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As to your first query, it seems to me that if the matter of our sun and planets and all the matter of the universe were evenly scattered throughout all the heavens, and every particle had an innate gravity toward all the rest, and the whole space throughout which this matter was scattered was but finite, the matter…
The idea that space and time can be curved or warped is fairly recent. For more than 2,000 years the axioms of Euclidean geometry were considered to be selfevident. As those of you who were forced to learn geometry at school may remember, one of the consequences of these axioms is that the angles ot a triangle add up…
As an example of the power of the Anthropic Principle, consider the number of directions in space. It is a matter of common experience that we live in three-dimensional space. That is to say, we can represent the position of a point in space by three numbers. For example, latitude. longitude and height above sea…
The great mystery at the heart of the Big Bang is to explain how an entire, fantastically enormous universe of space and energy can materiahse out of nothing. The secret lies in one of the strangest facts about our cosmos. The laws of physics demand the existence of something called "negative energy." To help you get…
ABOUT 13.5 BILLION YEARS AGO, MATTER, energy, time and space came into being in what is known as the Big Bang. The story of these fundamental features of our universe is called physics. About 300,000 years after their appearance, matter and energy started to coalesce into complex structures, called atoms, which then…
We can measure the influence of this thing we call dark energy, which is forcing an acceleration of the expanding universe. We don't know what that is, we don't know anything about it, other than what it's doing to the universe. Then 85 percent of the gravity of the universe has a point of origin about which we know…
Your Earth is a very small part of a very large industry. ... In your world, people are used to fighting for resources, like oil, minerals, or land. When you have access to the vastness of space, you realize that there's only one resource worth fighting over--even killing for--more time. Time is the singlemost…
After waiting patiently for the noise to subside, one of the male Red Guards turned to the victim. “Ye Zhetai, you are an expert in mechanics. You should see how strong the great unified force you’re resisting is. To remain so stubborn will lead only to your death! Today, we will continue the agenda from the last…
The cosmic perspective comes from the frontiers of science, yet it's not solely the province of the scientist. The cosmic perspective belongs to everyone. The cosmic perspective is humble. The cosmic perspective is spiritual—even redemptive—but not religious. The cosmic perspective enables us to grasp, in the same…
"Well," Bayta's eyes misted with thought as she curled her bare toes into the white softness of the rug and nestled her little chin in one plump hand, "it seems to me that the whole essence of Seldon's plan was to create a world better than the ancient one of the Galactic Empire. It was failing apart, that world…
‘The achievement of the Kaminari-zoku implies that there are other spacetimes. Certainly other regions of the Universe beyond our causal horizon. If rational actors have evolved in them, they will have broken their Planck locks – or worse, evolved natively in an environment with no restrictions on computational…
‘Duh huh! That’s putting it mildly!’ Zinda purses her lips. ‘There are two problems, really. The first is that we can’t solve any hard problems. Not really. Anything that’s NP-complete. The Travelling Salesman. Pac-Man. They are all the same. All too hard. Even if we had a computer the size of the Universe! It drives…
‘I talked to a woman of the Kaminari once,’ he says, ‘before the Spike. Don’t give me such a look, it wasn’t like that, we were just friends. But one night on Ganymede, we got philosophical. The Universe is a game, she said. It makes us into players. We can’t see the moves that are not allowed. Like in chess. There is…
My own field of physics is passing today through a phase of exuberant freedom, a phase of passionate prodigality. Sometimes as I listen to the conversation of my young colleagues at Princeton, I feel as if I am lost in a rain forest, with insects and birds and flowers growing all around me in intricate profusion…
If, on the other hand, we live in an open universe, infinite in space and time and continuing to expand into a future without end, then life has to face a prospect of slow freezing {111} rather than quick frying. The universe grows constantly colder as it expands, and the supply of free energy is constantly dwindling…
This is often the way it is in physics. Our mistake is not that we take our theories too seriously, but that we do not take them seriously enough. It is always hard to realize that these numbers and equations we play with at our desks have something to do with the real world. Even worse, there often seems to be a…
The discoveries of recent decades in particle physics have led us to place great emphasis on the concept of broken symmetry. The development of the universe from its earliest beginnings is regarded as a succession of symmetry-breakings. As it emerges from the moment of creation in the Big Bang, the universe is…
awking has written down an equation which looks rather like Planck's equation. Hawking's equation is S = kA, where S is the entropy of a black hole, A is the area of its surface, and k is a constant which I call Hawking's constant. Entropy means roughly the same thing as the heat capacity of an object. It is measured…
He talked to us about the new theory of black holes which he had then just worked out. The idea of a black hole was one of the most dramatic consequences of Einstein's theory of gravity. According to Einstein's equations, a massive star at the end of its life, when it has exhausted its nuclear fuel, continues to…
He talked to us about the new theory of black holes which he had then just worked out. The idea of a black hole was one of the most dramatic consequences of Einsteins theory of gravity. According to Einstein's equations, a massive star at the end of its life, when it has exhausted its nuclear fuel, continues to…