category: physics
GRAVITATIONAL FIELD
If now, as we find from experience, the acceleration is to be independent of the nature and the condition of the body and always the same for a given gravitational field, then the ratio of …
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SPECIAL AND GENERAL PRINCIPLE OF RELATIVITY
Since the introduction of the special principle of relativity has been justified, every intellect which strives after generalization must feel the temptation to venture the step towards the general principle of relativity.
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MINKOWSKI’S FOUR-DIMENSIONAL SPACE
The four-dimensional mode of consideration of the “world” is natural on the theory of relativity, since according to this theory time is robbed of its independence. Moreover, according to this equation the time difference ∆t' …
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THE RELATIVITY OF SIMULTANEITY
Events which are simultaneous with reference to the embankment are not simultaneous with respect to the train, and vice versa (relativity of simultaneity). Every reference-body (co-ordinate system) has its own particular time; unless we are …
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ON THE IDEA OF TIME IN PHYSICS
After some time perhaps the following answer would occur to you: “The significance of the statement is clear in itself and needs no further explanation; of course it would require some consideration if I were …
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THE MICHELSON-MORLEY EXPERIMENT
In a wave phenomenon that involves a medium, the rest frame of the medium is a unique frame of reference. Observers in any frame can carry out experiments to determine their velocity relative to the …
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THE FIRST ONE-HUNDREDTH SECOND BY STEVEN WEINBERG 3
So far our imagination carried us back to a temperature of 5,000 million million degrees, and we have had to deal with the strong, weak, and electromagnetic interactions. What about the one other grand class …
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THE FIRST ONE-HUNDREDTH SECOND BY STEVEN WEINBERG 2
These rather intuitive ideas have recently been put on a much firmer mathematical foundation. In 1973 it was shown by three young theorists, Hugh David Politzer of Harvard and David Gross and Frank Wilczek of …
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THE FIRST ONE-HUNDREDTH SECOND BY STEVEN WEINBERG 1
Naturally, it is tempting to try to peek behind this veil. The temptation is particularly strong for theorists like myself, whose work has been much more in elementary particle physics than in astrophysics. Many of …
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THE COSMIC MICROWAVE RADIATION BACKGROUND 2
The one piece of numerical data that was available to Penzias and Wilson was the intensity of the radio noise they had observed. In describing this intensity they used a language that is common among …
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THE COSMIC MICROWAVE RADIATION BACKGROUND 1
Now we come to a different kind of astronomy, to a story that could not have been told a decade ago. We will be dealing not with observations of light emitted in the last few …
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THE PRINCIPLE OF RELATIVITY (IN THE RESTRICTED SENSE)
THE PRINCIPLE OF RELATIVITY (IN THE RESTRICTED SENSE) BY ALBERT EINSTEIN
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Wisely, and slow. They stumble that run fast.
---William Shakespeare
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---Malala Yousafzai