Leonard Susskind Quotes

As you say, the way string theory requires all these extra dimensions and this comes from certain consistency requirements about how string should behave and so on.

I'd say many features of string theory don't mesh with what we observe in everyday life.

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

In the book, I make the point that here we have string theory and here we have twistor theory and we don't know if either one of them is the right approach to nature.

String theory is an attempt at a deeper description of nature by thinking of an elementary particle not as a little point but as a little loop of vibrating string.

One of the main successes of string theory is that it has been able to unify the general theory of relativity, which describes gravity, and quantum mechanics.

I came to realise that string theory offers us the best hope of finding a unified theory of all matter and forces.

In many ways, string theory attempts to go beyond Einstein's dream... an all-encompassing description of nature that works at large distances where gravity becomes important as well as small distances where quantum mechanics is important.

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

String theory has had a long and wonderful history. It originated as a technique to try to understand the strong force. It was a calculational mechanism, a way of approaching a mathematical problem that was too difficult, and it was a promising way, but it was only a technique. It was a mathematical technique rather than a theory in itself.

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.

I do feel strongly that string theory is our best hope for making progress at unifying gravity and quantum mechanics.

String theory is not the only theory that can accommodate extra dimensions, but it certainly is the one that really demands and requires it.

One very important aspect of string theory is definitely testable. That was the prediction of supersymmetry, which emerged from string theory in the early '70s.

It's an exaggeration to say that I came up with M-theory.

Einstein was searching for String Theory. It not only reconciles General Relativity to Quantum Mechanics, but it reconciles Science and the Bible as well.

I like to think that Einstein would look at string theory’s journey and smile, enjoying the theory’s remarkable geometrical features while feeling kinship with fellow travelers on the long and winding road toward unification.

There are a lot of good things about string theory, and it's great that some people want to work on it.

If string theory is a mistake, it's not a trivial mistake. It's a deep mistake and therefore kind of worthy.

In order to achieve a true understanding of string theory, some new idea will be required, and most likely, some break with the concepts on which we've traditionally based physical theory.

One of the strangest features of string theory is that it requires more than the three spatial dimensions that we see directly in the world around us. That sounds like science fiction, but it is an indisputable outcome of the mathematics of string theory.

I'm a fan of supersymmetry, largely because it seems to be the only route by which gravity can be brought into the scheme. It's probably not even enough, but it's a way forward to get gravity involved. If you have supersymmetry, then there are more of these particles. That would be my favourite outcome.

We're going to need a definitive quantum theory of gravity, which is part of a grand unified theory - it's the main missing piece.

I just think too many nice things have happened in string theory for it to be all wrong. Humans do not understand it very well, but I just don't believe there is a big cosmic conspiracy that created this incredible thing that has nothing to do with the real world.

So when you ask me how string theory might be tested, I can tell you what's likely to happen at accelerators or some parts of the theory that are likely to be tested.