Ductile fracture. The propagation of a ductile crack involves substantial plastic flow and ductile fracture usually gives a characteristic rough fracture surface.Fracture occurs by a process known as microvoid coalescence. First, plastic strain causes small microvoids to form in the material, most often at sites of inclusions.he propagation of a ductile crack involves substantial plastic flow and ductile fracture usually gives a characteristic rough fracture surface.
An illustration of the space-time curvature caused by Earth. Space-time is a mathematical model that joins space and time into a single idea called a continuum. This four-dimensional continuum is known as Minkowski space. Combining these two ideas helped cosmology to understand how the universe works on the big level (e.g. galaxies) and small level (e.g. atoms).
In mathematics, space is an unbounded continuum (unbroken set of points) in which exactly three numerical coordinates are necessary to uniquely define the location of any particular point. It is sometimes called 3-space because it contains three distance dimensions. If a continuum requires fewer or more than three coordinates (dimensions) to uniquely define the location of a point, that continuum is sometimes called n-space or n-dimensional space, where n is the number of dimensions.