by Valery Khoze
Abstract The LHC collider at CERN is performing extremely well, and has a potential of becoming a precision machine. This, in turn, requires an accurate luminosity calibration. Last year the luminosity measurements at the LHC reached a 10% level accuracy, and the precision of around 5% is on the table. In this talk we address the importance of knowing the cross section scale with high precision and discuss the main 'indirect' methods of luminosity calibration from the theoretical perspective. The main aim is to identify the issues which require further theoretical efforts and to evaluate the size of expected theoretical uncertainties in different approaches.