  In this thesis I examine several different concepts of black hole entropy in
order to understand whether they describe the same quantity. I look at
statistical and entanglement entropies, Wald entropy and Carlip's entropy from
conformal field theory, and compare their behavior in a few specific aspects:
divergence at the BH horizon, dependence on space time curvature and behavior
under a geometric variation. I find that statistical and entanglement entropy
may be similar but they seem to differ from the entropy of Wald and Carlip.
Chapters 2 and 3 overlap with 1010.4157 and 1310.3938. Chapter 4 does not
appear elsewhere.
