TheThe

ScientificScientific

RevolutionRevolution

• In the 1500s and 1600s the Scientific Revolution changed the way Europeans looked at the world.

• People began to make conclusions based on experimentation and observation, instead of merely accepting traditional ideas.

The Scientific Revolution

• Until the mid 1500’s, European scholars accepted and believed the teachings of Ptolemy, an ancient Greek astronomer.

• Ptolemy taught that the Earth was the center of the universe.

Ptolemy(87-140 A.D.)

Before the Scientific Revolution…

• It was not until some startling discoveries caused Europeans to change the way they viewed the physical world.

•People felt this was common sense, and the geocentric theory was supported by the Church.

Before the Scientific Revolution…

Ptolemy’s geocentric model of the solar system:

1. Earth2. Moon3. Mercury4. Venus5. Sun6. Mars7. Jupiter8. Saturn

Ptolemy(87-100 A.D.)

• Notice, the Earth is first, and not the sun, as it should be.

• In 1543 Copernicus published On the Revolutions of the Heavenly Spheres.

Nicolaus Copernicus

• Copernicus was a Polish astronomer who studied in Italy.

• In his book, Copernicus made two conclusions:

1. The universe is heliocentric, or sun-centered.

2. The Earth is merely one of several planets revolving around the sun.

Nicolaus Copernicus

Copernicus’ model of the solar system:

1. Sun2. Moon3. Mercury4. Venus5. Earth6. Mars7. Jupiter8. Saturn

• Notice, the sun is first, not the Earth, as Ptolemy believed.

Nicolaus Copernicus

• Copernicus came to these conclusions using mathematical formulas.

• The Copernican conception of the universe marked the start of modern science and astronomy.

The Copernican Heliocentric Model

Copernicus’s Scientific Theories:

• Considered the founder of modern science

• Believed that the earth was round and the earth revolved around the sun (contrary to popular belief)– The heliocentric theory was not new, but Copernicus established the

mathematical basis

• To avoid the risk of persecution, excommunication, or imprisonment because his were revolutionary and contrary to church beliefs, Copernicus worked in privacy for more than 30 years; just before his death, friends helped to published his work

• Copernicus’s theory was first taught in several universities in the 1500s and permeated the scientific world by 1600

• Most scholars rejected his theory because it went against Ptolemy, the Church, and because it called for the Earth to rotate on its axis.

• Many scientists of the time also felt that if Ptolemy’s reasoning about the planets was wrong, then the whole system of human knowledge could be wrong.

Reaction to Copernicus

Giordano Bruno: 1548 – 1600 AD• Italian monk• Believed Copernicus

was right and that the earth revolved around the sun

• Believed the earth was alive because it moves through space

• Believed the universe is huge and everything is made up of atoms

• He did not do original research; just used reason and speculation.

• Bruno wandered around Europe teaching and writing for a living.

• He returned to Italy and found trouble

Bruno vs the Inquisition

• Bruno had been offered a teaching job in Venice and thought his employer would protect him.

• Instead, Bruno was arrested by the Inquisition for not supporting the Geo-Centric Theory

• After seven years in prison, Bruno was tried as a heretic.

• He was burned at the stake for his scientific ideas.

• Then, in the late 1500s, the Danish astronomer Tycho Brahe provided evidence that supported Copernicus’ heliocentric theory. • Brahe set up an astronomical observatory.

Tycho Brahe

•Every night for years he carefully observed the sky, accumulating data about the movement of the stars and planets.

Tycho Brahe(1546-1601)

• Danish astronomer• Established an observatory

to study heavenly bodies• Accumulated a lot of data

on planetary movements• His tables of astronomical

observation was used by Kepler to prove Copernicus’s

helio-centric hypothesis

Brahe • Believed that the development of astronomy relied on

accurate observation

• Made lots of astronomical observation with the naked eye

• Built and calibrated numerous new instruments including:

• Created a domicile and observatory which he called Uraniborg

• After Brahe’s death, his assistant, the German astronomer and mathematician Johannes Kepler, used Brahe’s data and calculated the orbits of the planets revolving around the sun.

• Kepler’s calculations supported Copernicus’ heliocentric theory.

• His calculations also showed that the planets moved in oval shaped orbits, and not perfect circles, as Ptolemy and Copernicus believed.

Johannes Kepler

• Kepler’s finding helps explain the paths followed by man-made satellites today.

Johannes Kepler (1571-1630)

• Student of mathematics and astronomy• studied with Tycho Brahe• tested hypothesis after hypothesis until he

determined that planets move in ellipses• Three Laws of Planetary Motion

1 planets move in ellipses with sun as one focus2 velocity of a planet is not uniform3 equal area of the plane is covered in equal time

by the planets.

Johannes Kepler—(1571-1630)• Built on the detailed observations of Tycho Brahe.• Confirmed Copernicus’s heliocentric theory• Worked out the laws that governed planetary

motion.• Discovered that orbits were elliptical, not circular.• Killed off the Ptolemaic theory of crystalline spheres

and a perfect heaven.• Opens the door to the question of what the planets

and stars are made of and what governs their motion.

Johannes Kepler(1571-1630)

• Used Brahe’s work to successfully prove Copernicus’s helio-centric model mathematically

• However, he disproved Brahe’s claim that planets move in circular motion – found that they move in ellipses

• Discovered that the speed of planets increase as they near the sun and decrease as they go away from it

• Discovered three laws of planetary motion– the planets orbit the sun in elliptical orbits; the sun is at one focus of

the ellipse– An imaginary line drawn from the center of the sun to the center of a

planet will sweep out equal areas in equal intervals of time– The ratio of the squares of the periods of any two planets is equal to he

ratio of the cubes of their average distance from the sun • Worked in optics, discovered two new regular polyhedra,

created the first proof of logarithms, and created a way to find the volume of solids of revolution (which influenced calculus)– Proof of logs based off of the work of Napier and Euclid

Kepler Cont.:

• Very religious (protestant); believed in Intelligent Design, and that God made the Universe according to a mathematical plan –Math was considered a way to find truth, so Kepler

thought that this gave man a way to find and understand the truth of the Universe

• Worked as an aide to Tycho Brahe and continued Brahe’s work and used it in his own work

• Established the idea of observational error

Galileo Galilei• Galileo Galilei was an Italian astronomer who built upon the scientific foundations laid by Copernicus and Kepler.

• He also observed four moons rotating around Jupiter – exactly the way Copernicus said the Earth rotated around the sun.

• Galileo assembled the first telescope which allowed him to see mountains on the moon and fiery spots on the sun.

• Galileo also discovered that objects fall at the same speed regardless of weight.

Galileo Galilei• Galileo’s discoveries caused an uproar. Other scholars came against him because like Copernicus, Galileo was contradicting Ptolemy.

• The Church came against Galileo because it claimed that the Earth was fixed and unmoving.

• When threatened with death before the Inquisition in 1633, Galileo recanted his beliefs, even though he knew the Earth moved. • Galileo was put under house arrest, and was not allowed to publish his ideas.

The Scientific Method

• By the early 1600s, a new approach to science had emerged, known as the Scientific Method.

• Unlike earlier approaches, the scientific method did not rely on the classical thinkers or the Church, but depended upon a step-by-step process of observation and experimentation.

Scientific Method – painstaking method used to confirm findings and to prove or disprove a hypothesis.• Scientists observed nature, made

hypotheses, or educated guesses, and then tested these hypotheses through experiments.

1. State the problem2. Collect information3. Form a hypothesis4. Test the hypothesis5. Record & analyze data6. State a conclusion7. Repeat steps 1 – 6

The Scientific Method

• The scientific method set Europe on the road to rapid technological progress.

• Scientists soon discovered that the movements of bodies in nature closely followed what could be predicted by mathematics.

Newton • Sir Isaac Newton was an English scholar who built upon the work of Copernicus and Galileo.

The Scientific Method

• He used math to prove the existence of gravity - a force that kept planets in their orbits around the sun, and also caused objects to fall towards the earth.

• Newton was the most influential scientist of the Scientific Revolution.

• He invented calculus: a method of mathematical analysis.

• He discovered laws of light and color, and formulated the laws of motion:

• Newton published his scientific ideas in his book Mathematical Principles of Natural Philosophy.

The Scientific Method

Newton

1. A body at rest stays at rest2. Acceleration is caused by force3. For every action there is an

equal opposite reaction

According to a popular story, Newton saw an apple fall from a tree, and wondered if the force

that pulled the apple to the Earth also controlled the

movement of the planets. Newton argued that nature

followed laws.

The Scientific Method

Francis Bacon• Francis Bacon was an English philosopher who wrote Advancement of Learning.

The Scientific Method

• Bacon popularized the scientific method and used it with philosophy and knowledge.• Bacon argued that truth could not be known at the beginning of a question, but only at the end after a long process of investigation.

The Scientific Method

René Descartes• Descartes was a French scientist, mathematician, and philosopher. • Descartes emphasized human reasoning as the best road to understanding.

• Like Bacon, Descartes also believed that truth was only found after a long process of studying and investigation.

“I think, therefore I am”

Other Scientific Advances…

• In the 1600s Robert Boyle distinguished between individual elements and chemical compounds.

Chemistry

Robert Boyle

• Boyle also explained the effect of temperature and pressure on gases.

Robert Boyle’s first air pump

Medicine

Other Scientific Advances…

• In 1543 Andreas Vesalius published On the Structure of the Human Body.

Andreas Vesalius

• Vesalius’ book was the first accurate and detailed book on human anatomy.

Drawings done by Vesalius

William Harvey• An English scholar who described the circulation of blood for the first time.

Other Scientific Advances…

Medicine

•He showed how the heart served as a pump to force blood through veins and arteries.

• Venal valves had already been discovered, but here Harvey shows that venal blood flows only toward the heart. He ligatured an arm to make obvious the veins and their valves, then pressed blood away from the heart and showed that the vein would remain empty because it was blocked by the valve.

Other Scientific Advances…

Medicine

Ambroise Paré• French physician Ambroise Paré developed a new and more effective ointment for preventing infection.

• Paré also developed a technique for closing wounds with stitches.

Anton vonLeeuwenhoek

• A Dutch inventor who perfected the microscope and became the first human to see cells and microorganisms.

Other Scientific Advances…

Medicine