**robertogreco : pi**
4

Pi Day is a lie: celebrate tau, the true circle constant instead - The Verge

march 2019 by robertogreco

[See also: https://www.youtube.com/watch?v=6acbBrLoi14 ]

"But Palais and Hartl’s arguments both boil down to some basic math. Step back in time to when you first learned geometry and recall the simple origins: no matter what circle you’re using, if you divide the circumference of the circle by the diameter, you’ll get the same answer: an endless number, starting with the digits 3.14159265... (aka pi).

And right there is the fundamental flaw. The thing is, we don’t actually use diameter to describe circles. We use the radius, or one-half the diameter. The circle equation uses the radius, the area of a circle uses the radius, and the fundamental definition of a circle — “the set of all points in a plane that are at a given distance from a given point, the center” — is based on the radius. Plugging that into our circle constant equation gives us a new circle constant equivalent to 2π, or 6.28318530717..., colloquially referred to with the Greek letter τ (tau). Switching to τ isn’t making some arbitrary change for the sake of it. It’s bringing one of the most important constants in math in line with how we actually do math."

math
mathematics
pi
2019
vihart
2018
tau
numbers
culture
"But Palais and Hartl’s arguments both boil down to some basic math. Step back in time to when you first learned geometry and recall the simple origins: no matter what circle you’re using, if you divide the circumference of the circle by the diameter, you’ll get the same answer: an endless number, starting with the digits 3.14159265... (aka pi).

And right there is the fundamental flaw. The thing is, we don’t actually use diameter to describe circles. We use the radius, or one-half the diameter. The circle equation uses the radius, the area of a circle uses the radius, and the fundamental definition of a circle — “the set of all points in a plane that are at a given distance from a given point, the center” — is based on the radius. Plugging that into our circle constant equation gives us a new circle constant equivalent to 2π, or 6.28318530717..., colloquially referred to with the Greek letter τ (tau). Switching to τ isn’t making some arbitrary change for the sake of it. It’s bringing one of the most important constants in math in line with how we actually do math."

march 2019 by robertogreco

Take It to the Limit - Opinionator Blog - NYTimes.com

april 2010 by robertogreco

"What’s so charming about this calculation is the way infinity comes to the rescue. At every finite stage, the scalloped shape looks weird and unpromising. But when you take it to the limit — when you finally “get to the wall” — it becomes simple and beautiful, and everything becomes clear. That’s how calculus works at its best."

math
infinity
archimedes
pi
circles
circumference
area
calculus
mathematics
via:migurski
proof
visualization
geometry
limits
education
history
april 2010 by robertogreco

Cadaeic Cadenza is a 3834-word story by Mike Keith where... (kottke.org)

september 2007 by robertogreco

"Cadaeic Cadenza is a 3834-word story by Mike Keith where each word in sequence has the same number of letters as the corresponding digit in pi."

math
literature
stories
writing
pi
september 2007 by robertogreco

Copy this bookmark: