非相对论弱相互作用玻色气体的有效场理论处理

采用有效场理论研究了非相对论弱相互作用玻色-爱因斯坦凝聚量子气体的一般性质.在分析了系统的不可重整化性质后,从有效拉氏量出发,计算了最低阶环路修正下拉氏量参量的运动耦合常数(running coupling constant)的形式,并且得到了相应的微分方程.研究结果表明,不同于相对论玻色气体的有效理论,对非相对论弱相互作用的玻色气体,可以移除该有效理论中的内禀能量尺度,即可令该有效理论的内禀能量尺度取无穷大值.所得的分析结果将有助于对玻色-爱因斯坦凝聚的临界性质和行为的深入研究.

Effective field theory approach to the weakly interacting bose gas

In this paper we study the theory of nonrelativistic weakly interacting Bose gas from the point of view of effective field theory. Firstly, the nonrenormalizability of the theory is briefly discussed. Then, starting from the effective Lagrangian, the lowest order contributions of Feynman diagrams are calculated for the parameters in the effective Lagrangian. These illustrate the running coupling constant phenomenon. After that, the differential align of the parameters in the effective Lagrangian is obtained. We show that the intrinsic energy scale of this effective theory can be removed, while it is not possible to do so for relativistic Bose gas. Our results can help to study the critical behavior of weakly interacting Bose gas.