2.1 Making sense of the universe and its impact Flashcards
the influence of claudius ptolemy
What did Ptolemy produce?
- tables to track and predict the position of the sun, stars, and planets
the influence of claudius ptolemy
doubts?
- provided mathematical models without observed evidence
the influence of claudius ptolemy
what did Ptolemy suggest based on these models?
- hypothetical bodis such as extra planets and stars might exist in the solar system
- although there wasnt evidence fro this, this was the only system that seemd to work
the influence of claudius ptolemy
how did ptolemy’s view contrast aristotles?
- Aristotle: earth was the centre of everything and heavenly bodies moved in perfect circles around the earth
- Ptolemy: epicycles didnt move around the earth but haflway between the earth and another point called the equant
the influence of claudius ptolemy
Ptolemy and the continued development of the model of the universe: what was it by the late middle ages?
- Ptolemy could account for apparent changes in speed as the planets were in orbit but also maintain his system of perfect circles
- as the system was refined and the number o circles used by astronomers increased, it became so complex by the late middle ages it was unworkable
Nicolaus Copernicus
Background: when was he born? where did he excel? what did he become?
- born in poland in 1473
- excelled at the University of Krakow and became a polymath
- most significant field was astronomy
Nicholas Copernicus
his book De revolutionibus orbium coelestium (on the revolutions of heavenly spheres): what does it mark the beginning of?
-
- the beginning of the scientific revolution for most people
- 30 years of research
- dedicates the book to Pope Paul III
Nicholas Copernicus
what did he propose the universe was? who did this oppose?
- the universe was heliocentric, which meant the sun was at its centre
- this opposed Ptolemys beliefs
Nicholas Copernicus
What was Copernicus’ theory?
- agreed with Aristotle and Ptolemy that heavenly bodies moved in perfect circles, but proposed the universe was made up of 8 years
- sun was at the centre of the 8 but it didn’t move
Nicholas Copernicus
what did Copernicus have to present his work as?
- Platonic theory rather than Aristotelian fact.
Nicholas Copernicus
1616 catholic church
- banned the book
- wasn’t removed from the index until 1758
- scholars could access an edited version
- became very influential after his death
The limits of Copernicus’ findings
3 main limits
THEO, SPHE, PERF
- made theoretical conclusions rather than empirical observations
- continued to believe planets and stars moved on spheres but he was not sure what these spheres were made of
- kept Ptolemy’s underlying approach that planetary movements were perfectly circular
The limits of Copernicus’ findings
however, what did people believe about Copernicus findings?
- they were theoretical, and his thoughts were not taken seriously. It was counter-intuitive and impossible, and it contradicted the bible.
The limits of Copernicus’ findings
what was Andreas Osianders role?
- protestant minister
- stated the book served simply as a model to aid stronomical calculations, and Copernicus’ findings were unlikely to be accurate.
the impact of Johannes Kepler (the influence of Tycho Brahe)
1600 Kepler and Brahe?
- Kepler began working for Danish astronomer Brahe in 1600
- Brahe became the imperial astronomer for the Holy Roman Emperor in 1597
the impact of Johannes Kepler (the influence of Tycho Brahe)
What did Brahe believe?
- planets circled the sun, but the sun also circled the earth, which was always stationary
the impact of Johannes Kepler (the influence of Tycho Brahe)
Brahe’s controversial beliefs: 1572 he observed what?
why was it controversial?
- a supernova
- published his findings
- went against Ptolemaic and Aristotelian opinion that the universe couldnt change
the impact of Johannes Kepler (the influence of Tycho Brahe)
1588 comets?
- he observed a number of comets and concluded they existed outside the atmosphere of earth rather than inside it
- the path taken meant the idea all heavenly bodies were controlled by perfect spheres was made redundant.
the impact of Johannes Kepler (the influence of Tycho Brahe)
What did Brahe believe about spheres?
- that planets moved independently through space, and didn’t follow exactly the same paths, so there was no need for spheres.
Keplers career
background and education
- 1577 he witnessed the Great Comet which was one of the three that Brahe had observed, and he became passionate about astronomy and mathematics
- studying at university he agreed with Copernicus theory of heliocentrality
- he began teaching in 1594
Keplers career
Mysterium Cosmographicum (cosmic mystery) 1596
what did he argue?
Keplers views on Copernicus and Ptolemy
- insisted the universe was perfectly designed by God
- Kepler adopted the heliocentric view of Copernicus but avoided reliance on Ptolemaic spheres and epicycles.
Keplers career
What was Keplers initial idea?
dimensional shapes
- complicated system
- 6 layers of 3 dimensional shapes nestled together and would correspond to the path of the 6 planets
he later rejected this
Kepler’s law of planetary motion
Kepler and Brahe’s patronage?
- Kepler moved to 1600 after being noticed by Brahe
- he assisted him with his research
- to secure Brahe’s patronage, Kepler wrote in defence of his theories and after his death, continued his work
Kepler’s law of planetary motion
1609 Astronomia Nova 2 laws of planetary motion?
orb, sped
- planets travel in elliptical orbits around the sun
- the speed of planets varies as they circle the sun, when a planet is closer, it moves faster, and vice versa
Kepler’s law of planetary motion
what type of approach did Kepler take?
- physical rather than theoretical based on his and Brahe’s observations
Kepler’s law of planetary motion
Keplers mother
- was accused of witchcraft in 1617 and was imprisoned in 1620, but after Keplers extensive defence was released in 1621
Kepler’s law of planetary motion
Keplers 3rd law (Harmonices Mundi)
- distances from a planet to the sun cubed, proportional to the time it takes for a planet to complete its orbit, squared
- the further the plant is from the sun, the slower its orbit
Kepler’s law of planetary motion
Keplers limits
- he didnt understand gravity properly, his theory wasnt taken any further utnil Isaac Newtons theroy of gravity developed.
Kepler and religion
what was the influence of religion on Keplers theory?
- Since God was all knowing, the universe he created would have been faultless mathematically.
- In Harmonices Mundi he elucidated that relationships between heavenly bodies were so perfect they had to be made by God.
- Newton refined Keplers third law
the impact of keplers theories
what was the impact of Keplers theories?
- the realisation that constant circular and linear motions were not always taking place in the universe
- questions raised about what caused planets to move if not invisible spheres
- Boundaires between philosophy and mathematics blurred as a result of Kepler’s work
Galileo Gallilei
Galileo background: university professor?
- he was expected to defer to the higher status natural natural philosophers, so was paid a lower wage
Galileo Gallilei
He recieved at title as philosopher at the court of…
- Cosimo de’ Medici, Duke of Tuscany
- he gained respect
Galileo’s life and influences
Education?
- born in 1564 and studied medicine from 1581
- left university without a degree
- 1589: he taught maths at Pisa University and in 1592 he was appointed professor of mathematics at Padua University
- In 1610 he was appointed to the court of the Duke of Tuscany
Galileo’s life and influences
Dialogue Concerning the Two Chief World Systems 1632
- written dialogue where 3 thinkers debate, and his theories come across refreshing and analytical
early controversy
his work Discourse on the Tides 1616, what did it argue? why was it controversial? how was the inquisition involved?
- he explains his belief that the tides were caused by the Earth speeding up and slowing down as it rotated on its own axis and orbited around the sun
- he debated with the catholic church
- he was held in suspicion by the inquisition for the next 20 years, sinceh is theory contradicted the bible
early controversy
what did Galileo reject?
Brahe’s theory that the plantes move around the sun and the sun moves around the stationary earth
early controversy
siderius nuncius 1610: what did Galileo identify?
4 main points? moon and motion, jupiter, stars.
- the moon had seas and mountains
- natural motion of the moon was circular around the earth
- jupiter has moons
- new stars exist, and there is not a finite number of fixed stars. (this supported copernicus’ idea that stars cannot be set on a fixed sphere but are spread throughout space)
early controversy
The Assayer 1623: what did Galileo argue?
- the study of the universe should be balanced between maths and experiment
early controversy
how and why did the church take issue with his work
- index liborum prohibitorum
- they took issue with his work on tides and sunspots
Dialogue Concerning Two Chief World Systems 1632 was banned along with his other books as it contradictd the church sponsored Aristotelian system
early controversy
how did the church punish Galileo?
- he was made to sign a recanting statement and was placed under house arrest
- he was found guilty of heresy
- the ban on printing all of Galileo’s work wasn’t lifted until 1758
- some of his work was unbanned in 1718, even in 1758, Dialogue was still advised to be censored
publication of Dialogue Concerning the Two Chief World Systems 1632
how did Galileo see himself?
- the heir to aristotle logical approach and the views’ copernicus regarding the makeup of the univrese, agreeing that the sun was at the centrer of the solar syste,
Structure of the Dialogue
structure:
what are the 3 thinkers names?
- Salviati
- Simplico
- Sagredo
Structure of the Dialogue
Salviati: how does he speak?
- gives galileo’s views
- he attacks the aristotlian view that hte universe cannot change
- he argues its ridiculous to suggest the earth doesn’t rotate and move like other planets
Structure of the Dialogue
Simplico: what does he advocate for?
- advocates for Ptolemaic system, and argues against the Copernican model
- he argued if the earth was rotating, a canonball fired to the west would travel much further than one fired east
Structure of the Dialogue
Sagredo: who was he?
- neutral, ordinary man
- not a philosopher
Structure of the Dialogue
how did he disagree with Aristotle? what did he exclaim instead in terms of motion
- aristotle said everything that moves must be pushed
- galileo disagreed, and said if a ball was set in motion on an endless and frictionless incline, it would go on forever. IF it encountered an upward slope it would slow down
Structure of the Dialogue
if there was a perfectly horizontal plane…
once the ball was in motion it would continue forver constnantly
- this ignored Keplers belief in elliptical motion
Structure of the Dialogue
How did Galileo also try to build Aristotle’s theory of motion?
- he refined Aristotle’s theory that bodies fall with speeds proportional to their weight
- he proposed acceleration and speed in freefall is constnat for all bodies
Structure of the Dialogue
how did he come very close to the theory of gravity? what did he suggest?
- he proposed a ball dropped off a tower wouldn’t fall to the west of the tower as the rotating earth moves eastwards
- he proposed all things on earth moved in a rotating motion, rather than gravity
The impact of Galileo
How did Galileo disobey the church?
- they told him not to defend copernican theory, but he did so anyway with minor adjustments.
- he rejected the right of the church to act authorative over scientific matters
The impact of Galileo
what did Pope Urban VIII protest after his death in 1642
against a plan by the Duke of Tuscany to give Galileo a ceremonial burial
The impact of Galileo
what was his biggest achievement?
developing a mathematical approach to the study of natural phenomena
- Galileo relied on empircism and observation
galileo galilei
How was he different from Kepler?
Kepler was interested in mysticism and godly explamnations for events whereas Galileo wasn’t interested in superstition and relied on empircism
Isaac Newton
first letters to the royal society concerned what?
- light and his new reflective telescope (1672)
isaac newton
1687 work title
Philosophiae Naturalis Principia Mathematica
isaac newton
who did he build on?
kepler and his laws of motions
newtons forerunners: descartes and huygens
Descartes: his work and what it meant
+ was he condemned
1653: the world fused together mathematics and natural philosophy when he explained mathetmatically the events of the universe.
- although, he withdrew this due to fears of being condemned by the inquisition
newtons forerunners: descartes and huygens
Christiaan Huygens: influence on Newton
- his work on motion and gravity influenced Newton the most
- in the 1650s and 1660s his research on motion led him to propose a law very similiar to Newtons second law of motion
- publishe 14 years before Principia Mathematica(
Newton’s career
education
- trinity college cambridge 1661
- taught as Lucasian Professor of Mathematics in 1669 until 1696
newtons career
MP for cambridge: why?
- elected in the convention parliament of 1689 because he resisted James II’s attempts to turn universities into catholic instututions.
- he was elected again in 1701
newtons career
royal society member? presidnet?
1672
- became presidejnt in 1703
- he was re elected each year until he died in 1727
newtons career
principia mathematica other theories? Kepler’s laws?
- Kepler’s laws of planetary motion could be proven mathematically
newtons career
Principia Mathematica other theories made?
AR, CF,X AC
- questioned aristotle’s view that the earth worked differntly from the rest of trhe universe
- newton was able to adequately explain Centrifugal force
- Newton’s theory of acoustics, where sound is based on the density of the medium it passes through
newtons career
newtons 1st law
- every object will remain in a straight line unless an external force makes it change direction
Newtons career
newtons 2nd law
the external force on an object is equal to the mass of the object x the rate of acceleration
newtons career
newtons 3rd law
every action has an equal and opposite reaction
newtons career
in contrast to keplers argument, what did Newton show planets are being pulled by?
- kepler argued plants have a force behind them pushing them into orbit
- newton countered this, arguing instead planets are pulled by the gravitty of the sun
- the natural path forms a circular orbit because of gravity
the impact of newtons theories
what does newtons work represent?
the final stage of theory and discovery evolving for over 100 years
- his work wasn’t accessible to many due to its publication in Latin, interpreters such as Volitare provided simpler versions of his work for the masses
- historians judege NNewton completed the ‘mathematisation’ of natural philosophy because in his work there were no grey areas
Newton and magic
How was Newton shown to believe in the power of magic?
- in early drafts of Principia Mathematica he propoed gravity was the result of magic
- he was also obsessed with the significance of the number 8
newton and magic
newtons belief in cosmic harmonies?
followd Keplers belief of a harmonious universe, where God created 6 ploanets that fit in a perfect geometric plan
newton and magic
Newton as an alchemist?
- he believed different particles could be attracted to eachother across an empty space, and his confidence in the power of light and gravity stems from the idea that supernatural forces were resposible
newton and magic
newton and the Bible?
- his study of the bible was as dedicated as his scientific study
- he wrestle with prohecies he thought could be found in the books of Daniel and of Revelation from a young age until he died
- later, he wrote down supposed hidden messages he found, including speculation about when the world would end.
