All integral laws of spectral lines and of atomic theory spring originally from the quantum theory. It is the mysterious organon on which Nature plays her music of the spectra, and according to the rhythm...

There was, I think, a feeling that the best science was that done in the simplest way. In experimental work, as in mathematics, there was ‘style’ and a result obtained with simple equipment was more...

Physicists have come to realize that mathematics, when used with sufficient care, is a proven pathway to truth.

My God, what a sensation to be an atom in the scheme of such grandiosity. The allurement, the jazz, and the physics of it all . . .

I remember discussions with Bohr which went through many hours till very late at night and ended almost in despair; and when at the end of the discussion I went alone for a walk in...

The miracle of the appropriateness of the language of mathematics for the formulation of the laws of physics is a wonderful gift which we neither understand nor deserve. We should be grateful for it and...

While Newton seemed to draw off the veil from some of the mysteries of nature, he showed at the same time the imperfections of the mechanical philosophy, so agreeable to the natural vanity and curiosity...

It is worth noting that a wrong folkoric definition of an Inertial Frame in the Popular Science literature (even in text books) reads that ‘it is a frame in uniform motion’. We know very well...

…in microphysics the observer interferes with the experiment in a way that can’t be measured and that therefore can’t be eliminated. No natural laws can be formulated, saying “such-and-such will happen in every case.” All...

Time is the key to the heart of physics.

How wonderful that we have met with a paradox. Now we have some hope of making progress.

Individual events. Events beyond law. Events so numerous and so uncoordinated that, flaunting their freedom from formula, they yet fabricate firm form.

In some sense, gravity does not exist; what moves the planets and the stars is the distortion of space and time.

The role played by time at the beginning of the universe is, I believe, the final key to removing the need for a Grand Designer, and revealing how the universe created itself. … Time itself...

It has today occurred to me that an amplifier using semiconductors rather than vacuum is in principle possible.[Laboratory notebook, 29 Dec 1939.]

This is why magic is worse even than quantum physics. Because, while both spit in the eye of common sense, I’ve never yet had a Higgs bosun turn up and try to have a conversation...

Thus, by science I mean, first of all, a worldview giving primacy to reason and observation and a methodology aimed at acquiring accurate knowledge of the natural and social world. This methodology is characterized, above...

All creation necessarily ends in this: Creators, powerless, fleeing from the things they have wrought.

The bright sun was extinguish’d, and the starsDid wander darkling in the eternal space.

[When asked by a student if he believes in any gods]Oh, no. Absolutely not… The biggest advantage to believing in God is you don’t have to understand anything, no physics, no biology. I wanted to...

A sound Physics of the Earth should include all the primary considerations of the earth’s atmosphere, of the characteristics and continual changes of the earth’s external crust, and finally of the origin and development of...

O. Hahn and F. Strassmann have discovered a new type of nuclear reaction, the splitting into two smaller nuclei of the nuclei of uranium and thorium under neutron bombardment. Thus they demonstrated the production of...

Metaphysics is the other end of physics.

We know that energy can not be created nor destroyed but can be changed in it’s form. If it can not be formed then it can not exist. We may not exist.

Through Jung [Pauli] became very interested in various kinds of mysticism, including Jewish mysticism. This led Pauli to develop a friendship with Gershom Scholem, the world’s greatest authority in that field and in the Cabala,...

…I am not, however, militant in my atheism. The great English theoretical physicist Paul Dirac is a militant atheist. I suppose he is interested in arguing about the existence of God. I am not. It...

Programmed by quanta, physics gave rise first to chemistry and then to life; programmed by mutations and recombination, life gave rise to Shakespeare; programmed by experience and imagination, Shakespeare gave rise to Hamlet.

Quantum theory provides us with a striking illustration of the fact that we can fully understand a connection though we can only speak of it in images and parables.

Relativity applies to physics, not ethics

If you can’t illustrate ‘it’, ‘it’ doens’t belong in Physics as a noun! You can’t put an article in front. You can’t put a verb after!

For [Wolfgang] Pauli the central problem of electrodynamics was the field concept and the existence of an elementary charge which is expressible by the fine-structure constant … 1/137. This fundamental pure number had greatly fascinated...

Both [Quine and Feyerabend] want to revise a version of positivism. Quine started with the Vienna Circle, and Feyerabend with the Copenhagen school of quantum mechanics. Both the Circle and the school have been called...

We need science education to produce scientists, but we need it equally to create literacy in the public. Man has a fundamental urge to comprehend the world about him, and science gives today the only...

Planck…and Bohr…have invented systems containing electrons of which the motion produces no effect upon external charges…[N]ot only [is this] inconsistent with the accepted laws of electromagnetism, but I may add, is logically objectionable, for that...

There was a sense that the one true theory had been discovered. Nothing else was important or worth thinking about. Seminars devoted to string theory sprang up at many of the major universities and research...

I have tried to read philosophers of all ages and have found many illuminating ideas but no steady progress toward deeper knowledge and understanding. Science, however, gives me the feeling of steady progress: I am...

It was like bouncing tennis balls off a mystery piece of furniture and deducing, from the direction in which the balls ricocheted, whether it was a chair or a table or a Welsh dresser.

The fundamental laws of the universe which correspond to the two fundamental theorems of the mechanical theory of heat.1. The energy of the universe is constant.2. The entropy of the universe tends to a maximum.

Physicists often quote from T. H. White’s epic novel The Once and Future King, where a society of ants declares, ‘Everything not forbidden is compulsory.’ In other words, if there isn’t a basic principle of...

I don’t mind not knowing. It doesn’t scare me.

Here at great expense,’ [Colonel Groves] moaned to Oppenheimer, ‘the government has assembled the world’s largest collection of crackpots.

Love was actually more like calculus or physics. What was the half-life of love? Did it have cosigns and slopes, or quarks that morphed from wave to particle faster than you could say, please don’t...

Free will is the sensation of making a choice. The sensation is real, but the choice seems illusory. Laws of physics determine the future.

It’s hard to build models of inflation that don’t lead to a multiverse. It’s not impossible, so I think there’s still certainly research that needs to be done. But most models of inflation do lead...

Nobody knows how the stand of our knowledge about the atom would be without him. Personally, Bohr is one of the amiable colleagues I have met. He utters his opinions like one perpetually groping and...

I have been able to solve a few problems of mathematical physics on which the greatest mathematicians since Euler have struggled in vain … But the pride I might have held in my conclusions was...

I started studying law, but this I could stand just for one semester. I couldn’t stand more. Then I studied languages and literature for two years. After two years I passed an examination with the...

Politics follows the lines of physics: every action creates an equal and opposite reaction.

Mathematics began to seem too much like puzzle solving. Physics is puzzle solving, too, but of puzzles created by nature, not by the mind of man.

The language of physics is not math, but physics.