60 research outputs found
The Information Geometry of the Ising Model on Planar Random Graphs
It has been suggested that an information geometric view of statistical
mechanics in which a metric is introduced onto the space of parameters provides
an interesting alternative characterisation of the phase structure,
particularly in the case where there are two such parameters -- such as the
Ising model with inverse temperature and external field .
In various two parameter calculable models the scalar curvature of
the information metric has been found to diverge at the phase transition point
and a plausible scaling relation postulated: . For spin models the necessity of calculating in
non-zero field has limited analytic consideration to 1D, mean-field and Bethe
lattice Ising models. In this letter we use the solution in field of the Ising
model on an ensemble of planar random graphs (where ) to evaluate the scaling behaviour of the scalar curvature, and find
. The apparent discrepancy is traced
back to the effect of a negative .Comment: Version accepted for publication in PRE, revtex
Information measures based on Tsallis' entropy and geometric considerations for thermodynamic systems
An analysis of the thermodynamic behavior of quantum systems can be performed
from a geometrical perspective investigating the structure of the state space.
We have developed such an analysis for nonextensive thermostatistical
frameworks, making use of the q-divergence derived from Tsallis' entropy.
Generalized expressions for operator variance and covariance are considered, in
terms of which the fundamental tensor is given.Comment: contribution to 3rd NEXT-SigmaPhi International Conference (August
2005, Kolymbari, Greece
Thermodynamic Geometry of black hole in the deformed Horava-Lifshitz gravity
We investigate the thermodynamic geometry and phase transition of
Kehagias-Sfetsos black hole in the deformed Horava-Lifshitz gravity with
coupling constant . The phase transition in black hole
thermodynamics is thought to be associated with the divergence of the
capacities. And the structures of these divergent points are studied. We also
find that the thermodynamic curvature produced by the Ruppeiner metric is
positive definite for all and is divergence at
corresponded to the divergent points of and . These results
suggest that the microstructure of the black hole has an effective repulsive
interaction, which is very similar to the ideal gas of fermions. These may
shine some light on the microstructure of the black hole.Comment: 5 pages, 3 figure
Zmiennosc morfologiczna Carex spicata Huds. w wybranych typach zbiorowisk roslinnych
This paper presents the results of the study on the morphological variability of the
populations of Carex spicata Huds., growing in different types of plant communities. The three
morphotypes of C. spicata were determinated. The connections between the occurrence of the
morphotypes and the type of plant community were proved
Roslinnosc rezerwatu przyrody Dlugogory
The natural reserve “Długogóry”, situated near the town of Myslibórz in southern part
of the western Pomeranian region, is a valuable element of the system of protected areas in Poland.
The reserve covers the area of 120.36 ha. The main protected objects are: typical landscape
of glacial moraine, with many small hills and many wetlands situated in local depressions between
the hills; large amount of erratic stones, covered by rich moss and lichen communities; well
preserved fertile beech forest with rare species of plants
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