TheBestLinks.com
TheBestLinks.com
Dyadic fraction, Dyadic rational, Abelian group, Dense, Egypt, Integer, Inverse ... Print friendly version | Tell a friend
 
Navigation
Search
Toolbox

Dyadic rational

From TheBestLinks.com

(Redirected from Dyadic fraction)

In mathematics, a dyadic fraction or dyadic rational is a rational number that when written as a fraction has denominator a power of two, i.e. a rational number of the form a/2b where a is an integer and b is a natural number. (Like fractions of an inch as commonly used in the US, for instance) These are precisely the numbers whose binary expansion is finite. The set of all dyadic fractions is dense in the real line; it is a rather "small" dense set, which is why it sometimes occurs in proofs, see for instance Urysohn's Lemma. The dyadic fractions form a subring of Q.

what properties does this ring have?

The surreal numbers are generated by an iterated construction principle which starts by generating all finite dyadic fractions, and then goes on to create new and strange kinds of infinite, infinitesimal and other numbers.

The ancient Egyptians used Horus-eye notation for dyadic fractions.

Dyadic solenoid

As an abelian group the dyadic rationals are the direct limit of infinite cyclic subgroups

2nZ

for n = 0, 1, 2, ... . In the spirit of Pontryagin duality, there is a dual object, namely the inverse limit of the unit circle group under the repeated squaring map

ζ → ζ2.

The resulting topological group D is called the dyadic solenoid. As a topological space it is an indecomposable continuum.


Related links


Top visited 0 of 0 links

[no links posted yet]

>> place link >>

Discussion

Last posted 0 of 0 messages

[no messages posted yet]

>> post message >>

Watch

You can add this article to your own "watchlist" and receive e-mail notification about all changes in this page.
 
   
Innovate it
This page was last modified 17:25, 21 Sep 2004.
  Content is available under GNU Free Documentation License 1.2.
Powered by MediaWiki