Using the renormalization group method, the critical behavior of Gaussian model is studied in external magnetic fields on X fractal lattices embedded in two-dimensional and -dimensional Euclidean spaces, respectively...Using the renormalization group method, the critical behavior of Gaussian model is studied in external magnetic fields on X fractal lattices embedded in two-dimensional and -dimensional Euclidean spaces, respectively. Critical points and exponents are calculated. It is found that there is long-range order at finite temperature for this model, and that the critical points do not change with the space dimensionality (or the fractal dimensionality ). It is also found that the critical exponents are very different from results of Ising model on the same lattices, and that the exponents on X lattices are different from the exact results on translationally symmetric lattices.展开更多
Thermodynamics of phase transition for a black hole in 5D Einstein-Gauss-Bonnet gravity with a negative cosmological constant is studied.As the Bekenstein-Hawking entropy is adopted,we find the heat capacity,volume ex...Thermodynamics of phase transition for a black hole in 5D Einstein-Gauss-Bonnet gravity with a negative cosmological constant is studied.As the Bekenstein-Hawking entropy is adopted,we find the heat capacity,volume expansion coefficient and isothermal compressibility are divergent at the critical points,which implies the existence of phase transitions.The fact that the phase transitions are indeed second order is revealed by studying the Ehrenfest's equations and the Prigogine-Defay ratio.Furthermore near the critical points,we also explicitly calculate the critical exponents of the relevant thermodynamic quantities at fixed charge or fixed temperature.It is shown that the corresponding critical exponents satisfy the thermodynamic scaling law.The Generalized Homogeneous Function hypothesis is also checked by studying the Helmholtz free energy,which is shown to be consistent with the thermodynamic scaling law.展开更多
In this paper, we use the modified Hod's treatment and the Kunstatter's method to study the horizon area spectrum and entropy spectrum in Gauss-Bonnet de-Sitter space-time, which is regarded as the natural gen...In this paper, we use the modified Hod's treatment and the Kunstatter's method to study the horizon area spectrum and entropy spectrum in Gauss-Bonnet de-Sitter space-time, which is regarded as the natural generalization of Einstein gravity by including higher derivative correction terms to the original Einstein-Hilbert action. The horizon areas have some properties that are very different from the vacuum solutions obtained from the frame of Einstein gravity. With the new physical interpretation of quasinormal modes, the area/entropy spectrum for the event horizon for nearextremal Gauss-Bonnet de Sitter black holes are obtained. Meanwhile, we also extend the discussion of area/entropy quantization to the non-extremal black holes solutions.展开更多
Considering in symmetrical half-length bond operations,we present in this paper two types of newlydeveloped generalizations of the remarkable Migdal-Kadanoff bond-moving renormalization group transformation recursion ...Considering in symmetrical half-length bond operations,we present in this paper two types of newlydeveloped generalizations of the remarkable Migdal-Kadanoff bond-moving renormalization group transformation recursion procedures.The predominance in application of these generalized procedures are illustrated by making use of them to study the critical behavior of the spin-continuous Gaussian model constructed on the typical translational invariant lattices and fractals respectively.Results such as the correlation length critical exponents obtained by these means are found to be in good conformity with the classical results from other previous studies.展开更多
文摘Using the renormalization group method, the critical behavior of Gaussian model is studied in external magnetic fields on X fractal lattices embedded in two-dimensional and -dimensional Euclidean spaces, respectively. Critical points and exponents are calculated. It is found that there is long-range order at finite temperature for this model, and that the critical points do not change with the space dimensionality (or the fractal dimensionality ). It is also found that the critical exponents are very different from results of Ising model on the same lattices, and that the exponents on X lattices are different from the exact results on translationally symmetric lattices.
基金supported by the National Natural Science Foundation of China (Grant Nos.11147012 and 11263003)supported by the Research Funds of Hubei University for Nationalities (Grant No.MY2012B007)the Natural Science Fund of Education Department of Hubei Province (Grant No.Q20131901)
文摘Thermodynamics of phase transition for a black hole in 5D Einstein-Gauss-Bonnet gravity with a negative cosmological constant is studied.As the Bekenstein-Hawking entropy is adopted,we find the heat capacity,volume expansion coefficient and isothermal compressibility are divergent at the critical points,which implies the existence of phase transitions.The fact that the phase transitions are indeed second order is revealed by studying the Ehrenfest's equations and the Prigogine-Defay ratio.Furthermore near the critical points,we also explicitly calculate the critical exponents of the relevant thermodynamic quantities at fixed charge or fixed temperature.It is shown that the corresponding critical exponents satisfy the thermodynamic scaling law.The Generalized Homogeneous Function hypothesis is also checked by studying the Helmholtz free energy,which is shown to be consistent with the thermodynamic scaling law.
基金Supported by the Natural Science Foundation of China under Grant No.10275030Cuiying Project of Lanzhou University 225000-582404
文摘In this paper, we use the modified Hod's treatment and the Kunstatter's method to study the horizon area spectrum and entropy spectrum in Gauss-Bonnet de-Sitter space-time, which is regarded as the natural generalization of Einstein gravity by including higher derivative correction terms to the original Einstein-Hilbert action. The horizon areas have some properties that are very different from the vacuum solutions obtained from the frame of Einstein gravity. With the new physical interpretation of quasinormal modes, the area/entropy spectrum for the event horizon for nearextremal Gauss-Bonnet de Sitter black holes are obtained. Meanwhile, we also extend the discussion of area/entropy quantization to the non-extremal black holes solutions.
基金Supported by the Shandong Province Science Foundation for Youths under Grant No.ZR2011AQ016the Shandong Province Postdoctoral Innovation Program Foundation under Grant No.201002015+1 种基金the Scientific Research Starting Foundation,Youth Foundation under Grant No.XJ201009the Foundation of Scientific Research Training Plan for Undergraduate Students under Grant No.2010A023 of Qufu Normal University
文摘Considering in symmetrical half-length bond operations,we present in this paper two types of newlydeveloped generalizations of the remarkable Migdal-Kadanoff bond-moving renormalization group transformation recursion procedures.The predominance in application of these generalized procedures are illustrated by making use of them to study the critical behavior of the spin-continuous Gaussian model constructed on the typical translational invariant lattices and fractals respectively.Results such as the correlation length critical exponents obtained by these means are found to be in good conformity with the classical results from other previous studies.