Just as the system of the sun, planets and comets is put in motion by the forces of gravity, and its parts persist in their motions, so the smaller systems of bodies also seem to be set in motion by other forces and their particles to be variously moved in relation to each other and, especially, by the electric force.

Quarks came in a number of varieties – in fact, at first, only three were needed to explain all the hundreds of particles and the different kinds of quarks – they are called u-type, d-type, s-type.

It now appears that the way the universe began can indeed be determined, using imaginary time.

I think we all change each other’s paths. I don’t know which law idea that is in physics, but I don’t think any of us can live without affecting one another.

No one undertakes research in physics with the intention of winning a prize. It is the joy of discovering something no one knew before.

Our nature consists in motion; complete rest is death.

Among physicists, I’m respected I hope.

It’s time for the human race to enter the solar system.

I can calculate the motion of heavenly bodies, but not the madness of people.

I tend to approach things from a physics framework. And physics teaches you to reason from first principles rather than by analogy.

The same law takes place in a system, consisting of many bodies, as in one single body, with regard to their persevering in their state of motion or of rest. For the progressive motion, whether of one single body or of a whole system of bodies, is always to be estimated from the motion of the center of gravity.

There is no physical law precluding particles from being organised in ways that perform even more advanced computations than the arrangements of particles in human brains.

I think you should always bear in mind that entropy is not on your side.

To every action there is always opposed an equal reaction.

You have a row of dominoes set up; you knock over the first one, and what will happen to the last one is that it will go over very quickly.

And yet it moves.

To practice five things under all circumstances constitutes perfect virtue; these five are gravity, generosity of soul, sincerity, earnestness, and kindness.

If a projectile were deprived of the force of gravity, it would not be deflected toward the earth but would go off in a straight line into the heavens and do so with uniform motion, provided that the resistance of the air were removed.

Susceptibility to the highest forces is the highest genius.

It may be that there is no such thing as an equable motion, whereby time may be accurately measured. All motions may be accelerated or retarded, but the true, or equable, progress of absolute time is liable to no change.

Atheism is so senseless. When I look at the solar system, I see the earth at the right distance from the sun to receive the proper amounts of heat and light. This did not happen by chance.

I think the discovery of supersymmetric partners for the known particles would revolutionize our understanding of the universe.

My background educationally is physics and economics, and I grew up in sort of an engineering environment – my father is an electromechanical engineer. And so there were lots of engineery things around me.

Everything starts somewhere, although many physicists disagree.

M-theory is the unified theory Einstein was hoping to find.

Physics has a history of synthesizing many phenomena into a few theories.

Gravity must be caused by an Agent acting constantly according to certain laws, but whether this Agent be material or immaterial I have left to the consideration of my readers.

In order to arrive at knowledge of the motions of birds in the air, it is first necessary to acquire knowledge of the winds, which we will prove by the motions of water in itself, and this knowledge will be a step enabling us to arrive at the knowledge of beings that fly between the air and the wind.

Some desire is necessary to keep life in motion, and he whose real wants are supplied must admit those of fancy.

Man can be understood only by ascending from physics, chemistry, biology, and geology. In other words, he is first of all a cosmic problem.

When we wrote the Constitution, the intention was to give the commander in chief the authority how to use the forces when you authorize him to be able to use the forces.

They say the universe is expanding. That should help with the traffic.

My first popular book, ‚A Brief History of Time,‘ aroused a great deal of interest, but many found it difficult to understand.

I tell you the solemn truth, that the doctrine of the Trinity is not so difficult to accept for a working proposition as any one of the axioms of physics.

Chemistry, until my childhood, not that long ago, was regarded as a calculating device. Because you couldn’t reduce to physics. So it’s just some way of calculating the result of experiments. The Bohr atom was treated that way.

The motions which the planets now have could not spring from any natural cause alone, but were impressed by an intelligent Agent.

OK, so what’s the speed of dark?

If you are in a spaceship that is traveling at the speed of light, and you turn on the headlights, does anything happen?

From the point of view of basic physics, the most interesting phenomena are, of course, in the new places, the places where the rules do not work – not the places where they do work! That is the way in which we discover new rules.

The first amazing fact about gravitation is that the ratio of inertial mass to gravitational mass is constant wherever we have checked it. The second amazing thing about gravitation is how weak it is.

The drawing teacher has this problem of communicating how to draw by osmosis and not by instruction, while the physics teacher has the problem of always teaching techniques, rather than the spirit, of how to go about solving physical problems.

Mars is the only place in the solar system where it’s possible for life to become multi-planetarian.

Gravitation is, so far, not understandable in terms of other phenomena.

I think equation guessing might be the best method to proceed to obtain the laws for the part of physics which is presently unknown. Yet, when I was much younger, I tried this equation guessing, and I have seen many students try this, but it is very easy to go off in wildly incorrect and impossible directions.

Most people have no concept of how an automatic transmission works, yet they know how to drive a car. You don’t have to study physics to understand the laws of motion to drive a car. You don’t have to understand any of this stuff to use Macintosh.

It is generally recognised that women are better than men at languages, personal relations and multi-tasking, but less good at map-reading and spatial awareness. It is therefore not unreasonable to suppose that women might be less good at mathematics and physics.

There are only two forces that unite men – fear and interest.

The greatest progress is in the sciences that study the simplest systems. So take, say, physics – greatest progress there. But one of the reasons is that the physicists have an advantage that no other branch of sciences has. If something gets too complicated, they hand it to someone else.

Today, all physicists know from studying Einstein and Bohr that sometimes an idea which looks completely paradoxical at first, if analyzed to completion in all detail and in experimental situations, may, in fact, not be paradoxical.

In some sort of crude sense, which no vulgarity, no humor, no overstatement can quite extinguish, the physicists have known sin; and this is a knowledge which they cannot lose.

We have one planet in our solar system that’s habitable, and that’s the Earth, and space travel can transform things back here for the better. First of all, by just having people go to space and look back on this fragile planet we live on. People have come back transformed and have done fantastic things.

It is theoretically possible to warp spacetime itself, so you’re not actually moving faster than the speed of light, but it’s actually space that’s moving.

We seem gradually to be groping toward an understanding of the world of subatomic particles, but we really do not know how far we have yet to go in this task.

My discovery that black holes emit radiation raised serious problems of consistency with the rest of physics. I have now resolved these problems, but the answer turned out to be not what I expected.

I felt like I might as well have been living in another part of the solar system.

Tardiness often robs us opportunity, and the dispatch of our forces.

I have explained the phenomena of the heavens and of our sea by the force of gravity, but I have not yet assigned a cause to gravity.

Painting is concerned with all the 10 attributes of sight; which are: Darkness, Light, Solidity and Colour, Form and Position, Distance and Propinquity, Motion and Rest.

This most beautiful system of the sun, planets, and comets, could only proceed from the counsel and dominion of an intelligent and powerful Being.

Electrical science has disclosed to us the more intimate relation existing between widely different forces and phenomena and has thus led us to a more complete comprehension of Nature and its many manifestations to our senses.

You can’t blame gravity for falling in love.