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Spirals, and Similarity Symmetry

2 or 2i, or the normal of a symmetry plane, m or a, with one of the coordinate axes is indicated by placing the symbol of this element in the corresponding position in the notation. [Pg.381]

We have stressed above the necessity of considering our objects extending to infinity at least in one direction in order to qualify [Pg.381]

A screw axis brings the infinite rod into coincidence with itself after a translation through a distance t accompanied by a rotation through an angle a. The screw axis is of the order n = 360°/a. It is a special case when n is an integer. The iron chain and the beryllium dichloride chain have a fourfold (or fourth-order) screw axis, 42. Their overall symmetry is (a) m 42 m. For the screw axis of the second order, the direction of the rotation is immaterial. Other screw axes may be either [Pg.382]

Whereas helical symmetry is characterized by a constant amount of translation accompanied by a constant amount of rotation, in spiral symmetry the amounts of translation and rotation change gradually and regularly. D Arcy Thompson capitalized this word in his description,. . a Spiral is a curve which, starting from a point of origin, [Pg.391]

A gradual and regular change in size may appear by itself, that is, without being part of a spiral. A regular change in size characterizes, for example, homologous series, such as the alkanes, C H2 +2, [Pg.393]

Very little is known about the origin of phyllotaxis. What has been noted a long time ago is that the numbers occurring in these characteristic ratios, viz., [Pg.350]

Fiuure 8-17. Two representations of the double helix of a deoxyribonucleic acid molecule, after Ref. [8-9], [Pg.354]


These steps are represented by the index n in Table 5.4. Each value of n represents an allowed orbital distance for a satellite from its parent attractor. The planets have indices of Neptune(O), Uranus(2), Saturn(6), Jupiter(9), Asteroids(12), Mars(15), Earth(18), Venus(21) and Mercury(24). Because of the self-similar symmetry of the golden spiral this progression can be continued indefinitely on a continuously increasing scale. [Pg.160]

The demonstration that the solar system displays the same self-similar symmetry, also noticed in the image of spiral galaxies and hurricanes, makes it hard to deny that the pattern conveys more than coincidence. It probably is one of the more rehable guides towards a better imderstanding of the natural world. [Pg.300]

C5HuN05 L-Arabinose st/n-oxime (SARBOX)243 P21212I Z = 4 D = 1.61 R = 0.04 for 1,387 intensities. The acyclic molecule has the planar, zigzag conformation. The terminal OH and N-OH groups are oriented—syn and ap, respectively. Despite the difference in crystal symmetry, the hydrogen bonding is remarkably similar to that of the anti compound (see preceding abstract), with the same spiral of O-H N bonds. [Pg.336]

The four different periodic tables account for the observed elemental diversity and provide compelling evidence that the properties of atomic matter are intimately related to the local properties of space-time, conditioned by the golden parameter r = l/. The appearance of r in the geometrical description of the very small (atomic nuclei) and the very large (spiral galaxies) emphasizes its universal importance and implies the symmetry relationship of self-similarity between all states of matter. This property is vividly illustrated by the formulation of r as a continued fraction ... [Pg.139]

Until the parallel between number and cosmos is demonstrated to be an illusion we shall use this idea to model the universe. The power of this approach lies therein that all regularities in the physical world can be reduced to the same mathematical rules as the commensurable relationships in the solar system. The same mathematics that optimizes the distribution of matter in spiral galaxies and solar systems, shapes the growth of nautilus shells and sunflower heads. This ubiquitous symmetry, known as self-similarity is... [Pg.306]

In both cases, the loss of mirror symmetry may be caused by a helix either the orientation of the molecular director or the position of the molecules may spiral within the column, or the column lattice is helically distorted. Within the column, mirror symmetry may also be lost by the introduction of tilt and polarization. Similarly to a surface-stabilized (thus nonhelical) smectic C phase of a chiral material, a nonhelical columnar phase of chiral molecules may itself be termed chiral if the optical axis of the molecules is inclined with respect to the column axis the vector of the tilt-induced po-... [Pg.355]

The findings reported here provide new evidence for the unity of micro- and macrophysics and refute the perception of separate quantum and classical domains. The known universe exists as a four-dimensional space-time manifold but is observed in local projection as three-dimensional Euclidean tangent space that evolves in universal time. The observable world, at either micro- or macroscale, can be described in either four-dimensional (nonclassical) or in classical three-dimensional detail. The descriptive model may change, but the reality stays the same. This realization is at the root of self-similarity between large and small. The symmetry operator, which reflects the topology of space-time, is the golden logarithmic spiral. [Pg.111]


See other pages where Spirals, and Similarity Symmetry is mentioned: [Pg.381]    [Pg.381]    [Pg.383]    [Pg.385]    [Pg.387]    [Pg.389]    [Pg.391]    [Pg.393]    [Pg.347]    [Pg.381]    [Pg.381]    [Pg.383]    [Pg.385]    [Pg.387]    [Pg.389]    [Pg.391]    [Pg.393]    [Pg.347]    [Pg.394]    [Pg.157]    [Pg.391]    [Pg.174]    [Pg.189]    [Pg.444]    [Pg.261]    [Pg.82]    [Pg.180]    [Pg.64]    [Pg.236]    [Pg.274]    [Pg.579]    [Pg.87]    [Pg.1359]    [Pg.87]    [Pg.152]    [Pg.378]   


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Spiral symmetry

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Spiraling

Spirality

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