Related papers: Simulating the Schroedinger functional with two ps…
Microscopic models of classical degrees of freedom coupled to non-interacting fermions occur in many different contexts. Prominent examples from solid state physics are descriptions of colossal magnetoresistance manganites and diluted…
A parallelizable SSOR preconditioning scheme for Krylov subspace iterative solvers in lattice QCD applications involving Wilson fermions is presented. In actual Hybrid Monte Carlo and quark propagator calculations it helps to reduce the…
The standard method to calculate non-perturbatively the evolution of the running coupling of a SU(N) gauge theory is based on the Schr\"odinger functional (SF). In this paper we construct a family of boundary fields for general values of N…
We present first, exploratory results of a hybrid Monte-Carlo algorithm for dynamical, n_f=2, four-dimensional QCD with overlap fermions. As expected, the computational requirements are typically two orders of magnitude larger for the…
We perform hybrid Monte Carlo (HMC) simulatons of two flavors QCD with the optimal domain-wall fermion (ODWF) on the 16^3 x 32 lattice (with lattice spacing a ~ 0.1 fm), for eight sea-quark masses corresponding to pion masses in the range…
We present a general technique for addressing sign problems that arise in Monte Carlo simulations of field theories. This method deforms the domain of the path integral to a manifold in complex field space that maximizes the average sign…
An improved algorithm is proposed for Monte Carlo methods to study fermion systems interacting with adiabatical fields. To obtain a weight for each Monte Carlo sample with a fixed configuration of adiabatical fields, a series expansion…
Simulations with 2+1 flavors of domain wall fermions provide us with the opportunity to compare the lattice data directly to the predictions of continuum chiral perturbation theory, up to corrections from the residual chiral symmetry…
We present a detailed design of a (P)HMC simulation algorithm for N_f = 2 + 1 + 1 maximally twisted Wilson quark flavours. The algorithm retains even/odd and mass-shift preconditionings combined with multiple Molecular Dynamics time scales…
We present a universal quantum Monte Carlo algorithm for simulating arbitrary high-spin (spin greater than 1/2) Hamiltonians, based on the recently developed permutation matrix representation (PMR) framework. Our approach extends a…
A possible solution of the notorious sign problem preventing direct Monte Carlo calculations for systems with non-zero chemical potential is to deform the integration region in the complex plane to a Lefschetz thimble. We investigate this…
We present a multi-level algorithm for the solution of five dimensional chiral fermion formulations, including domain wall and Mobius Fermions. The algorithm operates on the red-black preconditioned Hermitian operator, and directly…
In this contribution, a first look at simulations using maximally twisted mass Wilson fermions at the physical point is presented. A lattice action including clover and twisted mass terms is presented and the Monte Carlo histories of one…
We consider the two-dimensional N=(2,2) Wess-Zumino model with a cubic superpotential at weak and intermediate couplings. Refined algorithms allow for the extraction of reliable masses in a region where perturbation theory no longer…
UKQCD's dynamical fermion project uses the Generalised Hybrid Monte-Carlo (GHMC) algorithm to generate QCD gauge configurations for a non-perturbatively O(a) improved Wilson action with two degenerate sea-quark flavours. We describe our…
We investigate the performance of the hybrid Monte Carlo algorithm in updating non-trivial global topological structures. We find that the hybrid Monte Carlo algorithm has serious problems decorrelating the global topological charge. This…
We show that it is possible to construct a lattice Schroedinger functional for standard Wilson fermions, where the expectation values of ${\cal R}_5$-even operators are O($a$) improved, up to terms coming from the boundaries.
Results on the computational efficiency of 2-flavor staggered Wilson fermions compared to usual Wilson fermions in a quenched lattice QCD simulation on $16^3\times32$ lattice at $\beta=6$ are reported. We compare the cost of inverting the…
To evaluate the effectiveness of machine learning in systems with competing interactions, we developed a self-learning quantum Monte Carlo (SLQMC) method to simulate the phase transition in the classical Holstein-spin-fermion model. In…
We simulate one-flavor QCD with standard Wilson fermions at finite temperature by the rational hybrid Monte Carlo algorithm. In the heavy quark region when we decrease the quark mass there is an endpoint which terminates the first order…