Differential operators and their adjoints under integral and multiple point boundary conditions

Differential operators and adjoint systems derived from Green function and Hilbert space

On the Class of Admissable Nonlinearities for Lur'e's Problem

Imposition of conditions on nonlinear function of scalar so that system will be stable or asymptotically stabl

On the Eigenvalues of a Singular Nonself- Adjoint Differential Operator of Second Order

Singular nonself-adjoint differential operator of second order eigenvalue

A general stability criterion for feedback systems

Means for determining stability of feedback systems described by either linear or nonlinear differential equation

Root Locus Asymptotes for the Sum of Two Polynomials of the Same Degree

Root locus asymptotes for sum of two polynomials of same degre

On the Number of L2 Solutions of - y plus Q/t/y Equals Lambda y Where Q/t/ Is Complex Valued

Operator solutions for complex valued second order differential equatio

On the Michailov criterion for exponential polynomials

Michailov criterion for exponential polynomial

Root locus diagrams by digital computer

Adaptation of root locus method to programming on IBM 7074 digital compute

Strongly and Weakly Unstable Anisotropic Quark-Gluon Plasma

Using explicit solutions of the QCD transport equations, we construct an effective potential for an anisotropic quark-gluon plasma which under plausible assumptions holds beyond the Hard Loop approximation. The configurations, which are unstable in the linear response approach, are characterized by a negative quadratic term of the effective potential. The signs of higher order terms can be either negative or positive, depending on the parton momentum distribution. In the case of a Gaussian momentum distribution, the potential is negative and unbound from below. Therefore, the modes, which are unstable for gauge fields of small amplitude, remain unstable for arbitrary large amplitudes. We also present an example of a momentum distribution which gives a negative quadratic term of the effective potential but the whole potential has a minimum and it grows for sufficiently large gauge fields. Then, the system is weakly unstable. The character of the instability is important for the dynamical evolution of the plasma system.Comment: 13 pages, 1 figure, revised, to appear in Phys. Rev.

Laser scattering by density fluctuations of ultra-cold atoms in a magneto-optical trap

We study the spectrum of density fluctuations in the ultra-cold gas of neutral atoms, confined in a magneto-optical trap. We determine the corresponding amplitude and spectra of laser light scattered by this medium. We derive an expression for the dynamical structure function, by using a test particle method. We propose to use the collective laser scattering as a diagnostic method for the microscopic properties of the ultra-cold matter. This will also allow us to check on the atomic correlations which are mediated by the collective mean field inside the gas.Comment: J. Phys. B (in press