuits on a fault-tolerant quantum computer for a high-dimensional test case and verifying that the observed solution error aligns with or stays within the theoretical LCU error bound.

Figures

Figures reproduced from arXiv: 2605.17542 by and Kun Wang, Leyu Chen, Liang Xu, Tiegang Liu.

Figure 1
Figure 1. Figure 1: Quantum circuit for the homo￾geneous term. oq1 Ocoef1,r O † coef1,l . . . oqmo aq1 Ocoef2,r O † coef2,l . . . aqm sq1 SEL-Oprep SEL-Uk,j (T) . . . sqn [PITH_FULL_IMAGE:figures/full_fig_p004_1.png] view at source ↗
Figure 4
Figure 4. Figure 4: Quantum circuit for Wj (γτ,λ). Next, we introduce two projection operators that characterize the corner entries of the coefficient matrix under the Robin BCs: σ00 :=  1 0 0 0 , σ11 :=  0 0 0 1 . (4.6) It is straightforward to verify that their n-fold tensor products are diagonal projectors σ ⊗n 00 =      1 0 . . . 0      N×N , σ ⊗n 11 =      0 . . . 0 1      N×N , (4.7) which corres… view at source ↗
Figure 5
Figure 5. Figure 5: Quantum circuit for S (1) n (γτ). sq1 X X sq2 X X . . . sqn−1 X X sqn X P(−γτ ) X [PITH_FULL_IMAGE:figures/full_fig_p012_5.png] view at source ↗
Figure 7
Figure 7. Figure 7: Quantum circuit for Vn(γτ,λ). 4.2 Robin boundary conditions Building on the operator representations in Section 4.1 and the explicit matrix forms of the ODE system under the Robin BCs (Eqs. (3.16) and (3.19)), we rewrite the coefficient matrix A in a unified operator form as A=2αI− [PITH_FULL_IMAGE:figures/full_fig_p012_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: Numerical results for Experiment 1 (homogeneous 1D diffusion equation with Dirichlet BCs) [PITH_FULL_IMAGE:figures/full_fig_p026_8.png] view at source ↗
Figure 9
Figure 9. Figure 9: Numerical results for Experiment 2 (homogeneous 1D diffusion equation with Neumann BCs) [PITH_FULL_IMAGE:figures/full_fig_p027_9.png] view at source ↗
Figure 10
Figure 10. Figure 10: Numerical results for Experiment 3 (homogeneous 1D advection equation with periodic BCs). Experiment 4. This numerical experiment investigates the advection-diffusion equation with Dirich￾let BCs u(t,xL)=u(t,xR), where c=0. The initial condition is given by u0(x) =exp a 2b x  sin πx l , f(t,x) =0. (6.8) [PITH_FULL_IMAGE:figures/full_fig_p027_10.png] view at source ↗
Figure 11
Figure 11. Figure 11: Numerical results for Experiment 4 (homogeneous 1D advection-diffusion equation with Dirichlet BCs, central scheme). Experiment 5. This numerical experiment considers the advection-diffusion equation subject to pe￾riodic BCs u(t,xL) = u(t,xR) and ux(t,xL) = ux(t,xR), where c = 0. The initial condition is specified as u0(x) =sin 2πx l , f(t,x) =0. (6.10) This initial-boundary value problem admits an exact … view at source ↗
Figure 12
Figure 12. Figure 12: Numerical results for Experiment 4 (homogeneous 1D advection-diffusion equation with Dirichlet BCs, exponential scheme) [PITH_FULL_IMAGE:figures/full_fig_p029_12.png] view at source ↗
Figure 13
Figure 13. Figure 13: Numerical results for Experiment 5 (homogeneous 1D advection-diffusion equation with periodic BCs, central scheme). x u 0 0.2 0.4 0.6 0.8 1 -1 -0.5 0 0.5 1 Exact LCHS-Exp,n=9,m=4 LCHS-Exp,n=10,m=4 LCHS-Exp,n=11,m=4 (a) Fixed m=4 x u 0 0.2 0.4 0.6 0.8 1 -1 -0.5 0 0.5 1 Exact LCHS-Exp,n=10,m=3 LCHS-Exp,n=10,m=4 LCHS-Exp,n=10,m=5 (b) Fixed n=11 [PITH_FULL_IMAGE:figures/full_fig_p030_13.png] view at source ↗
Figure 14
Figure 14. Figure 14: Numerical results for Experiment 5 (homogeneous 1D advection-diffusion equation with periodic BCs, exponential scheme) [PITH_FULL_IMAGE:figures/full_fig_p030_14.png] view at source ↗
Figure 15
Figure 15. Figure 15: Numerical results for Experiment 6 (inhomogeneous 1D advection equation with periodic BCs). Experiment 7. This numerical experiment considers the advection-diffusion equation with Dirichlet BCs u(t,xL)=u(t,xR), where c=0. The initial condition is given by u0(x) =0, f(t,x) =exp a 2b x   e −t+ [PITH_FULL_IMAGE:figures/full_fig_p031_15.png] view at source ↗
Figure 16
Figure 16. Figure 16: Numerical results for Experiment 7 (inhomogeneous 1D advection-diffusion equation with Dirichlet BCs, fixed n=11,m=4) [PITH_FULL_IMAGE:figures/full_fig_p032_16.png] view at source ↗
Figure 17
Figure 17. Figure 17: Numerical results for Experiment 8 (homogeneous 2D diffusion equation with Robin BCs) [PITH_FULL_IMAGE:figures/full_fig_p033_17.png] view at source ↗
Figure 18
Figure 18. Figure 18: Numerical results for Experiment 9 (homogeneous 2D advection-diffusion equation with periodic BCs) [PITH_FULL_IMAGE:figures/full_fig_p034_18.png] view at source ↗
Figure 20
Figure 20. Figure 20: µ1 vs µ0(N = 32) of Eq. (A.10). A.3 Hyperbolic case For the maximum eigenvalue, we set λ=2coshξ and assume xk =Ccosh((k−1)ξ)+Dsinh((k− 1)ξ). Substituting these into the boundary conditions yields the characteristic equation sinh((N+1)ξ)−(µ0+µ1)sinh(Nξ)+µ0µ1 sinh((N−1)ξ)=0, (A.11) which can be rewritten as e (N−1)ξ (e ξ−µ0)(e ξ−µ1)=e −(N−1)ξ (e −ξ−µ0)(e −ξ−µ1). (A.12) [PITH_FULL_IMAGE:figures/full_fig_p03… view at source ↗
read the original abstract

This paper proposes a systematic and explicit quantum circuit framework for solving advection-diffusion equations with boundary conditions, based on the Linear Combination of Hamiltonian Simulations (LCHS) method. By employing the Finite Volume Method (FVM) combined with various flux construction schemes, we elaborate the design of quantum circuits tailored explicitly for Robin boundary conditions (including Dirichlet and Neumann boundary conditions as special cases) and periodic boundary conditions. In contrast to prior works on quantum simulation of advection-diffusion equations, we present a detailed error analysis for the linear combination of unitaries (LCU) induced by the constructed quantum circuits. A comprehensive gate complexity analysis demonstrates the quantum advantages over classical computing in high-dimensional scenarios. We simulate the proposed circuits on a fault-tolerant emulator, and numerical results validate the effectiveness of the proposed framework across homogeneous, inhomogeneous, and high-dimensional cases. The proposed framework is compatible with numerous spatial discretization methods and numerical schemes, extends naturally to other linear PDEs, and establishes a practical foundation for solving large-scale PDE problems on future fault-tolerant quantum computers.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 2 minor

Summary. The paper proposes a systematic quantum circuit framework for solving the advection-diffusion equation with boundary conditions, based on the Linear Combination of Hamiltonian Simulations (LCHS) method. It combines Finite Volume Method (FVM) discretizations with specific flux schemes to construct explicit circuits for Robin (including Dirichlet and Neumann as special cases) and periodic boundary conditions. The manuscript provides a detailed error analysis for the resulting linear combination of unitaries (LCU), a gate complexity analysis claiming quantum advantages in high-dimensional settings, and numerical validation via simulations on a fault-tolerant quantum emulator for homogeneous, inhomogeneous, and high-dimensional cases. The framework is presented as compatible with other spatial discretizations and extensible to other linear PDEs.

Significance. If the LCU error bounds and complexity claims hold, the work offers a concrete bridge between classical FVM schemes and quantum Hamiltonian simulation techniques for PDEs with boundaries, which could enable practical quantum solutions for high-dimensional advection-diffusion problems. Strengths include the explicit circuit constructions for boundary conditions, the emulator-based numerical validation across multiple cases, and the gate-counting analysis that quantifies potential advantages over classical methods.

major comments (2)
  1. [§4] §4 (LCU error analysis): the stated error bound for the linear combination of unitaries must be shown to remain independent of the specific boundary flux parameters (e.g., Robin coefficient α or inhomogeneous terms). If the operator norms or number of summands in the LCU scale with these coefficients, the bound no longer directly controls solution accuracy on the quantum device, undermining the claim that the analysis rigorously supports the framework for general boundary conditions.
  2. [§5] §5 (gate complexity analysis): the scaling comparison to classical methods should explicitly include the overhead from encoding the chosen flux schemes and boundary implementations; without this, the asserted quantum advantage in high-dimensional scenarios rests on an incomplete accounting of total gate cost.
minor comments (2)
  1. [§3] The notation distinguishing the various flux construction schemes for different boundary types could be made more uniform to improve readability.
  2. [Figures] Circuit diagrams in the figures would benefit from explicit labels indicating which gates correspond to the LCHS linear combination coefficients versus the boundary terms.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the detailed and constructive report. The comments highlight important aspects of the LCU error analysis and gate complexity that we address point by point below. We believe the manuscript already contains the core elements needed to support the claims, but we will revise to improve clarity and explicitness where the referee has identified gaps.

read point-by-point responses
  1. Referee: [§4] §4 (LCU error analysis): the stated error bound for the linear combination of unitaries must be shown to remain independent of the specific boundary flux parameters (e.g., Robin coefficient α or inhomogeneous terms). If the operator norms or number of summands in the LCU scale with these coefficients, the bound no longer directly controls solution accuracy on the quantum device, undermining the claim that the analysis rigorously supports the framework for general boundary conditions.

    Authors: We agree that explicit independence from boundary parameters strengthens the result. In the current manuscript, the LCU error bound (Theorem 4.1 and surrounding analysis) is expressed in terms of the operator norm of the full Hamiltonian H, which incorporates the Robin coefficient α and inhomogeneous flux terms via the chosen FVM discretization. Because α enters as a fixed physical parameter (not scaling with system size or dimension), the norm ||H|| remains bounded independently of the discretization parameters for any fixed α. The number of LCU summands is determined by the number of distinct flux operators, which is fixed by the stencil and does not grow with α. We will add a short remark and a short proof sketch in §4 clarifying that the bound holds uniformly for any fixed α and inhomogeneous term, with the dependence on α appearing only through the (bounded) constant ||H||. This is a clarification rather than a substantive change to the analysis. revision: partial

  2. Referee: [§5] §5 (gate complexity analysis): the scaling comparison to classical methods should explicitly include the overhead from encoding the chosen flux schemes and boundary implementations; without this, the asserted quantum advantage in high-dimensional scenarios rests on an incomplete accounting of total gate cost.

    Authors: We accept this observation. The gate-counting analysis in §5 already accounts for the cost of implementing the individual Hamiltonian terms arising from the FVM flux schemes (including boundary contributions) via the LCU decomposition. However, we did not tabulate the additional constant-factor overhead associated with the specific encoding of the Robin/periodic boundary operators. In the revision we will insert an explicit paragraph and a small table in §5 that isolates this overhead (which is O(1) with respect to dimension d and grid size) and shows that it does not alter the asymptotic quantum advantage for high-dimensional problems. The comparison will then be stated with the full gate cost made transparent. revision: yes

Circularity Check

0 steps flagged

No significant circularity; derivation is self-contained via explicit constructions

full rationale

The paper starts from standard finite-volume discretization of the advection-diffusion PDE, applies known LCHS encoding to obtain a linear combination of unitaries, then supplies explicit quantum-circuit constructions for Robin/periodic boundaries together with fresh LCU error bounds and gate-complexity counts. None of these steps reduces by definition or by self-citation to the target result itself; the error analysis is presented as new relative to prior works, and the claimed quantum advantage follows from direct gate counting rather than any fitted parameter or uniqueness theorem imported from the authors' own earlier papers. The framework therefore remains externally falsifiable through the stated circuit implementations and numerical emulations.

Axiom & Free-Parameter Ledger

0 free parameters · 2 axioms · 0 invented entities

The central claim rests on the standard assumptions of the finite volume method for spatial discretization and the applicability of LCHS to the resulting linear operator; no new free parameters or invented entities are introduced in the abstract.

axioms (2)
  • domain assumption The advection-diffusion equation with boundary conditions admits a stable finite-volume discretization whose flux schemes can be expressed as a linear combination of Hamiltonian terms.
    Invoked when mapping the PDE to quantum circuits via LCHS.
  • standard math Standard quantum circuit primitives exist for implementing the linear combination of unitaries arising from the discretized operator.
    Required for the explicit circuit construction and gate-count analysis.

pith-pipeline@v0.9.0 · 5718 in / 1483 out tokens · 40386 ms · 2026-05-19T22:39:32.700665+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

65 extracted references · 65 canonical work pages · 1 internal anchor

  1. [1]

    R. P . Feynman. Simulating physics with computers.International Journal of Theoretical Physics, 21(6):467– 488, 1982

  2. [2]

    D. Deutsch. Quantum theory, the church–turing principle and the universal quantum computer.Proceed- ings of the Royal Society of London. A. Mathematical and Physical Sciences, 400(1818):97–117, 07 1985

  3. [3]

    M. A. Nielsen and I. L. Chuang.Quantum Computation and Quantum Information: 10th Anniversary Edition. Cambridge University Press, Cambridge, UK; New York, USA, 2010

  4. [4]

    P . W. Shor. Polynomial-time algorithms for prime factorization and discrete logarithms on a quantum computer.SIAM Journal on Computing, 26(5):1484–1509, 1997

  5. [5]

    Hallgren

    S. Hallgren. Polynomial-time quantum algorithms for pell’s equation and the principal ideal problem.J. ACM, 54(1), 2007

  6. [6]

    C. H. Bennett and G. Brassard. Quantum cryptography: Public key distribution and coin tossing.Theo- retical Computer Science, 560:7–11, 2014

  7. [7]

    A. W. Harrow, A. Hassidim, and S. Lloyd. Quantum algorithm for linear systems of equations.Phys. Rev. Lett., 103:150502, 2009

  8. [8]

    Andr ´as Gily´en, Y. Su, G. H. Low, and N. Wiebe. Quantum singular value transformation and beyond: ex- ponential improvements for quantum matrix arithmetics. InProceedings of the 51st Annual ACM SIGACT Symposium on Theory of Computing, STOC 2019, pages 193–204, New York, NY, USA, 2019. Association for Computing Machinery

  9. [9]

    Subas ¸ı, R

    Y. Subas ¸ı, R. D. Somma, and D. Orsucci. Quantum algorithms for systems of linear equations inspired by adiabatic quantum computing.Phys. Rev. Lett., 122:060504, 2019

  10. [10]

    Lin and Y

    L. Lin and Y. Tong. Optimal polynomial based quantum eigenstate filtering with application to solving quantum linear systems.Quantum, 4:361, 2020

  11. [11]

    P . C. S. Costa, D. An, Y. R. Sanders, Y. Su, R. Babbush, and D. W. Berry. Optimal scaling quantum linear- systems solver via discrete adiabatic theorem.PRX Quantum, 3:040303, 2022

  12. [12]

    S. Lloyd. Universal quantum simulators.Science, 273:1073–1078, 1996

  13. [13]

    Buluta and F

    I. Buluta and F. Nori. Quantum simulators.Science, 326:108–111, 2009

  14. [14]

    Al ´an, D

    A.-G. Al ´an, D. D. Anthony, J. L. Peter, and H.-G. Martin. Simulated quantum computation of molecular energies.Science, 309(5741):1704–1707, 2005

  15. [15]

    I. M. Georgescu, S. Ashhab, and F. Nori. Quantum simulation.Rev. Mod. Phys., 86:153–185, 2014

  16. [16]

    J.-P . Liu, H. O. Kolden, H. K. Krovi, N. F. Loureiro, K. Trivisa, and A. M. Childs. Efficient quantum algorithm for dissipative nonlinear differential equations.Proc. Natl. Acad. Sci. U.S.A., 118:e2026805118, 2021. 46

  17. [17]

    Sanavio, R

    C. Sanavio, R. Scatamacchia, C. de Falco, and S. Succi. Three carleman routes to the quantum simulation of classical fluids.Phys. Fluids, 36:057143, 2024

  18. [18]

    Gonzalez-Conde, D

    J. Gonzalez-Conde, D. Lewis, S. S. Bharadwaj, and M. Sanz. Quantum carleman linearization efficiency in nonlinear fluid dynamics.Phys. Rev. Res., 7:023254, 2025

  19. [19]

    I. Joseph. Koopman-von neumann approach to quantum simulation of nonlinear classical dynamics. Phys. Rev. Res., 2:043102, 2020

  20. [20]

    Joseph, Y

    I. Joseph, Y. Shi, M. D. Porter, A. R. Castelli, V . I. Geyko, F. R. Graziani, S. B. Libby, and J. L. DuBois. Quantum computing for fusion energy science applications.Physics of Plasmas, 30(1):010501, 2023

  21. [21]

    Giannakis, A

    D. Giannakis, A. Ourmazd, P . Pfeffer, J. Schumacher, and J. Slawinska. Embedding classical dynamics in a quantum computer.Phys. Rev. A, 105:052404, 2022

  22. [22]

    Zhang, Z

    B. Zhang, Z. Lu, Y. Zhao, and Y. Yang. Data-driven quantum koopman method for simulating nonlinear dynamics, 2025. arXiv:2507.21890

  23. [23]

    S. Jin, N. Liu, and Y. Yu. Time complexity analysis of quantum algorithms via linear representations for nonlinear ordinary and partial differential equations.J. Comput. Phys., 487:112149, 2023

  24. [24]

    Succi, W

    S. Succi, W. Itani, C. Sanavio, K. R. Sreenivasan, and R. Steijl. Ensemble fluid simulations on quantum computers.Computers and Fluids, 270:106148, 2024

  25. [25]

    Meng and Y

    Z. Meng and Y. Yang. Quantum computing of fluid dynamics using the hydrodynamic schr ¨odinger equation.Phys. Rev. Res., 5:033182, 2023

  26. [26]

    Z. Meng, J. Zhong, S. Xu, K. Wang, J. Chen, F. Jin, X. Zhu, Y. Gao, Y. Wu, C. Zhang, N. Wang, Y. Zou, A. Zhang, Z. Cui, F. Shen, Z. Bao, Z. Zhu, Z. Tan, T. Li, P . Zhang, S. Xiong, H. Li, Q. Guo, Z. Wang, C. Song, H. Wang, and Y. Yang. Simulating unsteady flows on a superconducting quantum processor. Commun. Phys., 7:349, 2024

  27. [27]

    Xue, X.-F

    C. Xue, X.-F. Xu, X.-N. Zhuang, T.-P . Sun, Y.-J. Wang, M.-Y. Tan, C.-C. Ye, H.-Y. Liu, Y.-C. Wu, Z.-Y. Chen, and G.-P . Guo. Quantum homotopy analysis method with quantum-compatible linearization for nonlinear partial differential equations.Sci. China-Phys. Mech. Astron., 68:104702, 2025

  28. [28]

    S. S. Bharadwaj, B. Nadiga, S. Eidenbenz, and K. R. Sreenivasan. Quantum homotopy algorithm for solving nonlinear pdes and flow problems, 2025. arXiv:2512.21033

  29. [29]

    E. Choi, J. E. Kim, X. Lu, and Y. Wang. Lindbladian homotopy analysis method to solve nonlinear partial differential equations, 2026. arXiv:2604.18924

  30. [30]

    D. W. Berry. High-order quantum algorithm for solving linear differential equations.Journal of Physics A: Mathematical and Theoretical, 47(10):105301, 2014

  31. [31]

    D. W. Berry, A. M. Childs, A. Ostrander, and G. Wang. Quantum algorithm for linear differential equa- tions with exponentially improved dependence on precision.Communications in Mathematical Physics, 356(3):1057–1081, oct 2017

  32. [32]

    A. M. Childs and J.-P . Liu. Quantum spectral methods for differential equations.Communications in Mathematical Physics, 375:1427–1457, 2020

  33. [33]

    Febrianto, Y

    E. Febrianto, Y. Wang, B. Liu, M. Ortiz, and F. Cirak. A quantum spectral method for non-periodic boundary value problems.Computer Methods in Applied Mechanics and Engineering, 457:118934, 2026

  34. [34]

    S. Jin, N. Liu, and Y. Yu. Quantum simulation of partial differential equations: Applications and detailed analysis.Phys. Rev. A, 108:032603, 2023

  35. [35]

    S. Jin, N. Liu, and Y. Yu. Quantum simulation of partial differential equations via schr ¨odingerization. Phys. Rev. Lett., 133:230602, 2024

  36. [36]

    S. Jin, X. Li, N. Liu, and Y. Yu. Quantum simulation for quantum dynamics with artificial boundary conditions.SIAM Journal on Scientific Computing, 46(4):B403–B421, 2024

  37. [37]

    S. Jin, X. Li, N. Liu, and Y. Yu. Quantum simulation for partial differential equations with physical boundary or interface conditions.Journal of Computational Physics, 498:112707, 2024

  38. [38]

    Jin and N

    S. Jin and N. Liu. Analog quantum simulation of partial differential equations.Quantum Science and Technology, 9(3):035047, 2024

  39. [39]

    S. Jin, N. Liu, and C. Ma. Quantum simulation of maxwell’s equations via schr ¨odingerisation.ESAIM- Math. Model. Numer. Anal., 58:1853–1879, 2024

  40. [40]

    S. Jin, N. Liu, and Y. Yu. Quantum simulation of the fokker–planck equation via schr ¨odingerization. Communications in Computational Physics, 39(4):969–1001, 2026

  41. [41]

    An, J.-P

    D. An, J.-P . Liu, and L. Lin. Linear combination of hamiltonian simulation for nonunitary dynamics with optimal state preparation cost.Phys. Rev. Lett., 131:150603, 2023

  42. [42]

    D. An, A. M. Childs, and L. Lin. Quantum algorithm for linear non-unitary dynamics with near-optimal dependence on all parameters, 2023. arXiv:2312.03916

  43. [43]

    Yang and J.-P

    S. Yang and J.-P . Liu. Circuit-efficient randomized quantum simulation of non-unitary dynamics with observable-driven and symmetry-aware designs, 2025. arXiv:2509.08030

  44. [44]

    Lu, H.-E

    R. Lu, H.-E. Li, Z. Liu, and J.-P . Liu. Infinite-dimensional extension of the linear combination of hamilto- nian simulation: Theorems and applications, 2025. arXiv:2502.19688

  45. [45]

    Huang and D

    X. Huang and D. An. Fourier transform-based linear combination of hamiltonian simulation, 2025. 47 arXiv:2508.19596

  46. [46]

    G. H. Low and R. D. Somma. Optimal quantum simulation of linear non-unitary dynamics, 2025. arXiv:2508.19238

  47. [47]

    Z. Meng, L. Chen, J.-P . Liu, and G. He. Toward end-to-end quantum simulation of rapidly distorted turbulence.Journal of Computational Physics, 558:114888, 2026

  48. [48]

    Novikau and I

    I. Novikau and I. Joseph. Quantum algorithm for the advection-diffusion equation and the koopman-von neumann approach to nonlinear dynamical systems.Computer Physics Communications, 309:109498, 2025

  49. [49]

    Y. Sato, R. Kondo, I. Hamamura, T. Onodera, and N. Yamamoto. Hamiltonian simulation for hyperbolic partial differential equations by scalable quantum circuits.Phys. Rev. Res., 6:033246, 2024

  50. [50]

    J. Hu, S. Jin, N. Liu, and L. Zhang. Quantum circuits for partial differential equations via Schr¨odingerisation.Quantum, 8:1563, 2024

  51. [51]

    S. Jin, N. Liu, and Y. Yu. Quantum circuits for the heat equation with physical boundary conditions via schr¨odingerization.Journal of Computational Physics, 538:114138, 2025

  52. [52]

    A. N. Soklakov and R. Schack. Efficient state preparation for a register of quantum bits.Phys. Rev. A, 73:012307, 2006

  53. [53]

    S ¨uli and D

    E. S ¨uli and D. F. Mayers.An Introduction to Numerical Analysis. Cambridge University Press, Cambridge, 2003

  54. [54]

    L. Lin. Lecture notes on quantum algorithms for scientific computation, 2022. arXiv:2201.08309

  55. [55]

    A. M. Childs, Y. Su, M. C. Tran, N. Wiebe, and S. Zhu. Theory of trotter error with commutator scaling. Phys. Rev. X, 11:011020, 2021

  56. [56]

    D. N. DE G. Allen and R. V . Southwell. Relaxation methods applied to determine the motion, in two dimensions, of a viscous fluid past a fixed cylinder.The Quarterly Journal of Mechanics and Applied Mathe- matics, 8(2):129–145, 01 1955

  57. [57]

    D. B. Spalding. A novel finite difference formulation for differential expressions involving both first and second derivatives.International Journal for Numerical Methods in Engineering, 4(4):551–559, 1972

  58. [58]

    Barenco, C

    A. Barenco, C. H. Bennett, R. Cleve, D. P . DiVincenzo, N. Margolus, P . Shor, T. Sleator, J. A. Smolin, and H. Weinfurter. Elementary gates for quantum computation.Phys. Rev. A, 52:3457–3467, 1995

  59. [59]

    R. Vale, T. M. D. Azevedo, I. C. S. Ara ´ujo, I. F. Araujo, and A. J. da Silva. Circuit decomposition of multicontrolled special unitary single-qubit gates.IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, 43(3):802–811, 2024

  60. [60]

    E. C. R. Rosa, E. I. Duzzioni, and R. de Santiago. Optimizing Gate Decomposition for High-Level Quan- tum Programming.Quantum, 9:1659, 2025

  61. [61]

    A. J. da Silva and D. K. Park. Linear-depth quantum circuits for multiqubit controlled gates.Phys. Rev. A, 106:042602, 2022

  62. [62]

    Qpanda: high- performance quantum computing framework for multiple application scenarios, 2022

    Dou M, Zou T, Fang Y, Wang J, Zhao D, Yu L, Chen B, Guo W, Li Y, Chen Z, and Guo G. Qpanda: high- performance quantum computing framework for multiple application scenarios, 2022. arXiv:2212.14201

  63. [63]

    Preskill

    J. Preskill. Quantum Computing in the NISQ era and beyond.Quantum, 2:79, 2018

  64. [64]

    W.-C. Yueh. Eigenvalues of several tridiagonal matrices.Applied Mathematics E-Notes, 5:66–74, 2005

  65. [65]

    A. R. Willms. Analytic results for the eigenvalues of certain tridiagonal matrices.SIAM Journal on Matrix Analysis and Applications, 30(2):639–656, 2008