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:

    There are people who are so presumptuous that they know no other way to praise a greatness that they publicly admire than by representing it as a preliminary stage and bridge leading to themselves.
    Friedrich Nietzsche (1844–1900)

    ... there is no such thing as a rational world and a separate irrational world, but only one world containing both.
    Robert Musil (1880–1942)

    Old age equalizes—we are aware that what is happening to us has happened to untold numbers from the beginning of time. When we are young we act as if we were the first young people in the world.
    Eric Hoffer (1902–1983)

    His golden locks time hath to silver turned;
    O time too swift, O swiftness never ceasing!
    His youth ‘gainst time and age hath ever spurned,
    But spurned in vain; youth waneth by increasing.
    Beauty, strength, youth are flowers but fading seen;
    Duty, faith, love are roots, and ever green.
    George Peele (1559–1596)

    A magazine or a newspaper is a shop. Each is an experiment and represents a new focus, a new ratio between commerce and intellect.
    John Jay Chapman (1862–1933)

    What I often forget about students, especially undergraduates, is that surface appearances are misleading. Most of them are at base as conventional as Presbyterian deacons.
    Muriel Beadle (b. 1915)