https://doi.org/10.1051/epjconf/202022601005
Renormalization Group in Non-Relativistic Quantum Statistics
1
Department of Military Technology, National Defence University,
Santahaminantie 2,
00860
Helsinki,
Finland
2
Department of Theoretical Physics, Faculty of Physics, Saint Petersburg State University,
Ul’yanovskaya 1, Petrodvorets,
198504
Saint Petersburg,
Russia
★ e-mail: juha.honkonen@helsinki.fi
Published online: 20 January 2020
Dynamic behaviour of a boson gas near the condensation transition in the symmetric phase is analyzed with the use of an effective large-scale model derived from time-dependent Green functions at finite temperature. A renormalization-group analysis shows that the scaling exponents of critical dynamics of the effective multi-charge model coincide with those of the standard model A. The departure of this result from the description of the superfluid transition by either model E or F of the standard phenomenological stochastic models is corroborated by the analysis of a generalization of model F, which takes into account the effect of compressible fluid velocity. It is also shown that, contrary to the single-charge model A, there are several correction exponents in the effective model, which are calculated at the leading order of the ɛ= 4 − d expansion.
© The Authors, published by EDP Sciences, 2020
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