MHB Actual infinity vs. potentially infinity - Math philosophy

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The discussion centers on the distinction between actual infinity and potential infinity in mathematics, emphasizing that the debate is philosophical rather than rooted in physical limitations. Actual infinity refers to a completed set, while potential infinity describes a process that can continue indefinitely without reaching completion. Participants note that many mathematicians accept actual infinities, which contrasts with misconceptions that tie the concept to physical realities. The conversation also highlights that mathematical discussions should focus on abstract structures rather than physical representations. Understanding these differences is crucial for grasping foundational mathematical concepts.
highmath
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what the differences between actual infinity to potentially infinity?
 
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Have you searched for this? I get a wiki-article, some articles (scholarly and otherwise) and a few videos that claim to provide explanations.
(For example, to my relief, I just learned from this that I apparently side with the majority of mathematicians that "accept actual infinities".)

If you have a more specific question, I am quite sure there are more capable people here to answer it.

Note: I think one of the confusions that often appears in such discussions, is that people oppose the actually infinite on the grounds of limitations imposed by physical reality. This is not correct: Rather, the discussion does not depend on physical, but philosophical and foundational constraints.
 
Janssens said:
Have you searched for this? I get a wiki-article, some articles (scholarly and otherwise) and a few videos that claim to provide explanations.
(For example, to my relief, I just learned from this that I apparently side with the majority of mathematicians that "accept actual infinities".)

If you have a more specific question, I am quite sure there are more capable people here to answer it.

Note: I think one of the confusions that often appears in such discussions, is that people oppose the actually infinite on the grounds of limitations imposed by physical reality. This is not correct: Rather, the discussion does not depend on physical, but philosophical and foundational constraints.
I don't understand the bold and underline texts.
Can you explain it?
 
highmath said:
I don't understand the bold and underline texts.
Can you explain it?

Physical quantities such as mass and velocity have a finite magnitude. (In the case of velocity, there is even a particular upper bound.) However, this is not relevant in the context of "actual vs. potential infinity", because in that context we are concerned with sets as abstract mathematical structures, not as representations of the values of physical quantities.
 
I find a quote from Dedekind somewhat apropos: "If space has at all a real existence it is not necessary for it to be continuous; ... And if we knew for certain that space was discontinuous there would be nothing to prevent us, in case we so desired, from filling up its gaps, in thought, and thus making it continuous;"

Dedekind, "Continuity and Irrational Numbers" in "Essays On the Theory of Numbers"; translation by Wooster Woodruff Beman.
 
I have been insisting to my statistics students that for probabilities, the rule is the number of significant figures is the number of digits past the leading zeros or leading nines. For example to give 4 significant figures for a probability: 0.000001234 and 0.99999991234 are the correct number of decimal places. That way the complementary probability can also be given to the same significant figures ( 0.999998766 and 0.00000008766 respectively). More generally if you have a value that...

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