Single classical field description of interacting scalar fields
2022 (Engelska)Ingår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 105, nr 3, artikel-id 036012Artikel i tidskrift (Refereegranskat) Published
Abstract [en]
We test the degree to which interacting Bosonic systems can be approximated by a classical field as total occupation number is increased. This is done with our publicly available code repository, QIBS, a new massively parallel solver for these systems. We use a number of toy models well studied in the literature and track when the classical field description admits quantum corrections, called the quantum breaktime. This allows us to test claims in the literature regarding the rate of convergence of these systems to the classical evolution. We test a number of initial conditions, including coherent states, number eigenstates, and field number states. We find that of these initial conditions, only number eigenstates do not converge to the classical evolution as occupation number is increased. We find that systems most similar to scalar field dark matter exhibit a logarithmic enhancement in the quantum breaktime with total occupation number. Systems with contact interactions or with field number state initial conditions, and linear dispersions, exhibit a power law enhancement. Finally, we find that the breaktime scaling depends on both model interactions and initial conditions.
Ort, förlag, år, upplaga, sidor
American Physical Society (APS) , 2022. Vol. 105, nr 3, artikel-id 036012
Nationell ämneskategori
Den kondenserade materiens fysik
Identifikatorer
URN: urn:nbn:se:kth:diva-310213DOI: 10.1103/PhysRevD.105.036012ISI: 000761170800003Scopus ID: 2-s2.0-85126015434OAI: oai:DiVA.org:kth-310213DiVA, id: diva2:1647298
Anmärkning
QC 20220325
2022-03-252022-03-252022-06-25Bibliografiskt granskad