Summary of The Discovery That Transformed Pi
00:00:00This video explores the history of calculating Pi and how Isaac Newton revolutionized the process. Initially, a basic method involved inscribing shapes like hexagons and squares within a circle to approximate Pi between 3 and 4. Archimedes later refined this by using regular 12-sided shapes to narrow down Pi's value further. This intricate process involved calculating perimeters and extracting square roots to arrive at a more accurate range for Pi, eventually reaching between 3.1408 and 3.1429 with a 96-sided shape.
00:03:11For over 2000 years, mathematicians worked on calculating Pi to higher precision, with each mathematician contributing to the bounds. In the late 16th and early 17th centuries, Francois Viete and Ludolph van Ceulen calculated Pi with increasing accuracy by bisecting polygons with numerous sides. However, in 1666, Sir Isaac Newton introduced a faster method using Pascal's triangle to calculate coefficients for expressions like one plus X raised to various powers, revolutionizing the computation of Pi. Pascal's triangle is a mathematical tool that helps determine these coefficients quickly by adding the two neighboring numbers in each row. Newton's method eliminated the need for tedious arithmetic calculations, making the computation of Pi more efficient.
00:06:24The speaker discusses the fascination of seeing various ancient civilizations independently discover Pascal's triangle and how mathematics transcends cultures and time. They explain the binomial theorem and how Newton extended it by applying it to negative exponents, resulting in an infinite series with alternating coefficients. This transformation from a finite to an infinite series was a groundbreaking discovery that changed the way the binomial theorem was understood.
00:09:10The formula for the coefficient in Newton's infinite series involves multiplying consecutive numbers up to a certain point based on the value of N. When N is a positive integer, the coefficients beyond N become zero, resulting in a finite sum within a triangle pattern. However, for non-positive integer values of N, the series extends infinitely beyond the triangle. Newton believed in the validity of applying the binomial theorem to negative values of N, leading to a new understanding of Pascal's triangle with additional rows containing alternating positive and negative numbers summing to zero. This pattern resembles the original triangle but rotated. Newton further explored fractional exponents in the series, such as √(1 + X), which yielded an infinite series similar to the integer expansions. This revelation suggests a broadening of Pascal's triangle to incorporate fractional values between the existing rows.
00:12:03Between zero and one, there is a continuum of numbers representing fractions like a half or a quarter on their own plane. These fractions can be manipulated using series expansions, such as finding square roots efficiently. Newton used N equals a half to explore equations for a unit circle, leading to a way to represent a circle as an infinite series of irrational numbers multiplied by X raised to various powers. By integrating under the curve as X goes from zero to one, Newton calculated Pi by finding the area of a quarter circle and then using a series expansion to further refine the value of Pi with increasing precision.
00:14:36A bad math paper lacks new ideas and simply reiterates known concepts. Newton introduces a groundbreaking new idea of integrating only from zero to a half instead of zero to one, improving calculation efficiency. By reducing the integration range, Newton achieves accurate results with fewer computations, revolutionizing the approach to finding Pi. This story highlights the importance of challenging traditional methods and exploring new possibilities in mathematics to enhance understanding and efficiency.
00:17:26Brilliant is a website offering interactive courses and quizzes on topics like calculus, neural networks, programming, and Python. They emphasize problem solving and scaffolding to build understanding and confidence. The narrator, with a PhD in science education, believes that active engagement is the best way to learn. Brilliant is offering 20% off an annual subscription to the first 314 or 100 people to sign up via the link brilliant.org/.veritasium.