Golden Ratio Base - Representing Rational Numbers As Golden Ratio Base Numbers

Representing Rational Numbers As Golden Ratio Base Numbers

Every non-negative rational number can be represented as a recurring base-φ expansion, as can any non-negative element of the field Q = Q + √5Q, the field generated by the rational numbers and √5. Conversely any recurring (or terminating) base-φ expansion is a non-negative element of Q. Some examples (with spaces added for emphasis):

  • 1/2 ≈ 0.010 010 010 010 ... φ
  • 1/3 ≈ 0.00101000 00101000 00101000... φ
  • √5 = 10.1φ
  • 2+(1/13)√5 ≈ 10.010 1000100010101000100010000000 1000100010101000100010000000 1000100010101000100010000000 ...φ

The justification that a rational gives a recurring expansion is analogous to the equivalent proof for a base-n numeration system (n=2,3,4,...). Essentially in base-φ long division there are only a finite number of possible remainders, and so once there must be a recurring pattern. For example with 1/2 = 1/10.01φ = 100φ/1001φ long division looks like this (note that base-φ subtraction may be hard to follow at first):

.0 1 0 0 1 ________________________ 1 0 0 1 ) 1 0 0.0 0 0 0 0 0 0 0 1 0 0 1 trade: 10000 = 1100 = 1011 ------- so 10000-1001 = 1011-1001 = 10 1 0 0 0 0 1 0 0 1 ------- etc.

The converse is also true, in that a number with a recurring base-φ; representation is an element of the field Q. This follows from the observation that a recurring representation with period k involves a geometric series with ratio φ-k, which will sum to an element of Q.

Read more about this topic:  Golden Ratio Base

Famous quotes containing the words representing, rational, numbers, golden, ratio and/or base:

    ... today we round out the first century of a professed republic,—with woman figuratively representing freedom—and yet all free, save woman.
    Phoebe W. Couzins (1845–1913)

    So far as discipline is concerned, freedom means not its absence but the use of higher and more rational forms as contrasted with those that are lower or less rational.
    Charles Horton Cooley (1864–1929)

    Our religion vulgarly stands on numbers of believers. Whenever the appeal is made—no matter how indirectly—to numbers, proclamation is then and there made, that religion is not. He that finds God a sweet, enveloping presence, who shall dare to come in?
    Ralph Waldo Emerson (1803–1882)

    He, that holds fast the golden mean,
    And lives contentedly between
    The little and the great,
    Feels not the wants that pinch the poor,
    Nor plagues that haunt the rich man’s door,
    Imbitt’ring all his state.
    Horace [Quintus Horatius Flaccus] (65–8)

    People are lucky and unlucky not according to what they get absolutely, but according to the ratio between what they get and what they have been led to expect.
    Samuel Butler (1835–1902)

    When a man speaks the truth in the spirit of truth, his eye is as clear as the heavens. When he has base ends, and speaks falsely, the eye is muddy and sometimes asquint.
    Ralph Waldo Emerson (1803–1882)