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Why do the laws that govern [the universe] seem constant in time? One can imagine a Universe in which laws are not truly law-full. Talk of miracle does just this, invoking God to make things work. Physics aims to find the laws instead, and hopes that they will be uniquely constrained, as when Einstein wondered whether…
Davy’s two main essays were far the most ambitious contribution to the anthology, and announced his intellectual arrival in Bristol. He set out to champion chemistry, and speculate about its future, on the grandest metaphysical scale. In a Penzance notebook he had exclaimed: ‘What we mean by Nature is a series of…
Already in a paper of 1802 Herschel considered the idea that ‘deep space’ must also imply ‘deep time’. He wrote in his Preface: A telescope with a power of penetrating into space, like my 40 foot one, has also, as it may be called, a power of penetrating into time past … [from a remote nebula] the rays of light which…
In fact, our own universe is very likely itself a vast black hole. We have no knowledge of what lies outside our universe. This is true by definition, but also because of the properties of black holes. Objects that reside in them cannot ordinarily leave them. In a strange sense, our universe may be filled with objects…
We conclude that there cannot be a strongly cohesive network of communicating, unifying intelligences through the whole universe if (1) such galactic civilizations evolve upward from individual planetary societies and if (2) the velocity of light is indeed a fixed limit on the speed of information transmission, as…
If one assumes that a few hundred million years in stable orbit are necessary for planetary life to evolve, the number of space dimensions is also fixed by our existence. That is because, according to the laws of gravity, it is only in three dimensions that stable elliptical orbits are possible. Circular orbits are…
If the total energy of the universe must always remain zero, and it costs energy to create a body, how can a whole universe be created from nothing. That is why there must be a law like gravity. Because gravity is attractive, gravitational energy is negative: One has to do work to separate a gravitationally bound…
That the universe is expanding was news to Einstein. But the possibility that the galaxies are moving away from each other had been proposed a few years before Hubble's papers on theoretical grounds arising from Einstein's own equations. In 1922, Russian physicist and mathematician Alexander Friedmann investigated…
Whether M-theory exists as a single formulation or only as a network, we do know some of its properties. First, M-theory has eleven space-time dimensions, not ten. String theorists had long suspected that the prediction often dimensions might have to be adjusted, and recent work showed that one dimension had indeed…
While conceding that human behavior is indeed determined by the laws of nature, it also seems reasonable to conclude that the outcome is determined in such a complicated way and with so many variables as to make it impossible in practice to predict. For that one would need a knowledge of the initial state of each of…
If you believe the cosmos is made up of omelette, you build instruments specifically designed to find traces of intergalactic yolk. In that paradigm you reject phenomena like pulsars and black holes as paranormal garbage. In an omelette cosmos, the beginning of the universe becomes a chicken and egg problem, doesn’t…
Metaphysically speaking, no one paradigm is innately any better than any other. A universe that began at 9 a.m. on October 10, 4004 B.C. (which was official back in the seventeenth century) is intrinsically no less valuable for those who live by a belief in it than is our present uncertain universe, perhaps built like…
What gravity is and why it is, no one knows. Albert Einstein spent most of his life trying to figure it out, but the secret eluded him. it is simply a fact that everything in the universe with mass pulls on everything else. If it weren't for the initial outward impetus of the Big Bang, gravity would have caused the…
Every point mass attracts every single other point mass by a force pointing along the line intersecting both points. The force is proportional to the product of the two masses and inversely proportional to the square of the distance between them
The relative interattractiveness invisibly operative between any two remote-from-one-another cosmic bodies, as compared to any other pair of cosmic bodies, equally distanced from one another, is proportional to the multiplicative product of the respective couple's masses, and the interattractiveness of any pair of…
To ANYONE who has been in space and experienced its changelessness, the real excitement of space flight comes when it is time to land on a new planet. The ground speeds backward under you as you catch glimpses of land and water, of geometrical areas and lines that might represent fields and roads. You become aware of…
The fact of our own existence is almost too surprising to bear. So is the fact that we are surrounded by a rich ecosystem of animals that more or less closely resemble us, by plants that resemble us a little less and on which we ultimately depend for our nourishment, and by bacteria that resemble our remoter ancestors…
As I've tried to stress, at the heart of science is an essential balance between two seemingly contradictory attitudes - an openness to new ideas, no matter how bizarre or counterintuitive, and the most ruthlessly sceptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense…
...the order of the Universe is not an assumption; it's an observed fact. We detect the light from distant quasars only because the laws of electromagnetism are the same ten billion light years away as here. The spectra of those quasars are recognizable only because the same chemical elements are present there as…
The chessboard is the world; the pieces are the phenomena of the universe; the rules of the game are what we call the laws of Nature. The player on the other side is hidden from us. We know that his play is always fair, just, and patient. But also we know. to our cost, that he never overlooks a mistake or makes the…