A New Determinant for Quantum Chaos

We propose a new type of approximation to quantum determinants, ``quantum Fredholm determinant", and conjecture that, compared to the quantum Selberg zeta functions derived from Gutzwiller semiclassical trace formulas, such determinants have a larger domain of analyticity for Axiom A hyperbolic systems. The conjecture is supported by a numerical investigation of the 3-disk repeller.