Image 19
Model: The Distribution of All Rational Numbers
or Musical Intervals on the Monochord
Conceived and drawn by Peter Neubäcker
In
order to investigate how all fractions, or rational numbers, are
distributed, one can divide segments of a unit of length-here the
monochord string-progressively by all the fractions, and mark the place
of the division with a line. For example, one could begin with the
number 2 and mark half of the length, then 1/3 and 2/3, then 1/4, 2/4, 3/4, then 1/5, 2/5, 3/5, 4/5,
and so forth. The result is represented by the drawing, placed over the
monochord-here all fractions are plotted up to index 100. For
clarification, the lines are of different lengths: the smaller the
number, the longer the line that indicates the ratio produced by it.
In this process a very interesting structure is revealed: the smaller
the number from which the interval in question is constructed, the more
space is left to it from the following ratios-so the degree of
consonance of the interval can be determined directly from the width of
the gaps that appear in the illustration.
The string itself also conforms to this pattern in its vibrations: the
wider the in-between space in the drawing, the more pronounced is the
vibration point at this location, responsible for producing the
respective overtone. This can be tested by moving the rubber disc back
and forth on the string and plucking the string as near as possible to
one of the two nuts; the rubber disc stops the string from vibrating at
the place in question, and thus sets a vibration point so that the
corresponding overtone will sound. Thus one can establish that there
are some overtones at almost every point, which sound with greater or
lesser strength-but coming near to one of the large gaps in the
drawing, one enters the “catchment area” of a small number, and the
corresponding stronger tone overwhelms the others, which are manifested
through higher numbers. One could say that the numbers have an
“attractive power,” which is stronger when the number is smaller.
Besides the musical properties, a plethora of other applications lie
hidden in this illustration-Rudolf Stössel examined these structures
more closely-with concepts appearing such as symmetry, isolation,
reproduction, the rule of addition, the product law, and connections
with the Fibonacci Sequence and its relatives, i.e. the Golden Section,
the Lambdoma, and crystals.
Peter Neubäcker

Image 20
The Distribution of All Rational Numbers
or Musical Intervals in Circular Form
Conceived and drawn by Peter Neubäcker
Not
only can the arrangement of all fractions or musical intervals be
illustrated in quadratic form, as with the model of the Lambdoma (Image
14)-a circular arrangement is also possible. For this, the entire
circle is defined as the unit; the fractions are marked off as
fractional parts of the whole round angle. Fractions with the same
numerator are on the same circle-each circle therefore corresponds to a
perpendicular line in the quadratic Lambdoma. Up to index 8, this
arrangement emerges:
Tones with the same value, i.e. fractions that can be cancelled down,
are always on the same line, which leads outwards radially. These
“equal-tone lines” are also plotted here. Image 20 shows only these
equal-tone lines, each drawn from their origin outwards-here for all
fractions up to index 100.
While the values with the same numerator-corresponding to the undertone
series-always lie upon concentric circles, the values with the same
denominator form spirals, corresponding to the overtone series, and all
finally run parallel to the generator-tone line.
Here the same phenomenon can be observed as was seen in the positioning
of the fractions on the monochord (Image 19): the fractions are divided
unequally in favor of the smaller numbers or the more consonant
intervals. This can be thought of as a hierarchy in the world of
numbers, or an “aristocracy of small numbers.”

Image 21
The Distribution of All Rational Numbers
Above: Image 20 reflected inwards
Below: magnification of the inner space
Conceived and drawn by Peter Neubäcker
The
round Lambdoma illustration actually only contains half of the values
of the quadratic Lambdoma, namely all true fractions in the domain
between zero and one. Their reciprocals, which would correspond in the
model in Image 19 to a lengthening of the unit string, are only present
latently: if the circles in the round illustration are understood as
“bent strings,” then all values above one can be represented in this
way. The circumference of the second circle is exactly twice that of
the unit circle, the third three times as long, and so on. Thus, for
example, the equal-tone line 1/3 marks off the length 4/3 on the fourth
circle, the length 5/3 on the fifth, etc. In this representation, the
true fractions are realized by means of the angles, and their
reciprocal values through the circle arcs.
Image 21 shows another way to illustrate the reciprocal values in the
round Lambdoma: through reflection on the unit circle. These images
must be imagined as tiny circles at the center of Image 20: All rays
going out from Image 20 go inwards here, and their origin corresponds,
in each case, to the reciprocal value of the point on the outside. The
lower image shows a large magnification of the upper one, and moreover
the fractions here are not represented by rays (equal-tone lines) but
only by points; all reducible fractions are thereby discarded. An
infinite number of values go inwards-these images can be seen as a
symbol of the potential endlessness in the spiritual domain, which is
expressed as true unending multitude after transcending the unit circle
in Image 20.
22
(No image here)
Three-Dimensional Model of the Distribution of Fractions
Corresponds to the Scheme of Image 20
Model conceived and built by Peter Neubäcker

Image 23
The Distribution of the Prime Numbers up to 30000
Above: From the viewpoint of the number 210 (2 × 3 × 5 × 7)
Below: From the viewpoint of the number 211 (prime number)
Conceived and drawn by Peter Neubäcker
This
and the two following images relate to the distribution of the prime
numbers. The first question to be asked here is, what does a problem of
number theory such as the distribution of prime numbers have to do with
harmonics in the narrower sense?
The musical intervals are built from numbers-thus intervals that are
built from the same prime numbers are closely connected with each
other. The first interval-building number is two-it only ever leads to
octaves. The next is three-the entire series of fifths can be built
from it, which actually leads to an endless supply of tones, consisting
only of fifth ratios. Until the Renaissance, this was the only tone
structure used in the Western world. Then the prime number five emerged
in music as the next step, leading to a more complex supply of tones,
which includes harmony structures through the relationships of thirds
in the sense of triads. In modern times the next prime number, seven,
is also applied; but at present, its musical potentials have hardly
been explored or integrated.
In studying harmonics, the entire world of numbers becomes a symbolic
image for the world, in which each number plays its specific role-this
role can be explored through the factorization of all numbers, which
always leads to the prime numbers and thus reveals the relationships of
the numbers. By listening to these numbers, one can also approach their
nature more closely through perception. This is harder with the higher
prime numbers, since for cultural reasons no specific musical
experience is yet connected with them. But since all prime numbers
manifest qualities with their own character in the world of numbers,
their distribution is of interest in principle.
The distribution of the prime numbers is irregular. No mathematical law
has yet been discovered with which prime numbers can be clearly
predicted-probably no such law can be found-but certain structures in
their distribution can be determined. Such structures are illustrated
from various viewpoints in the image shown. Images 23 and 24 show the
distribution of prime numbers from the “viewpoint” of individual
numbers-mathematically expressed, the arrangement is the “module of a
given number.”

Image 24
The Distribution of Prime Numbers up to 10000
from the Viewpoint of the Numbers 200 to 228
(in increments of 0.2)
Conceived and drawn by Peter Neubäcker
When
all natural numbers are arranged so that they lie upon concentric
circles, and the same quantity of numbers is on each circle, then the
number of rays emerging corresponds to the number used as a basis. For
the numbers 11 and 12, for example, these two images would be produced:
The
prime numbers here are indicated by circles. Thus it is shown that for
the number 12, prime numbers can only lie upon four of the 12 rays,
since all numbers on the second ray are divisible by two, all on the
third are divisible by three, all on the fourth are divisible by four,
and so on-because these numbers are factors of 12. For the image of the
number 11, on the other hand, prime numbers can lie on all rays (except
for the 11th
ray, on which all numbers are multiples of 11) , since 11 itself is a
prime number. If the composite numbers are removed and only the prime
numbers left, these images result for 11 and 12:
From
the viewpoint of the number 12, the prime numbers appear very orderly,
but from the viewpoint of 11 completely disorderly. In this manner
Images 23 and 24 emerge for higher numbers: the number 210, as a
product of 2 × 3 × 5 × 7, puts the numbers in order to a very high
degree, but the adjacent number 211 is a prime number which generates
no order in itself; instead the order of the number 210 still appears
here. Image 24 shows that every number has its own “face”-partly
generated of itself, partly shaped by its neighbors.

Image 25
The Distribution of the Prime Numbers According to the Pythagorean Polarity
of Square Numbers and Rectangular Numbers
Above: numbers up to 2500
Below: numbers up to 100000
Conceived and drawn by Peter Neubäcker
The
ordering principle of this image is different from those of the two
previous images: for the Pythagoreans, polarity was a central concept,
and they counted ten such polarities, so that concepts emerged such as
limited and unlimited, odd and even, male and female, etc. The tenth of
these polarities is the opposition of square and rectangular numbers.
Why precisely these two concepts should be polarities was not entirely
understandable. But when these polarities are arranged in terms of all
numbers, it becomes clear that this arranges the prime numbers to the
highest degree. In the images shown here, all natural numbers are
arranged in a spiral, so that in each revolution a square number is
encountered-thus the series of rectangular numbers appears precisely on
the opposite, i.e. the numbers that are the product of two consecutive
numbers, such as 6 = 2 × 3, 12 = 3 × 4, 20 = 4 × 5, etc. In the upper
image, all numbers up to 2500 are shown, and the prime numbers are
indicated by white circles. In the lower image the numbers up to 100000
are shown; the composite numbers are omitted here, and only the prime
numbers indicated by white dots.
Thus it can be seen that all prime numbers arrange themselves in
curves, which approach lines parallel to the ray of the rectangular
numbers. In each case such a ray represents the sum of a given number
with all rectangular numbers, and can therefore be represented by the
expression (n × [n + 1]) + m. For certain values of m, an especially
large quantity of prime numbers is yielded, e.g. for m = 17 or even
more for m = 41. The expression n × (n + 1) + 41 has already been
described by Leonhard Euler as an especially fruitful prime number
formula.
The numbers 17 and 41 are prime numbers themselves-so it can be said
that prime numbers that generate many new prime numbers are especially
“fruitful.”
It is unlikely that the prime number-ordering function of this polarity
was known to the Pythagoreans-it more likely emerged from the finding
that the square numbers are always sums of all odd numbers and the
rectangular numbers are always sums of all even numbers-but here it can
be seen again that the truth is always found in testimonies from many
different levels at the same time.