This paper presents the fundamentals of quantum gravity, one of the two pillars of the grand unified theory (GUT) and its technological applications. GUT is a physical theory, i.e., a mathematical space where the basic premises or axioms are laws of nature. Therefore, GUT inherits the rigor of mathematics, its language, as a deductive system. Proposed by Albert Einstein in the 1920s to unify the four forces of nature-gravity, electromagnetism and the weak and strong forces of quantum physics-it did not materialize until the discovery of the superstring, fundamental building block of matter (1997) as a necessary step to solve the 200-year old gravitational n-body problem. The solution yielded 9 natural laws of GUT beyond the four laws of thermodynamics, Newton's three laws of motion and his universal law of gravitation. True to its name, what started with the narrow objective of unifying the four forces of nature, GUT now unifies the natural sciences in the sense that every natural science field is an extension of GUT plus natural laws specific to that field. Moreover, every natural phenomenon (appearance of nature) is explained by natural laws. Most of all, GUT explains how nature works which makes it the basis for designing a class of technologies called GUT technologies. We focus on two of them: (1) Technology for massive generation of electric power (2) Magnetic charger for battery cars and vehicles. Both technologies run on the free, clean, indestructible and inexhaustible dark matter that is abundant everywhere around us using magnets alone. Moreover, the paper offers improvement on the magnetic train which also runs on the clean, free and indestructible dark matter using magnets alone. Only China, Japan and South Korea own and operate magnetic trains.