English
Related papers

Related papers: Local Basis Transformation to Mitigate Negative Si…

200 papers

Lattice field theory with the $\theta$ term suffers from the sign problem. The sign problem appears as flattening of the free energy. As an alternative to the conventional method, the Fourier transform method (FTM), we apply the maximum…

High Energy Physics - Lattice · Physics 2016-09-01 Masahiro Imachi , Yasuhiko Shinno , Hiroshi Yoneyama

Lithium is a typical quantum solid, characterized by cubic structures at ambient pressure. As the pressure increases, it forms more complex structures and undergoes a metal-to-semiconductor transformation, complicating theoretical and…

Materials Science · Physics 2025-06-24 Qi Zhang , Xiaoyang Wang , Rong Shi , Xinguo Ren , Han Wang , Lei Wang

Estimating spectral gaps of quantum many-body Hamiltonians is a highly challenging computational task, even under assumptions of locality and translation-invariance. Yet, the quest for rigorous gap certificates is motivated by their broad…

Quantum Physics · Physics 2026-04-15 Kshiti Sneh Rai , Ilya Kull , Patrick Emonts , Jordi Tura , Norbert Schuch , Flavio Baccari

A $\theta$ term in lattice field theory causes the sign problem in Monte Carlo simulations. This problem can be circumvented by Fourier-transforming the topological charge distribution $P(Q)$. This strategy, however, has a limitation,…

High Energy Physics - Lattice · Physics 2016-09-01 Masahiro Imachi , Yasuhiko Shinno , Hiroshi Yoneyama

In this talk we show how the sign problem, occurring in dynamical simulations of random matrices at nonzero chemical potential, can be avoided by judiciously combining matrices into subsets. One can prove that these subsets have real and…

High Energy Physics - Lattice · Physics 2011-11-22 Jacques C. R. Bloch

Several studies have emphasized the impact of long-range Coulomb interactions in lattice fermions, yet conventional Auxiliary Field Quantum Monte Carlo (QMC) methods face limitations due to their reliance on positive definite interaction…

Strongly Correlated Electrons · Physics 2024-12-09 Mohammad-Sadegh Vaezi , Davoud Nasr Esfahani

We demonstrate the quantum mean estimation algorithm on Euclidean lattice field theories. This shows a quadratic advantage over Monte Carlo methods which persists even in presence of a sign problem, and is insensitive to critical slowing…

High Energy Physics - Lattice · Physics 2023-06-28 Erik J. Gustafson , Henry Lamm , Judah Unmuth-Yockey

In this paper, we consider spin systems in three spatial dimensions, and prove that the local Hamiltonian problem for 3D lattices with face-centered cubic unit cells, 4-local translationally-invariant interactions between spin-3/2 particles…

Quantum Physics · Physics 2017-11-27 Johannes Bausch , Stephen Piddock

A fundamental open issue in physics is whether and how the fermion sign problem in quantum Monte Carlo (QMC) simulations can be solved generically. Here, we show that Majorana-time-reversal (MTR) symmetries can provide a unifying principle…

Strongly Correlated Electrons · Physics 2016-12-26 Zi-Xiang Li , Yi-Fan Jiang , Hong Yao

We explore different ways of incorporating accurate trial wave functions into free projection auxiliary field quantum Monte Carlo (fp-AFQMC). Trial states employed include coupled cluster singles and doubles, multi-Slater, and symmetry…

Chemical Physics · Physics 2021-04-15 Ankit Mahajan , Sandeep Sharma

Recently, there has been considerable interest in solving optimization problems by mapping these onto a binary representation, sparked mostly by the use of quantum annealing machines. Such binary representation is reminiscent of a discrete…

Quantum Physics · Physics 2021-07-30 Elisabetta Valiante , Maritza Hernandez , Amin Barzegar , Helmut G. Katzgraber

The canonical partition function approach was designed to avoid the overlap problem that affects the lattice simulations of nuclear matter at high density. The method employs the projections of the quark determinant on a fix quark number…

High Energy Physics - Lattice · Physics 2010-01-21 Xiangfei Meng , Anyi Li , Andrei Alexandru , Keh-Fei Liu

The relaxation of binary spins to analog values has been the subject of much debate in the field of statistical physics, neural networks, and more recently quantum computing, notably because the benefits of using an analog state for finding…

Chaotic Dynamics · Physics 2019-02-06 Timothee Leleu , Yoshihisa Yamamoto , Peter L. McMahon , Kazuyuki Aihara

Numerical simulations of lattice quantum field theories whose continuum counterparts possess classical solutions with non-trivial topology face a severe critical slowing down as the continuum limit is approached. Standard Monte-Carlo…

High Energy Physics - Lattice · Physics 2018-08-01 Claudio Bonati , Massimo D'Elia

In lattice field theory, the interactions of elementary particles can be computed via high-dimensional integrals. Markov-chain Monte Carlo (MCMC) methods based on importance sampling are normally efficient to solve most of these integrals.…

High Energy Physics - Lattice · Physics 2020-02-18 Tobias Hartung , Karl Jansen , Hernan Leövey , Julia Volmer

We develop a continuous-time quantum Monte Carlo (CTQMC) method for quantum impurities coupled to interacting quantum wires described by a Tomonaga-Luttinger liquid. The method is negative-sign free for any values of the Tomonaga-Luttinger…

Strongly Correlated Electrons · Physics 2015-06-19 K. Hattori , A. Rosch

Lattice simulations of non-zero density QCD introduce the so-called sign problem (complex or negative probabilities), which invalidates importance sampling methods. To circumvent this, we use the Complex Langevin Equation (CLE), to measure…

High Energy Physics - Lattice · Physics 2023-03-01 Michael W. Hansen , Dénes Sexty

Simulating quantum many-body systems is crucial for advancing physics but poses substantial challenges for classical computers. Quantum simulations overcome these limitations, with analog simulators offering unique advantages over digital…

Quantum Physics · Physics 2025-01-30 Rui-Cheng Guo , Yanwu Gu , Dong E. Liu

We propose a projection approach to perform quantum Monte Carlo (QMC) simulation on the infinite-$U$ Hubbard model at some integer fillings where either it is sign problem free or surprisingly has an algebraic sign structure -- a power law…

Strongly Correlated Electrons · Physics 2021-12-28 Yunqing Ouyang , Xiao Yan Xu

Analog models of quantum information processing, such as adiabatic quantum computation and analog quantum simulation, require the ability to subject a system to precisely specified Hamiltonians. Unfortunately, the hardware used to implement…

Quantum Physics · Physics 2014-02-25 Kevin C. Young , Robin Blume-Kohout , Daniel A. Lidar