[Heisenberg's seminal 1925 paper initiating quantum…

The quantum entered physics with a jolt. It didn't fit anywhere; it made no sense; it contradicted everything we thought we knew about nature.…

— David C. Cassidy

“One hundred thirty-seven is the inverse of something called the fine-structure constant. ...The most remarkable thing about this remarkable number is that it is…

— Leon M. Lederman

“Margrethe: And when all our eyes are closed, when even the ghosts have gone, what will be left of our beloved world? Our ruined…

— Michael Frayn

“Many scientists have tried to make determinism and complementarity the basis of conclusions that seem to me weak and dangerous; for instance, they have…

— Louis de Broglie

“The uncertainty principle “protects” quantum mechanics. Heisenberg recognized that if it were possible to measure the momentum and the position simultaneously with a greater…

— Richard P. Feynman

We live, I think, in the century of science and, perhaps, even in the century of physics.

— Polykarp Kusch

String theory is 21 st century physics that fell accidentally into the 20th century.

— Edward Witten

“Twentieth-century physics, going full circle back to Heracleitus, postulates that all matter is in motion. In other words, there is no thing, only energy.”

— Camille Paglia

It has become part of the accepted wisdom to say that the twentieth century was the century of physics and the twenty-first century will…

— Freeman Dyson

“I have chosen to talk about one of the founder fathers of twentieth-century physics, Niels Bohr, because in both these respects he was a…

— Jacob Bronowski

Anyone not shocked by quantum mechanics has not yet understood it.

— Niels Bohr

String theory is the most developed theory with the capacity to unite general relativity and quantum mechanics in a consistent manner. I do believe…

— Brian Greene

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

Yes, I am a quantum mechanic! Those darn quantum computers break all the time.

— Seth Lloyd

A popular feel for scientific endeavors should, if possible, be restored given the needs of the twenty-first century. This does not mean that every…

— Walter Isaacson