Two-dimensional effect. The two-dimensional, or planar, Holtzman Effect, which has achieved permanent and deserved notoreity as the common Defensive Shield, is the lowest-order incarnation of die Holtzman Effect to have a physical existence. It consists of the electromagnetic force of atomte bonds, however, these bonding forces have been polarized^ in one direction (the "outside edge" of the effect), the forces have been subverted into acting only on pseudo-atoms of incoherent matter (and can revert With disastrous consequences hi the presence of coherent energy); on the opposite side of the plane, the forces have been shifted so mat they repel normal matter above a certain critical density (ranging from .06 to .35 grams per cubic centimeter). Pseudo-matter, though it does exist, cannot be manifest in real space-time, so the only effects of the Defensive Shield are the effects of the bonding force. The result of the strange half-existence of the planar effect is that normal matter can pass through a planar effect region, but only slowly. In addition, a planar effect is reflective on its outer surface to certain wavelengths of the electromagnetic spectrum, and this reflectivity is determined by the manufacturer of the Shield and cannot be altered once the point-source node for that field has been constructed. In general, the less of the spectrum the field admits, the more unstable it is: nearly aft fields are constructed to admit at least visible light. Fields can be constructed, though, to admit only a single monochrome of the electromagnetic spectrum, or to admit everything but a single monochrome. As matter impinges upon the outside surface of a Holtzman Shield, the electromagnetic bonds in the impinging matter undergo a phenomenon known as "chameleon coating," whereby the matter takes on an outward sheath of pseudo-atoms in a layer a single atom thick, at the intersection lines of the matter and the planar effect. These atoms then sublimate into the planar field as the normal matter passes through the field, and the speed at which this atomic sublimation can proceed determines the velocity, called the "strike speed," at which the normal matter can pass through a planar Holtzman field. This speed varies depending upon the emission spectrum of the planar field, but is never less than 5.81665 cm/s for one-angstrom fields, and increases only to 9.322 cm/s for all-absorptive fields. An object attempting to pass through a planar field at a right-angle vector speed of more than the strike speed is faced with resistance which grows more intense as the fourth power of the velocity. When the speed is sufficiently high, the field becomes essentially solid to the impinging object. Energy "absorbed" by a planar field when it is struck by a fast-moving object is instantaneously re-radiated, in wavelengths throughout the electromagnetic spectrum which complement those which the field admits.