Understanding the Heine Borel Theorem: An In-Depth Analysis

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Discussion Overview

The discussion centers around the Heine Borel Theorem, specifically addressing the conditions under which certain sets have finite subcoverings. Participants explore the implications of definitions and notation related to the theorem, as well as the reasoning behind specific claims made in a proof.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Homework-related

Main Points Raised

  • One participant questions why it is necessary to show that gamma equals beta, suggesting that if gamma is the supremum of F, it must be greater than beta to avoid S containing H_squiggly_bar.
  • The same participant asks why S_gamma+eps does not have a finite subcovering, seeking clarification on which definition the author refers to.
  • Another participant points out that the notation used needs to be defined for clarity, indicating a potential barrier to understanding the discussion.
  • A later reply expresses difficulty in reading attachments due to type size and notes that H_i is not defined, which may hinder the analysis presented.

Areas of Agreement / Disagreement

Participants express uncertainty regarding the definitions and implications of the theorem, with no consensus reached on the correctness of the proof or the specific questions raised.

Contextual Notes

Limitations include undefined notation and potential ambiguities in the definitions referenced in the discussion, which may affect the clarity of the arguments presented.

kidsasd987
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Hello, I have a question about Heine Borel Theorem.

First, I am not sure why we have to show
"gamma=Beta"
gamma is the supremum of F(which is equivalent to H_squiggly_bar in the text ), and it has to be greater than beta. Otherwise, S contains H_squiggly_barSecond, for the case 1, why S_gamma+eps does not have a finite subcovering? which definition the author is referring to?

I understand sup(F) = gamma, so S_gamma-eps must have a finite subcovering because by definition H_squiggly_bar is a set of finite subcovering. But isn't there a possibility that S_gamma+eps also has a finite subcovering?

That consists of H_squiggly bar + some finite set that belongs to H but not contained within H_squiglly bar?
 

Attachments

  • 스크린샷 2016-07-11 5.45.36 PM.png
    스크린샷 2016-07-11 5.45.36 PM.png
    94.4 KB · Views: 714
  • 스크린샷 2016-07-11 5.45.30 PM.png
    스크린샷 2016-07-11 5.45.30 PM.png
    76.5 KB · Views: 654
  • Heine_Borel_Theorem.png
    Heine_Borel_Theorem.png
    31.1 KB · Views: 1,543
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Without the text, the notation you use needs to be defined.
 
mathman said:
Without the text, the notation you use needs to be defined.

I am sorry. This is the updated version. Do you think the proof is right? and what do you think of the question at the end?
 

Attachments

  • Heine_Borel_2.png
    Heine_Borel_2.png
    28.9 KB · Views: 633
I am finding these attachments hard to read (type size). In the latest attachment, much of the analysis makes use of H_i, which is not defined.
 

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