What is the opposite of epsilon

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    Epsilon Infinite Zero
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Discussion Overview

The discussion revolves around the concept of finding a notation or term that represents the opposite of epsilon (infinitesimal), similar to how infinity is considered the opposite of zero. Participants explore various interpretations of "opposite" and suggest potential symbols or terms.

Discussion Character

  • Debate/contested

Main Points Raised

  • Some participants propose that there is no definitive term for the opposite of epsilon, suggesting alternatives like "immeasurable" or "infinite."
  • It is noted that for every ##\varepsilon > 0##, its reciprocal ##\varepsilon^{-1} = \frac{1}{\varepsilon}## is considered "very big," but no preferred symbol exists to denote this.
  • Some participants mention that capital letters, such as ##H## or ##N##, are commonly used to represent large values related to epsilon.
  • There is a suggestion that ##N## could stand for "number" in expressions like ##N(ε)##, while ##C## might represent a constant.
  • A quote from Paul Halmos is shared, humorously referencing the complexity of sequences involving epsilon that tend to infinity.
  • One participant revisits the original question, asserting that the opposite of infinity is epsilon, and discusses the definitions of "opposite" in terms of additive and multiplicative inverses.
  • It is argued that if "opposite" refers to additive inverse, then ##-\infty## would be the opposite of ##\infty##, and ##-\varepsilon## for ##\varepsilon##; however, if it refers to multiplicative inverse, then the opposite of ##\varepsilon## would be ##\infty##.
  • There is a mention that zero does not have a multiplicative inverse, leading to the idea that it may not have an opposite.

Areas of Agreement / Disagreement

Participants do not reach a consensus on a specific notation or term for the opposite of epsilon, and multiple competing views on the interpretation of "opposite" remain present throughout the discussion.

Contextual Notes

The discussion highlights the ambiguity in defining "opposite" in mathematical terms, particularly in relation to infinitesimals and infinity, and the lack of universally accepted symbols for these concepts.

Pjpic
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Is there a notation for the opposite of epsilon (infinitesimal) in the way that infinity is the opposite of zero?
 
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I don't think there is a definitive term, I've seen people use these terms:
- immeasureable
- infinite
 
For every ##\varepsilon >0## ''very small'' you have ##\varepsilon^{-1}=\frac{1}{\varepsilon}## is ''very big'', in general there is no a preferred symbol to denote this ...
 
Usually, people like to use capital letters for this, such as ##H## or ##N##.
 
Perhaps ##N## for number such as ##N(ε)##. I've also seen ##C## for a constant. But I've never seen a huge ##H##.
 
"The nightmare of mathematician is a sequence ##\varepsilon_n## that tends to infinity, as ##n \to 0##"
Paul Halmos
 
Pjpic said:
Is there a notation for the opposite of epsilon (infinitesimal) in the way that infinity is the opposite of zero?
The opposite of infinity is not zero, it's ##\varepsilon##.
Source : This Numberphile video

.
Depends how you define "opposite". If you mean additive inverse, then ##-\infty## would be the opposite of ##\infty##, and ##-\varepsilon## for ##\varepsilon##. If by "opposite" you mean multiplicative inverse, then the opposite of ##\varepsilon## would be ##\infty##. Zero, on the other hand doesn't have a multiplicative inverse, so maybe we can say it doesn't have an opposite.
 

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