On a linear hyperbolic equation with smooth coefficients without solutions

Comparison of Some Solution Concepts for Linear First-order Hyperbolic Differential Equations with Non-smooth Coefficients

We discuss solution concepts for linear hyperbolic equations with coefficients of regularity below Lipschitz continuity. Thereby our focus is on theories which are based either on a generalization of the method of characteristics or on refined techniques concerning energy estimates. We provide a series of examples both as simple illustrations of the notions and conditions involved but also to s...

Remarks on Fundamental Solutions to Schrödinger Equation with Variable Coefficients

Smooth Roots of Hyperbolic Polynomials with Definable Coefficients

We prove that the roots of a definable C∞ curve of monic hyperbolic polynomials admit a definable C∞ parameterization, where ‘definable’ refers to any fixed o-minimal structure on (R,+, ·). Moreover, we provide sufficient conditions, in terms of the differentiability of the coefficients and the order of contact of the roots, for the existence of Cp (for p ∈ N) arrangements of the roots in both ...

Exact Solutions to a Generalized BBM Equation with Variable Coefficients

An auxiliary equation technique is applied to investigate a generalized Benjamin-Bona-Mahony equation with variable coefficients. Many exact traveling wave solutions are obtained which include algebraic solutions, solitons, solitary wave solutions and trigonometric solutions. Mathematics Subject Classification: 35Q53, 35B35

Viscous approach for Linear Hyperbolic Systems with Discontinuous Coefficients

— We introduce small viscosity solutions of hyperbolic systems with discontinuous coefficients accross the fixed noncharacteristic hypersurface {xd = 0}. Under a geometric stability assumption, our first result is obtained, in the multi-D framework, for piecewise smooth coefficients. For our second result, the considered operator is ∂t+a(x)∂x, with sign(xa(x)) > 0 (expansive case not included i...