By F. Oort

Best geometry and topology books

Algebra and tiling: homomorphisms in the service of geometry

Usually questions about tiling area or a polygon bring about different questions. for example, tiling through cubes increases questions about finite abelian teams. Tiling by way of triangles of equivalent parts quickly contains Sperner's lemma from topology and valuations from algebra. the 1st six chapters of Algebra and Tiling shape a self-contained remedy of those themes, starting with Minkowski's conjecture approximately lattice tiling of Euclidean area by means of unit cubes, and concluding with Laczkowicz's fresh paintings on tiling through comparable triangles.

Algebraic Geometry and Geometric Modeling (Mathematics and Visualization)

This booklet spans the gap among algebraic descriptions of geometric items and the rendering of electronic geometric shapes in keeping with algebraic versions. those contrasting issues of view encourage a radical research of the most important demanding situations and the way they're met. The articles specialise in vital sessions of difficulties: implicitization, class, and intersection.

Additional resources for Algebraic geometry, Oslo 1970; proceedings

Example text

The elimination of the vorticity leads to the pure streamfunction formulation ∂ψ ∂ ∂ψ ∂ ∂ (∆ψ) + (∆ψ) − (∆ψ) = ν∆2 ψ . 24) ∂t ∂y ∂x ∂x ∂y The extension of these approaches to three-dimensional ﬂows requires the introduction of a second streamfunction or the use of a vector potential. The appropriate equations for the former can be found in Murdock (1986) and those for the latter in Brosa and Grossman (2002). 4 Vorticity–Velocity Equations Another approach to eliminating the pressure from the incompressible Navier– Stokes equations is to take the curl of the momentum equation.

A gas is a compressible ﬂuid that not only conforms to the shape of its container but also expands to occupy the full container. Plasma is ionized gas. The various phases of a substance are represented by a phase diagram, which marks the domains in pressure–temperature where each phase exists. 1 illustrates the well-known phase diagram for water. A rigorous mathematical description of the states of matter appears implausible. Goodstein (1975) states: “Precisely what do we mean by the term liquid?

64) as pressure plays a dynamic role rather than a thermodynamic one. 13), and then letting Mref → 0 yields the nondimensional compressible ﬂow equations at zero Mach number: ∂ρ∗ + ∇∗ · (ρ∗ u∗ ) = 0 , ∂t∗ ∂(ρ∗ u∗ ) 1 ∗ ∗ ∇ ·τ , + ∇∗ · (ρ∗ u∗ u∗T ) + ∇∗ p˜ = ∗ ∂t Re ∂(ρ∗ E ∗ ) 1 ∇∗ · (κ∗ ∇∗ T ∗ ) . 4 Incompressible Fluid Dynamics Equations The equations described in the preceding section all have special forms in the incompressible limit. There are several diﬀerent formulations of the incompressible Navier–Stokes equations.