Hecht
editMysterium: "either the souls of the planets are less active the farther removed a planet is from the sun or there exists only one motive soul in thje centre of orbtis, that is the sun, which drives the planet more vigorously the closer the planet is"
He was later careful to replace soul with force
immaterial force emanating from the sun
contradicting aristotle, he claimed that, rather than possessing a natural motion, a body resists motion and will resist attempts to move it. Planeets would stay in place regardless of any crystal spheres
he called it inertia. he didn't have the second part, that a body in motion would continue in a straight line- he believed a constnat force was needed
letter to fabricius
if a stone were placed behind the earth, of some noteworthy proportion of size, and the opportunity were given for both to be free from any other motion, then i assert that not only would it occur that the stone would move toward the arth, but taht the earth would move toward the stune
gravity is a amgnetic force that brings together similar objects which is of the same quantity in a lage or small body, and divided as per the mass of the bodies, and assumes the same extent as the body
two attracting bodies would divide the space between them in inverse ratio to their weights
two bodies would conme together at some intermediate place, each approaching the other at a distance proportional to the mass of the other
astronomia nova
the force of gravity is proportional to the masses of the interacting bodies, no one before Kepler had suggested such a thing
the earth moves towards a falling apple, though the distance is minute
if the earth would ceace to attract its sea water, it would rise up and flow toward the body of the moon
He even attempted to calculate how closely the Earth an dmoon would orbit each other if other forces were disallowed, thoguh he got the distance wrong because he assumed both were of the same density
outside the influence of a third body implies gravity falls with distance, though kepler did not explicitly say so
the spehere of influence of the attractive pwoer of the moon extends all the way to earth; it follows that the earth's power of attraction is likely to extend to the moon and far beyond and therefore that nothing that constst of anyextent whatsoever of tetrrestrial material carried up on hig can escaoe the grasp of this mighty power of attraction" - gravitational field strength
In the somnium,Kepler outlined the idea of centre of gravity and how an object placed there would remain motionless, but if moved slightly would head toward the gravity of the closest body
in note 202 of the somnium, kepler pointed out that sailors say tides are highest when the sun and moon are in syzygy. thus tides seem to be affectd by this same force
in the epitome of copernican astronomy, Kepler asserts that the planets are composed of material substance
https://www.degruyter.com/document/doi/10.1515/9781400831098.142/html?lang=en
Michel
editBorn filipo bruno. he took the name giordano upon joinging the mo9nestary
1573: ordained priest
1575: fled
legal procedings against him
he adopted Protestant aniconism, no saints n paintings (hate art?), relics
he had been told geneva was a home for heriticcs and freethinkers but soon found the calvinists juust as intolerant as the catholics
everable consistory antoine de la faye - bruno publishd a pamphlet contradicting him and he and the publisher were both imprisoned
he had to axcknowledge his guilt and grovel before the consistor, having every last copy burned
mnemotexchny was his specialty, and that for which he was most saught
giovanni mocenigo , patrician of venice, patron secrets of mnemontechny
he asked to go to frankfurt to oversee the printing of his works, moc refused because he wanted the serets to himself. when bruno prep-ared to go anyway, moc denounced him as a heretic
in prison within 24 hours brunio was interogated so thoroghly by the hol;y office that the records are his chief biographical source
perhaps yoyu have geater fear in passing sentence on me than i have in hearing it
he was execuited on the 17th february 1600
he loathed aristotle and spoke out against him, passioon both in friends and eenemies
in the number of woman, he had not rivalled king solomon, but at least had done his best
a man whom he had called almost divine, he then lambasted in a tretiese called the idiot triumphant
cain and abel, an upright manm a pythagorean in his non-killing of animals,l and that he was right to kill his brother
ca;vom l;itjermalncthon read purely out of curiosity i consider them more ignroant than myself
he was atracted to the darkness of the unknown the same way, as he haid, that a moth is attracted to a flame
he loathed mathemati8cs (possibly because he was bad at it) but considerd it an abstract persuit more suited to games than real life. He chastised archimedes for drawing circles when syracuse was falling
computational astronomy is merely an interpretation of translatiion of reality
i wish to see not with the eyes of ptolemy opr copernicus, but with my own
he was raised an aristotelian and even as he rejected him, used his terminology and several foundational principles
phiolosophers both ancient and modern had accepted heliocentrism but "he deduced that truth from other principles, his ery own, and more solid; thanks to which, not by authority but by sense and reason, he considers it as certain s anything can be"
To Bruno there was a point beyond which knowledge was impossible
god is unknowable in essence
you cannot arrive at the true nature of things by mere examination of phenomena
Adams
editmartyr to the new science and the new faith
dies a martyr and willingly
he uttered neither a sigh nor a groan when the cross is hel;d in front of him, he regards it for several seconds, fixedly, then averts his eyes
his ashes were then scattered to the four winds, and his books burned after him
bruno was born in 1548 in atown at the foot of mount visuvius
at 15 he entered to the dominican convent in naples
"who like stan the angel of pridem was the propogator of darkness and a bringer of intellectual anarchy"
"kif in the eyes of god there is but one starry globe, if the suna nd the moon and all creation are made for the doogd of the warth and the welfare of man, humanuity may be exalted but is niot the godhead abased? Is not this to traiten and confine his proefence>?What! Is the feeble human creatre th wsole object worthy of the care of god> No the earth is but a planet, the ranks hs e hiolds among the stars is by urupation,. It is time to dethrone her
russell
editFew references to his laws until his death in 1630
Ellipticality of orbits was accepted in France by 1645 and in Britian bgy 1655
the second law was accepted by 1645, but the third was initially ignored, because it had no solid theoretical basis
WEpitome of Copernican astronomy was probably the most widely read book on theoretical astronomy in nothern and western europe
Becayuse applying Keplers area law required tedious trial and error, many rejected it as an expression of the truth of the universe (Kepler problem two body problem newton)
Most of astronomica nova was just an account of |Kepler'as attempt to wrangle the orbit of mars. Only from page 284 out of 337 are the three laws mentioned
Galileo knew of Kepler's planetary theory, as one of his patrons had read astronomia nova, though he never mentioned it or accepted it.
Marmonices mundi was probably the least read of Kepler's works, with almost no references by later astronomers
teh rudolfine tables publishede in 1927 allowed people to test the laws against the data
logorithms and a lack of calculus made the tables difficult to use
the epitome was not read in kepler's lifetime
some accepted the elliptical reality but within a tychonic framework
Stephenson
edit1625 all protestants expelled- did not apply to Kepler as he was a court official
his library was placed under seal
seige of linz, starvation disease, peasant uprising
logorithms
Kepler: print in ulm
Ferdie: no in austria
peasants destroy printing press, nearly destroy manuscirpt
Kepler: now?
Ferdie: sure
river forzen no chance for a boat
left his family in the nearest town and brought his manuscript including the plates, up the frozen river on a wagon
kepler was too frail to travel to another printer
the rudolphine tabels were used by astrologers, astronomers, navigators for more than a century
kepler's death was mourned across europe
wife died at 47 2 of her children survived
ocuras hominum o quantum est in rebus inane- o the cares of man how is much of everything futile
Harmonices
editAs the universe was alive, it was simply the planets expelling dead material.
Francis Bacon's emphasis on experimentation, the expansion of scientific instruments and the replaement of geometry with algebra had weakened interest in Kepler's Platonic harmony
Man was made in the image of God, and thus thinks like god in contemplating the nature of the world, thus not all conjecture was false.
delayed publication to 1619 due to Kepler's work on the orbit of mars
1618: Diascovered third law of planetary motion
1635: Rudolfine tables based on Tycho's observations, including laws of planetary motion
Coperunicus was a postiori, Kepler beleived one could determine a priori from devining god's purpose
"transfer of the whole of astronomy from fictitious circles to natural causes"
Ramus: Produce a universe without equants or epicycles
true hypothesis based on astronomical observation (the planets slow down at apogee but accelerate at perigee) vs fictiious hypotheses (circles and equants used to describe it)
Timaeus, the world as an image of god
number magnitude and motions of the plaentary spheres= questions to answer
Timaeus: Both mechanical causes and divine causes should be considered
Pythagoras: 1+2+3+4 = 10 (perfect number) tetractys
Timaeus (attributed pythagoras) the soul of the world is divied into ratios based on the tetractys.
Kepler believed astrological effects to be due to the human soul responding to certain astronomical harmonies, just as it responds to music. It might determine a person's character, but it could never predict his future.
the aspects were the only things that should be retained from traditional astrology (constellations dumb)
star of bethlehem anyone? Supernova of 1604 occurred during a fiery trigon(great conjunction in fire signs)
Could the salad she had made for dinner have come together of its own accord
Kepler believed James I was a peacemaker who would unify Protestants and Catholics
presented a copy of de Stella Nova to james in 1606
James I critiqued astrology, which Kepler could of course explain away
Kepler believed that the Pythagoreans with the central fire and the counter earth (he believed to be the sun and moon) had presaged his own discoveries, but Aristotle had misinterpreted planets for elements
Water means Venus because liquids are subject to Venus, and she emerged from sea-foam
The human love of music was the image of God's love for the harmonies of the universe
Pythagoras and the smithy, with the hammers and sounds
Pythagoras tied consonance to proportion
With the observations of Tycho, Kepler found that his original plantonic solid model no longer fit
not the platonic solids alone.
Aristotle: tabula rasa; Kepler image of god (consonant dissonant instinct)
numeric ratios were not enough, geometry explains physical phenomena
The harmonic ratios should appear from the vantage point of the sun, the prime mover.
different planets perihelia and aphelia coincide at different tunings
If just as the Earth is moistened and gorws green with rains, the sun grows bright with these burning spots springing out from its body, which is wholly on fire, with its brighter flamelets? What use is this furnishing, if the globe is empty? Do not the very senses cry out that fiery bodies inhabit itwhich have the capacity for simple mindsand that in truth the sun is, if not the king, then at least the palace of the intellectual fire?
Ferguson
edit1612: Georg Brahe became executor, handed Kepler all of Tycho's observations
2, 3, 4, 5, 8 (constructable, knowable, consonant) 7, 9, 11 (unconstructable, unknowable, dissonant)
man was made in the image of god, what we find beautiful, he finds beautiful
Ferdinand II who had exiled Kepler from Graz, became ruler of the Holy Roman Empire.
Some of Kepler's friends had their tongues cut out, their bodies quartered, and their heads stuck on spikes.
Kepler was spared, though he temporarlily lost his library
In 1623 he lost another child, and in 1626 nearly lost the rudolfine tables when a peasant uprising burned down his printer's shop, but spared the manuscript.
In 1624, having recently discovered the newly invented logorithm, Kepler finally finished the rudolfine tables.
Astoundingly, he had to self-publish again, even though Tycho's heirs still held profit and censorship rights.
Ferdinand was reluctant to publish outside austria, but with the war nearly destroying the tables, he agreed. Kepler rode a wagon full of plates up a frozen river to Ulm, where the tables were finally published.
Matthias allowed Kepler to travel to Linz to assume the post of mathematician. He also allowed him to retain the post of imperial matheamtician and salary
twice rejected from Tibungen for his religious views
he took a second wife, Susanna, who would bear him six children, though three would die of smallpox
Matthais himself attended the wedding
fell behind on a mapmaking project, but the support of his patrons saved his job
"Permanent repentance about lost time, and permanent lost time due to my own fault. Although I am very industrious, I am the harshest hater of work. But I work for thirst of knoledge. I am never lacking an object of my desire my burning eagerness to do research on difficult matters.
The bible was written for people with no knowledge of science,
It would not be until Rene Descartes that anyone would demand physical causes for astronomical phenomena. Producing caldendars was "a little more honorable than begging"
Epitome, published between 1615 and 1621 in seven volumes intended for "the low schoolbenches"
15th of may 1618 discovers thrid harmonic law, Goes into "sacred frenzy"
1619: Fraui kepler 74 was thrown in a chest, and taken in chains
1620: Kepler and his family left Linz telling no one
Knight
editkepler was an animist, who believed all things were embued with soul
he believed in the cosmic harmony of god's design, and that man's ability to concieve of geometry was proof of it.
everything was tied to geometry and geometry was tied to music
kepler's third law (squares of orbital periods equal to the cube of the distance)
it essentially created the discipline of celestial mechanics
1623@ attempt to publish the rudolfine tabels, but ahd to sholder printing costs, while epense of travelling across germany to plead for money oweed him drained his finances
1625: once again, all protestant teachers were ordered to leave
kepler was still a court appointee, and the emperor wanted those tables
his prinjters house and press were destroyed by revolting peasants
somehow hs manuscript survived
He had the chance for a cushy, safe job under Ferdinand III, if he converted to Catholicism. He didnt
grave
editKepler did not die in anonymity. He was still the imperial mathematician, and many wealthy and powerful men walked in the funeral procession.
8. Kepler’s grave is unknown to this day Johannes Kepler passed away on November 15th, 1630 in Regensburg and was interred at the local cemetery. Unfortunately, the exact location of Kepler’s grave was lost for good during the Thirty Years’ War between Germany and Sweden.
I measured the heavens. Now the shadows of the earth I measure. Skybound my mind. Earthbound my body rests.
Johannes Kepler , who was buried in the former Protestant St. Peter's Cemetery. Like the entire Protestant St. Peter's Cemetery, his grave was destroyed in the Thirty Years' War in 1633 in the course of the preparations for the fighting for Regensburg. After the war, the Protestant cemetery was restored, but the location of the Kepler grave was not recorded and can therefore no longer be located today