Resumen de Shape is as important as size: roundness and the science of measurement

Christopher J. Sangwin

• Science relies on standards for measurement. This article describes assessment of geometric shape, rather than size. We consider the problem of establishing departure from roundness. In doing this we examine some curious geometric shapes, including non-circular shapes of constant width and shapes that rotate smoothly inside triangles. This has led to the recent reassessment of the standard testing procedures using V-blocks.