257,457 research outputs found
On pre-periods of discrete influence systems
AbstractWe investigate mappings of the form g = ƒA where ƒ is a cyclically monotonous mapping of finite range and A is a linear mapping given by a symmetric matrix. We give some upper bounds on the pre-period of g, i.e. the maximum q for which all g(x),g2(x),…,gq(x) are distinct
The effect of temperature on generic stable periodic structures in the parameter space of dissipative relativistic standard map
In this work, we have characterized changes in the dynamics of a
two-dimensional relativistic standard map in the presence of dissipation and
specially when it is submitted to thermal effects modeled by a Gaussian noise
reservoir. By the addition of thermal noise in the dissipative relativistic
standard map (DRSM) it is possible to suppress typical stable periodic
structures (SPSs) embedded in the chaotic domains of parameter space for large
enough temperature strengths. Smaller SPSs are first affected by thermal
effects, starting from their borders, as a function of temperature. To estimate
the necessary temperature strength capable to destroy those SPSs we use the
largest Lyapunov exponent to obtain the critical temperature () diagrams.
For critical temperatures the chaotic behavior takes place with the suppression
of periodic motion, although, the temperature strengths considered in this work
are not so large to convert the deterministic features of the underlying system
into a stochastic ones.Comment: 8 pages and 7 figures, accepted to publication in EPJ
Opportunity for Regulating the Collective Effect of Random Expansion with Manifestations of Finite Size Effects in a Moderate Number of Finite Systems
One reports computational study revealing a set of general requirements,
fulfilling of which would allow employing changes in ambient conditions to
regulate accomplishing the collective outcome of emerging active network
patterns in an ensemble of a moderate number of finite discrete systems. The
patterns within all these component systems emerge out of random expansion
process governed by certain local rule. The systems modeled are of the same
type but different in details, finite discrete spatial domains of the expansion
within the systems are equivalent regular hexagonal arrays. The way in which
elements of a component system function in the local information transmission
allows dividing them into two classes. One class is represented by
zero-dimensional entities coupled into pairs identified at the array sites
being nearest neighbors. The pairs preserve their orientation in the space
while experiencing conditional hopping to positions close by and transferring
certain information portions. Messenger particles hopping to signal the pairs
for the conditional jumping constitute the other class. Contribution from the
hopping pairs results in finite size effects being specific feature of
accomplishing the mean expected network pattern representing the collective
outcome. It is shown how manifestations of the finite size effects allow using
changes in parameters of the model ambient conditions of the ensemble evolution
to regulate accomplishing the collective outcome representation.Comment: 22 pages, 10 eps figures, corrected URL address placing in text,
minor editorial correction in sec.2, author e-mail change
Dynamical Tide in Solar-Type Binaries
Circularization of late-type main-sequence binaries is usually attributed to
turbulent convection, while that of early-type binaries is explained by
resonant excitation of g modes. We show that the latter mechanism operates in
solar-type stars also and is at least as effective as convection, despite
inefficient damping of g modes in the radiative core. The maximum period at
which this mechanism can circularize a binary composed of solar-type stars in
10 Gyr is as low as 3 days, if the modes are damped by radiative diffusion only
and g-mode resonances are fixed; or as high as 6 days, if one allows for
evolution of the resonances and for nonlinear damping near inner turning
points. Even the larger theoretical period falls short of the observed
transition period by a factor two.Comment: 17 pages, 2 postscript figures, uses aaspp4.sty. Submitted to Ap
Non-equilibrium steady state in a periodically driven Kondo model
We investigate the Kondo model with time-dependent couplings that are
periodically switched on and off. On the Toulouse line we derive exact
analytical results for the spin dynamics in the steady state that builds up
after an infinite number of switching periods. Remarkably, the algebraic long
time behavior of the spin-spin correlation function remains completely
unaffected by the driving. In the limit of slow driving the dynamics become
equivalent to that of a single interaction quench. In the limit of fast driving
one can show that the steady state cannot be described by some effective
equilibrium Hamiltonian since a naive implementation of the Trotter formula
gives wrong results. As a consequence, the steady state in the limit of fast
switching serves as an example for the emergence of new quantum states not
accessible in equilibrium.Comment: 13 pages, 4 figures; minor changes, version as publishe
Evaluation of Low Permeability, Naturally Fractured Carbonate Reservoir with Pressure Transient Analysis
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