Collective Variable Approach to Many-Boson Systems at High Density
スポンサーリンク
概要
- 論文の詳細を見る
Green's functions of phonons for many-boson systems at high density are obtained form the phonon Hamiltonian given in a previous paper on the basis of the coherent-state representation. A dispersion equation derived from these Green's functions gives rise to the excitation spectrum leading to the Feynman energy in the low-momentum limit. It is shown that the dynamic structure function obtained here satisfies the sum rules in the low-momentum limit. As an illustrative example, the one-dimensional Lieb-Liniger model is considered. The relationships to the previous theories, in particular, to the velocity field approach of Yamasaki, Kebukawa and Sunakawa and to our density and phase operator approach are elucidated by the use of a unitary transformation. Discussion will be made on the D-wave portion of the roton-roton interaction in relation to the resonance state of roton pair studied in one of our previous papers. Finally, it is pointed out that the zeroth Fourier transform of the phase operator is related to the superfluid velocity in the two-fluid theory of liquid helium II.
- 理論物理学刊行会の論文
- 1977-02-25
著者
-
Nishiyama Toshiyuki
Department Of Physics College Of General Education Osaka University
-
Nishiyama Toshiyuki
Department Of Physics Colleg Of General Education Osaka University
-
TSUJII Masakazu
Departmento of Physics, College of General Education Osaka University
-
Tsujii Masakazu
Department Of Physics College Of General Education Osaka University
-
NISHIYAMA Toshiyuki
Department of Physics, Colleg of General Education, Osaka University
-
NISHIYAMA Toshiyuki
Department of Physics and Applied Mathematics Osaka Institute of Technology
関連論文
- Inelastic Scattering of Negative Pions on C^ under Distorted Wave Impulse Approximation
- The Concave Nature of the Energy Spectrum of Liquid _4He at Very Low-Wave Numbers
- Pair Theory for Individual Particles in Liquid Helium II
- Momentum Distribution and Ground-State Energy of Liquid ^4He at the Absolute Zero Temperature
- Use of a Coherent-State Representation for a Many-Boson System at High Density
- A Long-Range Attractive Interaction of Rotons in Superfluid ^4He
- Line Width of Rotons in HeII for Wave Numbers between 2A^ and 3A^
- Collective Variable Approach to Many-Boson Systems at High Density
- Momentum Distribution of a Charged Bose Gas at High Density
- On Collective and Internal Motions in a Bose System
- An Algebraic Theory of the Density Matrix, II
- Electrostatic Interactions in an Electron-Ion Gas at High Density
- Momentum Distribution of an Interacting Many-Boson System at High Density
- Condensate Fraction of a Charged Bose Gas at High Density : Condensed Matter and Statistical Physics
- An Algebraic Theory of the Density Matrix, I
- Coherent State Approach to Many-Boson Problems : Ground-State Energy
- Equivalent Hamiltonian of an Electron Gas at High Density
- State Vectors in the Collective Description
- Theory of Sound Waves and collective Description
- Dispersion Equation and Level Density of Rotons in Liquid He II
- Microscopic Theory of the Energy Spectrum of Liquid Helium
- Method of Collective Description of the Excitations in Liquid Helium
- Momentum Distribution of an Interacting Many-Boson System
- Ground-State Energy of a Many-Boson System : Density and Phase Operator Approach
- Note On Many Fermion Problems
- A Quantum Theory of Boson Assemblies, II : A Classical Approach to Many-Boson Problems