“…The field of uncertainty quantification has experienced tremendous growth in the past decade, with many efficient general-purpose computational algorithms developed and some specific theoretical issues mathematically understood; see, for instance, [8,17,18,21,27,28,32,33,34,39,46,47,48,49,58,59,62,73,78,83,86] and references therein for some recent developments in the field. In this work, we investigate uncertainty quantification issues in image reconstruction problems in quantitative photoacoustic tomography (PAT), one of the recent hybrid imaging modality that combines the advantages of the classical ultrasound imaging and optical tomography [16,81,82].…”