Something pretty mysterious had to give rise to the origin of the universe.
If I take the theory as we have it now, literally, I would conclude that extra dimensions really exist. They're part of nature. We don't really know how big they are yet, but we hope to explore that in various ways.
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.
It's part of the shape of the Universe. I only have to talk to somebody and they begin to hate me.
We said that with initial LIGO, detections would be possible, and with Advanced LIGO, detections would be probable.
Gravitational waves will bring us exquisitely accurate maps of black holes - maps of their space-time. Those maps will make it crystal clear whether or not what we're dealing with are black holes as described by general relativity.
I think it's amazing that the entire community of astronomy has done what it's done. We've been able to deduce the nature of time and space and where we all came from. It's the most amazing detective story in history.
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.
If string theory is right, the microscopic fabric of our universe is a richly intertwined multidimensional labyrinth within which the strings of the universe endlessly twist and vibrate, rhythmically beating out the laws of the cosmos.
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.
Astronomers ought to be able to ask fundamental questions without accelerators.
Black holes can bang against space-time as mallets on a drum and have a very characteristic song.
I don't pretend to be an astrophysicist or anything, even though I do read about certain things like metaphysics and cosmology that I've always just been really interested in. I don't pretend to be able to sit down and pontificate on any of these subjects.
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.
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.
The fact that people can predict gravity wave sources that are within shouting distance makes me feel incredibly confident. Compared to monopoles, these sources are not just optimistic thinking.
Physicists must feel they are in the most exciting field in the world. Their minds must be afire.
Einstein's gravitational theory, which is said to be the greatest single achievement of theoretical physics, resulted in beautiful relations connecting gravitational phenomena with the geometry of space; this was an exciting idea.
The theory has to be interpreted that extra dimensions beyond the ordinary four dimensions the three spatial dimensions plus time are sufficiently small that they haven't been observed yet.
It is almost impossible to have a baseless snobbish opinion of the General Theory of Relativity.
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.
We can trace things back to the earlier stages of the Big Bang, but we still don't know what banged and why it banged. That's a challenge for 21st-century science.
In 1959 the University recognized our work by appointing me to a new Chair of Radio Astronomy.
The idea of combining the physics of modern particle theory with cosmology was very young when I started working on 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.
