Is the Fractal Perimeter Infinite but Area Finite?

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Discussion Overview

The discussion revolves around the properties of the Koch Snowflake fractal, specifically addressing the question of whether it has an infinite perimeter while maintaining a finite area. Participants explore mathematical series, convergence, and the implications of fractal geometry.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant suggests that the Koch Snowflake's infinite perimeter could converge to a finite number due to the diminishing contributions of each iteration, drawing parallels to a converging series.
  • Another participant counters that not all series with terms approaching zero converge, using the harmonic series as an example, and argues that the perimeter actually increases with each iteration of the Koch Snowflake.
  • A participant acknowledges that while each triangle added contributes less to the perimeter, the number of triangles increases, complicating the convergence argument.
  • One participant expresses amazement at the properties of the Koch Snowflake, noting its infinite perimeter and finite area, and inquires about equations for other fractals.
  • Another participant clarifies that the perimeter is not "inside" the area of the fractal, suggesting a misunderstanding of the spatial relationship between the two.
  • A later reply indicates that the original statement about the perimeter being "inside" the area was meant to refer to a surrounding square, not the area of the fractal itself.

Areas of Agreement / Disagreement

Participants exhibit disagreement regarding the convergence of the series related to the Koch Snowflake's perimeter. While some argue for the possibility of convergence, others assert that the perimeter diverges. The discussion remains unresolved with multiple competing views presented.

Contextual Notes

There are limitations in the discussion regarding the assumptions about series convergence and the definitions of perimeter and area in the context of fractals. The mathematical steps involved in the series calculations are not fully explored.

Gib Z
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Hey if you guys look up Fractal on Wikipedia, you see the author states that the Koch Snowflake, a common and famous fractal, supposedly has an infinite perimeter yet finite area. It sed it would be infinite perimeter because it keeps on adding perimeter with each iteration. How ever, i thought since it keeps on adding Less with each iteration, it would remsemble a series that continually adds less. i haven't worked out the actual series yet, i will soon, but basically since it keeps adding less and less, it should eventually converge into a finite number eventually, right? sort of like if u kept on adding 10^0 + 10^-1 + 10^-2 + 10^-3 + 10^-4 so on so forth, sure u keep adding numbers, but the first one is 1, 2nd term 0.1, 3rd 0.01, 4th in 0.001, so on in that fashion, adding to 1.11111111111111111111111..., or 1 and 1/9. well yea, so this fractal i think really had finite area
 
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Not all series which have terms that go to zero converge. For example,

\sum_{n=1}^\infty \frac{1}{n} = \infty

To see this, note:

1+ \frac{1}{2} + \left(\frac{1}{3} + \frac{1}{4} \right) + \left(\frac{1}{5} + \frac{1}{6} + \frac{1}{7} +\frac{1}{8} \right) + ... > 1 + \frac{1}{2} + \left( \frac{1}{4} + \frac{1}{4}\right) + \left( \frac{1}{8} +\frac{1}{8} +\frac{1}{8} +\frac{1}{8} \right) + ... = 1 + \frac{1}{2} +\frac{1}{2} + ... = \infty

But this doesn't matter here, because in the Koch snowflake, at each step you increase the perimeter by 4/3, so the terms in the series actually increase, and so it obviously diverges.
 
Last edited:
Gib Z said:
How ever, i thought since it keeps on adding Less with each iteration, it would remsemble a series that continually adds less.
It is true that each triangle part adds less per iteration but at the same time there are more of them per iteration. :smile:
 
yea that's for the help, i just realized wen i actually bothered to work it out this morning. wow that is quite extra ordinary, infinite perimeter inside a finite area. does anyone know the equations of any fractals, hopefully that i can plug into Graphamatica 2.0e?
 
Well, no, the perimeter is NOT "inside" the area!
 
excuse me? yes i think quite so. I was no referring to inside the finite area of the fractal, but say, a square around it.
 

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