STEM Lores

The stories behind the videos

The written story behind every Math Lore, Physics Lore and Chemistry Lore video: the people, the dates, the ideas.

Physics Lore · 2 min readWhy Feynman Told Physicists to Hang 137 on the WallIn 1985 Richard Feynman picked out one number for physicists to worry about. More than forty years on, it is measured to twelve digits and still unexplained.Physics Lore · 6 min readWhy Does 137 Haunt Physics? The Strange Story of the Fine-Structure ConstantA pure number with no units sets how strongly light grips matter. We have measured it to twelve digits, and nobody can say why it is 1/137.Math Lore · 3 min readThe Mutilated Chessboard Problem: Why 31 Dominoes Can't Cover 62 SquaresThe area matches exactly. The colors do not. A puzzle from a 1946 logic textbook shows how the right way of looking beats any amount of trial and error.Math Lore · 6 min readWhy Is e = 2.718…? How Compound Interest Found the Number of GrowthNobody chose the number 2.718281828…; let growth feed on itself and it answers, in banks, in atoms, in luck and in a circle.Math Lore · 3 min readHow Many Ways Can 4 Letters All Go in the Wrong Envelopes? The Story of DerangementsMost people guess the chance is below one third. Count the shuffles and every letter goes wrong more often than that, with e hiding in the answer.Math Lore · 3 min readCompound Interest and the Number e: Why Your Balance Stops Near 2.718Split one year's interest into ever smaller payments and the money does not explode. It creeps up toward a single number, and Jacob Bernoulli found it first.Math Lore · 6 min readWhat Is Pi, Really? Why π Is the Unit of Turning, Not Just 3.14Circumference over diameter is where π starts, not what it is. Follow it from Archimedes' polygons to half a turn, and to a sphere where the ratio fails.Math Lore · 3 min readWhy the Square Root of 2 Broke the Pythagoreans: The Diagonal That Ended a ReligionA square with sides of 1 has a diagonal that no ratio of whole numbers can measure. That fact cut straight through a brotherhood that believed all is number.Math Lore · 3 min readWhy Doubling Beats Everything: Exponential Growth, Folded Paper and a ChessboardA sheet one tenth of a millimeter thick, doubled 42 times, ends up farther away than the Moon. Here is why doubling leaves steady adding behind.Math Lore · 7 min readWhy Is the Square Root of 2 Irrational? The Number That Broke MathematicsA square's diagonal cannot be measured by any fraction. Here is the short proof, the legend it grew, and the question it left open until 1872.