Is Quantum Gravity the Ultimate Theory? Is it the Theory of Everything or the Unification of Physics?

The extraordinary scientific breakthroughs, particularly Sir Isaac Newtons theory of Gravity, had led Marquis de Laplace to analyze and predict at the beginning of Nineteenth century that the Universe is completely deterministic. Laplace believed that given a set of initial states or conditions (such as the present states or conditions of the Universe) or the boundary conditions (i. e. the conditions at the boundary of either space or time or space-time, if any, of the Universe) of the Universe, the future states of the Universe can be completely specified for any given particular time in the future i. e. at least in principle, we can predict accurately everything that would happen in the Universe. The only excitation or input required in the Laplaces model of the Universe is that the complete states of the Universe at any particular given time. A boundary condition in space is the state of the Universe at its outer boundary-if any. Based on the total set of laws with appropriate initial or boundary conditions, according to Laplace, we can calculate the complete states of the Universe at any given time in the future. The problems with finding the initial conditions or boundary conditions are many. The two most influential theories in the physical science are the Einsteins the general theory of relativity which represents the macroscopic structure of the Universe very accurately without any fail with observations and the quantum mechanics which describe the microscopic structure of the Universe within the limits of uncertainty principle, it supports all observations without fail of any. The recent trend is that to incorporate gravity in the quantum mechanics to develop a complete theory-the theory of quantum gravity that will describe all possible observations regardless of macroscopic and microscopic structural differences of the Universe. Is that the quantum gravity, if any, will be the ultimate theory of physical science Is unification of physics is possible with quantum gravity Is the quantum gravity will be the theory of everything Or is it the end in sight for the theoretical Physics What should be and must be the main ingredients of such unification of physical science The long standing quests need to be addressed in the process of finding the ultimate theory-the theory of everything to obtain the unification of physics.