Fluctuations of Conserved Charges

In this chapter we introduce one of the most promising set of observables for the comparison of lattice QCD results to experimental measurements: fluctuations and correlations of conserved charges. After their definition and relation to probability distributions, we discuss their relevance in determining chemical freeze-out parameters, critical point location and the chiral phase transition. The chapter ends with a compilation of lattice QCD results on these quantities. Their comparison to experimental data is discussed in Chap. 7.