Anisotropiske

Anisotropiske is the adjective used in Norwegian and Danish to describe anisotropic properties—where a material’s or system’s characteristics depend on direction. In science, anisotropy contrasts with isotropy, in which properties are the same in all directions. Anisotropy arises from structural features such as crystal lattices, fiber orientations, or layered compositions, and it can be intrinsic (crystal symmetry) or extrinsic (texturing, fabrication).

Many physical properties are tensorial and direction-dependent. For linear responses, a second-order tensor describes how a field in one direction induces a response in another; diagonalizing the tensor yields principal directions and principal values that quantify the variation. Examples include: optical birefringence where refractive index differs with propagation direction and polarization; electrical and thermal conductivity that vary with direction; and elastic moduli that define stiffness along different axes.

Common examples include: graphite has high in-plane conductivity but low out-of-plane; wood’s strength and stiffness depend on grain direction; composites exhibit anisotropy from fiber layup. In geology, rocks often display anisotropic seismic velocities. In biology, bone and muscle exhibit directional dependence of mechanical properties.

Recognizing anisotropy is essential for modeling and design. Engineers account for it in structures and electronics, scientists use it to tailor optical devices, and material scientists study it to understand fundamental properties.