Speaker
Description
A broad class of physical observables can be expressed in terms of smeared spectral functions. Important examples include the hadronic vacuum polarization contribution to the muon g−2, hadronic τ decays, inclusive semileptonic B and D decays, and amplitudes for rare processes such as B→Kl+l−. In recent years, a variety of methods have been proposed to reconstruct or constrain such spectral functions from Euclidean correlators and related inputs. However, the inverse problem is intrinsically ill-posed, making it difficult to obtain fully reliable, model-independent results with controlled uncertainties. In this talk, I will summarize recent developments, discuss the opportunities offered by smeared spectral observables, and highlight the main challenges that remain.