Path integral Monte Carlo

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Path integral Monte Carlo (PIMC) is a quantum Monte Carlo method used to solve quantum statistical mechanics problems numerically within the path integral formulation. The application of Monte Carlo methods to path integral simulations of condensed matter systems was first pursued in a key paper by John A. Barker. [1] [2]

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The method is typically (but not necessarily) applied under the assumption that symmetry or antisymmetry under exchange can be neglected, i.e., identical particles are assumed to be quantum Boltzmann particles, as opposed to fermion and boson particles. The method is often applied to calculate thermodynamic properties [3] such as the internal energy, [4] heat capacity, [5] or free energy. [6] [7] As with all Monte Carlo method based approaches, a large number of points must be calculated.

In principle, as more path descriptors are used (these can be "replicas", "beads," or "Fourier coefficients," depending on what strategy is used to represent the paths), [8] the more quantum (and the less classical) the result is. However, for some properties the correction may cause model predictions to initially become less accurate than neglecting them if a small number of path descriptors are included. At some point the number of descriptors is sufficiently large and the corrected model begins to converge smoothly to the correct quantum answer. [5] Because it is a statistical sampling method, PIMC can take anharmonicity fully into account, and because it is quantum, it takes into account important quantum effects such as tunneling and zero-point energy (while neglecting the exchange interaction in some cases). [6]

The basic framework was originally formulated within the canonical ensemble, [9] but has since been extended to include the grand canonical ensemble [10] and the microcanonical ensemble. [11] Its use has been extended to fermion systems [12] as well as systems of bosons. [13]

An early application was to the study of liquid helium. [14] Numerous applications have been made to other systems, including liquid water [15] and the hydrated electron. [16] The algorithms and formalism have also been mapped onto non-quantum mechanical problems in the field of financial modeling, including option pricing. [17]

See also

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References

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  2. Cazorla, Claudio; Boronat, Jordi (2017). "Simulation and understanding of atomic and molecular quantum crystals". Reviews of Modern Physics. 89 (3): 035003. arXiv: 1605.05820 . Bibcode:2017RvMP...89c5003C. doi:10.1103/RevModPhys.89.035003 . Retrieved May 13, 2022.
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  13. Dornheim, Tobias (2020). "Path-integral Monte Carlo simulations of quantum dipole systems in traps: Superfluidity, quantum statistics, and structural properties". Physical Review A. 102 (2): 023307. arXiv: 2005.03881 . Bibcode:2020PhRvA.102b3307D. doi:10.1103/PhysRevA.102.023307. S2CID   218570984 . Retrieved May 13, 2022.
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  15. Noya, Eva G.; Sese, Luis M.; Ramierez, Rafael; McBride, Carl; Conde, Maria M.; Vega, Carlos (2011). "Path integral Monte Carlo simulations for rigid rotors and their application to water". Molecular Physics. 109 (1): 149–168. arXiv: 1012.2310 . Bibcode:2011MolPh.109..149N. doi:10.1080/00268976.2010.528202. S2CID   44166408 . Retrieved May 12, 2022.
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  17. Capuozzo, Pietro; Panella, Emanuele; Gherardini, Tancredi Schettini; Vvedensky, Dmitri D. (2021). "Path integral Monte Carlo method for option pricing". Physica A: Statistical Mechanics and Its Applications. 581: 126231. Bibcode:2021PhyA..58126231C. doi:10.1016/j.physa.2021.126231 . Retrieved May 13, 2022.