---
_id: '7790'
abstract:
- lang: eng
  text: "We prove a lower bound for the free energy (per unit volume) of the two-dimensional
    Bose gas in the thermodynamic limit. We show that the free energy at density \U0001D70C
    and inverse temperature \U0001D6FD differs from the one of the noninteracting
    system by the correction term \U0001D70B\U0001D70C\U0001D70C\U0001D6FD\U0001D6FD
    . Here, is the scattering length of the interaction potential, and \U0001D6FD
    is the inverse Berezinskii–Kosterlitz–Thouless critical temperature for superfluidity.
    The result is valid in the dilute limit \U0001D70C and if \U0001D6FD\U0001D70C
    ."
article_number: e20
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Andreas
  full_name: Deuchert, Andreas
  id: 4DA65CD0-F248-11E8-B48F-1D18A9856A87
  last_name: Deuchert
  orcid: 0000-0003-3146-6746
- first_name: Simon
  full_name: Mayer, Simon
  id: 30C4630A-F248-11E8-B48F-1D18A9856A87
  last_name: Mayer
- first_name: Robert
  full_name: Seiringer, Robert
  id: 4AFD0470-F248-11E8-B48F-1D18A9856A87
  last_name: Seiringer
  orcid: 0000-0002-6781-0521
citation:
  ama: Deuchert A, Mayer S, Seiringer R. The free energy of the two-dimensional dilute
    Bose gas. I. Lower bound. <i>Forum of Mathematics, Sigma</i>. 2020;8. doi:<a href="https://doi.org/10.1017/fms.2020.17">10.1017/fms.2020.17</a>
  apa: Deuchert, A., Mayer, S., &#38; Seiringer, R. (2020). The free energy of the
    two-dimensional dilute Bose gas. I. Lower bound. <i>Forum of Mathematics, Sigma</i>.
    Cambridge University Press. <a href="https://doi.org/10.1017/fms.2020.17">https://doi.org/10.1017/fms.2020.17</a>
  chicago: Deuchert, Andreas, Simon Mayer, and Robert Seiringer. “The Free Energy
    of the Two-Dimensional Dilute Bose Gas. I. Lower Bound.” <i>Forum of Mathematics,
    Sigma</i>. Cambridge University Press, 2020. <a href="https://doi.org/10.1017/fms.2020.17">https://doi.org/10.1017/fms.2020.17</a>.
  ieee: A. Deuchert, S. Mayer, and R. Seiringer, “The free energy of the two-dimensional
    dilute Bose gas. I. Lower bound,” <i>Forum of Mathematics, Sigma</i>, vol. 8.
    Cambridge University Press, 2020.
  ista: Deuchert A, Mayer S, Seiringer R. 2020. The free energy of the two-dimensional
    dilute Bose gas. I. Lower bound. Forum of Mathematics, Sigma. 8, e20.
  mla: Deuchert, Andreas, et al. “The Free Energy of the Two-Dimensional Dilute Bose
    Gas. I. Lower Bound.” <i>Forum of Mathematics, Sigma</i>, vol. 8, e20, Cambridge
    University Press, 2020, doi:<a href="https://doi.org/10.1017/fms.2020.17">10.1017/fms.2020.17</a>.
  short: A. Deuchert, S. Mayer, R. Seiringer, Forum of Mathematics, Sigma 8 (2020).
corr_author: '1'
date_created: 2020-05-03T22:00:48Z
date_published: 2020-03-14T00:00:00Z
date_updated: 2026-04-03T09:30:21Z
day: '14'
ddc:
- '510'
department:
- _id: RoSe
doi: 10.1017/fms.2020.17
ec_funded: 1
external_id:
  arxiv:
  - '1910.03372'
  isi:
  - '000527342000001'
file:
- access_level: open_access
  checksum: 8a64da99d107686997876d7cad8cfe1e
  content_type: application/pdf
  creator: dernst
  date_created: 2020-05-04T12:02:41Z
  date_updated: 2020-07-14T12:48:03Z
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  file_name: 2020_ForumMath_Deuchert.pdf
  file_size: 692530
  relation: main_file
file_date_updated: 2020-07-14T12:48:03Z
has_accepted_license: '1'
intvolume: '         8'
isi: 1
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '03'
oa: 1
oa_version: Published Version
project:
- _id: 25C6DC12-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '694227'
  name: Analysis of quantum many-body systems
publication: Forum of Mathematics, Sigma
publication_identifier:
  eissn:
  - 2050-5094
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
related_material:
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    relation: earlier_version
    status: public
scopus_import: '1'
status: public
title: The free energy of the two-dimensional dilute Bose gas. I. Lower bound
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
volume: 8
year: '2020'
...