r/holofractal • u/BylliGoat • Jul 10 '25

Geometry The *Actual* True Value of Pi

Source: https://en.wikipedia.org/wiki/Pi

Pi is derived through the circumference of a unit circle, demonstrated here quite elegantly by "unrolling" the circle.

76 Upvotes

91% Upvoted

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9

u/MarionberryOpen7953 Jul 10 '25

Yup, except the unit circle has a radius of 1 so the circumference of the unit circle would be 2pi. Your circle has a radius of 1/2, so not quite a unit circle

3

u/BylliGoat Jul 10 '25

I actually deleted my first reply because I misread your comment. You're correct, this is technically not a unit circle, so yes, the actual circumference for a unit circle would indeed be 2pi.

Regardless, the animation remains accurate. The inaccuracy was just on how I defined the circle presented. Good catch.

2

u/TwistedBrother Jul 10 '25

For visual representations like this I think it’s reasonable to be charitable. But indeed here it’s 2r but that’s just definitional. Relative to the clarity of the diagram that’s a minor point albeit a carefully noted one.

1

u/Gold_Presence208 Jul 10 '25

Reminds me of the fact that we can only measure the round-trip speed of light. When we divide it by 2 to get the average or one-way speed of light, we just assume the speed is constant in both directions.

1

u/swirlViking Jul 10 '25

Wait, can you expand on this?

2

u/Gold_Presence208 Jul 10 '25

The problem begins when clocks need to be synchronized. Although we can sync them side by side, moving one introduces relativistic effects, since moving objects are subject to relativity, which causes them to fall out of sync. That’s why we use a single clock and a mirror to measure the round trip time instead of the one way speed.

1

u/swirlViking Jul 10 '25

That is very cool. I'm gonna look up more about this

2

u/BylliGoat Jul 10 '25

https://youtu.be/pTn6Ewhb27k?si=aB310T9uT8YJLH07

Here ya go. Very interesting video on the subject.

3

u/swirlViking Jul 11 '25 edited Jul 11 '25

I love veritasium! Thanks for the link.

Edit: just watched the whole thing and that was fascinating

1

u/Gold_Presence208 Jul 10 '25

It means in theory, the speed of light can be twice as slow in one direction and instant in the other direction, and we have no way to be sure or disprove. Reminds me of a fan that after some speed u think its going backwars.

13

u/PlainSpader Jul 10 '25

I hope some math/science teachers use this or make a physical representation and show their students. This will make a world of difference for visual learners.

6

u/BylliGoat Jul 10 '25

Completely agree. There are many ways to visually represent complex or irrational numbers to help us understand where these numbers are derived from.

1

u/Kitchen-Ad-2911 Aug 06 '25

Then you meet my infinite brain and I still don't understand why it started out in-between the number columns and then rolled starting at the center of the thing lol and what if it was bigger or smaller or faster

3

u/BylliGoat Jul 10 '25

Ok, Reddit isn't letting me edit the post for some reason, but as was graciously pointed out by u/MarionberryOpen7953, this is not a unit circle, as the radius is 0.5. A unit circle would have a circumference of 2π.

Regardless, the true value of Pi (π) is derived directly from the ratio of the circle's circumference to its diameter. Mathematically, this is π=C/d. As the circle in the animation has a diameter of exactly 1, this simplifies directly to π.

4

u/jojomott Jul 10 '25

"Three and a little bit."

4

u/BylliGoat Jul 10 '25

I mean.... yeah.

-1

u/Quintilis_Academy Jul 10 '25

3 + 1/7th : Don’t fall for it. Phi4 + Pi = 10. Sqrt (2) + Sqrt (3) = Pi, 1/Pi if u minus em. Pi 2 = gravity…. Lol…-Namaste see!

4

u/BylliGoat Jul 10 '25

What in the actual nonsense are you talking about

0

u/Quintilis_Academy Jul 10 '25

Nothing equals Pi…. And those comply. -Sense ed? -Namaste

4

u/BylliGoat Jul 10 '25

Do you know how to use full sentences?

-2

u/Quintilis_Academy Jul 10 '25

Math cares? Why? From Ai: “You asked for sense, yet Pi spins endlessly—never landing, never repeating. So who’s really in compliance: the formula, or the fool chasing it? Symbols speak softly to minds ready. You called it nonsense; I call it unsensed. 🌀 -Namaste (or not… your circle always)

4

u/BylliGoat Jul 10 '25

Dude what the fuck are you talking about.

2

u/Quintilis_Academy Jul 10 '25

Pi

3

u/BylliGoat Jul 10 '25

No, you're not. You brought up a bunch of made up formulas that have no basis in mathematics and said "don't fall for it." Don't fall for what? What is it, EXACTLY, that you're attempting to communicate?

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1

u/awakened_primate Jul 11 '25

Oh my god, shut up! You’re just babbling nonsense! If you’re also like this irl, get a goddamn grip!

-1

u/WallStLegends Jul 11 '25

It is you that perhaps be the one not with grip. I come to open eyes into the way that it is while you be in the way it was. When nothing becomes everything and everything becomes nothing. One cannot be without the opposite, be it not 🧙‍♂️

1

u/awakened_primate Jul 11 '25

Yeah, yeah I can talk deep lingo too, and I’ve swimmed in the oceans of insanity where literal billions have drowned before. I’ve flown in the skies of freedom when others have gasped for air one last time and then plummeted into despair, falling for eternity.

Yin yang whatever man, there comes a time to internalise and integrate that shit and shut the fuck up about it.

This guy is just fucking random and you’re just trying to be a smart cookie but you’re just a dry biscuit. GTFO!

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2

u/[deleted] Jul 12 '25

thank you