Strongly-correlated fermionic matter in the dilute limit

Title: Strongly-correlated fermionic matter in the dilute limit

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Abstract

We study 'the ground-state properties of the many-body system composed of spin-l/2 fermions interacting via a zero-range, infinite scattering length contact interaction.' Sometimes referred to as the George Bertsch problem, it is of particular interest in astrophysics in connection with the equation of state for neutron matter and has been revisited recently with the advent of experimental studies of the BCS to BEC crossover in ultracold fermionic atom gases. We will show that new insights into the solution to this problem are obtained in the context of a coupled-cluster (exp S) expansion approach to calculating the equation of state for dilute fermionic systems and that present state-of-the-art Monte Carlo calculations have not yet provided the definitive answer.

Authors:

Mihaila, Bogdan ^[1]; Cardenas, Andres L ^[1]

Los Alamos National Laboratory

Publication Date:: 2008-01-01

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 960767

Report Number(s):: LA-UR-08-07128; LA-UR-08-7128
TRN: US201008%%687

DOE Contract Number:: AC52-06NA25396

Resource Type:: Journal Article

Country of Publication:: United States

Language:: English

Subject:: 36; ASTROPHYSICS; ATOMS; BOSE-EINSTEIN CONDENSATION; CALCULATION METHODS; COOPER PAIRS; EQUATIONS; FERMIONS; FERMI GAS; GROUND STATES; MANY-BODY PROBLEM; MATHEMATICAL SOLUTIONS; MATTER; MOLECULES; NUCLEAR MATTER; SCATTERING LENGTHS

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                    Mihaila, Bogdan, and Cardenas, Andres L. Strongly-correlated fermionic matter in the dilute limit.  United States: N. p., 2008. 
        Web.

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                    Mihaila, Bogdan, & Cardenas, Andres L. Strongly-correlated fermionic matter in the dilute limit.  United States.

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                    Mihaila, Bogdan, and Cardenas, Andres L. Tue .  
        "Strongly-correlated fermionic matter in the dilute limit".  United States.  https://www.osti.gov/servlets/purl/960767.

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@article{osti_960767,

  title        = {Strongly-correlated fermionic matter in the dilute limit},

  author       = {Mihaila, Bogdan and Cardenas, Andres L},

  abstractNote = {We study 'the ground-state properties of the many-body system composed of spin-l/2 fermions interacting via a zero-range, infinite scattering length contact interaction.' Sometimes referred to as the George Bertsch problem, it is of particular interest in astrophysics in connection with the equation of state for neutron matter and has been revisited recently with the advent of experimental studies of the BCS to BEC crossover in ultracold fermionic atom gases. We will show that new insights into the solution to this problem are obtained in the context of a coupled-cluster (exp S) expansion approach to calculating the equation of state for dilute fermionic systems and that present state-of-the-art Monte Carlo calculations have not yet provided the definitive answer.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/960767},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2008},

  month        = {1}

}

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