What Makes the Next Generation of Set Theory So Intriguing?

Click For Summary

Discussion Overview

The discussion revolves around the concept of the omniscience principle in the context of constructive mathematics and its implications for set theory. Participants explore interpretations of a specific paper that addresses these topics, seeking to understand its relevance and potential impact on mathematical reasoning.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants express enthusiasm for the paper, suggesting it could broaden perspectives on set theory.
  • Others critique the paper's use of the term "omniscience" as lacking a clear definition, leading to confusion.
  • A participant provides a summary of constructive mathematics, highlighting its limitations compared to classical mathematics and discussing the implications of the law of excluded middle.
  • There is mention of the paper's claim that certain infinite sets satisfy the omniscience principle without violating constructivism, suggesting a potential for constructive mathematics to be more powerful than previously understood.
  • Participants raise questions about the practical implications of the paper, particularly regarding famous unsolved problems like P vs NP and the nature of constructive proofs.
  • Some participants express uncertainty or inability to articulate their thoughts on the paper's significance.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the significance of the omniscience principle or the paper's implications for set theory. There are varying levels of interest and understanding among participants, with some expressing confusion and others attempting to clarify concepts.

Contextual Notes

Some participants reference specific definitions and principles from the paper, but there is a lack of clarity on how these concepts interrelate, and the discussion does not resolve the ambiguities surrounding the omniscience principle and its application in constructive mathematics.

ShellWillis
Messages
5
Reaction score
1
TL;DR
A good read needing confirmation
  • Like
Likes   Reactions: Delta2
Physics news on Phys.org
Omniscience principle? Starting with a profound sounding term with no definition! I stopped reading.
 
  • Like
Likes   Reactions: Klystron and berkeman
I had the same impression, but I’m still interested
 
mathman said:
Omniscience principle? Starting with a profound sounding term with no definition! I stopped reading.
Isn't the definition given in the first sentence of the paper after the abstract?
 
ShellWillis said:
Summary:: A good read needing confirmation

https://www.cs.bham.ac.uk/~mhe/papers/omniscient-journal-revised.pdf

Might be my favorite article I’ve ever came across
I would like to see some interpretations on it to broaden my currently very narrow point of view…

Have fun!
-oliver
Can you explain what you think is interesting about it and why you titled the thread next generation set theory?

The paper is about constructive mathematics.

Constructive mathematics limits what you can say exists to things which you can construct. So it's less powerful than every day mathematics, but it's more intuitive to some people. As an example (based on the slides in the link below).

proposition: There is a program ##p## out there that prints yes if the universe is infinite and no if the universe is finite.

Proof:

case 1: The universe is infinite.

Code:
define p:
    print( yes )

case 2: The universe is finite.

Code:
define p:
    print( no )

In constructive mathematics this is considered cheating and isn't allowed. And the reason we were able to do it is considered to be stemming from the law of excluded middle, according to the slides, which says every proposition is either true or false.

A constructive proof would have to lead to an actual program that can tell us the answer.

https://home.sandiego.edu/~shulman/papers/rabbithole.pdf

The principle of omniscience is talked about here:

In logic and foundations, a principle of omniscience is any principle of classical mathematics that is not valid in constructive mathematics. The idea behind the name (which is due to Bishop (1967)) is that, if we attempt to extend the computational interpretation of constructive mathematics to incorporate one of these principles, we would have to know something that we cannot compute. The main example is the law of excluded middle (EMEM); to apply p∨¬pp \vee \neg{p} computationally, we must know which of these disjuncts hold; to apply this in all situations, we would have to know everything (hence ‘omniscience’).

https://ncatlab.org/nlab/show/principle+of+omniscience

This is my fuzzy take on what the paper is saying.

The paper is about the existence of some kinds of infinite sets that surprisingly have the property that, for those sets, this particular omniscience principle (in the start of the introduction) is satisfied without breaking constructivism. And that somehow shows that a certain branch of constructive mathematics can be more powerful than previously thought, and the excluded middle, which is avoided or restricted because it can break constructiveness, as in the example, can be used in a less restricted way in a variant of constructive mathematics.

This could be interesting in a practical way for all I know, because there are a lot of important questions in mathematics which may be true, but not have constructive proofs. I'm not sure of the implications this paper has in terms of particular problems beyond what's in the paper. But, take for example the famous question: does ##P=NP##? If it is proven true, and the proof is constructive, it could revolutionize computing. If it is proven true, but not with a constructive proof, then the answer is hardly satisfying because we still can't do anything with it.
 
Last edited:
Jarvis323 said:
Can you explain what you think is interesting about it and why you titled the thread next generation set theory?
My thoughts as well...
 
I can’t say
 
  • Skeptical
Likes   Reactions: berkeman
ShellWillis said:
I can’t say
Really? Can't or won't?
 
Thread is closed for Moderation...
 
  • #10
Jarvis323 said:
Can you explain what you think is interesting about it and why you titled the thread next generation set theory?
ShellWillis said:
I can’t say
Since the paper under discussion is in a peer-reviewed journal, this discussion is re-opened provisionally. @ShellWillis you really need to do a better job of leading this discussion. Please respond to the key questions that @Jarvis323 has asked, or the thread will likely be closed permanently. Thank you.
 

Similar threads

  • · Replies 23 ·
Replies
23
Views
5K
  • · Replies 5 ·
Replies
5
Views
18K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 42 ·
2
Replies
42
Views
5K
  • · Replies 2 ·
Replies
2
Views
5K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 25 ·
Replies
25
Views
6K
  • · Replies 13 ·
Replies
13
Views
10K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 19 ·
Replies
19
Views
4K