Leonard Susskind Quotes

The original project began because we know the universe is expanding. Everybody had assumed that gravity would slow down the expansion of the universe and everything would come to a halt and collapse. The big surprise was it was actually speeding up.

For almost a century, the Universe has been known to be expanding as a consequence of the Big Bang about 14 billion years ago. However, the discovery that this expansion is accelerating is astounding. If the expansion will continue to speed up, the Universe will end in ice.

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

We already have a pretty good knowledge of the universe's mass-energy content, so if we can get a handle on its geometry, then we will be able to work out exactly what the fate of the universe will be.

The geometry, the content, and the fate of the universe are all intricately linked. If you know two, you can deduce the third.

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

It was only about sixty years ago that the expansion of the universe was first observed.

Observations indicate that the universe is expanding at an ever increasing rate. It will expand forever, getting emptier and darker.

We know that the expansion of our universe is accelerating, which means a number called the cosmological constant must be positive.

Most gravity has no known origin. Is it some exotic particle? Nobody knows. Is dark energy responsible for expansion of the universe? Nobody knows.

About the 50th hour, I was going to start thinking about the edge of the universe. Is there an edge? Is this an envelope we're living inside of, or no, does it go onto infinity in both time and space? And there's nothing like swimming for 50 hours in the ocean that gets you thinking about things like this.

If the rate of expansion one second after the Big Bang had been smaller by even one part in a hundred thousand million million, it would have recollapsed before it reached its present size. On the other hand, if it had been greater by a part in a million, the universe would have expanded too rapidly for stars and planets to form.

The Big Bang theory is the idea that if we go back early enough in the history of the universe - and we can do this, of course, by looking at starlight coming to us from billions of years ago - we will see a very hot and dense period where the universe was much smaller, denser, and hotter.

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

We've known for a long time that the universe is expanding. But about 15 years ago, my colleagues and I discovered that it is expanding faster and faster. That is, the universe is accelerating, and that was not expected, but it is now attributed to this mysterious stuff called dark energy which seems to make up about 70 percent of the universe.

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

First of all, the Big Bang wasn't very big. Second of all, there was no bang. Third, Big Bang Theory doesn't tell you what banged, when it banged, how it banged. It just said it did bang. So the Big Bang theory in some sense is a total misnomer.

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.

That's what Hubble can do for us. It can tell us whether the universe is expanding forever or if one day it's going to come back together.

Because there is a law such as gravity, the universe can and will create itself from nothing.

You might expect gravity would slow it down, but it's just expanding faster and faster.

There is nothing bigger or older than the universe.

There may be many Big Bangs that happened at various and far-flung locations, each creating its own swelling, spatial expanse, each creating a universe - our universe being the result of only one of those Big Bangs.

One of the most exciting things about dark energy is that it seems to live at the very nexus of two of our most successful theories of physics: quantum mechanics, which explains the physics of the small, and Einstein's Theory of General Relativity, which explains the physics of the large, including gravity.

There was no 'before' the beginning of our universe, because once upon a time there was no time.