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Qiuping A. Wang

Publications and source records attributed to Qiuping A. Wang.

At least 55 records · Page 3Linked to original sources

About "On certain incomplete statistics" by Lima et al

Lima et al recently claim that ({\em Chaos, Solitons $&$ Fractals,} 2004;19:1005)the entropy for the incomplete statistics based on the normalization$\sum_ip_i^q=1$ should be $S=-\sum_ip_i^{2q-1}\ln_qp_i$ instead of$S=-\sum_ip_i^{q}\ln_qp_i$ initially proposed by Wang. We indicate here that thisconclusion is a result of erroneous use of temperature definition for the incompletestatistics.

cond-mat.stat-mech↗

Nonextensive thermostatistics for heterogeneous systems containing different $q$'s

The nonextensive statistics based on Tsallis entropy have been so far used for the systems composed of subsystems having same $q$. The applicability of this statistics to the systems with different $q$'s is still a matter of investigation. The actual difficulty is that the class of systems to which the theory has been applied is limited by the usual nonadditivity rule of Tsallis entropy which, in reality, has been established for the systems having same $q$ value. In this paper, we propose a more general nonadditivity rule for Tsallis entropy. This rule, as the usual one for same $q$-systems, can be proved to lead uniquely to Tsallis entropy in the context of systems containing different $q$-subsystems. A zeroth law of thermodynamics is established between different $q$-systems on the basis of this new nonadditivity.

cond-mat.stat-mech↗

From complexity to incompleteness of treatable information

The necessary information for specifying a complex system may not be completely accessible to us, i.e., to mathematical treatments. This is not to be confounded with the incompleteness of our knowledge about whatever systems or nature, since here information is our ignorance. In conventional statistics and information theories, this information or ignorance is supposed completely accessible to theoretical treatments connected with complete probability distributions. However, the hypothesis of incomplete information supposes that the information of certain systems can be incomplete as calculated in the usual way as in the conventional information theories. This hypothesis has been used in order to generalize the conventional statistics theory. The generalized statistics and information theory characterized by an empirical parameter has been proved useful for the formulation of the nonextensive statistical mechanics based on Tsallis entropy, for the description of some correlated quantum systems and for the derivation of the stationary probability distributions of nonequilibrium complex systems evolving in hierarchical or fractal phase space. In this paper, the incompleteness of the information will be discussed from mathematical, physical and epistemological considerations with an example of information calculation in fractal phase space with stationary probability distribution.

cond-mat.stat-mech↗

Fractional exclusion statistics with incomplete information

We introduce the hypothesis of incomplete information into the fractional exclusion statistics in order to apply the latter to some correlated heavy fermion systems. It is shown that the actual inexplicit distribution function of FES may be replaced by an equivalent explicit one of which the form does not change with $α$ value.

cond-mat.stat-mech↗

Temperature and pressure in nonextensive thermostatistics

The definitions of the temperature in the nonextensive statistical thermodynamics based on Tsallis entropy are analyzed. A definition of pressure is proposed for nonadditive systems by using a nonadditive effective volume. The thermodynamics of nonadditive photon gas is discussed on this basis. We show that the Stefan-Boltzmann law can be preserved within nonextensive thermodynamics.

physics.data-an↗

Power law distribution of Rényi entropy for equilibrium systems having nonadditive energy

Using Rényi entropy, a possible thermostatistics for nonextensive systems is discussed. We show that it is possible to get the $q$-exponential distribution function for nonextensive systems having nonadditive energy but additive entropy. It is also shown that additive energy, as a approximation within nonextensive statistics, is not suitable for discussing fundamental problems for interacting systems.

cond-mat.stat-mech↗

Incomplete information and fractal phase space

The incomplete statistics for complex systems is characterized by a so called incompleteness parameter $ω$ which equals unity when information is completely accessible to our treatment. This paper is devoted to the discussion of the incompleteness of accessible information and of the physical signification of $ω$ on the basis of fractal phase space. $ω$ is shown to be proportional to the fractal dimension of the phase space and can be linked to the phase volume expansion and information growth during the scale refining process.

cond-mat.stat-mech↗

About an alternative distribution function for fractional exclusion statistics

We show that it is possible to replace the actual implicit distribution function of the fractional exclusion statistics by an explicit one whose form does not change with the parameter $α$. This alternative simpler distribution function given by a generalization of Pauli exclusion principle from the level of the maximal occupation number is not completely equivalent to the distributions obtained from the level of state number counting of the fractional exclusion particles. Our result shows that the two distributions are equivalent for weakly bosonized fermions ($α>>0$) at not very high temperatures.

cond-mat.stat-mech↗

Extensive generalization of statistical mechanics based on incomplete information theory

Statistical mechanics is generalized on the basis of an additive information theory for incomplete probability distributions. The incomplete normalization $\sum_{i=1}^wp_i^q=1$ is used to obtain generalized entropy $S=-k\sum_{i=1}^wp_i^q\ln p_i$. The concomitant incomplete statistical mechanics is applied to some physical systems in order to show the effect of the incompleteness of information. It is shown that this extensive generalized statistics can be useful for the correlated electron systems in weak coupling regime.

cond-mat.stat-mech↗

Correlated electrons and generalized statistics

Several important generalizations of Fermi-Dirac distribution are compared to numerical and experimental results for correlated electron systems. It is found that the quantum distributions based on incomplete information hypothesis can be useful for describing this kind of systems. We show that the additive incomplete fermion distribution gives very good description of weakly correlated electrons and that the nonadditive one is suitable to very strong correlated cases.

cond-mat.stat-mech↗

On the generalized entropy pseudoadditivity for complex systems

We show that Abe's general pseudoadditivity for entropy prescribed by thermal equilibrium in nonextensive systems holds not only for entropy, but also for energy. The application of this general pseudoadditivity to Tsallis entropy tells us that the factorization of the probability of a composite system into product of the probabilities of the subsystems is just a consequence of the existence of thermal equilibrium and not due to the independence of the subsystems.

cond-mat.stat-mech↗

Extensive form of equilibrium nonextensive statistics

It is argued that the factorization of compound probability over subsystems is a consequence of the existence of thermodynamic equilibrium in the composite system having Tsallis entropy. So it should be respected by all exact calculations concerning interacting nonextensive subsystems. Using nonextensive energy satisfying the factorization, we propose an additive formalism of nonextensive statistical mechanics with additive q-deformed physical quantities and exponential distributions. This formalism leads to exact quantum gas distributions different from those given by factorization approximation. The fermion distribution of present work shows similar behaviors to that of strongly correlated electrons.

cond-mat.stat-mech↗

Incomplete information and correlated electrons

Although Gödel's incompleteness theorem made mathematician recognize that no axiomatic system could completely prove its correctness and that there is an eternal hole between our knowledge and the world, physicists so far continue to work on the approaches based on the hypothesis to completely or approximately know the systems of interest. In this paper, however, I review the recent development of a different approach, a statistical theory based upon the notion of incomplete information. This consideration leads to generalized statistical mechanics characterized by an incompleteness parameter which equals unity when information is complete. The mathematical and physical bases of the information incompleteness are discussed. The application of the concomitant incomplete quantum distribution to correlated electron systems is reviewed.

cond-mat.stat-mech↗

Many-body q-exponential distribution prescribed by factorization hypothesis

The factorization problem of $q$-exponential distribution within nonextensive statistical mechanics is discussed on the basis of Abe's general pseudoadditivity for equilibrium systems. it is argued that the factorization of compound probability into product of the probabilities of subsystems is nothing but the consequence of existence of thermodynamic equilibrium in the interacting systems having Tsallis entropy. So the factorization does not needs independent noninteracting systems and should be respected in all exact calculations concerning interacting nonextensive subsystems. This consideration makes it legitimate to use $q$-exponential distribution either for composite system or for single body in many-body systems. Some known results of ideal gases obtained with additive energy are reviewed.

cond-mat.stat-mech↗

Nonextensive statistics and incomplete information

We comment on some open questions and theoretical peculiarities in Tsallis nonextensive statistical mechanics. It is shown that the theoretical basis of the successful Tsallis' generalized exponential distribution shows some worrying properties with the conventional normalization and the escort probability. These theoretical difficulties may be avoided by introducing an so called incomplete normalization allowing to deduce Tsallis' generalized distribution in a more convincing and consistent way.

cond-mat.stat-mech↗

Quantum gas distributions prescribed by factorization hypothesis of probability

Nonextensive quantum gas distributions are investigated on the basis of the factorization hypothesis of compound probability required by thermodynamic equilibrium. It is shown that the formalisms of Tsallis nonextensive statistical mechanics with normalized average give distribution functions for standard bosons and fermions obeying Pauli principle. The formalism with unnormalized average leads to a intermediate quantum distribution comparable to that of fractional exclusion statistics, with Fermi surface at T=0 depending on the parameter $q$.

cond-mat.stat-mech↗

Incomplete statistics and nonextensive generalization of statistical mechanics

Statistical mechanics is generalized on the basis of an information theory for inexact or incomplete probability distributions. A parameterized normalization is proposed and leads to a nonextensive entropy. The resulting incomplete statistical mechanics is proved to have the same theoretical characteristics as Tsallis one based on the conventional normalization.

cond-mat.stat-mech↗

Incomplete nonextensive statistics and zeroth law of thermodynamics

We show that the zeroth law of thermodynamics holds within an alternative version of nonextensive statistical mechanics based on {\it incomplete probability distribution}. The generalized zeroth law leads to a generalized definition of thermodynamic functions which are possible to be used for systems with important nonextensivity (nonadditivity) in energy, volume or other external variables.

cond-mat.stat-mech↗