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The book's title is similar to a 1995 book title, The Sixth Extinction by Richard Leakey and Roger Lewin. Also included are excerpts from interviews with a forest ecologist , atmospheric scientist Ken Caldeira , wildlife and conservation experts, a modern-day geologist, and fungus researchers in New England and New York State .
In plane geometry, the einstein problem asks about the existence of a single prototile that by itself forms an aperiodic set of prototiles; that is, a shape that can tessellate space but only in a nonperiodic way. Such a shape is called an einstein, a word play on ein Stein, German for "one stone". [2]
The more precise mathematical definition is that there is never translational symmetry in more than n – 1 linearly independent directions, where n is the dimension of the space filled, e.g., the three-dimensional tiling displayed in a quasicrystal may have translational symmetry in two directions.
A tiling that cannot be constructed from a single primitive cell is called nonperiodic. If a given set of tiles allows only nonperiodic tilings, then this set of tiles is called aperiodic . [ 3 ] The tilings obtained from an aperiodic set of tiles are often called aperiodic tilings , though strictly speaking it is the tiles themselves that are ...
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An aperiodic tiling is a non-periodic tiling with the additional property that it does not contain arbitrarily large periodic regions or patches. A set of tile-types (or prototiles) is aperiodic if copies of these tiles can form only non-periodic tilings. The Penrose tilings are a well-known example of aperiodic tilings. [1] [2]
Biotic material, natural material, or natural product, a material produced by a living organism; Biomass, living or dead biological matter, often plants grown as fuel; Biomass (ecology), the total mass of living matter in a given environment, or of a given species; Body fluid, any liquid originating from inside the bodies of living people
A material is a substance or mixture of substances that constitutes an object.Materials can be pure or impure, living or non-living matter. Materials can be classified on the basis of their physical and chemical properties, or on their geological origin or biological function.