Stationary structures in a classical isotropic two-dimensional continuous Heisenberg
ferromagnetic spin system are studied in the framework of the (2 + 1)-dimensional
LandauLifshitz model. It is established that in the case of S(r, t) = S(r - vt) the
LandauLifshitz equation is closely related to...
A family of special cases of the integrable Euler equations on so(n) introduced by
Manakov in 1976 is considered. The equilibrium points are found and their stability
is studied. Heteroclinic orbits are constructed that connect unstable equilibria and
are given by the orbits of certain 1-parameter...
The sequence of period 6 starting with 1, 1, 0, -1, -1, 0 appears in many different
disguises in mathematics. Various q-versions of this sequence are found, and their
relations with Euler's pentagonal numbers theorem and Chebyshev polynomials are
The motto on Cardinal Newman's tomb ought
The characteristic feature of the Kepler Problem is the existence of the so-called
LaplaceRungeLenz vector which enables a very simple discussion of the properties
of the orbit for the problem. It is found that there are many classes of problems, some
closely related to the Kepler Problem and others...