category: physics
GALILEAN RELATIVITY 2
The principle of relativity was first enunciated by Galileo in 1632. Galileo's argument is clear and graphically put. Salviatus: Shut yourself up with some friend in the main cabin below decks on some large ship …
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The Postulates of Relativity and Their Implications 3
The most profound conceptual implication of special relativity is the change it has brought about in our perception of the nature of time. Relativity requires us to reject the notion of absolute time, which was …
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SPACE AND TIME IN CLASSICAL MECHANICS
SPACE AND TIME IN CLASSICAL MECHANICS BY ALBERT EINSTEIN
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THE DECAY OF MUONS 1
The question at issue concerns the half-life of muons in motion. According to Galilean relativity, the motion should have no effect on the probability of decay; moving muons should have the same half-life as muons …
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The Postulates of Relativity and Their Implications 2
Millikan's account paints a dramatic (and credible) picture. Yet in his own writings Einstein suggests that Michelson's experiment played at most a minor role in the genesis of special relativity.
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The Postulates of Relativity and Their Implications 1
Many physicists, including both Lorentz and Michelson, were reluctant to abandon the ether. Although Lorentz quickly accepted Einstein's relativity, he continued to maintain that a medium of some kind is needed as the carrier of …
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THE SYSTEM OF CO-ORDINATES BY ALBERT EINSTEIN
But we can free ourselves from both of these limitations without altering the nature of our specification of position. If, for instance, a cloud is hovering over Trafalgar Square, then we can determine its position …
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GALILEAN RELATIVITY 1
Special relativity implies that moving clocks run slow. That is itself a strange result, but clocks running backward would be too much to swallow. No such disaster arises, however. In the case of the moths, …
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A HISTORICAL DIVERSION BY STEVEN WEINBERG 1
The writing history is largely a process of diversion, Most historical accounts distract attension from the secret influences behind great events.
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FIRST THREE MINUTES 1
We are now prepared to follow the course of cosmic evolution through its first three minutes. Events move much more swiftly at first than later, so it would not be useful to show pictures spaced …
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THE POSSIBILITY OF A “FINITE” AND YET “UNBOUNDED” UNIVERSE
In the first place, we imagine an existence in two-dimensional space. Flat beings with flat implements, and in particular flat rigid measuring-rods, are free to move in a plane. For them nothing exists outside of …
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COSMOLOGICAL DIFFICULTIES OF NEWTON’S THEORY
This conception is in itself not very satisfactory. It is still less satisfactory because it leads to the result that the light emitted by the stars and also individual stars of the stellar system are …
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Wisely, and slow. They stumble that run fast.
---William Shakespeare
Imagination is more important than knowledge.
Life is like riding a bicycle. To keep your balance you must keep moving.
If you can't explain it simply, you don't understand it well enough.
--- Albert Einstein