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====== What We Know and What We Want to Know About Quantum Gravity ====== **Ilya Shapiro, Ph.D.** \\ //Universidade Federal de Juiz de Fora, MG, Brazil// <blockquote> The construction of successful quantum gravity (QG) theory is sometimes seen as a universal key to all problems of fundamental physics. This expectation is especially popular in strong theory which is sometimes aspired to be the "theory of everything". At the same time known versions of consistent QG involve an enormous or even infinite amount of fine-tuning of hidden parameters, which can not be explained on the background of our present understanding of the nature. One can argue that this should remain true even for yet unknown versions of QG. The situation can be compared to the one with the cosmological constant problem, where the minimal necessary fine-tuning concerns only one parameter and is "only" 55 (at least) orders of magnitude strong. The general situation can be seen as a kind of a natural limit which restricts our understanding of the origin of fundamental forces. </blockquote>