Gravity Quote by Alan Guth

“The key question for a quantum theory of gravity is then the following: Can we extend to quantum theory the principle that space has…

— Lee Smolin

We're going to need a definitive quantum theory of gravity, which is part of a grand unified theory - it's the main missing piece.

— Kip Thorne

The extreme weakness of quantum gravitational effects now poses some philosophical problems; maybe nature is trying to tell us something new here: maybe we…

— Richard P. Feynman

There was a long history of speculation that in quantum gravity, unlike Einstein's classical theory, it might be possible for the topology of spacetime…

— Edward Witten

“The loop approach to quantum gravity is now a thriving field of research. Many of the older ideas, such as supergravity and the study…

— Lee Smolin

Quantum mechanics as it stands would be perfect if we didn’t have the quantum-gravity issue and a few other very deep fundamental problems.

— Gerard 't Hooft

“Problem 1: Combine general relativity and quantum theory into a single theory that can claim to be the complete theory of nature. This is…

— Lee Smolin

From a theoretical point of view, it is very hard to imagine how gravity could avoid being quantized.

— Alan Guth

“Now, at the outset of the twenty-first century, we stand on the verge of a new revolution. The search for a deeper theory than…

— Marcus Chown

The quest for a quantum gravity is one of the greatest unsolved problems in all of science.

— Michio Kaku

Any two particles in the universe attract each other through the gravitational interaction.

— Lee Smolin

I thought that there must be an easier way to explain how a gravitational wave interacts with matter: If one just looked at the…

— Rainer Weiss