Leonard Susskind Quotes

And what we know, or think we know, about the universe of space and time is changing very quickly.

Every string theory that's been written down says the speed of light is universal. But other ideas about quantum gravity predict the speed of light has actually increased.

You have to say now that space is something. Space can vibrate, space can fluctuate, space can be quantum mechanical, but what the devil is it?

Why is there space rather than no space? Why is space three-dimensional? Why is space big? We have a lot of room to move around in. How come it's not tiny? We have no consensus about these things. We're still exploring them.

Science predicts that many different kinds of universe will be spontaneously created out of nothing. It is a matter of chance which we are in.

'Eternal inflation,' as it's called - the endless generation of new universes - may be a hyper-cosmic imperative. It seems that it must happen.

General relativity is the cornerstone of cosmology and astrophysics. It has also provided the conceptual basis for string theory and other attempts to unify all the forces of nature in terms of geometrical structures.

Physics grapples with the largest questions the universe presents. 'Where did the totality of reality come from?' 'Did time have a beginning?'

Evolutionary cosmology formulates theories in which a universe is capable of giving rise to and generating future universes out of itself, within black holes or whatever.

It's not completely obvious what gravity is, fundamentally, or what dimensions are, fundamentally. One of these days we'll understand better what we mean, what is the fundamental thing that's given us space in the first place and dimensions of space in particular.

String theory is the most developed theory with the capacity to unite general relativity and quantum mechanics in a consistent manner. I do believe the universe is consistent, and therefore I do believe that general relativity and quantum mechanics should be put together in a manner that makes sense.

We need a theory that goes before the Big Bang, and that's String Theory. String Theory says that perhaps two universes collided to create our universe, or maybe our universe is butted from another universe leaving an umbilical cord. Well, that umbilical cord is called a wormhole.

My present work concerns the problems connected with the theory of elementary particles, the theory of gravitation and cosmology and I shall be glad if I can manage to make some contribution to these important branches of science.

The bedrock nature of space and time and the unification of cosmos and quantum are surely among science's great 'open frontiers.' These are parts of the intellectual map where we're still groping for the truth - where, in the fashion of ancient cartographers, we must still inscribe 'here be dragons.'

According to 'M' theory, ours is not the only universe. Instead, 'M' theory predicts that a great many universes were created out of nothing.

When I was in high school, I was really into string theory and superstring theory and read 'Scientific American.' It's fascinating.

I've always really been into science, and in the last five years I've gotten into theoretical physics and the origins of the universe.

Now, what space ultimately is - I should confess, I think most physicists believe - we don't yet know.

When we understand string theory, we will know how the universe began. It won't have much effect on how we live, but it is important to understand where we come from and what we can expect to find as we explore.

At the same time, new concepts and abstractions flow into the picture, taking up the task of describing the universe without reference to such time or space - abstractions for which our language lacks adequate terms.

According to String Theory, what appears to be empty space is actually a tumultuous ocean of strings vibrating at the precise frequencies that create the 4 dimensions you and I call height, width, depth and time.

One of the weird things about modern physics is that we do find there are apparently these other dimensions that we don't directly experience that explain some aspects of the overall geometry and reality of our universe.

Although we don't know what is outside our universe, astronomers still wonder. Several pictures of what there might be have been dreamed up. An interesting one, called multiverse, has lots of universes. Picture it as a foam of bubbles. Our universe would be one bubble, and we'd be surrounded by lots of other bubbles.

Our best theory of describing space at a fundamental level is probably string theory.

My goal is simple. It is a complete understanding of the universe, why it is as it is and why it exists at all.