Can we ever construct a perfect circle? (Curiousity)

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Homework Help Overview

The discussion revolves around the feasibility of constructing a perfect circle, touching on concepts from geometry and philosophical paradoxes, particularly Zeno's paradox and the nature of infinity.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore definitions of "perfect" and the implications of Zeno's paradox on the construction of geometric shapes. Some question the relevance of infinite processes in practical constructions, while others discuss the limitations imposed by specific geometric tools.

Discussion Status

The conversation is ongoing, with various interpretations of what constitutes a perfect circle being examined. Some participants have offered insights into geometric constructions and the constraints of traditional methods, but no consensus has been reached.

Contextual Notes

There is mention of specific geometric constructions allowed, such as using a compass and ruler, and the implications of these rules on the ability to create certain polygons, which may influence the discussion on circles.

icystrike
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Homework Statement


As stated abv.

Since [tex]\pi[/tex] can only be established by infinite sum and according to zeno's paradox we can never break a finite length into infinite pieces (loosely speaking)
 
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Depends on your definition of perfect. It's like getting from Point A to Point B. That paradox states we can't get from A to B because we always have to cover half the remaining distance. That's not a good excuse to tell your boss why you were late, I've found out.
 
Based on the title of your thread, no, we can't construct a perfect circle. The circle of geometry is an idealized object, every point of which is the same distance away from the center. The curve that makes up the circle is infinitessimally thin, so there's no way we can draw it.

icystrike said:
Since [itex]\pi[/itex] can only be established by infinite sum and according to zeno's paradox we can never break a finite length into infinite pieces (loosely speaking)[/itex]
I don't understand what this has to do with your question.
??
 
Like everyone else said, it depends what you're "allowed" to do. A common construction people use is an "infinite" ruler and a compass. Basically, you start with two arbitrary points in R-2 space, say (0,0) and (1,0). The only operations you're allowed to make are circles with the center at one point and the circumference on another point, and lines through two points. Any intersections you get are considered new points.

Knowing this, it's actually been proven that you cannot construct a 7-gon with with this construction. However, it has been proven that you can construct a 17-gon! (The construction is messy as hell) But to answer your question, it just depends what operations you're allowed to make.
 

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