For 10 points, name this mathematician best known as the second namesake of a second-order differential eigenvalue problem along Jacques Sturm.
A function named for this person was the subject of the Polyá conjecture and oscillates infinitely often. This scientist names the measure that is the product the differentials of a Hamiltonian system's coordinates, and a theorem named for him says that the integral of that measure is constant, which implies that the phase space density is constant for a Hamiltonian system. The numbers named for this thinker are transcendental, but arbitrarily close to rationals. A better-known result due to this mathematician which is often used to prove the fundamental theorem of algebra, states that bounded, analytic functions are constant. This man proved the completeness as basis of the solutions to the equation for which he is best known as second namesake. For 10 points, name this mathematician best known as the second namesake of a second-order differential eigenvalue problem along Jacques Sturm.
A function named for this person was the subject of the Polyá conjecture and oscillates infinitely often.
Joseph {Liouville}