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History of Mathematics

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Sumerian/Babylonian Mathematics

  • Sumer is a region in Mesopotamia (modern day Iraq)
  • the birthplace of writing, the wheel, agriculture, the arch, the plow, irrigation and many other innovations
  • Developed the earliest known writing system (cuneiform), so we have lots of knowledge of their math

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Sumerian/Babylonian Mathematics

  • Math developed for the Sumerians as a response to bureaucratic needs: measurements of plots of land, taxation, large numbers to chart the night sky and develop a lunar calendar
  • Around 6000-3000 BC they moved from using symbols of items (wheat, jars, etc) to symbols to represent numbers of items.

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Sumerian/Babylonian Mathematics

  • From around 3000-2000 BC they moved from symbols to representing numbers in the cuneiform text
  • Base 60 number system (any idea why??)
  • Where do we use a base 60 number system still today?

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Sumerian/Babylonian Mathematics

Can you see how their number system works?

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Sumerian/Babylonian Mathematics

What about numbers greater than 59??

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Sumerian/Babylonian Mathematics

Which number is shown?

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Sumerian/Babylonian Mathematics

Some more mathematics:

  • New how to square numbers (useful for plots of land)
  • Areas of rectangles, triangles
  • Volumes of bricks and cylinders
  • First solutions of quadratic equations
  • Right triangle secret??

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Egyptian Mathematics

  • Early Egyptian settled on the Nile as early as 6000BC
  • Needed to measure land and develop a lunar calendar for agricultural reasons
  • Used measurements based on body parts
  • Developed a decimal number system (notice still no place value so bigger numbers are hard to write)

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Egyptian Mathematics

The Rhind Papyrus, dating from around 1650 BCE, is a kind of instruction manual in arithmetic and geometry, and it gives us explicit demonstrations of how multiplication and division was carried out at that time. It also contains evidence of other mathematical knowledge, including unit fractions, composite and prime numbers, arithmetic, geometric and harmonic means, and how to solve first order linear equations as well as arithmetic and geometric series.

The Berlin Papyrus, which dates from around 1300 BCE, shows that ancient Egyptians could solve second-order algebraic (quadratic) equations.

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Egyptian Mathematics

Egyptian fractions

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Egyptian Mathematics

Area of a Circle

The Egyptian approximated the area of a circle using shapes they knew. They were even able to approximate pi to within 1% accuracy!

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Egyptian Mathematics

The Pyramids required some math to build as well

  • Golden ratio
  • Volume
  • Even new pythagorean theorem (before Pythagoras)

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Greek Mathematics

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Greek Mathematics

  • As the Greek empire spread, they adopted some of the mathematical ideas found in Sumeria and Egypt. They soon started to make contributions of their own

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Greek Mathematics

  • Had their own number system (similar to Egyptian, Sumerian, and Roman Numerals)
  • Most math based on geometry
  • Loved solving problems

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Greek Mathematics

The Paradox of Achilles and the Tortoise

A theoretical race between Achilles and a tortoise. Achilles gives the much slower tortoise a head start, but by the time Achilles reaches the tortoise's starting point, the tortoise has already moved ahead. By the time Achilles reaches that point, the tortoise has moved on again, etc, etc, so that in principle the swift Achilles can never catch up with the slow tortoise.

** eventually disproved.

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Pythagoras

-often called the first mathematician

-established a school in Italy around 530BC. Mostly based on math but also mystical.

-Left no mathematical writings, his thoughts have come to us through the writings of his scholars, so we don’t actually know if his theorems were solved by him or his followers.

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Pythagoras

  • School divided into mathematikoi (learners) who extended and developed Pythagoras’ ideas and akousmatikoi (listeners) who focused more on religious aspects.
  • There was always a certain amount of friction between the two groups and eventually the sect became caught up in some fierce local fighting and ultimately dispersed. Resentment built up against the secrecy and exclusiveness of the Pythagoreans and, in 460 BCE, all their meeting places were burned and destroyed, with at least 50 members killed in Croton alone.

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Pythagoras

“All is Number”

  • Pythagoreans practiced a sort of number worship
  • Ex) 2=opinion 3=harmony etc
  • 10 was the holiest of all numbers

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Pythagoras

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Pythagoras

Pythagoras is also credited with the discovery that the intervals between harmonious musical notes always have whole number ratios. For instance, playing half a length of a guitar string gives the same note as the open string, but an octave higher; a third of a length gives a different but harmonious note; etc. Non-whole number ratios, on the other hand, tend to give dissonant sounds

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Plato

  • Often thought of as a philosopher but was also a mathematician
  • Started his own academy in Athens in 387 BC
  • Inspired Greek philosophers to study math as well
  • Sign above the academy read “Let No One Ignorant of Geometry Enter Here”
  • He demanded of his students accurate definitions, clearly stated assumptions, and logical deductive proof, and he insisted that geometric proofs be demonstrated with no aids other than a straight edge and a compass.

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Plato

Plato the mathematician is perhaps best known for his identification of 5 regular symmetrical 3-dimensional shapes, which he maintained were the basis for the whole universe, and which have become known as the Platonic Solids: the tetrahedron (constructed of 4 regular triangles, and which for Plato represented fire), the octahedron (composed of 8 triangles, representing air), the icosahedron (composed of 20 triangles, and representing water), the cube (composed of 6 squares, and representing earth), and the dodecahedron (made up of 12 pentagons, which Plato obscurely described as “the god used for arranging the constellations on the whole heaven”).

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Hellenistic Mathematics

  • From Alexander the Great’s death to the emergence of the Roman Empire. (323 BC -31 BC)
  • Alexandria in Egypt became a great centre of learning.
  • Many great minds studied at the library in Alexandria

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Euclid

  • Lived around 300 BC
  • Almost nothing is known of his life and no portraits have survived
  • He probably studied for a time at Plato’s academy
  • Often called ‘the father of geometry’
  • Wrote the greatest math textbook of all time “Elements”. A compilation of all know mathematics at the time.
  • contains 465 theorems and proofs, described in a clear, logical and elegant style, and using only a compass and a straight edge.

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Euclid

Euclid set the model for mathematical arguments. From initial assumptions to logical deductions. He called these axioms (all math) and postulates (geometry). These were unproven truths which he used to prove other theorems.

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Euclid

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Euclid

Among many other mathematical gems, the thirteen volumes of the “Elements” contain formulas for calculating the:

-volumes of solids such as cones, pyramids and cylinders;

-proofs about geometric series, perfect numbers and primes;

-algorithms for finding the greatest common divisor and least common multiple of two numbers;

-a proof and generalization of Pythagoras’ Theorem, and proof that there are an infinite number of Pythagorean Triples;

-and a final definitive proof that there can be only five possible regular Platonic Solids.

-Proof there are an infinite number of prime numbers

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Euclid

Fundamental Theorem of Arithmetic: Any integer greater than 1 is either prime or can be represented by a unique representation of prime numbers.

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Euclid

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Archimedes

  • 287 - 212 BC
  • Lived in Syracuse, Sicily
  • Engineer, inventor, astronomer, mathematician
  • Archimedes Palimpsest was found in 1906 and gave greater insight in his mathematical works

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Archimedes

Military Inventions helped Syracuse hold off a Roman siege for 3 years

Archimedes Claw

Archimedes Death Ray

catapult

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Archimedes

Other Inventions:

An Archimedes' screw, also known by the name the Archimedean screw or screw pump, is a machine used for transferring water from a low-lying body of water into irrigation ditches. Water is pumped by turning a screw-shaped surface inside a pipe.

“Give me a place to stand on and I will move the Earth”

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Archimedes

Mathematics

  • Estimated a value for pi using constructing polygons inside and outside of the circle. (method of exhaustion) His estimate was between 317 (approximately 3.1429) and 31071 (approximately 3.1408),
  • Showed that the volume and surface area of a sphere are ⅔ that of a cylinder with the same diameter
  • He even calculated the number of grains of sand required to fill the universe, using a system of counting based on the myriad (10,000) and myriad of myriads (100 million). His estimate was 8 vigintillion, or 8 x 1063.

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Archimedes

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Archimedes

Death

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Roman Mathematics

  • Roman empire (27 BC-395 AD)
  • Most mathematics ground to a halt
  • Roman Numerals were the dominant number system in Europe for over a millennium
  • We still use them today!
  • No 0, and hard to do arithmetic with (calculations were often done on an abacus instead)

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Hypatia

  • 355 -415 AD
  • Lived in Alexandria
  • Mathematician, astronomer, philosopher
  • Often called the first female mathematician
  • Father Theon was also a Mathematician

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Hypatia

  • In difficult times, her and her father tried to preserve Greek and Mathematical texts in the library at Alexandria
  • Credited with commentaries in two great mathematical texts Apollonius of Perga’s “Conics” and Diophantus of Alexandria’s “Arithmetic”

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Hypatia

  • Followed and taught the ideas of “Plato” which were seen as pagan
  • Conflict between Jews,Christians, and Pagans in Alexandria (much of the library’s contents were destroyed in conflicts)
  • Hypatia’s views conflicted with the main Christian views in the city. The Archbishop Cyril ordered her killed. The mob proceeded to drag her through the streets as they tortured her. The monks burned Hypatia and scraped her skin off with oyster shells. They then took her to a church where they stripped her naked, beat her with tiles, and tore her limbs from her body.

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Chinese Mathematics

  • As the Greek mathematical developments began to falter, burgeoning trade in China was brining it’s mathematics to new heights.
  • By the 13th Century there were over 30 prestigious math schools across China
  • Used small bamboo rods to represent numbers.
  • The first decimal place value system!
  • Notice, still no 0

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Chinese Mathematics

Magic Squares

Lo Shu Square- each row and column adds to 15 dates to 650 BC

Eventually came up with even bigger magic squares

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Chinese Mathematics

  • Main thrust of math was developed in a need for competent administrators who could handle problems in trade, tax, engineering, and wages.
  • A textbook called “Jiuzhang Suanshu” or “Nine Chapters on the Mathematical Art” (written over a period of time from about 200 BCE onwards, probably by a variety of authors)

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Chinese Mathematics

Liu Hui

  • Around 263 AD
  • One of first mathematicians to leave roots unevaluated, leaving more exact answers
  • Calculated the value of pi to 5 decimal places using a 192 sided polygon
  • Developed early forms of calculus

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Indian Mathematics

  • Developed some very advanced mathematical discoveries (independent of Chinese and Babylonian cultures) as early as between 1000BC &700BCE

ex)

  • Could evaluate powers of 10 from 100 to 1 trillion
  • Evidence they could enumerate a number equivalent to(10421)
  • Basic operations, squares, cubes, and roots
  • Simplified statement of Pythagorean theorem for sides of rectangles
  • Estimated square root of 2 up to 5 decimal places
  • Solve linear and quadratic equations

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Indian Mathematics

Used a place value system (like Chinese and us today) as early as 3rd century BC

Beginnings of 9 numerals we use today

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Indian Mathematics

The Indians were also responsible for another hugely important development in mathematics. The earliest recorded usage of a circle character for the number zero is usually attributed to a 9th Century engraving in a temple in Gwalior in central India.

The use of a number 0 in calculations would revolutionize mathematics!

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Indian Mathematics

Golden age of Indian Mathematics (5th to 12th centuries)

-many discoveries predated Western discoveries by several centuries (plagiarism by Western mathematicians?)

-made advances in trigonometry. Used to calculate distances between sun, moon and Earth

-Bhaskara II credited with explaining the previously misunderstood concept of dividing by 0

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Brahmagupta

-7th century Indian Mathematician and Astronomer

-from the state of Rajasthan of northwest India

-Most of his works are composed in elliptic verse, a common practice in Indian mathematics at the time, and consequently have something of a poetic ring to them.

-the first to use zeros and negatives in computations. First to use the rule that two negatives multiplied together make a positive (although no proof given)

-his works brought to the newfound centre of learning in Baghdad and helped lead the expansion of Muslim mathematics

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Islamic Mathematics

-The Islamic Empire established across Persia, the Middle East, Central Asia, North Africa, Iberia and parts of India from the 8th Century onwards

-made significant contributions towards mathematics.

-They were able to draw on and fuse together the mathematical developments of both Greece and India.

-House of Wisdom set up in Baghdad in 1810

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Islamic Mathematics

Mastered the art of symmetry in the form of art to decorate their buildings

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Muhammad Al-Khwarizmi

-one of the directors of the House of Wisdom in the early 9th century

-oversaw translation of Greek and Indian works into Arabic

-The word “algorithm” is derived from the Latinization of his name, and the word "algebra" is derived from the Latinization of "al-jabr", part of the title of his most famous book, in which he introduced the fundamental algebraic methods and techniques for solving equations.

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Muhammad Al-Khwarizmi

-strongly advocated for the Hindu number system (1-9 and 0) and the Hindu-Arabic number system was soon adopted by the entire Islamic world and later on the European world (through Fibonacci)

-published in about 830 called “Al-Kitab al-mukhtasar fi hisab al-jabr wa'l-muqabala” (“The Compendious Book on Calculation by Completion and Balancing”. Al-Khwarizmi wanted to go from the specific problems considered by the Indians and Chinese to a more general way of analyzing problems, and in doing so he created an abstract mathematical language which is used across the world today. (not same notation we used today but with words and pictures)

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Medieval European Mathematics

-5th to 15th Centuries

-While Chinese, Indian, and Islamic mathematics flourished, Europe was stuck in the dark ages where science, math, and almost all intellectual endeavors stopped

-all trade done using clumsy Roman Numeral system and using an abacus based on Roman and Greek models

-things starting to look up:

-12th Century beginning to trade with East

-15th Century printing press invented (some math texts translated)

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Fibonacci

-The 13th Century Italian Leonardo of Pisa, better known by his nickname Fibonacci

-son of a customs official, travelled around North Africa with his father where he learned Islamic Mathematics

-started to share this knowledge upon his return to Europe, setting in motion a rejuvenation of European Mathematics

-In 1202, he wrote a hugely influential book called “Liber Abaci” ("Book of Calculation"), in which he promoted the use of the Hindu-Arabic numeral system, describing its many benefits for merchants and mathematicians alike over the clumsy system of Roman numerals then in use in Europe.

-First to use horizontal bar to separate numerator and denominator

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Fibonacci

1,1,2,3,5,8,13

-discovered this sequence while researching a hypothetical problem for his book.

-evidence it was known in India already

-as time went on other people began to discover even more real life examples of this sequence

-Sequence named after him in 1877

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Fibonacci

in the 1750’s Robert Simson discovered the Golden ratio from this sequence

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16th Century Mathematics

  • The Renaissance began in Italy in the 14th Century and saw a resurgence of culture, intelligence, and art. This gradually spread across Europe over the next 2 centuries.
  • Math and art were very much interconnected at this time
  • ex ) Melencolia 1

Albrecht Durer

Supermagic square

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16th Century Mathematics

-Common math symbols begin to appear and spread

-Friar Luca Paciola

-book of puzzles

-symbols for + and - first seen in a printed book

-exploring the golden ratio: “a message from God and a source of secret

knowledge about the inner beauty of things.”

-Simon Steven

-first to use decimal arithmetic

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Niccolo Tartaglia

-first translation of Euclid’s ‘Elements’ in a modern European language

-investigation of cannonball paths

-revealed formula for solving all cubic equations at a math competition

-first understanding of square roots of negatives (imaginary numbers)

-Gerolamo Cardano published his solution to solving quartics without his knowledge

-Ferrari (protege of Cardano) challenged Tartaglia to public debate. Tartaglia didn’t show up.

-Tartaglia died penniless and unknown

-Ferrari got a prestigious teaching post and became rich

-Cardano wrote first book on probability...short on money whole life due to gambling problems

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17th Century Mathematics

-At end of Renaissance there was an explosion of Math and Science. Often called the ‘Age of Reason’

-Scientists like Galileo Galilei, Tycho Brahe and Johannes Kepler were making equally revolutionary discoveries in the exploration of the Solar system (Copernicus had just shown that the Sun was the centre of the Solar System)

-Math was needed to help Scientists

-Invention of logarithm by John Napier helped make difficult calculations easy for Scientists as they dealt with large numbers

The logarithm of a number is the exponent when that number is expressed as a power of 10 (or any other base). It is effectively the inverse of exponentiation.

Ex) Log10 100 = 2 since 102=100

Rules for adding and subtracting logarithms make it easier to calculate with larger numbers

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Rene Descartes

-”Father of Modern Philosophy”, but also a key figure in the Scientific Revolution and considered the first of the modern school of mathematics.

-mercenary soldier for Catholic and Protestant armies

-eventually concluded real path was true wisdom and science

-believed key to ambiguities of philosophy was to build it on indisputable facts of math

-moved from Catholic France to more liberal Netherlands to explore ideas

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Rene Descartes

In 1637, he published his ground-breaking philosophical and mathematical treatise "Discours de la méthode" (the “Discourse on Method”), and one of its appendices in particular, "La Géométrie", is now considered a landmark in the history of mathematics

-introduced standards for algebraic notation (using a,b,c for known quantities and x,y,z for unknown quantities)

-proposed that each point in two dimensions can be described by a horizontal and vertical location (Cartesian Plane and Cartesian/Analytic Geometry)

-soon became easier to plot equations and see their shapes. Now had a link between geometry and algebra

-popularized the use of a superscript for exponents

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Pierre de Fermat

-lawyer and small town “amateur” mathematician, effectively developed modern number theory from 1601-1655

-mathematical work mainly included in letters to friends, limited proofs of theorems.

-Fermat’s Little Theorem is often used in the testing of large prime numbers, and is the basis of the codes which protect our credit cards in Internet transactions today.

-Fermat's pièce de résistance, though, was his famous Last Theorem, a conjecture left unproven at his death, and which puzzled mathematicians for over 350 years

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Blaise Pascal

-1623-1662

-Child prodigy (wrote a treatise called Pascal’s Theorem when he was 16 and built a machine to help add and subtract numbers)

-Scientist, philosopher, and mathematician (international unit for pressure measurement named after him)

-In philosophy, Pascal had a pragmatic approach to believing in God on the grounds that is it is a better “bet” than not to.

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Blaise Pascal

-many different patterns in Pascal’s Triangle

-used Pascal's triangle to help solve probability problems (subject of mathematical theory of probability was born)

-Pascal, along with Fermat, brought previous probability knowledge together to solve unsolved problems

Problem of Points:

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Blaise Pascal

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Sir Isaac Newton

1643-1727

Physicist, mathematician, astronomer, natural philosopher, alchemist and theologian, Newton is considered by many to be one of the most influential men in human history.

His 1687 publication, the "Philosophiae Naturalis Principia Mathematica" (usually called simply the "Principia"), is considered to be among the most influential books in the history of science

Over two miraculous years, during the time of the Great Plague of 1665-6, the young Newton developed a new theory of light, discovered and quantified gravitation, and pioneered a revolutionary new approach to mathematics: infinitesimal calculus

Unlike the static geometry of the Greeks, calculus allowed mathematicians and engineers to make sense of the motion and dynamic change in the changing world around us, such as the orbits of planets, the motion of fluids

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Sir Isaac Newton

Derivatives (fluxion)

Integral (fluents)

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Sir Isaac Newton

-chose not to publish his findings on calculus for fear of being ridiculed for unconventional ideas (finally published later on in 1693)

-Leibniz published his own version of the theory first

-credit for discovery to Newton and for first publication to Leibniz.

-wrote a number of books on a literal interpretation of the Bible

-first scientist ever knighted

-mercury poisoning from experiments led to eccentricity and death

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Gottfried Wilhelm Leibniz

1646-1716

-philosopher, logician, mathematician, politician

-developed early ideas of Calculus (along with Newton) although we still use his notation in Calculus today

-arranged linear equations in a matrix in order to solve them

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Gottfried Wilhelm Leibniz

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Gottfried Wilhelm Leibniz

Developed binary number system in order to convert verbal logic statements into mathematical ones (True and False, 1 and 0)

Binary is the basis of our computer systems today!

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18 Century Mathematics

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Bernoulli Brothers

-prosperous family of traders and thinkers from Basel Switzerland

-Jacob and Johan resisted their fathers wishes to go into the family spice trade or enter medicine to instead focus on mathematics

-Had a very competitive rivalry (Johann jealous of Jacob’s position as a professor at Basel University)

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Bernoulli Brothers

-among the first to not only study calculus, but apply it to problems. Helped make calculus a cornerstone of math today.

Also discovered an approximate value for e. While exploring the compound interest on loans.

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Leonhard Euler

-1707-1783

-student of Bernoulli Brothers

-did most work in Russia and Germany (due to dominance of Bernoulli family in Switzerland)

-his collected works comprises over 900 books across all topics in math(in 1775 comprised one mathematical paper every week!)

-had a photographic memory

-considered one of the greatest mathematicians of all time

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Leonhard Euler

-helped standardized common math notation. Which made it easier for collaboration on problems

-The most remarkable equation in math. Euler’s Identity (combines arithmetic, calculus, trigonometry, and complex numbers)

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Leonhard Euler

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19th Century Math

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Galois

-French mathematician

-lacklustre performance in school (twice failed entrance exams to the University)

-studied works of other mathematicians in his spare time

-hot-head and radical republican (twice arrested for political acts)

-died in a duel at age 20 (spent the night before outlining math ideas to a friend)

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Galois

-proved there was no general formula for solving a degree 5 (quintic) equation

-Galois’ breakthrough in turn led to definitive proofs (or rather disproofs) later in the century of the so-called “Three Classical Problems” problems which had been first formulated by Plato and others back in ancient Greece: the doubling of the cube and the trisection of an angle (both were proved impossible in 1837), and the squaring of the circle (also proved impossible, in 1882).

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Gauss

-Carl Friedrich Gauss

- “Prince of Mathematics”

-child prodigy, made his first groundbreaking mathematical discovery while still a teenager

-At the age of 3 he found an error on his Father’s payroll calculations and he was looking after his Father’s accounts by age 5.

-At the age of 7 he amazed his teachers by summing the numbers 1 to 100 almost instantly.

How did he do it!? 1+2+3+.....+98+99+100=????

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Gauss

-First to see a pattern in the occurrence of prime numbers

-Most contributions were in the area of number theory

-popularized practice and standard notation for complex numbers

-proved the fundamental theorem of algebra

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Riemann

-Bernhard Riemann

-another child prodigy

-extremely shy and timid

-devoutly religious, tried to mathematically prove the correctness of the Book of Genesis

-studied under Gauss

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Riemann

-developed a non-Euclidean geometry called elliptic geometry

-vision of mathematics that was in more than just 2D and 3D space into multi-dimensions

-this later enabled the development of general relativity by Einsten

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George Boole

George Boole (1815-1865) British Mathematician

First to see logic as a mathematical discipline

Boolean logic-form of algebra in which all values can reduced to be true or false

Helped establish modern symbolic logic and whose algebra of logic, now called Boolean algebra, is basic to the design of digital computer circuits.

Ideas largely ignored until almost 70 years later that electromechanical relay circuits could be used to solve Boolean algebra problems. The use of electrical switches to process logic is the basic concept that underlies all modern electronic digital computer

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George Boole

True AND False

True AND True

True OR False

False OR False

NOT True

1+3 =5 OR 2+6=8

NOT (2+5=7 AND 3+6=9)

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20th Century Mathematics

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Hardy and Ramanujan

-Hardy was a British Mathematician, who is credited with reforming British mathematics

-child prodigy, used to amuse himself at Church factorizing hymn numbers

-Ramanujan was an Indian, self taught, mathematician, wrote to University of Cambridge, claiming some of his exploits...Hardy was the only one to recognize genius and brought him to the University

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Hardy and Ramanujan

-Ramanujan conjectured or proved over 3,000 theorems, identities and equations, including properties of highly composite numbers, the partition function and its asymptotics and mock theta functions

-He also carried out major investigations in the areas of gamma functions, modular forms, divergent series, hypergeometric series and prime number theory.

-Among his other achievements, Ramanujan identified several efficient and rapidly converging infinite series for the calculation of the value of π, some of which could compute 8 additional decimal places of π with each term in the series. These series (and variations on them) have become the basis for the fastest algorithms used by modern computers to compute π to ever increasing levels of accuracy (currently to about 5 trillion decimal places).

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Alan Turing

-most famously known for his work on breaking the enigma code at Bletchley Park in WW2 (Imitation Game movie about him)

-developed the Turing Machine and Turing Test before computers were invented

-worked on some of the earliest computers

-arrested in 1952 and charged with homosexuality, committed suicide in 1954

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Alan Turing