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Ides of May is Kepler Day

  1. May 12, 2006 #1


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    Kepler is the patron saint of quantum gravity and 15 May was the day Kepler had a really new idea which he called "sesquipotentia" or "one and a half power" law.

    He recorded in his diary that the idea had occurred to him on 8 March but he dismissed it, thinking it was wrong, and then on 15 May it "returned and stormed the darkness of my mind".

    I suppose that whenever science is done it is done with the understanding that this kind of thing can happen----something can suddenly appear and storm the darkness of your mind.

    If you happen to be needing a really new idea then maybe it would not hurt to pray to Kepler, as one may, to saints. Or light a candle. Or drink a toast of favorite beverage. Or do whatever it is that one does.

    I suspect theoretical physicists nowadays do need a really new idea, or several of them. Maybe they have already thought all the new ideas they need right now and merely havent noticed----so the ideas are hanging out and waiting for some time when they will return and storm the darkness of the theoretians' minds. But in any case some of them SAY they need a really new idea. Like David Gross did famously not long ago. And in that case it might not hurt to pray to Kepler.

    He worked hard on it and got some extremely new ones. Like spacetime was constructed of ovals instead of transparent spheres with circular tracks around the middle. People are always wondering what spacetime is constructed of. Nested Platonic solids, whatever. Spin networks. heh heh.

    I intend to drink a beverage in honor of Kepler on the 15th and to reflect on the fact that we do every now and then need a really new idea.
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  3. May 12, 2006 #2


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    Oriti's book keeps changing its title. Last time i saw it mentioned it was "Towards a new understanding of space, time, and matter"

    They really seem to need a fresh VISUALIZATION of space and time, and how bits of matter arise in it and sit in it and interconnect with the geometry of it.

    Yeats said about Blake:
    Or that William Blake, who beat upon the wall
    till truth obeyed his call.

    Kepler beat his head against the wall of calculating planet positions tediously by hand over and over, until he found a new way to visualize it. He changed what spacetime was made of---in the human imagination.


    Maybe the beverage will be lemonade from Meyer lemons off our tree. I am thinking of the child next door. You have to say the "sesquipotentia"---the "three-halves-power law" very gently

    If there were a planet 4 times farther from the sun than us, its orbit would take 8 years.

    If there were a planet 9 times farther from sun than us, it would take 27 years.


    Archimedes knew about squares and cubes and areas and surfaces and knew lots of proportions but probably didnt ever get to a proportion between distance and time, or to a proportion involving a three-halves power instead of just an integral power. So that was part of the newness of Kepler.

    I think the year, for that third one, was 1618-----a year mostly remembered because some people got pushed out a window (they werent hurt either, fortunately enough, but landed somewhere soft like in a moat or dungheap)

    the Yeats poem is called An Acre of Grass
    Last edited: May 12, 2006
  4. May 12, 2006 #3


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    Modern scholars working with Kepler's private papers have concluded that the tale he tells in Astronomia Nova of his discovery of the equal areas law, the 70 iterations and the humble stance toward Tycho's wonderful data, is cleaned up and partly fictional. The 70 iterations came because he had trouble finding a good opposition to check his results. That is to say it was a data problem.

    But Kepler didn't want to say that because Tycho's groundbreaking observational accomplishments were the ground that he cited in support of his new astronomy, and he didn't want to call them into question.
  5. May 13, 2006 #4


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    that's interesting.
    I went back and found some quotes


    I still havent come across the place where he says he first thought of the 3rd Law on 8 March 1618 but dismissed it and then on 15 May he says it returned and "stormed the darkness of my mind"
    the combined posture of grandiosity and humility has always delighted me. and maybe that is what a great idea does.

    maybe I will find that quote later. We decided to have some friends over on Monday to drink a toast to old Kepler and eat a cookie.
  6. May 13, 2006 #5


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    here is that quote, I found it on the web

    On how he discovered his Third law:
    "...and if you want the exact moment in time, it was conceived mentally on 8th March in this year one thousand six hundred an eighteen, but submitted to calculation in an unlucky way, and therefore rejected as false, and finally returning on the 15th of May and adopting a new line of attack, stormed the darkness of my mind. So strong was the support from the combination of my labor of seventeen years on the observations of Brahe and the present study, which conspired together, that at first I believed I was dreaming, and assuming my conclusion among my basic premises. But it is absolutely certain and exact that the proportion between the periodic times of any two planets is precisely the sesquialterate proportion of their mean distances ..."
    Harmonice mundi (Linz, 1619) Book 5, Chapter 3, trans. Aiton, Duncan and Field, p. 411.


    here the translator says "sequialterate" but I looked at the Latin original of the introduction one time and saw him using "sequipotentia" or "sesquipotence" for the 1.5 power. He doesnt always say it the same way but he seems often to use the prefix "sesqui" in this context
  7. May 13, 2006 #6

    I take a look at Kuhn's The Copernican Revolution...

    Kepler's faith in simple mathematic laws of Nature gave us the Armonic Law, but he also produced a lot of laws that are armonic but not experimentally congruent (he didn't care about datas at all times)... it would be a warning!

    well, I have a genuine platonic/pytagoric feeling, but this is faith, not science... but if we admit that everybody who do science has some kind of faith, the most honest thing to do is to explicit it...

  8. May 13, 2006 #7


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    but Kepler should not be a role model

    he was a PRE-scientist
    (also Newton believed crazy things)

    these were complicated people, living before there was a clear ideal of how to be a scientist.
    their lives can show us some examples of what to do, but also
    some clear examples of what NOT to do.

    I feel like celebrating Kepler as a man or human being, not as an ideal scientist. When I read his biography (for example the one by Arthur Koestler) I sometimes have to laugh, also sometimes feel sorry for him.
    he was far from perfect. but he was great.
  9. May 15, 2006 #8


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    Hallmark Greeting Card On Kepler Day

    [Nature, the universe] is a blossoming or dancing where
    The body is not bruised to pleasure soul.
    Nor beauty born out of its own despair,
    Nor blear-eyed wisdom out of midnight oil.
    O chestnut-tree, great-rooted blossomer,
    Are you the leaf, the blossom or the bole?
    O body swayed to music, O brightening glance,
    How can we know the dancer from the dance?

    (adapted from a Yeats poem, he said Labour, but the Latin root of Nature is birth, nature means birthing or what is born. I decided the poem would work about nature and the universe)

    Best wishes and regards to everybody here on this Kepler Day of 2006.

    Kepler and people like that DO burn the midnight oil so that someday the patterns of the universe will come easily to our minds. and everyone will be able to see that the laws are beautiful

    they do the frustrating work for us, of discovering the patterns

    the tree is a dance of atoms, the dancer is a dance of atoms,
    how can we know the laws from what obeys the laws
    or the pattern from what follows according to it

    in America it is traditional on holidays to send a Hallmark card, these are cheap greeting cards usually with sentimental rhyming verses on them and pictures of flowers or cats
    you have now received a Kepler day Hallmark card
    Last edited: May 15, 2006
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