Old and new issues in stellar evolution modelling

Abstract

The knowledge of the evolutionary and structural properties of stars has achieved an high level of accuracy and maturity, thanks to an improved understanding of the physics at work in real stars. This notwithstanding, the current generation of stellar models is still affected by several - not always negligible - shortcomings related to our poor knowledge of some thermodynamical processes, nuclear reaction rates, as well as the efficiency of mixing/diffusive processes. These drawbacks have to be properly taken into account, when comparing theory with observations to derive evolutionary properties of both resolved and unresolved stellar populations. This paper reviews (some of) the major sources of uncertainty for the main evolutionary stages. <P />