On the equivalence of Prony and Lanczos methods for Euclidean correlation functions

Abstract We investigate the oblique Lanczos method recently put forward in Ref. [1] for analysing Euclidean correlators in lattice field theories and show that it is analytically equivalent to the well known Prony Generalised Eigenvalue Method (PGEVM). Moreover, we discuss that the signal-to-noise problem is not alleviated by either of these two methods. Still, both methods show clear advantages when compared to the standard effective mass approach.