Non Extensive Thermostatistics' - PowerPoint PPT Presentation

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Non Extensive Thermostatistics'

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where q characterizes the extensivity of the statistics. ... Self gravitating systems in Astrophysics. [A. R. Plastino & A. Plastino, Phys. Lett. ... – PowerPoint PPT presentation

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Title: Non Extensive Thermostatistics'


1
  • Non Extensive Thermostatistics.
  • Motivation
  • Variety of physical systems where Boltzmann-Gibbs
    thermostatistics fail
  • Long range interactions.
  • Long range memory- Non markovian evolution.

2
B.G. Statistics - A reminder.
  • Entropy
  • Constraints
  • Maximize the objective
  • Yields distribution

3
Postulate C. Tsallis J. Stat. Phys. 52 p479
(1988)
  • Generalized entropy where q characterizes
    the extensivity of the statistics.
  • Note For q1 regular B.G. Statistics is
    recovered

4
Properties of Sq
Sq/k
q-1
q-0.5
q0
q0.5
  • Positivity
  • Concavity Sq is concave (convex) for qgt0
    (qlt0)
  • Generalized AdditivitySq is super (sub)
    additive for qlt1 (qgt1)

q1
q2
qoo
p
5
Generalized canonical ensemble
  • We demand that at equilibrium, Sq have an
    extremum under constraints.
  • We define a generalized average energy
  • Maximization Objective
  • Yields distribution

6
Connection with ThermodynamicsE.M.F. Curado
C. Tsallis J. Phys. A. 24 pL69 (1991)
  • Define
  • Legendre transform
  • Thermodynamic relations

7
Generalized Thermodynamic relationships
  • Thermo stability Heat capacityC. Tsallis
    Phys. Lett. A, 206 p389 (1995)
  • H theorem.A. M. Mariz Phys. Lett. A, 165 p366
    (1995)
  • Focker Plank Eq.

8
  • Problem
  • ?i not invariant under uniform translation of
    energy spectrum.
  • Non extensivity of Generalized EnergyUq(AB) ?
    Uq (A)Uq (B)
  • Solution
  • Normalization of Generalized Energy
  • Previous results modified but still valid.
  • C. Tsallis et al Physica A, 291 p534 (1998)

9
Applications
  • Heat capacity of Hydrogen Atom.L.S. Lucena et
    al, Phys. Rev. E, 51 p6247 (1995)
  • Self gravitating systems in Astrophysics.A. R.
    Plastino A. Plastino, Phys. Lett. A,193 p251
    (1991)
  • Cosmic background microwave radiation.C.
    Tsallis et al, Phys. Rev. E, 52 p1447 (1995)
  • Long range interaction systems. P. Jund et al,
    Phys. Rev. B, 52 p50 (1995)
  • Levy flights, systematic derivation.

10
Levy Flights
  • Albert Einstein 1905
  • Paul Levy 1937

Brownian motion
Levy distributions
11
Levy Flights
  • Albert Einstein 1905
  • one step distribution funct. central limit
    theorem
  • N step distribution funct.

Paul Levy 1937 Levy-Gnedenko
Levy distribution
C. Tsallis et al. PRL 75 p3589 (1995)
12
Summary
  • A generalized non extensive thermodynamics can be
    formulated using a generalized entropy Sq.
  • Many mathematical characteristics of B.G.
    Thermostatistics are preserved.
  • Application to variety of systems unaccounted for
    by B.G. Statistics.
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