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Accelerating Fermionic Molecular Dynamics
| Content Provider | Semantic Scholar |
|---|---|
| Author | Clark, Matthew A. Kennedy, A. D. |
| Copyright Year | 2004 |
| Abstract | For over fifteen years the algorithm of choice for generating lattice field theory configurations including the dynamical effect of fermions has been Hybrid Monte Carlo (HMC) [1]. Unfortunately the cost of this algorithm increases rapidly as the fermion mass m decreases; in order to keep the HMC acceptance rate Pacc constant the molecular dynamics integration step size δτ has to be reduced, and for molecular dynamics trajectories of length τ = 1 this corresponds directly to an increased number of molecular dynamics integration steps and hence larger cost. This required decrease in step size is because of the breakdown of symmetric symplectic integrators. For light dynamical fermions there is an instability for a few isolated light fermion modes, whose frequency is well separated from the bulk of the modes. This instability is seen to be directly responsible for the exponential decrease of HMC acceptance with integration step size above some critical value. We introduce a method for reducing the severity of this problem by reducing the highest “effective frequency” of the fermionic modes, or equivalently of decreasing the magnitude of the fermionic contribution to the force acting on the gauge fields. The basic idea follows the suggestion of Hasenbusch [2] to split the fermionic action into two parts, and to introduce separate pseudofermion fields for each part. Our approach can be easily generalised to an arbitrary number of pseudofermion fields. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://arxiv.org/pdf/hep-lat/0409134v1.pdf |
| Alternate Webpage(s) | http://www2.ccs.tsukuba.ac.jp/workshop/ilft04/presen/Kennedy.pdf |
| Alternate Webpage(s) | http://arxiv.org/pdf/hep-lat/0409134v2.pdf |
| Alternate Webpage(s) | http://cds.cern.ch/record/794209/files/0409134.pdf |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Algorithm Disintegration (morphologic abnormality) Hybrid Memory Cube Hybrid Monte Carlo Instability Large Lattice field theory Leucaena pulverulenta Molecular dynamics Monte Carlo method Quantum field theory Symplectic integrator Time complexity |
| Content Type | Text |
| Resource Type | Article |
