83 research outputs found
New type of extreme value statistics
We investigate the extreme value statistics connected with the dilute Random
Energy Model with integer couplings. New universality class is found.Comment: latex, corrected, new universality class is consequence of
discreteness of original distributio
8 levels of harmony and 8 concepts of Complex Systems
A set of general physical principles is proposed as the structural basis for
the theory of complex systems. First the concept of harmony is analyzed and its
different aspects are uncovered. Then the concept of reflection is defined and
illustrated by suggestive examples. Later we propose the principle of (random)
projection of symmetrically expanded prereality as the main description method
of complex systems.Comment: 4 pages, minor corrections in modality principl
Spin glasses at imaginary temperature
We consider spherical p-spin glass and p-spin glass models at imaginary
temperatures. Imaginary temperatures are special case, when order parameters
are real value numbers. Here there is a some antiferromagnetic like order.Comment: latex, 5 page
Random Energy Model as a paradigm of complex systems
A quadratic extension of REM has been treated. Discussed here is the origin
of relation of REM to strings and other complex physical phenomena. Two basic
features of the REM class of complex phenomena were identified: the double
thermodynamic reflection (a hierarchy of free energies) including the strong
reflection at the upper level (the free energy on the order of a logarithm of
the degrees of freedom) and the loss (complete or partial) of the local
symmetry property. Two main classes of complex phenomena related to REM are
seen: the spin glass phase of REM and the boundary the spin glass-ferromagnetic
phases. Some examples of physics interest are analyzed from this viewpoint.Comment: latex, The English is correcte
Simplified dynamics for glass model
In spin glass models one can remove minimization of free energy by some order
parameter. One can consider hierarchy of order parameters. It is possible to
divide energy among these parts. We can consider relaxation process in glass
system phenomonologically, as exchange of energy between 2 parts. It is
possible to identify trap points in phase space. We suggest some
phenomonological approximation-truncated Langevine.
The mean field statics is used to introduce a phenomenologic dynamics as its
natural extension.
Purely kinetical phase transitions are investigated..Comment: revtex, 3 page
Multiscaling at ferromagnetic-spin glass transition point of Random Energy Model and complexity
We calculate moments of free energy's finite size correction for the
transition point between ferromagnetic and spin glass phases. We find, that
those moments scale with the number of spins with different critical indices,
characteristic for the multiscaling. This critical point corresponds to
threshold of errorless coding for a gaussian noisy channel. We are give the
definition of statistical complexity using this free energy approach.Comment: 9 pages, late
Imitation of 2d quantum field theory by means of REM like models
An imitation of 2d field theory is formulated by means of a model on the
hierarchic tree (with branching number close to one) with the same potential
and the free correlators identical to those of 2d ones. Such a model possesses
some features of original models for certain scale invariant theories. For the
case of 2d conformal models it is possible to derive exact results. The
renormalization group equation for the free energy is a reaction-diffusion
equation, which is noise-free KPZ equation with an additional linear term. For
the case of Liouville model and strings these models on trees may be naturally
expressed via the Random Energy Model. This correspondence is used to identify
the phase structure of strings for analytical continuation of DDK expressions.
A phase transition is found for spherical strings a bit below three dimensions.Comment: latex, 17 page
The harmony, reflection and other principles of complex systems
A set of general physical principles is proposed as the structural basis for
the theory of complex systems. First the concept of harmony is analyzed and its
different aspects are uncovered. Then the concept of reflection is defined and
illustrated by suggestive examples. Later we propose the principle of (random)
projection of symmetrically expanded prereality as the main description method
of complex systems.Comment: 11 pages,latex, more examples are added to the tex
Multi-access channels in quantum information theory
The multi-access channels in quantum information theory are considered.
Classical messages from independent sources, which are represented as some
quantum states, are transported by a channel to one address. The messages can
interact with each other and with external environment. After statement of
problem and proving some general results we investigate physically important
case when information is transported by states of electromagnetic field.
One-way communication by noisy quantum channels is also considered.Comment: LaTex file, 12 page
Finite Size Effects for the Dilute Coupling Derrida Model
We consider paramagnetic, spin-glass and ferromagnetic phases. At model
gives for the some values of connectivity (near the critical) extremal
suppression of finite size effects (decoding error probability).Comment: LaTeX file, 13 pages, acknowledgments are correcte
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