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Static and dynamic finite-size effects near critical points are described by means of field-theoretic renormalization-group methods. Two types of physical quantities are discussed: (i) free energy and Binder cumulant of the phi4 model and of spin models on anisotropic lattices, (ii) thermal conductivity of confined 4He near the superfluid transition. For the systems (i), quantitative predictions are made on the violation of two-scale factor universality of finite-size scaling functions above and below Tc, and a kind of restricted universality is predicted [1]. For the system (ii), nonuniversal finite-size effects are predicted for the thermal conductivity of 4He at the pressure dependent lambda line [2]. The predictions (i) can be tested by Monte Carlo simulations for Ising models and XY models. The predictions (ii) are compared with experimental data at the superfluid transition [3]. [1] V. Dohm, J. Phys. A 39, L 259 (2006); and to be published. [2] M. Töpler and V. Dohm, to be published. [3] D. Murphy, E. Genio, G. Ahlers, and F.L.Y. Liu, Phys. Rev. Lett. 90, 025301 (2003). |
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