Although there are measurement techniques that do appropriate pi, that’s done mostly because it’s interesting. Typically one calculate pi. The calculation cant ever be completed but the more you don’t the better your approximation. en.m.wikipedia.org/wiki/Leibniz_formula_for_π
That sort of stuff is done a lot. However, you don’t need all that many digits before adding more digits doesn’t meaningfully affect calculations. jpl.nasa.gov/…/how-many-decimals-of-pi-do-we-real…
owenfromcanada@lemmy.world 9 months ago
It’s been measured and approximated a lot of times.
To answer your question: it can be calculated/approximated mathematically, rather than by strictly measuring it.
Kaput@lemmy.world 9 months ago
That the problem I have about the situation. I’m thinking of a physical standard to calculated pi. Like the current kilogram sphere. Has anyone bothered to measure it’s radius and circumference with high precision tools. I’m not advocating to make pi legally 3.14. Just curious. If you do the calculation based on a micrometer vs millimeter tools you surely get a different result.
owenfromcanada@lemmy.world 9 months ago
The thing is, with a lot of constants like pi, any measurements are attempting to capture a “pure” infinitely-precise value. And doing calculations in a purely abstract context can get a lot closer to that mythical value than measuring with even our most precise tooling.
Think of it like this: we want to find the value of 1 + 1. So we create cubes that are 1 cm on each side, then we put two of them together and measure them. The measurement will not be exactly 2, it’ll have some error (maybe 1.999896cm, or 2.010102cm). But instead of using physical measures, we can create imaginary cubes that are exactly, perfectly 1cm and two together is exactly 2cm.
So we can do the same thing with special constants like pi, e, and lots of others, and we can get much greater accuracy than by measuring real-world objects.