Good Quote by Richard P. Feynman

Quantum field theory was originally developed for the treatment of electrodynamics, immediately after the completion of quantum mechanics and the discovery of the Dirac…

— David Gross

With the exception of gravitation and radioactivity, all of the phenomena known to physicists and chemists in 1911 have their ultimate explanation in the…

— Richard P. Feynman

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

— Michio Kaku

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

“Every problem in quantum physics had to be first “solved” using classical physics, and then be reworked by the judicious insertion of quantum numbers…

— John Gribbin

The problem is that replacement of Quantum Mechanics by Quantum Field Theory is still very demanding.

— Martin Fleischmann

I liked quantum mechanics very much. The subject was hard to understand but easy to apply to a large number of interesting problems.

— Willis Lamb

In subjects that physicists think of as purely quantum, classical ideas and classical computational techniques can often be powerful.

— Kip Thorne

No. I had successfully solved the difficulty of finding a description of the electron which was consistent with both relativity and quantum mechanics. Of…

— Paul Dirac

Turbulence is the most important unsolved problem of classical physics.

— Richard P. Feynman

While many questions about quantum mechanics are still not fully resolved, there is no point in introducing needless mystification where in fact no problem…

— Murray Gell-Mann

“Realizing its fundamental importance in understanding spectral lines, in atomic physics and in the theory of how light and electrons interact, quantum electrodynamics, Pauli…

— Arthur I. Miller