Generalizing recursion in mapping functions

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Discussion Overview

The discussion revolves around the generalization of recursion in mapping functions, specifically focusing on the mapping function defined as x_{n+1} = \mu (1-x_n). Participants explore conditions under which certain behaviors occur and the challenges of identifying initial conditions that lead to specific outcomes.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant presents a mapping function x_{n+1} = \mu (1-x_n) and identifies a condition for it: x_0 < 1 - \frac{1}{\mu}.
  • Another participant expresses confusion regarding mapping functions with shifts and seeks to understand how to find initial conditions that lead to the defined space.
  • A question is raised about the meaning of "mapping a condition to space," prompting clarification about the specific region defined by the initial condition.
  • There is a discussion about the basin of attraction for the defined region, with one participant questioning whether it truly represents an attractor since it approaches infinity for certain values of mu.
  • Participants express uncertainty about the terminology and concepts related to attractors and the mapping process, indicating a need for clearer definitions and understanding.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the terminology and concepts related to mapping functions and attractors. There are multiple competing views and ongoing confusion regarding the definitions and implications of the conditions discussed.

Contextual Notes

There are unresolved questions about the definitions of terms like "basin of attraction" and "mapping to space," as well as the implications of the mapping function's behavior for different values of mu. The discussion reflects a lack of clarity on how to approach the problem of identifying initial conditions and their relationship to the defined region.

Pythagorean
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I have a mapping function:

[tex]x_{n+1} = \mu (1-x_n)[/tex]

I have some condition that occurs for:

[tex]\mu (1-x_0) > 1[/tex] (1)

which is:

[tex]x_0 < 1- \frac{1}{\mu}[/tex]

but via the map function, there's an initial condition that leads to the above solution:

**UNDER CONSTRUCTION, ERROR FOUND**
 
Last edited:
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Well... "solving" my error just confuses me more. Mapping functions with a shift in them are really unintuitive to me. So, from the top:

Given:

[tex]x_{n+1} = \mu (1-x_n)[/tex]

Some special condition occurs at:

[tex]x_{n+1} = \mu (1-x_n)[/tex]

Which, in terms of initial condition, means that if:

[tex]x_0 < 1- \frac{1}{\mu}[/tex]

than the condition will be met. HOWEVER, there are also initial conditions that will map to the above space. How do I find them? For instance, I can reverse and apply the order of operations in the mapping functions (inverse scale, then shift opposite):

[tex]x_0 < \frac{1- \frac{1}{\mu}}{\mu}+1[/tex]

but this gets unwieldy as I try to go back more and more iterations. Is there an inductive way to represent this "reverse mapping" series as a funciton of n (the number of iterations the mapping function requires). Or am I going about this all wrong?
 
Pythagorean said:
HOWEVER, there are also initial conditions that will map to the above space.

It's unclear what you mean by mapping a condition to space. What space?
 
the region defined by
[tex]x_0 < 1- \frac{1}{\mu}[/tex]
 
I don't understand what you mean by "mapping" the condition to the space since it is the condition that defines the space.

(If your are trying to ask a question about the attractors in the domain of iterated functions, it would be best to use the standard terminology for that subject - or give a link to a page that explains your question.)
 
Well, I am, but I was trying to just focus on the micro-issue I'm having. I just want to find the basin of attraction for that region I defined, but I am not sure if its really an attractor (it goes to infinity; this is the right side of the tent map for mu>2).

Anyway, I will spend more time on it and if I don't get it, I will reformulate the question in more detail later.
 

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