Stephen Hawking Quotes

I am deeply impressed with the way dark matter has explained cosmological observations.

I've been working in cosmology since 1964.

The Planck satellite may detect the imprint of the gravitational waves predicted by inflation. This would be quantum gravity written across the sky.

Astronomers still can't decide what the shape of our universe is. Is it closed and finite, which is to say, is there a countable tally of all the galaxies that exist, even beyond the ones we can see? Or is it infinite? The latter possibility is still on the table.

I have always believed that astrophysics should be the extrapolation of laboratory physics, that we must begin from the present universe and work our way backward to progressively more remote and uncertain epochs.

Until the 1990s, there were few reliable observations about movement at the scale of the entire universe, which is the only scale dark energy effects. So dark energy could not be seen until we could measure things very, very far away.

Our galaxy, the Milky Way, is one of 50 or 100 billion other galaxies in the universe. And with every step, every window that modern astrophysics has opened to our mind, the person who wants to feel like they're the center of everything ends up shrinking.

One of the great challenges of modern cosmology is to discover what the geometry of the universe really is.

I would like to mention astrophysics; in this field, the strange properties of the pulsars and quasars, and perhaps also the gravitational waves, can be considered as a challenge.

The idea of combining the physics of modern particle theory with cosmology was very young when I started working on cosmology.

I'm a cosmologist. All I do is cosmology.

Gravitational waves, because they are so imperturbable - they go through everything - they will tell you the most information you can get about the earliest instants that go on in the universe.

The age of the universe is not just 'a guess', but rather it is a carefully measured number that is now known to a high degree of accuracy.

What was done is measure directly, with exquisitely sensitive instruments, gravitational waves predicted about 100 years ago by Albert Einstein. These waves are a new way to study the universe and are expected to have significant impact on astronomy and astrophysics in the years ahead.

The realization that baryonic matter is only a trace component of the universe revealed our understanding of the cosmos as shockingly incomplete and was one of the milestones that ushered in the era of modern cosmology.

It seemed like my favourite kind of job - a wonderful chance to ask something absolutely fundamental: the fate of the Universe and whether the Universe was infinite or not.

I always think of space-time as being the real substance of space, and the galaxies and the stars just like the foam on the ocean.

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.

From a scientific point of view, our mission is to seek answers to the fundamental questions about the universe. Many are open - we don't know about dark matter, which accounts for a quarter of the universe's matter, nor do we know why there's antimatter.

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.

A full understanding of what happens in our everyday lives needs to take into account what happened at the Big Bang. And not only is that intrinsically interesting and just kind of cool to think about, but it's also a mystery that is not given much attention by working scientists; it's a little bit underappreciated.

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.

Dark energy is incredibly strange, but actually it makes sense to me that it went unnoticed, because dark energy has no effect on daily life, or even inside our solar system.