Trotter error time scaling separation via commutant decomposition
- URL: http://arxiv.org/abs/2409.16634v1
- Date: Wed, 25 Sep 2024 05:25:50 GMT
- Title: Trotter error time scaling separation via commutant decomposition
- Authors: Yi-Hsiang Chen,
- Abstract summary: Suppressing the Trotter error in dynamical quantum simulation typically requires running deeper circuits.
We introduce a general framework of commutant decomposition that separates disjoint error components that have fundamentally different scaling with time.
We show that this formalism not only straightforwardly reproduces previous results but also provides a better error estimate for higher-order product formulas.
- Score: 6.418044102466421
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Suppressing the Trotter error in dynamical quantum simulation typically requires running deeper circuits, posing a great challenge for noisy near-term quantum devices. Studies have shown that the empirical error is usually much smaller than the one suggested by existing bounds, implying the actual circuit cost required is much less than the ones based on those bounds. Here, we improve the estimate of the Trotter error over existing bounds, by introducing a general framework of commutant decomposition that separates disjoint error components that have fundamentally different scaling with time. In particular we identify two error components that each scale as $\mathcal{O}(t^{p+1}/r^p)$ and $\mathcal{O}(t^p/r^p)$ for a $p$th-order product formula evolving to time $t$ using $r$ partitions. Under a fixed step size $t/r$, it implies one would scale linearly with time $t$ and the other would be constant of $t$. We show that this formalism not only straightforwardly reproduces previous results but also provides a better error estimate for higher-order product formulas. We demonstrate the improvement both analytically and numerically. We also apply the analysis to observable error relating to the heating in Floquet dynamics and thermalization, which is of independent interest.
Related papers
- Convergence Rate Analysis of LION [54.28350823319057]
LION converges iterations of $cal(sqrtdK-)$ measured by gradient Karush-Kuhn-T (sqrtdK-)$.
We show that LION can achieve lower loss and higher performance compared to standard SGD.
arXiv Detail & Related papers (2024-11-12T11:30:53Z) - Two-Timescale Linear Stochastic Approximation: Constant Stepsizes Go a Long Way [12.331596909999764]
We investigate it constant stpesize schemes through the lens of Markov processes.
We derive explicit geometric and non-asymptotic convergence rates, as well as the variance and bias introduced by constant stepsizes.
arXiv Detail & Related papers (2024-10-16T21:49:27Z) - Exponentially Reduced Circuit Depths Using Trotter Error Mitigation [0.0]
Richardson and extrapolation have been proposed to mitigate the Trotter error incurred by use of these formulae.
This work provides an improved, rigorous analysis of these techniques for calculating time-evolved expectation values.
We demonstrate that, to achieve error $epsilon$ in a simulation of time $T$ using a $ptextth$-order product formula with extrapolation, circuits of depths $Oleft(T1+1/p textrmpolylog (1/epsilon)right)$ are sufficient.
arXiv Detail & Related papers (2024-08-26T16:08:07Z) - Scaling Laws in Linear Regression: Compute, Parameters, and Data [86.48154162485712]
We study the theory of scaling laws in an infinite dimensional linear regression setup.
We show that the reducible part of the test error is $Theta(-(a-1) + N-(a-1)/a)$.
Our theory is consistent with the empirical neural scaling laws and verified by numerical simulation.
arXiv Detail & Related papers (2024-06-12T17:53:29Z) - Trotter error with commutator scaling for the Fermi-Hubbard model [0.0]
We derive higher-order error bounds with small prefactors for a general Trotter product formula.
We then apply these bounds to the real-time quantum time evolution operator governed by the Fermi-Hubbard Hamiltonian.
arXiv Detail & Related papers (2023-06-18T17:27:12Z) - Scaling of errors in digitized counterdiabatic driving [0.0]
We study errors caused by digitization of shortcuts to adiabaticity by counterdiabatic driving.
We find possibility of error scaling $mathcalO(M-2)$ with the number of time slices $M$, whereas worse error scaling $mathcalO(M-1)$ is predicted in the conventional theory of the first-order Suzuki-Trotter decomposition.
arXiv Detail & Related papers (2023-03-07T20:56:14Z) - Self-healing of Trotter error in digital adiabatic state preparation [52.77024349608834]
We prove that the first-order Trotterization of a complete adiabatic evolution has a cumulative infidelity that scales as $mathcal O(T-2 delta t2)$ instead of $mathcal O(T2delta t2)$ expected from general Trotter error bounds.
This result suggests a self-healing mechanism and explains why, despite increasing $T$, infidelities for fixed-$delta t$ digitized evolutions still decrease for a wide variety of Hamiltonians.
arXiv Detail & Related papers (2022-09-13T18:05:07Z) - Uniform observable error bounds of Trotter formulae for the semiclassical Schrödinger equation [0.0]
We show that the computational cost for a class of observables can be much lower than the state-of-the-art bounds.
We improve the additive observable error bounds to uniform-in-$h$ observable error bounds.
This is, to our knowledge, the first uniform observable error bound for semiclassical Schr"odinger equation.
arXiv Detail & Related papers (2022-08-16T21:34:49Z) - Average-case Speedup for Product Formulas [69.68937033275746]
Product formulas, or Trotterization, are the oldest and still remain an appealing method to simulate quantum systems.
We prove that the Trotter error exhibits a qualitatively better scaling for the vast majority of input states.
Our results open doors to the study of quantum algorithms in the average case.
arXiv Detail & Related papers (2021-11-09T18:49:48Z) - Hamiltonian simulation with random inputs [74.82351543483588]
Theory of average-case performance of Hamiltonian simulation with random initial states.
Numerical evidence suggests that this theory accurately characterizes the average error for concrete models.
arXiv Detail & Related papers (2021-11-08T19:08:42Z) - Quantum Algorithms for Simulating the Lattice Schwinger Model [63.18141027763459]
We give scalable, explicit digital quantum algorithms to simulate the lattice Schwinger model in both NISQ and fault-tolerant settings.
In lattice units, we find a Schwinger model on $N/2$ physical sites with coupling constant $x-1/2$ and electric field cutoff $x-1/2Lambda$.
We estimate observables which we cost in both the NISQ and fault-tolerant settings by assuming a simple target observable---the mean pair density.
arXiv Detail & Related papers (2020-02-25T19:18:36Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.