Analysis of a simple equation for the ground state energy of the Bose gas
Eric Carlen, Ian Jauslin, Elliott H. Lieb
2019
Abstract
In 1963 a partial differential equation with a convolution nonlinearity was introduced in connection with a quantum mechanical manybody problem, namely the gas of bosonic particles. This equation is mathematically interesting for several reasons. (1) Although the equation was expected to be valid only for small values of the parameters, further investigation showed that predictions based on the equation agree well over the entire range of parameters with what is expected to be true for the solution of the true manybody problem. (2) The novel nonlinearity is easy to state but seems to have almost no literature up to now. (3) The earlier work did not prove existence and uniqueness of a solution, which we provide here along with properties of the solution such as decay at infinity.
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 tarball: 19cjl1.0.1.tar.gz
 git repository: 19cjlgit (the git repository contains detailed information about the changes in the paper as well as the source code for all previous versions).
Other releases
 arXiv preprint: arXiv:1912.04987.
 This article was peer reviewed for: Pure and Applied Analysis, Volume 2, Issue 3, pages 659684, 2020.
Numerical computations
The numerical computations in this paper were carried out using an early version of simplesolv. Note that this early version is not compatible with the version of simplesolv published on this website. The code is included with the LaTeX source, in the 'figs' directory.
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This work has been presented at the following conferences:

[Wa24]: Nonperturbative behavior of interacting Bosons at intermediate densities
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[SMM125]: Nonperturbative behavior of interacting Bosons at intermediate densities
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[CMT23]: Nonperturbative behavior of interacting Bosons at intermediate densities
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[TXST23]: BoseEinstein condensation and the Simplified Approach to interacting Bosons
Texas State University, San Marcos, Texas, USA, Jul 24 2023

[Da23]: Nonperturbative behavior of interacting Bosons at intermediate densities
UC Davis, California, USA, May 30 2023
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[Pr23]: Nonperturbative behavior of interacting Bosons at intermediate densities
Princeton University, New Jersey, USA, Apr 18 2023
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[SISSA23]: Interacting Bosons at intermediate densities
SISSA, Trieste, Italy, Mar 16 2023
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[Ru23]: Interacting Bosons at intermediate densities
Rutgers University, New Brunswick, New Jersey, USA, Mar 09 2023
pdf 
[Ga22]: An effective equation to study Bose gases at all densities
Advances in Classical, Quantum and Statistical Mechanics  A celebration of the work and contributions of Giovanni Gallavotti  On the occasion of his 80th birthday, Rome, Italy, May 13 2022
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[Mi22]: An effective equation to study Bose gases at all densities
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[Tu22]: An effective equation to study Bose gases at all densities
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[LMU21]: An effective equation to study Bose gases at all densities
Ludwig Maximilian University, Munich, Germany, Apr 28 2021
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[Ye21]: An effective equation to study Bose gases at all densities
Yeshiva University, New York, NY, USA, Apr 07 2021
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[Ja21]: An effective equation to study Bose gases at all densities
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[Pe21]: An effective equation to study Bose gases at all densities
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[MC21]: Many interacting quantum particles: open problems, and a new point of view on an old problem
Mathematical Conversations, Institute for Advanced Study, Princeton, NJ, USA, Mar 10 2021
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[Cop21]: An effective equation to study Bose gasses at all densities
University of Copenhagen, Denmark, Jan 13 2021
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[Rut20]: Analysis of a nonlinear, nonlocal PDE to study Bose gases at all densities
Rutgers University, New Brunswick, New Jersey, USA, Dec 16 2020
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[TAMU20b]: A new approach to the Mathematics of the Bose gas
Texas A&M, College Station, Texas, USA, Nov 30 2020
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[SIAM20]: An Effective Equation To Study Bose Gasses At All Densities
SIAM TexasLouisiana Sectionnal Meeting, MiniSymposium on Spectral Theory and Mathematical Physics, online, Oct 17 2020
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[IAMP20]: An effective equation to study Bose gasses at all densities
International Association of Mathematical of Mathematical Physics, One World Seminars, online, Sep 22 2020
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[TAMU20]: A simple equation to study interacting Bose gasses
Texas A&M, College Station, Texas, USA, May 15 2020
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[HaRM20]: A simplified approach to interacting Bose gases
Harvard University, Cambridge, Massachusetts, USA, Apr 01 2020
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[To20]: A simplified approach to interacting Bose gases
University of Toronto, Ontario, Canada, Mar 06 2020
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[Pr20]: A simplified approach to interacting Bose gases
Princeton University, New Jersey, USA, Mar 03 2020
video, pdf 
[VATech20]: A simplified approach to interacting Bose gases
VirginiaTech, Blacksburg, Virginia, USA, Feb 14 2020
pdf 
[Davis20]: A simplified approach to interacting Bose gases
UC Davis, California, USA, Feb 06 2020
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[GaTech20]: A simplified approach to interacting Bose gases
GeorgiaTech, Atlanta, Georgia, USA, Jan 21 2020
pdf 
[UBC20]: A simplified approach to interacting Bose gases
University of British Columbia, Vancouver, British Columbia, Canada, Jan 09 2020
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[GLaMP19]: Lieb's simplified approach to interacting Bose gases
Great Lakes Mathematical Physics Meeting 2019, Oberlin, Ohio, USA, Jun 29 2019
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