Beauty what beauty? Beauty Seminar, 3/16/04 – Al Albano

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Transcript of Beauty what beauty? Beauty Seminar, 3/16/04 – Al Albano

  • Slide 1
  • Beauty what beauty? Beauty Seminar, 3/16/04 Al Albano
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  • theres visual impact
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  • Cartwheel Galaxy
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  • Eagle Nebula
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  • Eskimo nebula
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  • Tesselation of the triangle group
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  • then, theres the beauty of a physical theory
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  • A theory with mathematical beauty is more likely to be correct than an ugly one that fits some experimental data Dirac
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  • What makes a theory beautiful? A historical example: the motions of heavenly bodies.
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  • Circumpolar stars seen from Yellowstone Park It started with the ancients
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  • From Peter Apian, Cosmographia (1524) An earth-centered universe
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  • Retrograde motion of Mars A problem
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  • A solution epicycles Mars moves on a circle, the epicycle, whose center moves on another circle, the deferent. There is a point inside the deferent, called the equant, not necessarily at the center of the deferent, such that the line from the equant to the center of the epicycle rotates with constant speed. The earth is located on the same diameter as the equant, but not necessarily at the center of the deferent Check out http://www.jimloy.com/cindy/ptolemy.htm deferent epicycle Mars Earth
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  • If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. Alfonso the Wise King of Castille (13 th c.)
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  • It must be simple.
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  • Enter Copernicus
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  • A sun-centered universe. But its still all circles
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  • Close but not quite right. Brahe
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  • Kepler says its ellipses
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  • Kepler describes the observations, but he does not explain anything.
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  • ditto for Galileo And they did not seem to realize that they were dealing with the same phenomenon.
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  • It must explain.
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  • Version 2: It must tell a story.
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  • Enter Newton Theres a force. Its the same force that makes apples fall, And tides rise, and holds galaxies Together.
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  • It must be universal.
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  • Version 2: It must explain more phenomena than those used to construct it.
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  • and it must be mathematically elegant.
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  • Nature and nature's laws lay hid in night, God said, "Let Newton be," and all was light. -- Alexander Pope
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  • Nature and nature's laws lay hid in night, God said, "Let Newton be," and all was light. -- Alexander Pope It did not last; the devil howling "Ho! Let Einstein be!" restored the status quo. -- Sir John Collings Squire
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  • Its not a force. Mass warps space and time. Apples and planets and galaxies Just move along paths Of least resistance.
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  • Mercury does not move on an ellipse; it moves on a rosette.
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  • Massive objects bend starlight
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  • Black holes exist Same size as solar system. Weighs as much as 1.2 billion suns!
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  • Problems: Einsteins theory does not work inside black holes. It does not work right after the big bang, either.
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  • Verdict: Einsteins story does not explain enough we dont have a beautiful theory yet.