From history, it can be traced that fundamental physics began the twentieth century with the revolution of two great important theories in physics namely: relativity and quantum mechanics. On one hand, a good number of years of the second half of the century was devoted to the construction of a theoretical structure with a view of unifying these radical ideas. On the other hand, this foundation has also led us to a number of paradoxes in our understanding of nature. Many attempts to make sense of quantum mechanics and gravity at the smallest distance scales lead inexorably to the conclusion that space-time is an approximate notion that must emerge from more primitive building blocks. Furthermore, violent short-distance quantum fluctuations in the vacuum seem to make the existence of a macroscopic world wildly implausible, and yet we live comfortably in a huge universe. Now, what, if anything, tames these fluctuations? Why is there a macroscopic universe? These are two of the central theoretical challenges of fundamental physics in the twenty-first century. In this summary, we describe the circle of ideas surrounding these questions, as well as some of the theoretical and experimental fronts on which they are being attacked and predict what the future holds for theoretical particle physics.