Nuclear Particle Quotes (2)

Consideration of particle emission from black holes would seem to suggest that God not only plays dice, but also sometimes throws them where they cannot be seen.
'The Quantum Mechanics of Black Holes', Scientific American, 1977, 236, 40.
See also:  |  Black Hole (3)  |  God (51)

There are something like ten million million million million million million million million million million million million million million (1 with eighty zeroes after it) particles in the region of the universe that we can observe. Where did they all come from? The answer is that, in quantum theory, particles can be created out of energy in the form of particle/antiparticle pairs. But that just raises the question of where the energy came from. The answer is that the total energy of the universe is exactly zero. The matter in the universe is made out of positive energy. However, the matter is all attracting itself by gravity. Two pieces of matter that are close to each other have less energy than the same two pieces a long way apart, because you have to expend energy to separate them against the gravitational force that is pulling them together. Thus, in a sense, the gravitational field has negative energy. In the case of a universe that is approximately uniform in space, one can show that this negative gravitational energy exactly cancels the positive energy represented by the matter. So the total energy of the universe is zero.
A Brief History of Time: From the Big Bang to Black Holes (1988), 129.
See also:  |  Energy (16)  |  Gravity (22)  |  Matter (29)  |  Universe (57)

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Original words on great scientific discoveries.
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I have little patience with scientists who take a board of wood, look for its thinnest part and drill a great number of holes where drilling is easy. --Albert Einstein
I try to identify myself with the atoms...I ask what I would do if I were a carbon atom or a sodium atom. --Linus Pauling




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