Asymptotically Improved Convergence of Optimized Perturbation Theory in the Bose-Einstein Condensation Problem

Details Asymptotically Improved Convergence of Optimized Perturbation Theory in the Bose-Einstein Condensation Problem Asymptotically Improved Convergence of Optimized Perturbation Theory in the Bose-Einstein Condensation Problem

2002-07-11

arxiv.org/abs/cond-mat/0207295v3

Phys.Rev. A68 (2003) 043615

Physics

Condensed Matter

Soft Condensed Matter

38 pages, 3 eps figures, Revtex4. Final version in press Phys. Rev. A

Scientific paper

10.1103/PhysRevA.68.043615

We investigate the convergence properties of optimized perturbation theory, or linear $\delta$ expansion (LDE), within the context of finite temperature phase transitions. Our results prove the reliability of these methods, recently employed in the determination of the critical temperature T_c for a system of weakly interacting homogeneous dilute Bose gas. We carry out the explicit LDE optimized calculations and also the infrared analysis of the relevant quantities involved in the determination of $T_c$ in the large-N limit, when the relevant effective static action describing the system is extended to O(N) symmetry. Then, using an efficient resummation method, we show how the LDE can exactly reproduce the known large-N result for $T_c$ already at the first non-trivial order. Next, we consider the finite N=2 case where, using similar resummation techniques, we improve the analytical results for the nonperturbative terms involved in the expression for the critical temperature allowing comparison with recent Monte Carlo estimates of them. To illustrate the method we have considered a simple geometric series showing how the procedure as a whole works consistently in a general case.

Affiliated with

Also associated with

No associations

Rating

Asymptotically Improved Convergence of Optimized Perturbation Theory in the Bose-Einstein Condensation Problem does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Asymptotically Improved Convergence of Optimized Perturbation Theory in the Bose-Einstein Condensation Problem, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Asymptotically Improved Convergence of Optimized Perturbation Theory in the Bose-Einstein Condensation Problem will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-185178