Movement of Pi Throughout History
By Alejandra Salinas

Four thousand years ago people discovered that the ratio of the circumference of a circle to its diameter was about 3.  People saw circles in nature and realized that this ratio was an important tool.  As mathematicians and scientists struggled to find a more accurate measurement of Pi, they found that Pi is an irrational number.  This means that it can't be accurately represented as a fraction and that it continues indefinitely after the decimal place. However, there are some fractions (such as 22/7) that are close enough to do most calculations.
Click Here to view the first 1000 digits of Pi.

Over a century after the discovery made in 1766 by  German mathematician and cartographer Lambert that Pi was irrational, another German mathematician named Lindeman calculated that Pi was also a transcendental number.  A transcendental number is one which cannot be the root of any algebraic equation with integer coefficients.  The base of the natural logarithm, known as e, is another number that has been proved irrational and transcendental.  Click Here to learn more about e.

It is interesting to note that both these discoveries were made in Germany.  Where have other discoveries about Pi been made?  The map below illustrates the progression of discoveries about Pi throughout time.  The findings about Pi began in Babylonia over 4,000 years ago and progress through a relatively small amount of countries.  Think about what these countries had in common in order to connect their interest in mathematics and the number Pi.   To further explore the mathematics that was occurring in these countries look at this MAP. 

MMapping the Advancement of Pi

On the above map, the darkest purple represents the region that has most recently made a discovery about Pi.  The regions get lighter in color as time passes after a discovery.

Value of Pi
Saudia Arabia/Iraq Babylonians ~2000 B.C. 3.125
Egypt Egyptians ~2000 B.C. 3.1605
China Chinese ~1200 B.C. 3
Israel/Egypt Found in Old Testament ~550 B.C. 3
Italy Archimedes ~300 B.C. 3.14163
Greece Ptolomy ~200 A.D. 3.14166...
China Chung Huing ~300 A.D. sqrt(10)=3.16...
China Wang Fau 263 A.D. 3.14
China Tsu Chung-Chi ~500 A.D. 3.1415926<Pi<3.1415929
India Aryabatta ~500 A.D. 3.1416
India Brahmagupta ~600 A.D. sqrt(10)=3.16...
Italy Fibonacci 1220 3.141818
Germany Ludolph van Ceulen 1596 Pi to 35 decimal places
England Machin 1706 100 decimal places
Germany Lambert 1766 Shows Pi is irrational
Germany Richter 1855 500 decimal places
Germany Lindeman 1882 Shows Pi is trascendental
England Ferguson 1947 808 decimal  places
USA Pegasus Computer 1957 7,840 decimal places
USA CDC 6600 1967 500,000 decimal places

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