Evolution models with base substitutions, insertions, deletions and selection (2009)
The evolution model with parallel mutation-selection scheme is solved for the case when selection is accompanied by base substitutions, insertions, and deletions. The fitness is assumed to be either...
Thermodynamics of adiabatic feedback control (2008)
Allahverdyan, A. E., Saakian, D. B.
We study adaptive control of classical ergodic Hamiltonian systems, where the controlling parameter varies slowly in time and is influenced by system's state (feedback). An effective adiabatic...
Quasispecies Theory for Multiple-Peak Fitness Landscapes (2006)
Saakian, D. B., Munoz, E., Hu, Chin-Kun, Deem, M. W.
We use a path integral representation to solve the Eigen and Crow-Kimura molecular evolution models for the case of multiple fitness peaks with arbitrary fitness and degradation functions. In the...
Adiabatic feedback control of Hamiltonian systems (2006)
Allahverdyan, A. E., Petrosyan, K. G., Saakian, D. B.
We study feedback control of classical Hamiltonian systems with the controlling parameter varying slowly in time. The control aims to change system's energy. We show that the control problems can be...
The results by E. Gardner and B.Derrida have been enlarged for the complex temperatures and complex numbers of replicas. The phase structure is found. There is a connection with string models and...
Spin glasses at imaginary temperature (2001)
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...
An imitation of 2d field theory is formulated by means of a model on the hierarhic tree (with branching number close to one) with the same potential and the free correlators identical to 2d...
Imitation of 2d quantum field theory by means of REM like models (2001)
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...
8 levels of harmony and 8 concepts of Complex Systems (2001)
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...
The harmony, reflection and other principles of complex systems (2000)
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...
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...
Ultrametric space cut instead of 2d one in 2d quantum field models (2000)
It is possible to formulate 2d field theory on the ultrametric space with the free correlators identical to 2d correlators and the same potential. Such model should carry some features of original...
Model glasses coupled to two different heat baths (2000)
Allahverdyan, A., Nieuwenhuizen, T.M., Saakian, D.B.
In a p-spin interaction spherical spin-glass model both the spins and the couplings are allowed to change with time. The spins are coupled to a heat bath with temperature T, while the coupling...
Broadcasting classical information through quantum channel (2000)
Allahverdyan, A., Saakian, D.B.
We consider transmission of classical information through a quantum channel from one sender to several receivers. In contrast to quantum information, classical information carried by two...
Simplified dynamics for glass model (1999)
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...
Random Energy Model as a paradigm of complex systems (1999)
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...
Model glasses coupled to two different heat baths (1999)
Allahverdyan, A. E., Nieuwenhuizen, Th. M., Saakian, D. B.
In a $p$-spin interaction spherical spin-glass model both the spins and the couplings are allowed to change in the course of time. The spins are coupled to a heat bath with temperature $T$, while the...
Complex temperatures zeroes of partition function in spin-glass models (1999)
An approximate method is proposed for investigating complex-temperature properties of real-dimensional spin-glass models. The method uses the complex-temperature data of the ferromagnetic model on...
New type of extreme value statistics (1999)
We investigate the extreme value statistics connected with the dilute Random Energy Model with integer couplings. New universality class is found.
Random Energy Model at Complex Temperatures (1999)
The complete phase diagram of Random Energy Model (REM) is obtained for complex temperatures using the method proposed by Derrida. We find the density of zeroes for statistical sum. Then the method...
About optimal measurements in quantum hypothesizes testing (1998)
Allahverdyan, A. E., Saakian, D. B.
We consider the problem of a state determination for a two-level quantum system which can be in one of two nonorthogonal mixed states. It is proved that for the two independent identical systems the...
Spin-glass model with partially annealed asymmetric bonds (1998)
Allahverdyan, A. E., Saakian, D. B.
We have considered the two-spin interaction spherical spin-glass model with asymmetric bonds (coupling constants). Besides the usual interactions between spins and bonds and between the spins and a...
Allahverdyan, A. E., Saakian, D. B.
A strengthened Lindblad inequality has been proved. We have applied this result for proving a generalized $H$-theorem in non equilibrium thermodynamics. Information processing also can be considered...
The broadcast quantum channel for classical information transmission (1998)
Allahverdyan, A. E., Saakian, D. B.
It is well known that quantum theory forbids the exact copying of an unknown quantum state. Therefore in broadcasting of classical information by a quantum channel an additional contribution to the...
Multi-access channels in quantum information theory (1997)
Allahverdyan, A. E., Saakian, D. B.
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...
Saakian, D. B., Nieuwenhuizen, Th. M.
A Gaussian variational approximation is often used to study interfaces in random media. By considering the 1+1 dimensional directed polymer in a random medium, it is shown here that the variational...
Data processing in quantum information theory (1997)
Allahverdyan, A. E., Saakian, D. B.
The strengthened data processing inequality have been proved. The general theory have been illustrated on the simple example.
Converse coding theorems for quantums source and noisy channel (1997)
Allahverdyan, A. E., Saakian, D. B.
The weak converse coding theorems have been proved for the quantum source and channel. The results give the lower bound for capacity of source and the upper bound for capacity of channel. The...
Spherical P-spin glass at $P\to\infty$ and the information storing by continuous spins (1996)
The $P\to\infty$ limit was considered in the spherical P-spin glass. It is possible to store information in the vacuum configuration of ferromagnetic phase. Maximal allowed level of noise was...
Finite Size Effects for the Dilute Coupling Derrida Model (1995)
Allakhverdyan, A. E., Saakian, D. B.
We consider paramagnetic, spin-glass and ferromagnetic phases. At $T=0$ model gives for the some values of connectivity (near the critical) extremal suppression of finite size effects (decoding error...