Yepeng Xing, Valery Romanovski
We prove existence results for second-order impulsive differential equations with antiperiodic boundary value conditions in the presence of classical fixed point theorems. We also obtain the...
Yepeng Xing, Valery Romanovski
We prove existence results for second-order impulsive differential equations with antiperiodic boundary value conditions in the presence of classical fixed point theorems. We also obtain the...
Semiclassical analysis of Wigner functions (2002)
Veble, Gregor, Robnik, Marko, Romanovski, Valery
In this work we study the Wigner functions, which are the quantum analogues of the classical phase space density, and show how a full rigorous semiclassical scheme for all orders of \hbar can be...
The Center Variety of Polynomial Differential Systems (2000)
Jarrah, Abdul Salam, Laubenbacher, Reinhard, Romanovski, Valery
We investigate the symmetry component of the center variety of polynomial differential systems, corresponding to systems with an axis of symmetry in the real plane. We give a general algorithm to...
On WKB Series for the Radial Kepler Problem (2000)
Romanovski, Valery, Robnik, Marko
We obtain the rigorous WKB expansion to all orders for the radial Kepler problem, using the residue calculus in evaluating the WKB quantization condition in terms of a complex contour integral in the...
On the semiclassical expansion for 1-dim $x^N$ potentials (2000)
Robnik, Marko, Romanovski, Valery
In the present paper we study the structure of the WKB series for the polynomial potential $V(x)=x^N$ ($N$ even). In particular, we obtain relatively simple recurrence formula of the coefficients...