J. Robert Oppenheimer Quotes

The development of quantum mechanics early in the twentieth century obliged physicists to change radically the concepts they used to describe the world.

We appear to have form, but we are like a whirlpool. We appear to have form, but we are just whirling electrons.

I like relativity and quantum theories because I don't understand them and they make me feel as if space shifted about like a swan that can't settle, refusing to sit still and be measured; and as if the atom were an impulsive thing always changing its mind.

Subatomic particles do not exist but rather show 'tendencies to exist', and atomic events do not occur with certainty at definite times and in definite ways, but rather show 'tendencies to occur'.

The more precise the measurement of position, the more imprecise the measurement of momentum, and vice versa.

If I say [electrons] behave like particles I give the wrong impression; also if I say they behave like waves. They behave in their own inimitable way, which technically could be called a quantum mechanical way. They behave in a way that is like nothing that you have seen before.

If we look at the way the universe behaves, quantum mechanics gives us fundamental, unavoidable indeterminacy, so that alternative histories of the universe can be assigned probability.

The principle that light can be in two places at the same time is absolutely extraordinary.

We have to have a combination of general relativity that describes the warping of space and time, and quantum physics, which describes the uncertainties in that warping and how they change.

The world is not made up of particles and waves and beams of light with a definite existence. Instead, the world works in a much more exploratory way. It is aware of all the possibilities at once and trying them out all the time. That is a hard thing to picture.

We talk about quantum weirdness and things being in two places at once, but it all involves atoms and molecules, stuff we don't normally interact with.

The qubit acts as a bridge between the microscopic and the macroscopic worlds.

Now, what that means is that there is fundamental indeterminacy from quantum mechanics, but besides that there are other sources of effective indeterminacy.

In relativity, movement is continuous, causally determinate and well defined, while in quantum mechanics it is discontinuous, not causally determinate and not well defined.

While classical mechanics correctly predicts the behavior of large objects such as tennis balls, to predict the behavior of small objects such as electrons, we must use quantum mechanics.

I had set out to disprove quantum field theory - and the opposite occurred! I was shocked.

Nevertheless, all of us who work in quantum physics believe in the reality of a quantum world, and the reality of quantum entities like protons and electrons.

If I realize that actually there's quantum mechanics happening around us all the time in some macroscopic, interconnected way, then that doesn't change my perception of it, that doesn't change my interaction with it; it just changes how I view my interaction.

If we have an atom that is in an excited state and so is going to emit a photon, we cannot say when it will emit the photon. It has a certain amplitude to emit the photon at any time, and we can predict only a probability for emission; we cannot predict the future exactly.

When one studies the properties of atoms, one found that the reality is far stranger than anybody would have invented in the form of fiction. Particles really do have the possibility of, in some sense, being in more than one place at one time.

There certainly is a tension between the relativity of simultaneity and non-locality in quantum theory, but it's not strong enough to add up to a falsification of either side by itself.

Quantum mechanics brought an unexpected fuzziness into physics because of quantum uncertainty, the Heisenberg uncertainty principle.

Quantum mechanics brought an unexpected fuzziness into physics because of quantum uncertainty, the Heisenberg uncertainty principle. String theory does so again because a point particle is replaced by a string, which is more spread out.

It's indeed surprising that replacing the elementary particle with a string leads to such a big change in things. I'm tempted to say that it has to do with the fuzziness it introduces.

Spreading out the particle into a string is a step in the direction of making everything we're familiar with fuzzy. You enter a completely new world where things aren't at all what you're used to.