Closed Intervals with Infinite Endpoints: Explained

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SUMMARY

The discussion centers on the properties of closed intervals with infinite endpoints, specifically the intervals (-∞, b] and [a, ∞). Participants argue that these intervals are closed because they contain all their limit points. The conversation highlights the definitions of closed sets in real analysis, emphasizing that sequences converging within these intervals must converge to points within the intervals themselves. The debate also touches on the implications of using infinity in mathematical contexts, asserting that symbols like +∞ and -∞ serve as notational conveniences rather than actual real numbers.

PREREQUISITES
  • Understanding of closed sets in topology
  • Familiarity with real analysis concepts, particularly limits and sequences
  • Knowledge of interval notation and its implications in mathematics
  • Basic grasp of the real number system and its extensions
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  • Study the properties of closed sets in topology, focusing on real numbers
  • Learn about the concept of limit points and their significance in analysis
  • Explore the implications of using extended real numbers in mathematical proofs
  • Investigate the differences between open and closed intervals in various mathematical contexts
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Mathematicians, students of real analysis, and anyone interested in the foundational concepts of topology and interval properties in mathematics.

  • #121
The rule is symmetry.

If {} then {__}.
 
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  • #122
Is that giving an example? Did I not explain sufficiently what example means?

That propostion above does not make sense.
First rule of writing mathematics: all sentences should be sentences.

We appear to have established that {__}, actual infinity, ONE, is the North Pole of the Riemann Sphere. Is this correct? The last of these isn't a set. Does that matter? It is also an infinitely long object, but I think this is you using long in some undefined way. How can a point have length?

I think you need to differentiate in your mind between the empty set and zero, and infinity as a point lying further away from zero than all real (complex) numbers and infinite meaning not finite. You appear to be comparing two different concepts.

In that vein, try explaining how your infinity {__} is related to cardinality. How does it relate to, say, infinite dimensional vector spaces.

Now why is it important to find an injection between this point at infinity and say R?

I think you should start a new thread to go through this from the beginning because it is getting too complicated with all these different topics. So start one about the New Diagonal Argument and we'll sort that out shall we?
 
  • #123
Dear Matt,

Thank you for your advice.

Your model is about point, but not mine.

If you read my papers (and you don't) for example:

http://www.geocities.com/complementarytheory/CompLogic.pdf

http://www.geocities.com/complementarytheory/4BPM.pdf

You will find my very simple definition to continuum (or fullness) which is clearly separated from any point model.

Also if you read this:

http://www.geocities.com/complementarytheory/Everything.pdf

Where I clearly and simply distinguish between ONE(={__})
and one of many(={.}) .
 
  • #124
I have read your articles. They are not very clear in what you are trying to express.

You have said that {__} is the point at infinity on the Riemann Sphere, or that it represents it in some posting mentioning RiemannsBall.pdf

the cardinality of {__} in your universe is 1, for instance, it is also decribed as an infinitely long line.

Try putting some more words in your articles so that you explain how the deductions you've made have been arrived at, as they currently read like a bunch of unmotivated random assertions from someone who can't understand maths properly.
 
  • #125
Again, there is no objective Math that you understand it or not, all what we have is a rigorous agreement based on language.

You cannot understand my work because you think 2D, and my system is fractalic multi-D and Non-Euclidean.

One of its first results is the difference between multiplication and addition, and their complement associations, which are some of the fundamentals of my number system.

If you did not see it until know, and you are totally closed in your 2d point of view, which is the Euclidean-Mathematics point of view.
 
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  • #126
That's a rather strange attitude to take. I don't understand your math because of its paucity of intellectual content and inability to be self-consistent or explicable. One of the things you've said is that it isn't necessary to be rigorous, and you've repeatedly demonstrated that by refusing to answer questions and explain what's going on, write your ideas out clearly in this forum, define anything from first principles, pay even the slightest attention to conventions and already extant notions/notations.


In fact I can't think of one question you've ever answered to the satisfaction on the questioner.

Here are some outstanding ones:

what does it mean for a set to be too strong to be measured?

explain the inductive process you use to create the list of 01 combinations and prove that it is complete (except for ...111)

is {__} a set or a proper class? what are some of its elements?

explain what you mean by 1-1 map because it is apparent that you believe there are no 1-1 maps from an infinite set to itself that are also surjections.

define opposite

what is the mathematical meaning of fullness?

how can an inequality be equal the the empty set, or a set containing as an element an inequality (whether it is valid or not) be equal to the empty set?

in what way is aleph-0 probabilistic?

take as many words to explain these as possible. don't post pdfs. As you are posting in a public forum one presumes you are attempting to explain to people what you believe (and that you think it worthwhile sharing), so it seems ony fair to explain everything properly; how can people be expected to understand it otherwise.
 
  • #127
Dear Matt,

Your world is (0 XOR 1).

My world is fading transition between (0 XOR 1) and (0 AND 1).

Your world is a private case of my word.

I cannot translate my definitions to your world for example:

Because your logical world is limited to 2D (0 XOR 1) and my world is not limited to 2D logic, when you ask me to define my system in terms of your logical 2D word, I hope that you understand that when it is translated, her point of view is lost.

So, instead of continuing these useless replies between us, I am going to open a new thread, and the I'll ask the members to show us what is the difference between multiplication and addition by using Boolean logic.
 
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  • #128
Organic, I would suggest that you are a megalomaniac, but I'm afraid that you'll just make up your own definition of what "megalomaniac" means and it'll become a complement.

Perhaps your world would be more meaningful if it tooks concepts from our world such as "consistency" and "coherence". Those things have done wonders in our world.


Perhaps if you start connecting to the Internet with a computer built on principles of Complimentary logic instead of Boolean logic, your credibility will increase. Building such a device should be a simple task for one with an intellect such as yours.
 

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