Monad (non-standard analysis)

From Wikipedia, the free encyclopedia

In non-standard analysis, a monad (also called halo[1]) is the set of points infinitely close to a given point.

Given a hyperreal number x in R*, the monad of x is the set

{\text{monad}}(x)=\{y\in {\mathbb  {R}}^{*}\mid x-y{\text{ is infinitesimal}}\}.

If x is finite (limited), the unique real number in the monad of x is called the standard part of x.

See also

Notes

  1. Goldblatt, Robert (1998). Lectures on the Hyperreals. Berlin: Springer. ISBN 0-387-98464-X. 

References

This article is issued from Wikipedia. The text is available under the Creative Commons Attribution/Share Alike; additional terms may apply for the media files.