I wrote an ode to Physics; I narrate our love affair; I confess how I think about it; I admit my thirst for the complete knowledge of its laws; I yearn for its end!

Trying to understand how the natural world works, I dedicated half of my academic career to research. I devoted the other half to teaching, communication, and spreading what I learned. When I started, three decades ago, I was taught that we were one step away from the end of Physics, a breath away from the Theory of Everything. Today, we are even further from the "thread" that we were ready to "cut" thirty years ago.

Everything we know today about Physics seems like an island surrounded by the ocean of the unexplored. The physicist's mind ignites when realizing how much more there is to learn. I did not write this book to narrate the evolution of Physics, nor to envision its future (since I do not know it, and I suspect the road will be long). I wrote it because I want to talk to you about what I know we do not know. I invite you on an endless intellectual journey, with the three "pillars" of modern physics as stations: relativity, quantum mechanics, and thermodynamics. And at the end of the journey, the mystery of dark matter, dark energy, the loops of quantum gravity, the theory of M, and the grand unification.

What else do you want to feel awe and admiration? How is it possible not to love Physics?