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Related papers: Product Formulas for Exponentials of Commutators

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We introduce a $0.611$-approximation algorithm for Quantum MaxCut and a $\frac{1+\sqrt{5}}{4} \approx 0.809$-approximation algorithm for the EPR Hamiltonian of [arXiv:2209.02589]. A novel ingredient in both of these algorithms is to…

Quantum Physics · Physics 2025-04-22 Anuj Apte , Eunou Lee , Kunal Marwaha , Ojas Parekh , James Sud

Recently Quantum Computation has generated a lot of interest due to the discovery of a quantum algorithm which can factor large numbers in polynomial time. The usefulness of a quantum com puter is limited by the effect of errors. Simulation…

Quantum Physics · Physics 2007-05-23 Kevin M. Obenland , Alvin M. Despain

The discovery of derivatives and integrals was a tremendous leap in scientific knowledge and completely revolutionized many fields, including mathematics, physics, and engineering. The existence of higher-order derivatives means better…

Quantum Physics · Physics 2023-05-16 Basanta R. Pahari , Sagar Bhat , Siri Davidi , William Oates

Kronecker products of unitary Fourier matrices play important role in solving multilevel circulant systems by a multidimensional Fast Fourier Transform. They are also special cases of complex Hadamard (Zeilinger) matrices arising in many…

Rings and Algebras · Mathematics 2010-11-22 Wojciech Tadej

The unitary evolution can be represented by a finite product of exponential operators. It leads to a perturbative expression of the density operator of a close system. Based on the perturbative expression scheme, we present a entanglement…

Quantum Physics · Physics 2009-11-06 X. X. Yi , C. P. Sun

We introduce a method for calculating individual elements of matrix functions. Our technique makes use of a novel series expansion for the action of matrix functions on basis vectors that is memory efficient even for very large matrices. We…

Computational Physics · Physics 2021-11-18 Lev Barash , Stefan Güttel , Itay Hen

Given the first 20-100 coefficients of a typical generating function of the type that arises in many problems of statistical mechanics or enumerative combinatorics, we show that the method of differential approximants performs surprisingly…

Statistical Mechanics · Physics 2016-10-12 Anthony J Guttmann

Quantum computing has emerged as a promising alternative for solving combinatorial optimization problems. The standard approach for encoding optimization problems on quantum processing units (QPUs) involves transforming them into their…

Emerging Technologies · Computer Science 2025-10-15 Meerzhan Kanatbekova , Vincenzo De Maio , Ivona Brandic

An approach is suggested defining effective sums of divergent series in the form of self-similar exponential approximants. The procedure of constructing these approximants from divergent series with arbitrary noninteger powers is developed.…

Statistical Mechanics · Physics 2009-10-31 V. I. Yukalov , S. Gluzman

We propose an efficient algorithmic framework for time domain circuit simulation using exponential integrator. This work addresses several critical issues exposed by previous matrix exponential based circuit simulation research, and makes…

Computational Engineering, Finance, and Science · Computer Science 2016-11-17 Hao Zhuang , Wenjian Yu , Ilgweon Kang , Xinan Wang , Chung-Kuan Cheng

An algorithm is presented which computes a translationally invariant matrix product state approximation of the ground state of an infinite 1D system; it does this by embedding sites into an approximation of the infinite ``environment'' of…

Other Condensed Matter · Physics 2008-08-18 Gregory M. Crosswhite , Andrew C. Doherty , Guifre Vidal

It is known that commutators of commutators can be written as products of cubes, with the current upper bound on the number of cubes being 60. We discuss how proofs extracted via coset enumeration can be used to investigate this problem,…

Group Theory · Mathematics 2015-07-30 Colin Ramsay

We give explicit and asymptotic lower bounds for the quantity $|e^{s/t}-M/N|$ by studying a generalized continued fraction expansion of $e^{s/t}$. In cases $|s|\geq 3$ we improve existing results by extracting a large common factor from the…

Number Theory · Mathematics 2016-09-23 Kalle Leppälä , Tapani Matala-aho , Topi Törmä

We provide an exact formula for the complex exponents in the modular product expansion of the modular units, and deduce a characterization of the modular units in terms of the growth of these exponents, answering a question of W. Kohnen.

Number Theory · Mathematics 2007-05-23 Amanda Folsom

Compositional Explanations is a method for identifying logical formulas of concepts that approximate the neurons' behavior. However, these explanations are linked to the small spectrum of neuron activations (i.e., the highest ones) used to…

Machine Learning · Computer Science 2023-10-31 Biagio La Rosa , Leilani H. Gilpin , Roberto Capobianco

Hamiltonian simulation is a promising application for quantum computers to achieve a quantum advantage. We present classical algorithms based on tensor network methods to optimize quantum circuits for this task. We show that, compared to…

Quantum Physics · Physics 2023-06-05 Conor Mc Keever , Michael Lubasch

To find moments of various estimators related to Autoregressive models of Statistics, one first needs the cumulants of products of two Normally distributed random variables. The purpose of this article is to derive the corresponding…

Statistics Theory · Mathematics 2015-06-18 Clarence Kalitsi , Jan Vrbik

A classical t-tensor product expander is a natural way of formalising correlated walks of t particles on a regular expander graph. A quantum t-tensor product expander is a completely positive trace preserving map that is a straightforward…

Quantum Physics · Physics 2018-09-07 Pranab Sen

Algorithms based on non-unitary evolution have attracted much interest for ground state preparation on quantum computers. One recently proposed method makes use of ancilla qubits and controlled unitary operators to implement weak…

Quantum Physics · Physics 2025-12-25 Tobias Stollenwerk , Stuart Hadfield

We propose an iterative estimating equations procedure for analysis of longitudinal data. We show that, under very mild conditions, the probability that the procedure converges at an exponential rate tends to one as the sample size…

Statistics Theory · Mathematics 2007-12-18 Jiming Jiang , Yihui Luan , You-Gan Wang