---
_id: '8044'
abstract:
- lang: eng
  text: Many questions concerning models in quantum mechanics require a detailed analysis
    of the spectrum of the corresponding Hamiltonian, a linear operator on a suitable
    Hilbert space. Of particular relevance for an understanding of the low-temperature
    properties of a system is the structure of the excitation spectrum, which is the
    part of the spectrum close to the spectral bottom. We present recent progress
    on this question for bosonic many-body quantum systems with weak two-body interactions.
    Such system are currently of great interest, due to their experimental realization
    in ultra-cold atomic gases. We investigate the accuracy of the Bogoliubov approximations,
    which predicts that the low-energy spectrum is made up of sums of elementary excitations,
    with linear dispersion law at low momentum. The latter property is crucial for
    the superfluid behavior the system.
article_processing_charge: No
author:
- first_name: Robert
  full_name: Seiringer, Robert
  id: 4AFD0470-F248-11E8-B48F-1D18A9856A87
  last_name: Seiringer
  orcid: 0000-0002-6781-0521
citation:
  ama: 'Seiringer R. Structure of the excitation spectrum for many-body quantum systems.
    In: <i>Proceeding of the International Congress of Mathematicans</i>. Vol 3. International
    Congress of Mathematicians; 2014:1175-1194.'
  apa: 'Seiringer, R. (2014). Structure of the excitation spectrum for many-body quantum
    systems. In <i>Proceeding of the International Congress of Mathematicans</i> (Vol.
    3, pp. 1175–1194). Seoul, South Korea: International Congress of Mathematicians.'
  chicago: Seiringer, Robert. “Structure of the Excitation Spectrum for Many-Body
    Quantum Systems.” In <i>Proceeding of the International Congress of Mathematicans</i>,
    3:1175–94. International Congress of Mathematicians, 2014.
  ieee: R. Seiringer, “Structure of the excitation spectrum for many-body quantum
    systems,” in <i>Proceeding of the International Congress of Mathematicans</i>,
    Seoul, South Korea, 2014, vol. 3, pp. 1175–1194.
  ista: 'Seiringer R. 2014. Structure of the excitation spectrum for many-body quantum
    systems. Proceeding of the International Congress of Mathematicans. ICM: International
    Congress of Mathematicans vol. 3, 1175–1194.'
  mla: Seiringer, Robert. “Structure of the Excitation Spectrum for Many-Body Quantum
    Systems.” <i>Proceeding of the International Congress of Mathematicans</i>, vol.
    3, International Congress of Mathematicians, 2014, pp. 1175–94.
  short: R. Seiringer, in:, Proceeding of the International Congress of Mathematicans,
    International Congress of Mathematicians, 2014, pp. 1175–1194.
conference:
  end_date: 2014-08-21
  location: Seoul, South Korea
  name: 'ICM: International Congress of Mathematicans'
  start_date: 2014-08-13
date_created: 2020-06-29T07:59:35Z
date_published: 2014-08-01T00:00:00Z
date_updated: 2023-10-17T11:12:33Z
day: '01'
department:
- _id: RoSe
intvolume: '         3'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: http://www.icm2014.org/en/vod/proceedings.html
month: '08'
oa: 1
oa_version: Published Version
page: 1175-1194
publication: Proceeding of the International Congress of Mathematicans
publication_identifier:
  isbn:
  - '9788961058063'
publication_status: published
publisher: International Congress of Mathematicians
quality_controlled: '1'
scopus_import: '1'
status: public
title: Structure of the excitation spectrum for many-body quantum systems
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 3
year: '2014'
...